AHI estimation system and AHI estimation method
The AHI estimation system uses a ring-shaped wearable device and machine learning to efficiently estimate AHI, addressing the limitations of bulky sensors by reducing power and processing demands while maintaining accuracy.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- SOXAI INC
- Filing Date
- 2024-11-29
- Publication Date
- 2026-06-10
AI Technical Summary
Existing AHI estimation methods require bulky piezoelectric sensors, leading to high power consumption, processing demands, and memory requirements, limiting versatility and ease of use.
An AHI estimation system utilizing a ring-shaped wearable device that acquires pulse wave information to estimate Apnea-Hypopnea Index (AHI) through a machine learning model trained on polysomnography data, incorporating modules for preprocessing, estimation, and post-processing.
Provides a versatile, efficient, and user-friendly method for AHI estimation with reduced power and processing needs, offering accurate health assessments.
Smart Images

Figure 2026094864000001_ABST
Abstract
Description
[Technical Field]
[0001] The present invention relates to an AHI estimation system and an AHI estimation method. [Background technology]
[0002] As background technology for this field, Japanese Patent Publication No. 7158641 (Patent Document 1) can be cited. This publication states that "biometric vibration signals of a subject during sleep are acquired in a non-contact and non-restraining manner, and four parameters are extracted from them: respiratory rate, heart rate, phase coherence calculated from the instantaneous phase difference between the instantaneous phase of fluctuations in heart rate interval and the instantaneous phase of the respiratory pattern, and body movement ratio. Histograms of these parameters are created, feature images are generated from these histograms, and AHI is estimated by inputting these feature images into a pre-trained AHI estimation model" (see abstract). [Prior art documents] [Patent Documents]
[0003] [Patent Document 1] Patent No. 7158641 [Overview of the Initiative] [Problems that the invention aims to solve]
[0004] Patent Document 1 describes a method for estimating AHI (Air-Head Intake) in a non-contact and non-restrained manner by using a sheet-shaped piezoelectric sensor to detect bio-vibration signals based on body movement, heart rate (cardiac pulsation), respiration, and vocalization. However, one aspect of this method is that it requires a bulky sheet-shaped piezoelectric sensor for AHI estimation, which lacks versatility and ease of use. Another aspect is that while the sheet-shaped piezoelectric sensor can detect a relatively large volume of bio-vibration signals, allowing for accurate AHI estimation, it also presents challenges in terms of requiring greater processing power, power consumption, and memory capacity for detecting and transmitting these bio-vibration signals to the AHI estimation device.
[0005] This technology provides a new mechanism for estimating AHI. [Means for solving the problem]
[0006] To solve the above problems, for example, the configuration described in the claims may be adopted. This application includes several means for solving the above-mentioned problems, but one example is: An AH information acquisition unit acquires pulse wave information over time from a living organism and, based on the pulse wave information, acquires AH information indicating the proportion of time during which the living organism experiences apnea (A) and hypopnea (H) during sleep. Based on the aforementioned AH information, an AHI estimation unit estimates the Apnea-Hypopnea Index (AHI), AHI estimation system, It is characterized by providing... [Effects of the Invention]
[0007] According to the present invention, a new mechanism for estimating AHI can be provided. Other issues, configurations, and effects not mentioned above will be clarified by the following description of the embodiments. [Brief explanation of the drawing]
[0008] [Figure 1] Figure 1 shows an example configuration of an AHI estimation system 100 according to one embodiment. [Figure 2] Figure 2 shows an example of the hardware configuration of the wearable device 101. [Figure 3] Figure 3 shows an example of the hardware configuration of user terminal 102. [Figure 4] Figure 4 shows an example of the hardware configuration of the management server 103. [Figure 5] Figure 5 shows an example of health management information according to one embodiment. [Figure 6] Figure 6 shows an example of other health management information according to one embodiment. [Figure 7]FIG. 7 is an overall control flowchart of a sleep health evaluation method according to an embodiment. [Figure 8] FIG. 8 is a sleep-wake evaluation flowchart according to an embodiment. [Figure 9] FIG. 9 is an AH event information acquisition flowchart according to an embodiment. [Figure 10] FIG. 10 is an AH information acquisition flowchart according to an embodiment. [Figure 11] FIG. 11 is a health evaluation flowchart according to an embodiment. [Figure 12] FIG. 12 is a diagram showing a method for acquiring AH event information according to an embodiment. [Figure 13] FIG. 13 is a graph showing the relationship between AH information acquired based on pulse wave information according to an embodiment and manual AHI acquired based on overnight sleep polysomnography information. [Figure 14] FIG. 14 is a graph showing the relationship between estimated AHI according to an embodiment and manual AHI acquired based on overnight sleep polysomnography information. [Figure 15] FIG. 15 is an example of a health management display screen (part) according to an embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0009] Hereinafter, the present technology will be described based on an AHI estimation system and an AHI estimation method according to an embodiment, with appropriate reference to the drawings. In each drawing, for components having the same function, the description may be omitted with reference to the reference numerals.
[0010] [AHI ESTIMATION SYSTEM AND AHI ESTIMATION METHOD] Figure 1 shows an example configuration of an AHI estimation system 100 according to one embodiment. The AHI estimation system 100 and AHI estimation method according to this technology are typically a system and method for monitoring a user's biometric information using a wearable device 101 and estimating AHI. The AHI estimation system 100 comprises one or more wearable devices 101, one or more user terminals 102, and one or more management servers 103. The AHI estimation system 100 may also include one or more chargers 104.
[0011] In one embodiment, the wearable device 101, user terminal 102, management server 103, and charger 104 are configured to send and receive information from each other, for example, via a network. Furthermore, the wearable device 101, user terminal 102, and charger 104 are configured to connect via short-range wireless communication, for example, Bluetooth®. These wearable devices 101, user terminal 102, management server 103, and charger 104 may be configured to send and receive information from each other, for example, via a network, but only among themselves. Also, any two or more of the functional elements of the wearable device 101, user terminal 102, management server 103, and charger 104 may be configured as a single unit, or any of them may be separated into two or more units and configured independently.
[0012] The wearable device 101 is a terminal that a user (an example of a living organism) wears on their own body. User terminal 102 is a terminal used by a user of the wearable device 101 or the AHI estimation system 100. The management server 103 is a terminal used by the administrator who manages this AHI estimation system 100.
[0013] Each terminal and management server 103 in the AHI estimation system 100 may be a mobile device such as a smartphone, tablet, mobile phone, or personal digital assistant (PDA), or it may be a wearable device such as glasses (including goggles), a wristwatch, or clothing. The management server and terminals may also be a stationary or portable computer, or a server located in the cloud or on a network. From a functional standpoint, they may also be VR (Virtual Reality), AR (Augmented Reality), or MR (Mixed Reality) terminals. Alternatively, the management server and terminals may be a combination of multiple such terminals. For example, a combination of one smartphone and one wearable device can logically function as a single terminal. Each terminal may also be an information processing terminal other than those mentioned above.
