Blood lipid index detection system and method

Abstract

The present invention provides a blood lipid index detection system and method based on photoplethysmogram signals. The method includes at least two annular devices, and the two annular devices are configured to be respectively fixed on the ankle artery and the brachial artery of a user for acquiring target photoplethysmogram signals of the ankle artery and the brachial artery of the user. Wherein, the annular device includes a photodetector and a processing circuit. The photodetector is used for acquiring the photoplethysmogram signals of the ankle artery and the brachial artery of the user, and the processing circuit is electrically connected to the photodetector for processing the photoplethysmogram signals into target photoplethysmogram signals and sending them; and a terminal device, which is communicatively connected to the annular device and is configured to receive the target photoplethysmogram signals from the annular device and obtain the blood lipid index of the user based on the target photoplethysmogram signals.

Description

Technical Field

[0001] The present invention relates to the technical field of blood lipid detection, and particularly to a blood lipid index detection system and method. Background Art

[0002] Currently, the detection of blood lipid indices mainly adopts invasive or minimally invasive means. For example, testing institutions generally use the method of collecting blood from the forearm. Such methods have a large needle puncture wound area, require fasting blood collection, poor timeliness, and high cost, and are difficult to meet the daily detection needs. Although the household minimally invasive blood lipid detector has a small needle puncture wound, due to easy extrusion, blood cells are deformed, the blood lipid concentration is easily affected by tissue fluid dilution, and the test strip enzyme is also easily contaminated. As a result, the detection efficiency is low, the detection equipment is large in size, and it is easily affected by detection conditions. Summary of the Invention

[0003] To at least partially overcome at least one of the above-mentioned technical defects or other inventions, at least one embodiment of the present invention provides a blood lipid index detection system and method, which can improve the detection efficiency, are easy to wear and fix on the measured part, and can ensure the stability of detection conditions.

[0004] According to one aspect of the present invention, there is provided a blood lipid index detection system based on a photoplethysmogram signal, including: at least two annular devices, the two annular devices being configured to be respectively fixed on the ankle artery and brachial artery of a user for obtaining target photoplethysmogram signals of the ankle artery and brachial artery of the user, wherein the annular device includes a photodetector and a processing circuit, the photodetector is used for obtaining the photoplethysmogram signals of the ankle artery and brachial artery of the user, the processing circuit is electrically connected to the photodetector for processing the photoplethysmogram signals into target photoplethysmogram signals and sending them; and a terminal device, communicatively connected to the annular device, configured to receive the target photoplethysmogram signals from the annular device and obtain the blood lipid indices of the user based on the target photoplethysmogram signals.

[0005] According to an embodiment of the present disclosure, the annular device further includes: a light emitting unit configured to emit a light beam to the ankle artery and brachial artery of the user, the light beam being reflected by the ankle artery and the brachial artery and received by the photodetector, the photodetector converting the optical signal of the light beam into the photoplethysmogram signal, wherein the optical signal changes with the contraction or dilation of the blood vessel at the annular device, and the peaks and valleys of the photoplethysmogram signal respectively correspond to the contraction and dilation of the blood vessel; and a power supply unit electrically connected to the light emitting unit for supplying power to the light emitting unit.

[0006] According to an embodiment of the present disclosure, the processing circuit includes: a first circuit module electrically connected to the photodetector, and the first circuit module performs at least noise reduction processing, filtering processing, and signal amplification processing on the photoplethysmogram signal; a second circuit module electrically connected to the first circuit module, and the second circuit module is configured to convert the target photoplethysmogram signal processed by the first circuit module from an analog signal to a digital signal; and a communication module, electrically connected to the second circuit module and communicatively connected to the terminal device, for sending the digital signal converted by the second circuit module to the terminal device.

[0007] According to an embodiment of the present disclosure, the terminal device obtains the brachial-ankle pulse wave velocity and the timing information of the target photoplethysmogram signal based on the target photoplethysmogram signal, and obtains the parameter index of blood lipid by inputting the brachial-ankle pulse wave velocity, the timing information, and the basic information of the user into a pre-trained blood lipid model.

