Test kits and methods for detecting mild cognitive impairment

Abstract

To provide a technique to test mild cognitive impairment by olfactometry.SOLUTION: A subject can be diagnosed as having mild cognitive impairment by olfactory tests each using butter-like flavor liquid, toothpaste-like flavor liquid, and Indian ink-like flavor liquid.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a test kit and a test method for testing the presence or absence of mild cognitive impairment.

Background Art

[0002] In recent years, as the aging society progresses further, the number of dementia patients is on the rise. Moreover, Japan is also promoting a national policy called the Dementia Strategy Promotion Outline and needs to address dementia as a social issue. In such a situation, there is no specific medicine for dementia, and prevention is more important than treatment. Also, since it has been found that the progression of dementia can be suppressed by early preventive intervention, it is very meaningful to be able to grasp the risk at a stage earlier than when clinical symptoms such as cognitive decline begin to appear.

[0003] In the process of developing dementia, it is known to go through a precursor state called mild cognitive impairment (MCI). Mild cognitive impairment is a symptom between normal and dementia, with memory loss but no impairment in daily life. It is not a condition that elderly people necessarily develop and is also observed in relatively young middle-aged people. Also, if mild dementia develops, it does not necessarily progress to dementia, and there are people who recover from mild dementia to the normal level. Therefore, taking appropriate measures against mild cognitive impairment before it progresses to dementia is effective in preventing dementia, and for this purpose, it is important to test for the presence or absence of mild cognitive impairment.

[0004] Conventionally, various reports have been made on methods for testing mild cognitive impairment. For example, Patent Document 1 reports that mild cognitive impairment can be tested using the concentration of HMGB1 in a biological sample as an index. Also, Patent Document 2 describes that mild cognitive impairment can be tested using the expression level of a specific miRNA in a biological sample as an index. However, the methods described in Patent Documents 1 and 2 require biological samples such as plasma and cerebrospinal fluid, are invasive tests, and have the drawback of imposing a large burden on the subject. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2020-204554 [Patent Document 2] Japanese Patent Publication No. 2017-46659 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Since dementia is associated with a decline in olfactory function, it is known that olfactory testing can be used to screen for the presence or absence of dementia. However, it has not been known to be possible to screen for mild cognitive impairment through olfactory testing, and furthermore, it has not been clarified what kind of scents should be selected to determine the presence or absence of mild cognitive impairment through olfactory testing.

[0007] Therefore, the object of the present invention is to provide a technique for testing mild cognitive impairment using olfactory testing. [Means for solving the problem]

[0008] The inventors of the present invention conducted diligent research to solve the aforementioned problems and discovered that by selecting a combination of butter, toothpaste, and ink scents from among the many existing scents and performing an olfactory test using these scents, it is possible to determine the presence or absence of mild cognitive impairment. Furthermore, they discovered that by combining the above three scents with at least one scent from among apple, cypress, and soap scents and performing an olfactory test, it is possible to determine the presence or absence of mild cognitive impairment with even greater accuracy. The present invention was completed by further research based on these findings.

[0009] In other words, the present invention provides inventions in the following embodiments. Item 1. A kit for testing for the presence or absence of mild cognitive impairment based on cognitive function level, A test kit containing butter-flavored liquid, toothpaste-flavored liquid, and ink-flavored liquid as fragrance solutions for olfactory testing. Item 2. The test kit according to Item 1, further comprising, as a fragrance liquid for olfactory testing, at least one fragrance liquid selected from the group consisting of apple fragrance liquid, cypress fragrance liquid, and soap fragrance liquid. Item 3. The test kit described in Item 1, further comprising apple-flavored liquid, cypress-flavored liquid, and soap-flavored liquid as fragrance solutions for olfactory testing. Item 4. A test kit as described in any of items 1-3, which includes a response sheet for the subject to report the results of the olfactory test. Item 5. A method for testing mild cognitive impairment based on cognitive function level, comprising performing an olfactory test using butter-flavored liquid, toothpaste-flavored liquid, and ink-flavored liquid. Item 6. The testing method according to Item 5, further comprising performing an olfactory test using at least one fragrance liquid selected from the group consisting of apple fragrance liquid, cypress fragrance liquid, and soap fragrance liquid. Item 7. The testing method described in Item 5, further comprising performing an olfactory test using apple fragrance liquid, cypress fragrance liquid, and soap fragrance liquid. Item 8. A testing method described in any of items 5 to 7, wherein a score is assigned to each fragrance liquid according to the correctness of the answer, and the sum of these scores is used as the test index. Item 9. The testing method described in Item 7, wherein the score corresponding to the correctness of the answer for each fragrance liquid used is set to satisfy the following ratio, and the sum of these scores is used as the test index. <Percentage of scores based on the correctness of the answer> <Percentage of scores based on the correctness of the answer> • Olfactory test of butter-flavored liquid: 2 for correct answer, -3 to 0 for incorrect answer. • Toothpaste fragrance liquid: 0.25-4 if correct, -3-0 if incorrect. • Ink-based fragrance solution: 0.25-4 if correct, -3-0 if incorrect. Apple fragrance liquid: 0.25-4 if correct, -3-0 if incorrect. • Hinoki fragrance liquid: 0.25-4 if correct, -3-0 if incorrect. • Soap fragrance liquid: 0.25-4 if correct, -3-0 if incorrect. [Effects of the Invention]