[0014] Each terminal and management server 103 of the AHI estimation system 100 may optionally be equipped with a processor that runs an operating system, applications, and programs; main memory such as RAM (Random Access Memory); auxiliary storage such as an IC card, hard disk drive, SSD (Solid State Drive), and flash memory; a communication control unit such as a network card, wireless communication module, or mobile communication module; an input device such as a touch panel, keyboard, mouse, voice input device, motion controller, or motion detection device using image capture from a camera; an output device such as a monitor, display, printer, audio output device, or oscillator; and a timing device. The input device may also be equipped with sensors such as GPS, gyro sensors, and acceleration sensors. The output device may be a device or terminal that transmits information for output to an external monitor, display, printer, or other device.
[0015] The main memory stores various programs and applications (software modules), and the processor executes these programs and applications to realize each functional element of the overall system. These modules may be implemented by one or more programs or applications. Furthermore, each module may be implemented by an independent program or application, or it may be implemented as a subprogram or function within a single integrated program or application. These modules may also be implemented in hardware by integrating circuits or employing a microcomputer (hardware modules).
[0016] Furthermore, each module may be implemented by a single processor or by multiple processors. Also, each module may be installed in a single terminal (including a management server) or divided among two or more terminals (including management servers) interconnected via a network. Furthermore, each module may be installed in each, or one or more, of the two or more terminals (including management servers) interconnected via a network. Consideration is also given to cases where some modules are implemented in different countries from others.
[0017] In this specification, each module is described as the entity (subject) that performs the processing; however, in reality, processing is carried out by the processor executing various programs and applications.
[0018] Auxiliary storage devices store various databases (DBs). A "database" is a collection of data organized and collected to accommodate arbitrary data operations (e.g., extraction, addition, deletion, overwriting, etc.) from a processor or external computer. An auxiliary storage device is a functional element (storage unit) that stores one or more data collections. The implementation method of a database is not limited; for example, it may be a database management system, spreadsheet software, or text files such as XML or JSON. A database may be independently provided and connectable to a processor, etc. A database is assumed to store some or all of the information constituting the data collection in a JSON format file, but is not limited to this. A database may be configured to store various types of information as a relational database or a non-relational database.
[0019] [Management Server] Figure 4 shows an example of the hardware configuration of the management server 103. The management server 103 is composed of a computer server located, for example, on the cloud. The management server 103 includes a main memory 401 and an auxiliary memory 402. The management server 103 also includes the processor 403 as described above, an input device 404, an output device 405, and a communication control unit 406.
[0020] The main memory 401 stores programs and applications such as the execution module 411, health management module 412, health information evaluation module 413, pre-processing module 414, post-processing module 415, and model adjustment module 416. The processor 403 executes these programs and applications to realize each functional element of the management server 103.
[0021] The execution module 411 controls the basic operation of the management server 103 for providing services by the AHI estimation system 100. For example, the execution module 411 works in conjunction with the execution module 311 of the user terminal 102 to control the basic operation for causing the user terminal 102 to execute the AHI estimation service. The execution module 411 can also support the operation of each module, as described later, and the coordination between each module. The execution module 411 may also be configured to work in conjunction with the execution module 211 of the wearable device 101, for example.
[0022] The health management module 412 acquires the user's biometric information. The health management module 412 also provides health management information to the user terminal 102. For example, the health management module 412 acquires the user's biometric information using a wearable device 101, and outputs the results of the user's health evaluation, which is evaluated by the health information evaluation module 413 based on the acquired biometric detection information of the user, to the user terminal 102. The health management module 412 is an example of an acquisition unit in this technology.
[0023] The health information evaluation module 413 evaluates the user's health status. For example, the health information evaluation module 413 estimates and evaluates the user's health status based on various biometric detection information of the user acquired by the wearable device 101. In this embodiment, the health information evaluation module 413 estimates the user's AHI using, for example, an AHI estimation model. The health information evaluation module 413 is an example of the AHI estimation unit in this technology. Hereinafter, the AHI estimated by the health information evaluation module 413 may simply be referred to as "estimated AHI".
[0024] The AHI estimation model M is a machine learning model trained to take features related to apnea and hypopnea (excluding AHI) obtained from the organism's overnight polysomnography (PSG) data as input, and to output the AHI obtained from the same overnight polysomnography data (hereinafter referred to as "manual AHI"). In this technology, a polynomial regression model is used as the machine learning model. Furthermore, as features related to apnea and hypopnea, AH information, which indicates the proportion of time during sleep in the organism that is apnea (A) and hypopnea (H), obtained from the organism's overnight polysomnography data, is adopted. AH information will be described later.
[0025] The preprocessing module 414 is an element that processes (preprocesses) various biometric detection information of the user prior to inputting it to the health information evaluation module 413. For example, the preprocessing module 414 preprocesses various biometric detection information of the user, which is the input, so that the health information evaluation module 413 can perform a more appropriate evaluation (including estimation). For example, the preprocessing module 414 acquires AH information, which indicates the percentage of time the user experiences apnea (A) and hypopnea (H) during sleep, based on the user's pulse wave information, as input information for the health information evaluation module 413. The preprocessing module 414 is an example of an AH information acquisition unit in this technology.
[0026] The post-processing module 415 is an element that performs additional processing (post-processing) on the output of the health information evaluation module 413. For example, the post-processing module 415 performs post-processing on the estimated AHI, which is the output of the health information evaluation module 413, so that the user can better understand it. For example, the post-processing module 415 obtains the severity of sleep apnea syndrome based on the estimated AHI. The post-processing module 415 is an example of a symptom evaluation unit in this technology.
[0027] The model adjustment module 416 is an element that trains and further trains the AHI estimation model M. The model adjustment module 416 acquires overnight polysomnography information and manual AHI based on this overnight polysomnography information, acquires AH information based on the overnight polysomnography information, and trains the machine learning model to take the acquired polysomnography-derived AH information as input and output manual AHI. In addition, the model adjustment module 416 acquires new overnight polysomnography information at predetermined timings, for example, and further trains the AHI estimation model M based on the acquired overnight polysomnography information. The model adjustment module 416 is an example of a model adjustment unit in this technology.
[0028] The auxiliary storage device 402 stores various types of information necessary for realizing the above-mentioned functions of the management server 103. For example, the auxiliary storage device 402 stores user information 410, health management information 420, AHI estimation model information 430, etc. The implementation method of each type of information stored in the auxiliary storage device 402 is not limited to this embodiment, and each type of information may be implemented in a distributed manner across multiple database servers or cloud applications.
[0029] User information 410 is, for example, information about a user who uses the AHI estimation system 100. Typically, user information 410 is a user of the wearable device 101. User information 410 is not limited to, but may include, for example, user identification information, information about the user's attributes such as gender and age, and information from a health questionnaire about the user. Each piece of information is stored, for example, linked to user identification information.
[0030] Figures 5 and 6 show an example of health management information 420 according to one embodiment. Health management information 420 is information acquired, calculated, or estimated by the AHI estimation system 100. The figure illustrates, for example, the information stored in the auxiliary memory device from the health management information 420. Health management information 420 may include, for example, sleep / wake flag information (sleep / wake information) shown in (A), PPG sensor information and SpO2 information shown in (B), threshold (Th) information and event count information (AH event information) shown in (C), AH information (TRah) shown in (D), and estimated AHI information. Each of these pieces of information is associated with time (time) information. The content of each piece of information will be described later. The auxiliary memory device can store information other than the information shown in the figure.