[0008] According to an embodiment of the present disclosure, the terminal device calculates the brachial-ankle pulse wave velocity based on time difference data, a first path distance, and a second path distance, where the time difference data represents the time difference for obtaining the photoplethysmogram signals of the ankle artery and the brachial artery, the first path distance represents the path distance from the user's heart to the ankle, and the second path distance represents the path distance from the user's heart to the upper arm, and the first path distance and the second path distance are determined by the height data of the user.

[0009] According to an embodiment of the present disclosure, the timing information includes at least one of the peak-peak time difference and the peak-valley time difference corresponding to the characteristic waveband of the target photoplethysmogram signal, where the characteristic waveband of the target photoplethysmogram signal includes at least one of a main peak, a secondary peak, a main valley, and a secondary valley.

[0010] According to an embodiment of the present disclosure, the terminal device further includes a display unit for displaying at least one of the blood lipid index, the target photoplethysmogram signal, and the timing information.

[0011] According to an embodiment of the present disclosure, the blood lipid index includes at least one of the triglyceride content and the lipoprotein cholesterol content.

[0012] According to an embodiment of the present disclosure, the training method of the pre-trained blood lipid model includes: obtaining a test set, where the test set includes the target photoplethysmogram signals of the ankle artery and the brachial artery of multiple target objects, the timing information of the target photoplethysmogram signal, and the invasive blood lipid information parameters; and inputting the training set into a support vector machine regression model to obtain the pre-trained blood lipid model.

[0013] Embodiments of another aspect of the present disclosure provide a method for detecting blood lipid indicators by applying the above system, including: obtaining target photoplethysmogram signals of the ankle artery and brachial artery of a user; and obtaining the blood lipid indicators of the user based on the target photoplethysmogram signals.

[0014] According to an embodiment of the present disclosure, a blood lipid indicator detection system obtains photoplethysmogram signals of the ankle artery and brachial artery of a user through a photodetector of an annular device, processes the photoplethysmogram signals into target photoplethysmogram signals through a processing circuit and sends them to a terminal device, and the terminal device calculates the blood lipid indicators of the user. In this process, no invasive operation is required and no pressure detection is required for the user. Since the photoplethysmogram signal is an optical signal, embodiments of the present disclosure can obtain blood lipid indicators through the optical signal, thereby improving the detection efficiency. The annular device has a simple structure and a small volume, is easy to wear and fix on the measured part, and can ensure the stability of the detection conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a structural block diagram of a blood lipid indicator detection system based on a photoplethysmogram signal according to a schematic embodiment of the present disclosure;

[0016] Figure 2 is a schematic diagram of the connection relationship of each device in the annular device of a blood lipid indicator detection system based on a photoplethysmogram signal according to a schematic embodiment of the present disclosure;

[0017] Figure 3 is a cross-sectional view of the annular device of a blood lipid indicator detection system based on a photoplethysmogram signal fixed on the ankle artery or brachial artery of a user according to a schematic embodiment of the present disclosure;

[0018] Figure 4 is a structural schematic diagram of the annular device of a blood lipid indicator detection system based on a photoplethysmogram signal according to a schematic embodiment of the present disclosure; and

[0019] Figure 5 is a flowchart of a method for detecting blood lipid indicators by applying the above system according to a schematic embodiment of the present disclosure.

[0020] DESCRIPTION OF THE REFERENCE NUMERALS

[0021] 100: Annular device;

[0022] 101: Photodetector;

[0023] 102: Processing circuit;

[0024] 1021: First circuit module;

[0025] 1022: The second circuit module;

[0026] 1023: The communication module;

[0027] 103: The light-emitting unit;

[0028] 104: The power supply unit;

[0029] 200: The terminal device. Detailed implementation manners

[0030] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following further elaborates on the present invention in detail with reference to specific embodiments and the accompanying drawings. However, the present invention can be implemented in different forms and should not be construed as being limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. In the drawings, for clarity, the dimensions and relative dimensions of layers and regions may be exaggerated, and the same reference numerals throughout the drawings denote the same elements.