[0010] According to the test kit and test method of the present invention, it is possible to accurately test for the presence or absence of mild cognitive impairment through a non-invasive olfactory test, thereby enabling efficient screening of individuals at risk of developing dementia. [Modes for carrying out the invention]

[0011] 1. Mild cognitive impairment testing kit The present invention provides a test kit for determining whether or not a person has mild cognitive impairment, and is characterized by containing a butter-flavored liquid, a toothpaste-flavored liquid, and an ink-flavored liquid as olfactory testing solutions. The present invention provides a detailed description of the test kit below.

[0012] [Fragrance liquid for olfactory testing] The present invention's testing kit includes a butter-flavored liquid, a toothpaste-flavored liquid, and an ink-flavored liquid as fragrance liquids for olfactory testing. By performing olfactory testing using each of these three fragrance liquids, it becomes possible to test for the presence or absence of mild cognitive impairment.

[0013] Butter-flavored liquid is a flavoring liquid that exhibits an aroma reminiscent of butter. Those skilled in the art can prepare butter-flavored liquid using known flavoring components and known blending methods. For example, butter-flavored liquid can be prepared by blending with flavoring components such as δ-decalactone, acetaldehyde, methylbutanone, and heptanal as the main components. Furthermore, butter-flavored liquid may consist only of flavoring components, or it may contain, in addition to flavoring components, solvents such as water, paraffinic hydrocarbons, monohydric lower alcohols, and polyhydric alcohols; additives such as surfactants and solubilizers. The content of flavoring components in butter-flavored liquid is not particularly limited as long as it can exhibit an aroma reminiscent of butter, but examples include 0.001 to 100% by weight. From the viewpoint of further improving the accuracy of mild cognitive impairment tests, the content of flavoring components in butter-flavored liquid is preferably 0.001 to 10% by weight, more preferably 0.005 to 1.0% by weight.

[0014] A toothpaste fragrance solution is a fragrance solution that exhibits a scent reminiscent of toothpaste. Those skilled in the art can prepare a toothpaste fragrance solution using known fragrance components and known fragrance blending techniques. For example, a toothpaste fragrance solution can be prepared by blending fragrance components such as carvone, mint oil, menthofuran, menthol, menthone, menthyl acetate, pulegone, and rotundiphorone as the main components. Furthermore, a toothpaste fragrance solution may consist solely of fragrance components, or it may contain, in addition to fragrance components, water, solvents such as paraffinic hydrocarbons, monohydric lower alcohols, and polyhydric alcohols; additives such as surfactants and solubilizers. The content of fragrance components in a toothpaste fragrance solution is not particularly limited, as long as it exhibits a scent reminiscent of toothpaste, but examples include 0.001 to 100% by weight. From the viewpoint of further improving the accuracy of testing for mild cognitive impairment, the content of fragrance components in the toothpaste fragrance solution is preferably 0.001 to 10% by weight, and more preferably 0.005 to 5.0% by weight.

[0015] An ink-scented fragrance liquid is a fragrance liquid that exhibits a fragrance reminiscent of ink. A person skilled in the art can prepare an ink-scented fragrance liquid by using known fragrance components and known perfume-making techniques. For example, an ink-scented fragrance liquid can be prepared by perfuming with a fragrance component such as borneol as the main component. Also, an ink-scented fragrance liquid may be composed only of fragrance components, or in addition to the fragrance components, solvents such as water, paraffin hydrocarbons, monohydric lower alcohols, polyhydric alcohols, etc.; additives such as surfactants and solubilizers may also be included. Regarding the content of the fragrance components in the ink-scented fragrance liquid, there is no particular limitation as long as it can exhibit a fragrance reminiscent of ink. For example, 0.0005 to 100% by weight can be mentioned. From the viewpoint of further improving the inspection accuracy of mild cognitive impairment, the content of the fragrance components in the ink-scented fragrance liquid is preferably 0.001 to 10% by weight, more preferably 0.001 to 1% by weight.

[0016] In the inspection kit of the present invention, in addition to the above three types of fragrance liquids, at least one type of fragrance liquid among an apple-scented fragrance liquid, a cypress-scented fragrance liquid, and a soap-scented fragrance liquid may be further included. By performing an olfactory test using at least one type of fragrance liquid among an apple-scented fragrance liquid, a cypress-scented fragrance liquid, and a soap-scented fragrance liquid together with the above three types of fragrance liquids, it becomes possible to more accurately inspect the presence or absence of mild cognitive impairment. In particular, by performing an olfactory test using a total of six types of fragrance liquids, each of which combines the above three types of fragrance liquids with an apple-scented fragrance liquid, a cypress-scented fragrance liquid, and a soap-scented fragrance liquid, it is possible to extremely accurately inspect the presence or absence of mild cognitive impairment.