[0031] The AHI estimation model information 430 is information necessary for using the AHI estimation model M in the AHI estimation system 100. The AHI estimation model information 430 may include, for example, the entire AHI estimation model M, i.e., the model function and parameters and the program for operating it, or it may include parameters for operating a machine learning model stored on an external server, etc.
[0032] [User terminal] Figure 3 shows an example of the hardware configuration of user terminal 102. The user terminal 102 is composed of a device such as a smartphone, tablet, notebook PC, or desktop PC. The user terminal 102 includes a main memory 301 and an auxiliary memory 302. The user terminal 102 also includes the processor 303 as described above, an input device 304, an output device 305, a camera 306, and a communication control unit 307.
[0033] The main memory 301 of the user terminal 102 stores programs and applications such as the execution module 311, health management module 312, health information evaluation module 313, pre-processing module 314, post-processing module 315, and model adjustment module 316. The processor 303 executes these programs and applications to realize each functional element of the user terminal 102. In other words, the main memory 301 of the user terminal 102 stores the same functional modules as the main memory 401 of the management server 103, and the user terminal 102 can perform the same processing as the management server 103.
[0034] As will be described later, the main memory 301 of the user terminal 102 stores a health management application program that manages the user's health based on sensor data acquired from the ring-shaped wearable device 101. This health management application program includes, for example, a sleep detection program that detects the sleep state and an application program for performing sleep analysis.
[0035] The functions of each of these modules are the same as those described above, so their explanation will be omitted. Note that the main memory 301 does not necessarily have to store all of the same functional modules as the management server 103; it may store only some of the functional modules (for example, the execution module 311 and the health management module 312).
[0036] The auxiliary storage device 302 stores various types of information necessary for realizing the above-mentioned functions of the user terminal 102. The auxiliary storage device 302 can store, for example, user information 310, health management information 320, AHI estimation model information 330, etc. Each of these pieces of information may be, for example, a part of the information stored in the management server 103 (for example, AH event information, health management information including AHI severity information, etc.).
[0037] [Wearable devices] The wearable device 101 is a device that can be attached to a living body such as a human being, thereby non-invasively acquiring the biological information of that living body as digital information. The wearable device 101 according to this embodiment is a ring-shaped device that is attached to a human finger, for example, as shown in Figure 1. Figure 2 shows an example of the hardware configuration of the wearable device 101 according to one embodiment.
[0038] The wearable device 101 includes a main memory 201 and an auxiliary memory 202. The management server 103 also includes the processor 203 as described above, a sensor module 204, a gyro sensor / accelerometer module 205, a charge management module 206, and a communication control unit 207. The sensor module 204 and the gyro sensor / accelerometer module 205 are examples of input devices.
[0039] The processor 203 is a digital signal processing device that controls the operation of, for example, the sensor module 204, the gyro sensor / accelerometer module 205, the charge management module 206, and the communication control unit 207. The processor 203 can be, for example, an MCU (Micro Controller Unit) or an MPU (Micro Processor Unit). The storage device can be, for example, flash memory or EEP-ROM (Electrically Erasable Programmable Read-Only Memory). The wearable device 101 may also include an output device (not shown).
[0040] The sensor module 204 controls, for example, the operation of various sensors provided in the wearable device 101 and the sensor signals. The sensor module 204 also controls, for example, the operating conditions of the sensors. The sensor module 204 may include, for example, a digital processing function such as a Digital Signal Controller (DSC), Digital Signal Processor (DSP), or FPGA (Field Programmable Gate Array) that processes sensor data acquired by the sensors in real time. The sensor module 204 includes, for example, any combination of resistors, capacitors, coils, diodes, transistors, etc., and can optionally include circuits such as amplifiers, clocks, bandgap references, digital isolators, RC filters (e.g., low-pass filters, high-pass filters), band-pass filters, band-elimination filters, and analog-to-digital converters. Furthermore, the sensor module 204 may include, for example, analog circuit blocks that process signals acquired via the sensors, such as an RMS-DC converter circuit, an average value detection circuit, an RMS detection circuit, a signal monitoring circuit, and an adaptive threshold setting circuit. Furthermore, the sensor module 204 can be configured to perform various signal processing tasks using any combination of analog circuits and / or digital processing functions.
[0041] The wearable device 101 includes, for example, a pulse wave sensor S1, a temperature sensor S2, a microwave sensor S3, an electrocardiogram sensor S4, etc., and the sensor module 204 is connected to these sensors S1 to S4. These sensors S1 to S4 are examples of signal detection devices (sensors) for detecting various types of biological information, and are examples of input devices for the wearable device 101. Each sensor S1 to S4 may also be equipped with a digital signal controller (DSC) that processes sensor data in real time.
[0042] The pulse wave sensor S1 is a photoplethysmogram (PPG) sensor that detects changes in the volume of blood vessels (e.g., arteries) in a living organism. In a ring-shaped wearable device 101, the pulse wave sensor S1 can typically be a reflective pulse wave sensor comprising a light-emitting element that emits light of a predetermined wavelength toward the living organism and a light-receiving element that detects the light reflected within the living organism. The light-emitting element can be made up of, for example, various types of light-emitting diodes (LEDs), and the light-receiving element can be made up of, for example, various types of photodiodes (PDs).
[0043] By analyzing the PPG signal acquired by the PPG sensor, various biological information can be obtained. Specifically, for example, the light-emitting element can be equipped with a green LED that generates light with a central wavelength of 500 nm to 600 nm. Green light has a high absorption rate by hemoglobin in the blood and is less affected by ambient light such as sunlight, so a relatively stable volume pulse wave can be measured. Based on the pulsation of this volume pulse wave obtained with green light, for example, reliable heart rate and heart rate variability information can be obtained.
[0044] Furthermore, oxyhemoglobin, deoxyhemoglobin (also called reduced hemoglobin), and glycated hemoglobin may each have different absorption coefficients (typically, absorption spectra) for red light or near-infrared light wavelengths. Therefore, as a suitable example, a light-emitting element may include a combination of a red LED with a central wavelength of 630 nm to 690 nm and an infrared LED with a central wavelength of 810 nm to 990 nm. Based on the difference in the absorption coefficients of these two types of light for oxyhemoglobin and deoxyhemoglobin, SpO2 (Peripheral Blood Oxygen Saturation), blood oxygen concentration, and heart rate can be obtained.
[0045] As another suitable example, the light-emitting element may include a combination of three or more (e.g., three or four) different LEDs that generate light with central wavelengths between 600 nm and 990 nm. Based on the difference in the extinction coefficients of oxyhemoglobin, deoxyhemoglobin, and glycated hemoglobin, blood hemoglobin concentration, blood glycated hemoglobin concentration, etc., can be calculated.
[0046] Furthermore, the light-emitting element may include LEDs that generate light of different wavelengths than those mentioned above. Since hemodynamic information is convolved into the shape of the pulse wave, blood pressure can be estimated by analyzing the shape of the volume pulse wave. Also, by analyzing the shape of the volume pulse wave, blood viscosity can be estimated, and blood glucose levels can be detected from the blood viscosity. For blood glucose measurement, spectroscopic methods (e.g., near-infrared spectroscopy, Raman spectroscopy, infrared spectroscopy, etc.) may be used. For example, the light-emitting element may include a combination of two or more (e.g., two or three) LEDs that generate near-infrared light with a central wavelength of approximately 1200 nm to 1600 nm. This allows blood glucose levels to be calculated based on the light absorption spectrum derived from glucose.