[0031] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In the following detailed description, for the sake of explanation, numerous specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, it is obvious that one or more embodiments can also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts of the present invention.

[0032] The terms used herein are merely for the purpose of describing specific embodiments and are not intended to limit the present invention. The terms "including", "comprising", etc. used herein indicate the presence of the described features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0033] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0034] To facilitate the understanding of the technical solutions of the present invention by those skilled in the art, the following technical terms are now explained.

[0035] In the case of using expressions such as "at least one of A, B, and C, etc.", generally, it should be interpreted according to the meaning that those skilled in the art usually understand this expression (for example, "a system having at least one of A, B, and C" should include, but not be limited to, a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", generally, it should be interpreted according to the meaning that those skilled in the art usually understand this expression (for example, "a system having at least one of A, B, or C" should include, but not be limited to, a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0036] Figure 1 is a structural block diagram of a blood lipid index detection system based on a photoplethysmogram signal according to an exemplary embodiment of the present disclosure.

[0037] As Figure 1 shown, an embodiment of the present disclosure provides a blood lipid index detection system based on a photoplethysmogram signal, including at least two annular devices 100 and a terminal device 200.

[0038] The two annular devices 100 are configured to be respectively fixed on the ankle artery and the brachial artery of the user, and are used to acquire the target photoplethysmogram signals of the ankle artery and the brachial artery of the user. The terminal device 200 is communicatively connected to the annular device 100, and is configured to receive the target photoplethysmogram signals from the annular device 100, and obtain the blood lipid index of the user based on the target photoplethysmogram signals. Further, 4 annular devices 100 can be provided, and are respectively fixedly arranged on the ankle arteries and the brachial arteries on the left and right sides of the user.

[0039] According to an embodiment of the present disclosure, the annular device 100 may include a photodetector 101 and a processing circuit 102. The photodetector 101 can be used to acquire the photoplethysmogram signals of the ankle artery and the brachial artery of the user. The processing circuit 102 is electrically connected to the photodetector 101, and can be used to process the photoplethysmogram signals into target photoplethysmogram signals and send them. The photodetector 101 can select a broadband photodetector 101, for example, a silicon-based photodetector 101 and an indium gallium arsenide photodetector 101.

[0040] According to an embodiment of the present disclosure, the target photoplethysmogram signal can be the photoplethysmogram signals of the ankle artery and the brachial artery after being processed from the photoplethysmogram signals of the ankle artery and the brachial artery detected by the photodetector 101, and can be used for the terminal device 200 to obtain the blood lipid index of the user.

[0041] According to an embodiment of the present disclosure, the obtained blood lipid index is the blood lipid parameter information of the user, which can be used for real-time monitoring of the user's blood lipid index information and status. The health status of the user still needs to be judged by a doctor.

[0042] According to an embodiment of the present disclosure, the photoelectric detector 101 of the annular device 100 is used to obtain the photoplethysmogram signals of the user's ankle artery and brachial artery. The processing circuit 102 processes the photoplethysmogram signals into target photoplethysmogram signals and sends them to the terminal device 200. The terminal device 200 calculates the blood lipid index of the user. In this process, there is no need for invasive operation and no need to perform pressurized detection on the user. The blood lipid index can be obtained through optical signals, which can improve the detection efficiency. The annular device has a simple structure and a small volume, is easy to wear and fix on the measured part, and can ensure the stability of the detection conditions.

[0043] Figure 2 It is a schematic diagram of the connection relationship of each device in the annular device of the blood lipid index detection system based on the photoplethysmogram signal according to the schematic embodiment of the present disclosure;

[0044] Figure 3 It is a cross-sectional view of the annular device of the blood lipid index detection system based on the photoplethysmogram signal fixed on the user's ankle artery or brachial artery according to the schematic embodiment of the present disclosure.