[0047] The pulse wave sensor S1 of this embodiment is, for example, a multi-wavelength PPG sensor capable of emitting and receiving (detecting) at least infrared and red light, and capable of calculating SpO2.
[0048] The temperature sensor S2 is an optional sensor capable of detecting the temperature (body temperature) of a living organism. Typically, the temperature sensor S2 can detect information regarding the skin temperature or core body temperature of a living organism. The temperature sensor S2 is not limited to this, but for example, a thermopile-type infrared sensor can be used.
[0049] The microwave sensor S3 is an optional sensor that can be installed and, for example, detect the frequency characteristics around the resonant frequency by radiating microwaves onto a living organism. By analyzing these frequency characteristics, information such as skin moisture content, sweat volume, and blood glucose levels can be obtained.
[0050] The electrocardiogram sensor S4 is an optional sensor capable of detecting electrical activity associated with the movement of the heart. The electrocardiogram sensor S4 can be used as one measuring electrode in various lead methods. Therefore, for example, the electrocardiogram sensor S4 may be configured to obtain electrocardiogram information in cooperation with other electrocardiogram sensors S4 provided on other wearable devices 101. As an example, electrocardiogram information can be obtained using the bipolar lead method with two ring-shaped wearable devices 101 worn on the fingers of both the left and right hands. Alternatively, electrocardiogram information may be obtained using a combination of a ring-shaped wearable device 101 worn on the finger of one hand, a wristwatch-shaped wearable device 101 worn on the wrist of the other hand, a user terminal 102 (smartphone, etc.), or a medical device, etc.
[0051] The gyro sensor / accelerometer module 205 is equipped with a gyro sensor and an accelerometer. The gyro sensor / accelerometer module 205 can detect the angular velocity and acceleration of the wearable device 101 and can detect changes in the position of the wearable device 101 (displacement, tilt, movement, etc.). In addition, the gyro sensor / accelerometer module 205 can acquire information regarding the posture, activity level, activity level, calories burned, steps taken, and behavioral discrimination of the person wearing the wearable device 101.
[0052] Furthermore, the gyro sensor / accelerometer module 205, like the sensor module 204 described above, can optionally be equipped with digital processing functions such as a DSC, DSP, or FPGA for processing sensor data acquired by the sensor in real time, as well as various analog circuits.
[0053] The charge management module 206 is an element that manages charging in the charging system provided in the wearable device 101. Figure 2 shows an example of a wireless charging system that charges the secondary battery 208 from the charger 104 without physical contact via a wireless charging receiver 209. However, the wearable device 101 may be configured to charge via contact with the charger 104 by providing contact electrodes (not shown) instead of, and / or in addition to, the wireless charging receiver 209.
[0054] The wireless charging system includes, for example, a charge management module 206, a secondary battery 208, and a wireless charging receiver 209, all of which are provided in a wearable device 101, and an external charger 104. The charge management module 206 manages the charging process to prevent overcurrent, overvoltage, overheating, etc., of the secondary battery 208. The secondary battery 208 is not particularly limited, but examples include lithium-ion batteries, lithium polymer batteries, and all-solid-state lithium-ion batteries.
[0055] Furthermore, various charging systems can be employed as wireless charging systems, such as electromagnetic induction, magnetic field resonance, electric field coupling, and radio wave reception. For example, a wireless charging system compatible with Near Field Communication (NFC) or Qi standards can be preferably adopted in this embodiment. Among these, a system compatible with the NFC standard is preferable because it allows for miniaturization and cost reduction.
[0056] The communication control unit 207 is configured to connect to other terminals (e.g., user terminal 102) via a network. The network can be wired or wireless, and each terminal can send and receive information from each other via the network. In the case of wireless communication, communication devices conforming to standards such as Bluetooth®, WiFi®, or LTE® can be used. In this embodiment, the communication control unit 207 connects to the user terminal 102 via BLE (Bluetooth Low Energy) communication.
[0057] The wearable device 101 stores programs and applications such as an execution module 211, a health management module 212, a health information evaluation module 213, a pre-processing module 214, a post-processing module 215, and a model adjustment module 216 in its main memory 201. The processor 203 then executes these programs and applications to realize each functional element of the wearable device 101. In other words, by storing the same functional modules in the main memory 201 of the wearable device 101 as in the main memory 401 of the management server 103, the wearable device 101 can perform the same processing as the management server 103.
[0058] The functions of each of these modules are the same as described above, and their explanation will be omitted. Note that the main memory 201 does not necessarily have to contain all of the same functional modules as the management server 103. Alternatively, it may contain only some of the same functional modules as the management server 103 (for example, the pre-processing module 214). Furthermore, each functional module may be composed of some or all analog circuits. As will be described later, as an example, the main memory 201 contains the pre-processing module 214.
[0059] The auxiliary storage device 202 stores various types of information necessary for realizing the above-mentioned functions of the wearable device 101. The auxiliary storage device 202 can store, for example, user information, health management information, AHI estimation model information, etc. In this embodiment, the auxiliary storage device 202 stores, for example, some of the information stored in the management server 103 (for example, health management information including AH event information and sleep-wake information).
[0060] [Methods for assessing sleep health] Next, a sleep health assessment method according to one embodiment will be described. The AHI estimation system 100 allows for the evaluation of the user's sleep health status by operating the wearable device 101 in "sleep health assessment mode".
[0061] In the sleep health assessment mode, for example, the following items related to "breathing status during sleep" are evaluated: Estimated AHI • Assessment of the severity of sleep apnea syndrome • Time data of sleep apnea-hypopnea events
[0062] Figure 7 is an overall control flow diagram of a sleep health assessment method according to one embodiment. In the user terminal 102, for example, when the user selects to turn "Sleep Health Assessment Mode" to "ON" (i.e., gives an action command), the execution module 311 of the user terminal 102 sends an instruction to the wearable device 101 to operate in Sleep Health Assessment Mode. The execution module 311 of the user terminal 102 may also send information to the management server 103 indicating that it has received an instruction from the user to turn on Sleep Health Assessment Mode.
[0063] Furthermore, the execution module 311 may, when the "sleep health evaluation mode" is ON, send an instruction to the wearable device 101 to operate in sleep health evaluation mode at a predetermined time (for example, the scheduled bedtime of 9 PM) or during a predetermined time period (for example, from the scheduled bedtime of 9 PM to 6 AM the next day). Alternatively, the execution module 311 may send an instruction to the wearable device 101 to operate in sleep health evaluation mode at a predetermined time (for example, the scheduled bedtime of 9 PM) or during a predetermined time period (for example, from the scheduled bedtime of 9 PM to 6 AM the next day).
[0064] In sleep health assessment mode, the wearable device 101 (ring) generally performs (1) sleep / wake assessment and (2) acquires AH event information. Then, for example, when the user wakes up, it transmits the acquired information to the management server 103 via the user terminal 102. Based on this information, the management server 103, for example, (3) acquires AH information and (4) estimates AHI based on the acquired AH information. The management server 103 also performs (5) a health assessment related to sleep. The management server 103 adjusts the (6) AHI estimation model. The management server 103 then transmits the health assessment related to sleep to the user terminal 102, and the user terminal 102 provides the health assessment results to the user. The following describes each process. However, this technology does not require all of the above processes (1) to (6) to be performed.
[0065] (1) Sleep-wake assessment Figure 8 is a sleep-wake evaluation flowchart according to one embodiment. The execution module 211 of the wearable device 101 operates each module in sleep health evaluation mode based on instructions from, for example, the user terminal 102. In sleep health evaluation mode, the health management module 212 and the pre-processing module 214 of the wearable device 101 execute the sleep-wake evaluation flow 800.
[0066] The sleep-wake evaluation flow 800 includes, for example, the following steps: acquiring acceleration sensor information (S810), evaluating sleep or wakefulness per unit time (S820), and assigning sleep or wakefulness flags (S830, 840, 850).
[0067] The health management module 212 first acquires acceleration information from the gyro sensor / accelerometer module 205 (step S810). Here, acceleration information is an example of user activity level information. The health management module 212, for example, sends an instruction to the gyro sensor / accelerometer module 205 to operate the acceleration sensor and acquire acceleration information over time at a predetermined sampling rate. Although the conditions for acquiring acceleration information are not strictly limited, for example, the sampling rate can be approximately 10 to 30 Hz (for example, approximately 12.5 Hz). Also, the acceleration information can be, for example, 3-axis acceleration information in the x, y, and z axes.
[0068] The preprocessing module 214 evaluates whether the user wearing the wearable device 101 is in a sleep or wakeful state based on the acquired acceleration information (step S820). For sleep / wake determination based on acceleration information (an example of activity level information), a sleep determination algorithm can be used, for example. Examples of sleep determination algorithms include the Cole-Kripke algorithm and the Sadeh algorithm.
[0069] In this embodiment, the Cole-Kripke algorithm is employed. The preprocessing module 214 obtains, for example, representative values of activity intensity data within a predetermined time interval (window) from the acquired acceleration information. Examples of representative values of activity intensity data for a predetermined time include the mean, median, and peak values of the vector norm (which may be a simplified norm with the square root omitted) for a period of 0.5 to 5 minutes (for example, 1 minute). The preprocessing module 214 may, as an optional step, take a moving average of the representative values of activity intensity data within a 1-minute window and average them. Next, the preprocessing module 214 calculates a weighted score for the representative values of activity intensity data according to the Cole-Kripke algorithm. The weighted score can be calculated, for example, by applying the weights of the Cole-Kripke algorithm to the data in the preceding and succeeding windows (for example, 3 minutes before and after) and summing them with the data in the window of the time to be evaluated. The weights are not limited to these examples, but one example is to assign a weight of "1" to the time being evaluated, a weight of "0.20" to times within ±1 minute, and a weight of "0.04" to times within ±2 minutes.
[0070] The preprocessing module 214 then determines, for example, that the user is "sleeping" if the weighted score for the time period being evaluated is less than a predetermined threshold, and that the user is "awake" if the weighted score is greater than the predetermined threshold. The threshold for the weighted score cannot be generalized as it depends on the configuration of the accelerometer and how the weights are assigned, but it can be set based on pre-acquired weighted scores and the user's actual activity status. Furthermore, the threshold for the weighted score can be empirically set and updated, for example, according to the characteristics of the user's activity intensity.
[0071] Then, if the preprocessing module 214 evaluates the time as "sleep" (Y in S830), it associates a "sleep flag" indicating sleep with the evaluation time (S840). Furthermore, if the preprocessing module 214 evaluates the system as "awakened" (N in S830), it associates an "awakening flag" indicating awakening with the evaluation time (S850). The preprocessing module 214 stores (outputs) sleep-wake information, which associates the evaluation target time with a sleep or wake flag (sleep / wake flag information), in the auxiliary storage device 202.
[0072] The processing steps S810-850 described above may be performed by the gyro sensor / accelerometer module 205, and the preprocessing module 214 may acquire the processing results (e.g., sleep-wake information).
[0073] (2) Acquisition of AH event information If the sleep-wake evaluation flow 800 described above is evaluated as "sleep," the health management module 212 executes the AH event information acquisition flow 900 in parallel with the sleep-wake evaluation flow 800. Figure 9 is a flowchart illustrating the acquisition of AH event information according to one embodiment.
[0074] The AH event information acquisition flow 900 includes, for example, the following steps: pulse wave sensor information acquisition step (S910), SpO2 information acquisition step (S920), threshold setting step (S930), second average SpO2 value calculation step (S940), average SpO2 value evaluation step (S950), AH event addition step (S960), confirmation step (S970), confirmation step (S980), and AH event information output step (S990).
[0075] The health management module 212 first acquires pulse wave sensor information from the sensor module 204 (step S910). The health management module 212, for example, sends an instruction to the sensor module 204 to operate the pulse wave sensor S1 and acquire a photoelectric volume pulse wave (PPG) signal over time at a predetermined sampling rate. Here, as described above, the pulse wave sensor S1 is equipped with a red LED and an infrared (IR) LED, and is capable of detecting reflected red and infrared light from the living body. The PPG signal includes the intensity signal of the reflected red light from the living body and the intensity signal of the reflected infrared light from the living body. Although the conditions for acquiring the PPG signal are not strictly limited, for example, the sampling rate can be approximately 10 to 50 Hz (for example, approximately 25 Hz).
[0076] The preprocessing module 214 then acquires SpO2 information based on the acquired PPG signal (S920). The preprocessing module 214 may, for example, cause the DSC of the sensor module 204 or pulse wave sensor S1 to perform part or all of the process of calculating SpO2 from the acquired PPG signal. In this embodiment, the preprocessing module 214 causes the DSC to perform the following process and acquires the calculated SpO2.
[0077] Of the PPG signal, the direct current (DC) component originates from the absorption of light by venous blood and tissues and hardly changes with the heartbeat (pulsation). On the other hand, the alternating current (AC) component fluctuates in accordance with the periodic increase and decrease in blood (arterial blood) volume due to the heartbeat. From this, the oxygenation state of arterial blood can be calculated through the ratio of the AC and DC components of red light and infrared light. Therefore, DSC, for example, converts the PPG signals from red LEDs and infrared LEDs into ADC signals through a ΔΣ A / D converter, divides these ADC signals into pulses corresponding to the heartbeat, and calculates SpO2 for each pulse. SpO2 can be calculated, for example, by the following formula.
[0078]
number
[0079] Here, in the formula, AC_ir: Maximum value of infrared LED - Minimum value of infrared LED AC_red: Maximum value of red LED after HPF - Minimum value of red LED DC_ir: Peak value of infrared LED DC_red: Peak value of red LED Furthermore, A, B, and C are calibration coefficients that vary depending on the sensor and installation conditions, etc., and can be set based on an empirical calibration formula by conducting tests in advance, for example. Note that the values after passing through a high-pass filter or moving average filter may be used as AC_ir, AC_red, DC_ir, and DC_red.
[0080] In the following steps S930-S970, AH event information is acquired based on the sequentially acquired SpO2. Figure 12 is a diagram showing a method for acquiring AH event information according to one embodiment. In the following description, Figure 12 will be referred to as appropriate. In the graph of Figure 12, the solid line shows the SpO2 measurement results.