[0045] As Figure 2 shown, according to an embodiment of the present disclosure, the annular device 100 further includes a light emitting unit 103 and a power supply unit 104.

[0046] The light emitting unit 103 is configured to emit a light beam to the user's ankle artery and brachial artery, as Figure 3As shown, the light beam is reflected by the ankle artery and / or the brachial artery and then received by the photodetector 101. The photodetector 101 converts the optical signal of the light beam into a photoplethysmogram signal. The optical signal changes with the contraction or dilation of the blood vessels at the annulus device 100. The peaks and valleys of the photoplethysmogram signal can respectively correspond to the contraction and dilation of the blood vessels. The light-emitting unit 103 can select a near-infrared light source or an infrared light source with a longer wavelength. When irradiating the user's skin, it can generate a smaller absorption amount and achieve deeper tissue penetration. For example, a laser, a light-emitting diode, etc. can be selected. Correspondingly, the cut-off wavelength of the photodetector 101 can be set to be greater than the peak wavelength of the light-emitting unit 103. The power supply unit 104 can be electrically connected to the light-emitting unit 103 to supply power to the light-emitting unit 103. The power supply unit 104 can select a regulated light source to achieve the function of voltage regulation. It can also be set that the power supply unit 104 and the light-emitting unit 103 are integrally designed, and the power supply unit 104 can be a component device of the light-emitting unit 103. The photodetector 101 and the light-emitting unit 103 can be integrally integrated adjacent to each other and can be encapsulated by a flexible material. The shape of the annulus device 100 is not limited. The annulus device 100 can use a flexible material to improve the comfort of the user during use. The annulus device 100 can be set as an adjustable structure for easy wearing by the user.

[0047] According to an embodiment of the present disclosure, the processing circuit 102 includes a first circuit module 1021, a second circuit module 1022, and a communication module 1023.

[0048] The first circuit module 1021 is electrically connected to the photodetector 101. The first circuit module 1021 can at least perform noise reduction processing, filtering processing, and signal amplification processing on the photoplethysmogram signal. The first circuit module 1021 can be composed of devices such as a crystal oscillator, a capacitor, a resistor, and a signal amplifier. After being processed by the first circuit module 1021, the photodetector 101 can detect a clearer waveform of the photoplethysmogram signal.

[0049] The second circuit module 1022 is electrically connected to the first circuit module 1021. The second circuit module 1022 is used to convert the target photoplethysmogram signal processed by the first circuit module 1021 from an analog signal into a digital signal. The second circuit module 1022 can be implemented by an analog-to-digital converter.

[0050] The communication module 1023 is electrically connected to the second circuit module 1022 and communicates with the terminal device 200, and can be used to send the digital signal converted by the second circuit module 1022 to the terminal device 200. The communication module 1023 can communicate with the terminal device 200 in a wired connection or a wireless connection manner, and different detection methods can be set according to different connection methods. The wireless connection can be realized through communication devices such as local area network and Bluetooth to communicate the processing circuit 102 with the terminal device 200. During use, the wireless connection is more convenient than the wired connection, and the wireless connection is less affected by signal interference than the wired connection.

[0051] Figure 4 It is a schematic structural diagram of an annular device of a blood lipid index detection system based on a photoplethysmogram signal according to an exemplary embodiment of the present disclosure.

[0052] The annular device 100 may further include a flexible substrate, which can be obtained by mixing and curing a polydimethylsiloxane (PDMS) main agent and a curing agent in a ratio of 10:1. As Figure 2 shown, between the light emitting unit 103 and the power supply unit 104 of the annular device 100, and between the processing circuit 102 and the photodetector 101, they can be connected by serpentine interconnecting wires. Further, it can also be set that the first circuit module 1021, the second circuit module 1022 and the communication module 1023 of the processing circuit 102 are connected by serpentine interconnecting wires. The serpentine interconnecting wires can be printed on the flexible substrate using a microelectronic printer. The light emitting unit 103, the power supply unit 104, the photodetector 101, the first circuit module 1021, the second circuit module 1022 and the communication module 1023 can be inverted and attached to the printed circuit through a chip inversion and sticking device. An organic polymer material with excellent light transmission performance can be selected to encapsulate each device in the annular device 100, so as to form a functional device with stable mechanical properties and signal transmission capabilities. As Figure 4 shown, after encapsulation, it can be installed together with an annular band formed by mold pouring. The annular band can be made of a flexible material so that the annular band has good tensile properties and is convenient for adapting to the use of different users.