[0081] Here, AH event information refers to information indicating the number of times an apnea-hypopnea event (AH event), in which the organism is in an apnea (A) state and a hypopnea (H) state, occurs per unit time. For example, it can be defined by the number of times SpO2 falls below a predetermined threshold per unit time. In this embodiment, the number of AH events is counted for each first time window. Whether or not an AH event has occurred is evaluated for each second time window, by further dividing the first time window into a plurality of second time windows.
[0082] Although the processing in steps S930 to S970 is described as being performed by the pre-processing module 214, it is also possible that some or all of the processing is performed by the sensor module 204 (or sensor S1), and the pre-processing module 214 acquires the processing results (for example, AH event information).
[0083] First, the preprocessing module 214 sets a threshold for acquiring AH event information (S930). As a predetermined threshold, SpO2 can be used to distinguish between normal breathing during sleep, apnea (A), and hypopnea (H). In a healthy body, the resting SpO2 is 100% throughout sleep and wakefulness. For example, if the SpO2 is in the range of approximately 95% to 100%, it can be determined that it is a normal breathing state without apnea or hypopnea. Also, for example, if the SpO2 is in the range of approximately 85% to 90%, it can be determined that it is a hypopnea state, and if the SpO2 is approximately 70% or less, it can be determined that it is an apnea state.
[0084] Therefore, the pre-treatment module 214 can adopt an index that can distinguish between a normal respiratory state and an AH state as a predetermined threshold. In this embodiment, for example, the pre-treatment module 214 sets the threshold to a value 3% lower than the average value of SpO2 at the first time (i.e., 97% of the average value). In Figure 12, the dotted line labeled BL represents the average SpO2 value (first average value) for the first time period (in this case, 5 minutes), and the dotted line labeled Th represents the threshold value for that first time period.
[0085] The unit of time (first time) used as the basis for counting the number of AH events can be set within a range that balances data reliability and load, for example, 1 to 10 minutes (for example, 5 minutes) can be used as a guideline. The first average value and threshold are calculated for each of the first time windows.
[0086] Next, the preprocessing module 214 calculates a second average SpO2 value in the first time period, which is the average of the SpO2 values over a second time period that is shorter than the first time period (S940). The second time period can be approximately 1 / 10 to 1 / 100 of the first time period. Figure 12 shows the case where the second time window is 10 seconds. Within the first time period of 5 minutes, 30 second windows of 10 seconds each are formed.
[0087] The preprocessing module 214 then evaluates whether the second mean SpO2 value falls below the predetermined threshold (second mean SpO2 < threshold?) (S950). In other words, it evaluates whether an apnea-hypopnea event (AH event) has occurred in the second time window. If the second mean SpO2 value is less than the predetermined threshold (Y in S950), the preprocessing module 214 assumes that an AH event has occurred and increments the AH event count by 1 (+1) (S960). The preprocessing module 214 stores the AH event count in the auxiliary storage device 202 each time, for example, linked to time information (for example, the start time of the first time window). If the second mean SpO2 value is greater than or equal to the predetermined threshold (N in S950), the preprocessing module 214 assumes that no AH event has occurred and proceeds to the next step without incrementing the AH event count.
[0088] The preprocessing module 214 checks, for example, whether it has evaluated whether an AH event occurred for all second time windows within the first time window (S940-S960) (S970). If it has evaluated whether an AH event occurred for all second time windows (30 second windows in Figure 12) (Y in S970), the preprocessing module 214 moves on to the next step S980. If it has not evaluated whether an AH event occurred for all second time windows (N in S970), the preprocessing module 214 returns to step S940 and evaluates whether an AH event occurred for the remaining second time windows.
[0089] The preprocessing module 214 checks whether the user is evaluated as "awake" in the sleep-wake evaluation flow 800 (S980). If the user is evaluated as "awake" (Y in S980), the preprocessing module 214 proceeds to the next step S990. If the user is not evaluated as "awake" (N in S980), the preprocessing module 214 returns to step S930 and obtains the number of AH events for the next first time window. In other words, the preprocessing module 214 repeatedly executes steps S910 to S980 in the sleep-wake evaluation flow 800 from the time the user is evaluated as "sleeping" until the time they are evaluated as "awake".
[0090] When the user is evaluated as "awake," the preprocessing module 214 stores (outputs) the number of AH events acquired for each first time window, for example, as shown in Figure 5(C), in the auxiliary storage device 202 as AH event information (S990). This information is associated with the information about the first time window (e.g., the start time).
[0091] In the sleep-wake evaluation flow 800, if the user is evaluated as "sleeping," the pre-processing module 214, in cooperation with the pre-processing module 314 of the user terminal 102, transmits the AH event information and sleep-wake information stored in the auxiliary storage device 202 to the user terminal 102. The pre-processing module 314 of the user terminal 102, in cooperation with the pre-processing module 414 of the management server 103, transmits the AH event information and sleep-wake information acquired from the wearable device 101 to the management server 103. The pre-processing module 414 of the management server 103 stores the acquired AH event information and sleep-wake information in the auxiliary storage device 402. Here, the information transmitted and received between the wearable device 101, the user terminal 102, and the management server 103 is flag information (sleep-wake information) associated with time information related to a predetermined time window, and event count information (AH event information) associated with time information related to a first time window, and the amount of information is reduced compared to raw data (or simply digitized data).
[0092] (3) Acquisition of AH information Next, in the management server 103, the preprocessing module 414 acquires AH information for estimating AHI. Here, AH information refers to information that indicates the proportion of time during sleep when the body experiences apnea (A) and hypopnea (H).
[0093] Figure 10 is a flowchart illustrating the acquisition of event information according to one embodiment. The event information acquisition flow 1000 includes, for example, the following steps: acquisition of AH event information (S1010), acquisition of total AH event duration (S1020), acquisition of sleep-wake information (S1030), total sleep duration (S1040), acquisition of AH information (S1050), and output of AH information (S1060). Here, steps S1010-S1020 and steps S1030-S1040 are not in any particular order.
[0094] The preprocessing module 414, for example, obtains AH event information from the auxiliary storage device 402 (S1010) and obtains the total duration of AH events during the evaluation time (S1020). Total duration of AH events T AH For example, it can be calculated from the following formula. T AH =Σ(Number of AH events in each first time period) × (Second time period) If the second time is the same for all first time periods, the preprocessing module 414 multiplies the total number of AH events for all first time periods by the second time period to obtain the total duration T of the AH events. AH It is possible to calculate this.
[0095] Furthermore, the preprocessing module 414 acquires sleep-wake information from the auxiliary storage device 402 (S1030), for example, and obtains the total sleep time during the evaluation period (S1040). Total sleep time T SL For example, it can be calculated from the following formula. T SL = (Total number of sleep flags) × (Determined time in the sleep-wake evaluation flow 800) Depending on how the flag is recorded, the total sleep time T SL can be calculated by subtracting the end time of sleep (start time of awakening) from the start time of sleep.
[0096] Then, the preprocessing module 414 obtains the AH information from the obtained total time T of the AH event AH and the total sleep time T SL (S1050). The AH information TRah can be calculated from, for example, the following formula. TRah = T AH / T SL The preprocessing module 414 records (outputs) the obtained AH information in the auxiliary storage device 402 (S1060).
[0097] FIG. 11 is a health assessment flowchart according to an embodiment. The health assessment flow 1100 includes, for example, the following steps: an estimated AHI acquisition step (S1110), a severity acquisition step (S1120), and an output step (S1130).
[0098] (4) Estimation of AHI The health information evaluation module 413 of the management server 103 estimates the AHI using an AHI estimation model (S1110). The health information evaluation module 413 obtains AH information from the auxiliary storage device 402 and inputs this AH information into the AHI estimation model M to obtain an estimated AHI as an output.
[0099] FIG. 13 is a graph showing the relationship between the AH information obtained based on the pulse wave information according to an embodiment and the manual AHI obtained based on the all-night sleep polysomnography information. The curve in the figure is the result of regression analysis (polynomial regression) for each data. Although the relationship between the AH information and the manual AHI can be fitted with a quadratic function, the variation becomes larger in the region where the manual AHI is higher, and it can be said that there is a limit to regressing the complex pattern of the manual AHI.
[0100] Figure 14 is a graph showing the relationship between the estimated AHI according to one embodiment and the manual AHI obtained based on overnight polysomnography information. As shown in Figure 14, a high linear relationship is observed between the estimated AHI and the manual AHI. Therefore, it can be confirmed that even when using AH event information acquired by the wearable device 101 and simplified by simple processing, an estimated AHI with a high correlation to the manual AHI can be obtained.
[0101] (5) Severity level acquisition process Next, the post-processing module 415 of the management server 103 obtains the severity of AHI based on the estimated AHI according to pre-set conditions (S1120). In other words, the severity of AHI is the result of evaluating the respiratory state during sleep and is an example of a sleep health assessment result. The post-processing module 415 can obtain, for example, four different AHI severity levels, a to d, based on the following conditions. a. Estimated AHI<5: Normal breathing b. Estimated AHI < 15: Mild obstructive sleep apnea c. 15 ≤ Estimated AHI < 30: Moderate obstructive sleep apnea d. Estimated AHI ≤ 30: Severe obstructive sleep apnea
[0102] The health management module 412 of the management server 103 stores (outputs) information regarding the severity of acquired AHI (sleep health assessment results) to the auxiliary storage device 402 (S1130). The health management module 412 of the management server 103 also works in cooperation with the health management module 312 of the user terminal 102 to display a screen showing the severity of AHI (sleep health assessment results) on the display of the user terminal 102 (S1130).
[0103] Specifically, the health management module 412 transmits information regarding the severity of AHI (for example, one of the pieces of information a to d representing the severity of AHI) to the user terminal 102 as a result of a sleep health assessment. The health management module 312 of the user terminal 102 records the received information regarding the severity of AHI in the auxiliary storage device 302. The health management module 312 also displays a health management display screen showing the severity of AHI on the user terminal 102's display based on the received information regarding the severity of AHI.
[0104] Figure 15 shows an example of a health management display screen (partial) according to one embodiment. The health management module 312 displays, for example, one of four pre-prepared health management display screens corresponding to the severity of the AHI, which corresponds to the severity of the user's AHI. Figure 15(A) is an example screen showing that the sleep health assessment result is "normal breathing," (B) is an example screen showing that the sleep health assessment result is "mild obstructive sleep apnea," and (C) is an example screen showing that the sleep health assessment result is "severe obstructive sleep apnea."
[0105] The health management module 312 displays a message 1510 representing the results of the sleep health assessment on each health management display screen. In addition, the health management module 312 also displays blood oxygen concentration fluctuation information 1520 on screens indicating that the sleep health assessment result is "mild" to "severe" obstructive sleep apnea. Specifically, the health management module 312 obtains AH event information for the corresponding date and time from the auxiliary storage device 402 and displays the number of AH events that occurred during sleep in chronological order based on this AH event information.
[0106] The health management module 312 can, for example, associate AH event information with a pre-set format, thereby displaying the number of AH events as a bar graph or the like for each first time interval. The health management module 312 can, for example, change the display format of the bars according to the number of AH events occurring per first time period. The health management module 312 displays the bars in the graph in a way that emphasizes them as the number of AH events per first time period increases. For example, bars can be displayed in a brighter color or a darker color as the number of AH events increases. Furthermore, while AH event information is recorded at first intervals (e.g., every 5 minutes), the health management module 312 may display the number of AH events during sleep at longer intervals than the first interval, such as every third interval (e.g., every 10 minutes).
[0107] In this technology, AH event information consists of approximately 96 time-event occurrence counts, for example, if the first time period is 5 minutes and the sleep time is 8 hours. Similarly, sleep-wake information consists of approximately 480 time-flag information, for example, if the predetermined period is 1 minute and the sleep time is 8 hours. Therefore, even when AH event information is sent from the wearable device 101 to the user terminal 102 in conjunction with the user's awakening, a smaller amount of data can be transmitted in a shorter time, while reducing power consumption. As a result, even a small wearable device 101, such as a ring, with limited battery capacity, can monitor the user's health status during sleep at high frequencies of 25Hz or 12.5Hz, enabling health management and highly accurate health assessment during sleep.
[0108] (6) Adjusting the AHI estimation model The model tuning module 416 of the management server 103 can tune the AHI estimation model M as needed. The tuning of the AHI estimation model M may be called additional training, fine tuning, transfer training, or the like.
[0109] The model adjustment module 416 acquires polysomnography (PSG) information for use in additional training and manual AHI based on this PSG information. The PSG information is typically high-resolution PSG information based on a high-resolution PSG examination, but may also be simplified PSG information from a simplified PSG examination. The PSG information includes manual AHI, pulse wave information, and respiratory pattern information.
[0110] This information may be obtained, for example, by the administrator of the management server 103, or it may be obtained from medical institutions, data banks, etc. When an administrator acquires the data, for example, they can have the subject wear a polysomnography device and a ring-shaped wearable device 101, and acquire biometric information using each device. One example of a data bank is PhysioNet (https: / / physionet.org / about / ).
[0111] The model adjustment module 416, for example, works in cooperation with the preprocessing module 414 to perform steps (1) to (3) above based on the pulse wave information and respiratory pattern information from the acquired PSG information, and obtains adjustment AH information. Then, using the adjustment AH information as input and the corresponding manual AHI as output, the AHI estimation model M is further trained. This enables AHI estimation and health assessment during sleep with higher accuracy.
[0112] The health management module 412 may be configured to manage information related to the user's health in addition to the sleep health management related to AHI described above. Specifically, the health management module 412 may, for example, work in conjunction with the health management module 312 of the user terminal 102 to acquire biometric information obtained from the user terminal 102 by the wearable device 101. The health management module 412 also analyzes the acquired biometric information using volumetric plethysmography and calculates at least one piece of health management information, such as heart rate, heart rate variability, blood oxygen saturation, blood pressure, and blood glucose level. The health management module 412 may also be configured to calculate the user's posture and displacement, activity level, calories burned, steps taken, behavioral discrimination, body temperature (skin temperature and core temperature), skin moisture content and sweating, blood glucose level, electrocardiogram, heart rate, heart rate variability, respiratory rate, and other health management information based on the acquired biometric information. The health management information may include management indicators for disease prevention, defined as necessary, such as a vascular health index, activity level, stress level, depression level, and lifestyle-related disease risk. Furthermore, the health management module 412 may use data obtained from various biological signals such as displacement, body temperature, heart rate, heart rate variability, and respiratory rate to perform analysis, evaluation, etc., on any health item. The health management module 412 outputs (stores) the calculated health management information to, for example, the health management information 420 in the auxiliary storage device 402 for management.