[0053] According to an embodiment of the present disclosure, the terminal device 200 obtains the brachial-ankle pulse wave velocity and the timing information of the target photoplethysmogram signal based on the target photoplethysmogram signal, and by inputting the brachial-ankle pulse wave velocity, the timing information and the basic information of the user into a pre-trained blood lipid model, the parameter index of blood lipid is obtained.

[0054] According to an embodiment of the present disclosure, the timing information may include at least one of the peak-to-peak time difference and the peak-to-valley time difference corresponding to the characteristic band of the target photoplethysmogram signal. The characteristic band of the target photoplethysmogram signal includes at least one of a main peak, a secondary peak, a main valley, and a secondary valley. The basic information of the user may include the user's height, weight, age, etc.

[0055] According to an embodiment of the present disclosure, the terminal device 200 calculates the brachial-ankle pulse wave velocity based on the time difference data, the first path distance, and the second path distance. The time difference data represents the time difference for obtaining the photoplethysmogram signals of the ankle artery and the brachial artery. The first path distance represents the path distance from the user's heart to the ankle, and the second path distance represents the path distance from the user's heart to the upper arm. Among them, the first path distance and the second path distance are determined by the user's height data.

[0056] According to an embodiment of the present disclosure, the calculation formula for the brachial-ankle pulse wave velocity may be:

[0057] ba-PWV = (L a -L b ) / ΔT ba ;

[0058] where ba-PWV is the brachial-ankle pulse wave velocity, L a is the path distance from the user's heart to the ankle, L b is the path distance from the user's heart to the upper arm, and ΔT ba is the time difference for obtaining the photoplethysmogram signals of the ankle artery and the brachial artery.

[0059] According to an embodiment of the present disclosure, the path distance L a from the user's heart to the ankle can be calculated by the following formula: L a = 0.8192×H + 12.318, where H is the user's height in centimeters (cm).

[0060] According to an embodiment of the present disclosure, the path distance L b from the user's heart to the upper arm can be calculated by the following formula: L b = 0.2195×user height - 2.0734, where H is the user's height in centimeters (cm).

[0061] When calculating the brachial-ankle pulse wave velocity, the ΔT ba data with large fluctuations can be removed to improve the reliability of the calculation and reduce the influence caused by data fluctuations during signal acquisition.

[0062] According to an embodiment of the present disclosure, the terminal device 200 further includes a display unit, which can be used to display at least one of blood lipid indexes, target photoplethysmogram signals, and timing information. The blood lipid indexes may include at least one of triglyceride content and lipoprotein cholesterol content. The terminal device 200 may include a signal receiving function, a timing signal extraction function, and a numerical calculation function, and a pre-trained blood lipid model may be set on the terminal device 200. Various communication client applications may be installed on the terminal device 200, for example, shopping applications, web browser applications, search applications, instant messaging tools, email clients, and / or social platform software, etc. (only as examples). The terminal device 200 may be various electronic devices with a display screen and supporting web browsing, including but not limited to smart phones, tablet computers, laptop portable computers, and desktop computers, etc.

[0063] According to an embodiment of the present disclosure, the training method of the pre-trained blood lipid model includes: obtaining a test set, where the test set includes target photoplethysmogram signals of the ankle arteries and brachial arteries of multiple target objects, timing information of the target photoplethysmogram signals, brachial-ankle pulse wave velocity, and invasive blood lipid information parameters. Input the training set into a support vector regression model (Support Vector Regression, SVR) to obtain the pre-trained blood lipid model.

[0064] According to an embodiment of the present disclosure, the invasive blood lipid information parameters may include the height, weight, age, triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) content, etc. of the target object.

[0065] Preferably, the time difference between collecting the target photoplethysmogram signal and the invasive blood lipid information parameters may not be greater than 30 minutes.

[0066] The training set is used as the calculation parameters for machine learning modeling. The more target objects, the higher the accuracy of the final model establishment. By enriching the diversity of target object parameters, the stability and accuracy of the model can be improved. 80% of the data can be randomly selected from the test set as the training set for machine learning, and the remaining 20% can be used as the test set to verify the accuracy of the blood lipid model.

[0067] Figure 5 It is a flowchart of the method for detecting blood lipid indexes by applying the above system according to the schematic embodiment of the present disclosure. As Figure 5 shown, the training method includes operations S310 to S320.

[0068] In operation S310, obtain the target photoplethysmogram signals of the ankle arteries and brachial arteries of the user.

[0069] In operation S320, blood lipid indexes of the user are obtained based on the target photoplethysmogram signal.

[0070] According to an embodiment of the present disclosure, operation S310 may include the following operations.

[0071] The light emitting unit 103 emits a light beam to the ankle artery and brachial artery of the user. After being reflected by the ankle artery and brachial artery, the light beam can be received by the photodetector 101. After the photodetector 101 converts the optical signal of the light beam into a photoplethysmogram signal, the target photoplethysmogram signal can be obtained after being processed by the processing circuit 102.

[0072] According to an embodiment of the present disclosure, operation S320 may include the following operations.

[0073] The timing information of the target photoplethysmogram signal is extracted from the target photoplethysmogram signal and the brachial-ankle pulse wave velocity can be calculated. By inputting the brachial-ankle pulse wave velocity, the timing information and the basic information of the user into a pre-trained blood lipid model, the parameter indexes of blood lipid can be obtained.

[0074] Compared with the traditional inflatable cuff detection, by obtaining the target photoplethysmogram signal to obtain the blood lipid indexes of the user, it will not cause discomfort to the patient or leave indentations and has a wider range of users. Moreover, the target photoplethysmogram signal can extract various physiological signal parameters of the user, for example, the photoplethysmogram signal, the brachial-ankle pulse wave velocity and the blood lipid parameters.

[0075] It should also be noted that the directional terms mentioned in the embodiments, such as "upper", "lower", "front", "rear", "left", "right", etc., are only references to the directions in the drawings and are not used to limit the protection scope of the present invention. Throughout the drawings, the same elements are denoted by the same or similar reference numerals. When it may cause confusion in the understanding of the present invention, the conventional structures or configurations will be omitted, and the shapes and sizes of the components in the drawings do not reflect the actual sizes and proportions, but only illustrate the content of the embodiments of the present invention.

[0076] Unless otherwise known to the contrary, the numerical parameters in this specification and the appended claims are approximate values and can be changed according to the required characteristics obtained through the content of the present invention. Specifically, all the numbers representing the contents of the components, reaction conditions, etc. used in the specification and the claims should be understood to be modified by the term "about" in all cases. Generally, the meaning expressed is that it includes a change of ±10% in some embodiments, a change of ±5% in some embodiments, a change of ±1% in some embodiments, and a change of ±0.5% in some embodiments.

[0077] The ordinal terms used in the description and claims, such as "first", "second", "third", etc., are used to modify the corresponding elements. They do not in themselves imply any ordinal number for the elements, nor do they represent the order of one element relative to another or the order in the manufacturing method. The use of these ordinal terms is only to clearly distinguish an element with a certain name from another element with the same name.

[0078] In addition, unless specifically described or steps that must occur in sequence, the order of the above steps is not limited to that listed above and can be varied or rearranged according to the required design. And based on considerations of design and reliability, the above embodiments can be used in combination with each other or in combination with other embodiments, that is, the technical features in different embodiments can be freely combined to form more embodiments.