[0113] Furthermore, the health management module 412, for example, works in conjunction with the health management module 312 of the user terminal 102 to output (display) the calculated health management information on the display of the user terminal 102 (an example of an output device 305).
[0114] The health management module 412 may also be configured to notify the health management module if it finds any specific characteristics in the calculated health management information. The notification method is not particularly limited and may include, for example, displaying the information on the display of the user terminal 102, or sending an email or message to a designated recipient.
[0115] The above describes specific examples of the present technology, but these are merely illustrative and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes to the specific examples illustrated above. For example, the above examples are described in detail to make the present invention easier to understand, and are not necessarily limited to those having all the configurations described. Furthermore, it is possible to replace parts of the configuration of one embodiment with other configurations, and it is also possible to add other configurations to the configuration of one embodiment. In addition, it is possible to add, delete, or replace parts of the configuration of each embodiment.
[0116] This technology provides a program for executing each step of the sleep health evaluation method described above in the wearable device 101, the user terminal 102, and the management server 103. This program is stored, for example, in the main memory of the wearable device 101, the user terminal 102, and the management server 103. By executing this program, the processors of the wearable device 101, the user terminal 102, and the management server 103 can utilize the services of the AHI estimation system 100.
[0117] In this embodiment, the above preprocessing is performed by the preprocessing module 214 of the wearable device 101. That is, the preprocessing module is not an essential component in the user terminal 102 or the management server 103. However, the processing performed by the preprocessing module 214 of the wearable device 101 may be provided by the preprocessing modules of the user terminal 102 or the management server 103. Similarly, the main entity performing the processing in the above embodiment is not limited to that shown in the above embodiment, and may be performed by the wearable device 101, the user terminal 102, or the management server 103.
[0118] Furthermore, in the above embodiment, the processing performed by one module may be performed by other modules. Alternatively, the processing performed by one module may be performed by multiple different modules.
[0119] Furthermore, each of the above configurations, functions, processing units, and processing means may be implemented in hardware, either partially or entirely, by designing them as integrated circuits, for example. Alternatively, each of the above configurations and functions may be implemented in software by having the processor interpret and execute programs that implement each function. Information such as programs, tables, and files that implement each function can be stored in memory, a recording device such as a hard disk or SSD (Solid State Drive), or a recording medium such as an IC card, SD card, or DVD.
[0120] Furthermore, in diagrams showing the hardware configuration, only control lines and information lines deemed necessary for explanation are shown, and not all control lines and information lines are necessarily shown in the actual product. In reality, it can be assumed that almost all components are interconnected. Furthermore, the above-described embodiments disclose at least the configuration described in the claims. The claims shall include at least the following features: [Explanation of symbols]
[0121] 100…AHI estimation system, 101…wearable device, 102…user terminal, 211…executor module, 212…health management module, 213…health information evaluation module, 214…preprocessing module, 411…executor module, 412…health management module, 413…health information evaluation module, 414…preprocessing module, 415…postprocessing module, 416…model adjustment module
Claims
1. An AH information acquisition unit acquires pulse wave information over time from a living organism and, based on the pulse wave information, acquires AH information indicating the percentage of time during which the living organism experiences apnea (A) and hypopnea (H) during sleep. Based on the AH information, an AHI estimation unit estimates the Apnea-Hypopnea Index (AHI), An AHI estimation system equipped with [the following features].
2. The AH information acquisition unit is, Acquire acceleration sensor information, Based on acceleration sensor information, the system evaluates whether the organism is in a sleep state or an awake state. When the organism is evaluated to be in a sleep state, the AH information is acquired based on the pulse wave information at the time the organism was evaluated to be in a sleep state. The AHI estimation system according to claim 1.
3. The AH information acquisition unit is, Based on the pulse wave information, SpO2 information indicating the transcutaneous arterial blood oxygen saturation (SpO2) of the living body is obtained. Based on the SpO2 information, AH event information is obtained that indicates the number of times an apnea-hypopnea event occurs per unit time in which SpO2 falls below a predetermined threshold. Based on the AH event information, the AH information is acquired. The AHI estimation system according to claim 1.
4. The AH information acquisition unit is, Based on the first average SpO2 value, which is the average of SpO2 over a first time period calculated from the SpO2 information, the predetermined threshold value for that first time period is set. During the first time period, it is evaluated whether the second mean SpO2 value, which is the average of the SpO2 values over a second time period shorter than the first time period, is smaller than the predetermined threshold. When the second mean SpO2 value is smaller than the predetermined threshold, the number of apnea-hypopnea events is measured, The number of events occurring per unit time measured is output as the AH event information. The AHI estimation system according to claim 3.
5. The AHI estimation unit is, Using a machine learning model trained to take AH information, which indicates the percentage of time during sleep when the organism experiences apnea (A) and hypopnea (H) based on the organism's overnight polysomnography information, as input, and to output manual AHI obtained by an overnight polysomnography examination based on the overnight polysomnography information, The AH information acquisition unit is configured to estimate the AHI based on the AH information it has acquired. The AHI estimation system according to claim 1.
6. A second overnight polysomnography data and a second manual AHI obtained by an overnight polysomnography examination based on the second overnight polysomnography data are obtained. Based on the second overnight polysomnography information, the AH information is acquired. The system further comprises a model adjustment unit configured to additionally train the machine learning model so that it takes AH information obtained based on the second overnight polysomnography information as input and outputs the second manual AHI. The AHI estimation system according to claim 5.
7. The system further includes a symptom evaluation unit that evaluates the severity of sleep apnea syndrome in the living organism based on the estimated AHI and outputs information indicating the evaluated severity. The AHI estimation system according to claim 1.
8. Time-series pulse wave information is acquired from the living organism, and based on the pulse wave information, AH information is acquired indicating the percentage of time during which the living organism experiences apnea (A) and hypopnea (H) during sleep. Based on the aforementioned AH information, the Apnea-Hypopnea Index (AHI) is estimated. A method for estimating AHI, including the following.
9. A program for causing a computer to perform each step of the AHI estimation method described in claim 8.
10. A wearable device comprising a pulse wave sensor and a control unit, The control unit, By acquiring pulse wave information over time from the living body, Based on the pulse wave information, AH information is obtained that indicates the proportion of time during which the body experiences apnea (A) and hypopnea (H) during sleep. A wearable device configured in such a way.
11. The wearable device is a ring device that can be worn on a person's finger. The wearable device according to claim 10.
12. A method for controlling a wearable device comprising a pulse wave sensor and a control unit, The pulse wave sensor acquires pulse wave information from the living body over time. Based on the pulse wave information, AH information is obtained that indicates the proportion of time during which the body experiences apnea (A) and hypopnea (H) during sleep. method.
13. A program for causing a computer to perform each step of the method for controlling the wearable device described in claim 12.