[0079] The above specific embodiments have further elaborated on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A blood lipid index detection system based on photoplethysmogram signals, characterized in that Comprising: At least two annular devices, the two annular devices being configured to be respectively fixed on the ankle artery and the brachial artery of the user for acquiring target photoplethysmogram signals of the ankle artery and the brachial artery of the user. Wherein, the annular device includes a photodetector and a processing circuit, the photodetector is used for acquiring the photoplethysmogram signals of the ankle artery and the brachial artery of the user, and the processing circuit is electrically connected to the photodetector for processing the photoplethysmogram signals into target photoplethysmogram signals and sending them; and A terminal device, communicatively connected to the annular device, configured to receive the target photoplethysmogram signals from the annular device. The terminal device obtains the brachial-ankle pulse wave velocity and the timing information of the target photoplethysmogram signals based on the target photoplethysmogram signals, and obtains the parameter indexes of blood lipids by inputting the brachial-ankle pulse wave velocity, the timing information and the basic information of the user into a pre-trained blood lipid model; Wherein, the training method of the pre-trained blood lipid model includes: Obtaining a test set, the test set including target photoplethysmogram signals of the ankle artery and the brachial artery of a plurality of target objects, the timing information of the target photoplethysmogram signals, and invasive blood lipid information parameters; and Inputting the training set into a support vector machine regression model, wherein the training set is obtained based on the test set.

2. The system according to claim 1, characterized in that The annular device further includes: A light emitting unit, configured to emit a light beam to the ankle artery and the brachial artery of the user. The light beam is reflected by the ankle artery and the brachial artery and then received by the photodetector. The photodetector converts the optical signal of the light beam into the photoplethysmogram signal. Wherein, the optical signal changes with the contraction or dilation of the blood vessel at the annular device, and the peaks and valleys of the photoplethysmogram signal respectively correspond to the contraction and dilation of the blood vessel; and A power supply unit, electrically connected to the light emitting unit, for supplying power to the light emitting unit.

3. The system according to claim 1, characterized in that The processing circuit includes: A first circuit module, electrically connected to the photodetector, the first circuit module performing at least noise reduction processing, filtering processing and signal amplification processing on the photoplethysmogram signal; A second circuit module, electrically connected to the first circuit module, the second circuit module being used for converting the target photoplethysmogram signal processed by the first circuit module from an analog signal to a digital signal; and A communication module, electrically connected to the second circuit module and communicatively connected to the terminal device, for sending the digital signal converted by the second circuit module to the terminal device.

4. The system according to claim 1, characterized in that The terminal device calculates the brachial-ankle pulse wave velocity based on time difference data, a first path distance, and a second path distance, where the time difference data represents the time difference for obtaining photoplethysmogram signals of the ankle artery and the brachial artery, the first path distance represents the path distance from the user's heart to the ankle, and the second path distance represents the path distance from the user's heart to the upper arm, and the first path distance and the second path distance are determined by the user's height data.

5. The system according to claim 1, characterized in that The timing information includes at least one of the peak-to-peak time difference and the peak-to-valley time difference corresponding to the characteristic wavelength band of the target photoplethysmogram signal, where the characteristic wavelength band of the target photoplethysmogram signal includes at least one of a main peak, a secondary peak, a main valley, and a secondary valley.

6. The system according to claim 1, characterized in that The terminal device further includes a display unit for displaying at least one of the blood lipid index, the target photoplethysmogram signal, and the timing information.

7. The system according to claim 1, characterized in that The blood lipid index includes at least one of the triglyceride content and the lipoprotein cholesterol content.

8. A method for detecting blood lipid indexes by using the system according to any one of claims 1-7, characterized in that Comprising: Obtaining target photoplethysmogram signals of the ankle artery and the brachial artery of the user; And Obtaining the blood lipid index of the user based on the target photoplethysmogram signal.

Images