[0017] An apple flavor liquid is a flavor liquid that exhibits a scent reminiscent of apples. A person skilled in the art can prepare an apple flavor liquid using known flavor components and known flavoring techniques. For example, an apple flavor liquid can be prepared by flavoring using one or more flavor components such as 2-(tert-butyl) cyclohexyl acetate, allyl heptanoate, ethylene brassylate, hexyl acetate, hexanol, hexanal, trans-2-hexenal, ethyl butyrate, butyl acetate, butyl butyrate, etc. as the main components. Also, the apple flavor liquid may be composed only of flavor components, or in addition to the flavor components, solvents such as water, paraffin hydrocarbons, monohydric lower alcohols, polyhydric alcohols, etc.; additives such as surfactants and solubilizers may be included. Regarding the content of the flavor components in the apple flavor liquid, there is no particular limitation as long as it can exhibit a scent reminiscent of apples, but for example, 0.001 to 100% by weight can be mentioned. From the viewpoint of further improving the inspection accuracy of mild cognitive impairment, the content of the flavor components in the apple flavor liquid is preferably 0.01 to 50% by weight, more preferably 0.02 to 10% by weight.

[0018] A cypress flavor liquid is a flavor liquid that exhibits a scent reminiscent of cypress. A person skilled in the art can prepare a cypress flavor liquid using known flavor components and known flavoring techniques. For example, a cypress flavor liquid can be prepared by flavoring using one or more flavor components such as α-cedrene, cedrol, thujopsene, hinokitiol, α-pinene, etc. as the main components. Also, the cypress flavor liquid may be composed only of flavor components, or in addition to the flavor components, solvents such as water, paraffin hydrocarbons, monohydric lower alcohols, polyhydric alcohols, etc.; additives such as surfactants and solubilizers may be included. Regarding the content of the flavor components in the cypress flavor liquid, there is no particular limitation as long as it can exhibit a scent reminiscent of cypress, but for example, 0.001 to 100% by weight can be mentioned. From the viewpoint of further improving the inspection accuracy of mild cognitive impairment, the content of the flavor components in the cypress flavor liquid is preferably 0.005 to 50% by weight, more preferably 0.005 to 10% by weight.

[0019] A soap-based fragrance liquid is a fragrance liquid that exhibits a scent reminiscent of soap. Those skilled in the art can prepare a soap-based fragrance liquid using known fragrance components and known fragrance blending techniques. For example, a soap-based fragrance liquid can be prepared by blending one or more fragrance components from among methyl dihydrojasmonate, phenyl alcohol, 2-phenylethanol, geraniol, nerol, citronellol, aldehydes, etc., as the main component. Furthermore, a soap-based fragrance liquid may consist solely of fragrance components, or it may contain, in addition to fragrance components, solvents such as water, paraffinic hydrocarbons, monohydric lower alcohols, and polyhydric alcohols; additives such as surfactants and solubilizers. The content of fragrance components in a soap-based fragrance liquid is not particularly limited, as long as it exhibits a scent reminiscent of soap, but examples include 0.001 to 100% by weight. From the viewpoint of further improving the accuracy of testing for mild cognitive impairment, the content of fragrance components in the soap fragrance solution is preferably 0.001 to 10% by weight, and more preferably 0.002 to 1.0% by weight.

[0020] The test kit of the present invention may further, if necessary, include at least one of the following fragrance liquids for olfactory testing: vanilla ice cream fragrance liquid, sweaty sock fragrance liquid, mandarin orange fragrance liquid, and coffee fragrance liquid.

[0021] A vanilla ice cream fragrance liquid is a fragrance liquid that exhibits a scent reminiscent of vanilla ice cream. Those skilled in the art can prepare a vanilla ice cream fragrance liquid using known fragrance components and known fragrance blending methods. For example, a vanilla ice cream fragrance liquid can be prepared by blending fragrance components such as vanillin as the main component. A vanilla ice cream fragrance liquid may consist only of fragrance components, or it may contain, in addition to fragrance components, water, solvents such as paraffinic hydrocarbons, monohydric lower alcohols, and polyhydric alcohols; additives such as surfactants and solubilizers. The content of fragrance components in a vanilla ice cream fragrance liquid is not particularly limited as long as it can exhibit a scent reminiscent of vanilla ice cream, but for example, it can be 0.001 to 100% by weight, preferably 0.002 to 10% by weight, and more preferably 0.02 to 10% by weight.

[0022] A "steamy sock fragrance liquid" is a fragrance liquid that exhibits a scent reminiscent of sweaty socks. Those skilled in the art can prepare a steamy sock fragrance liquid using known fragrance components and known fragrance blending methods. For example, a steamy sock fragrance liquid can be prepared by blending fragrance components such as isovaleric acid as the main component. A steamy sock fragrance liquid may consist only of fragrance components, or it may contain, in addition to fragrance components, water, solvents such as paraffinic hydrocarbons, monohydric lower alcohols, and polyhydric alcohols; additives such as surfactants and solubilizers. The content of fragrance components in a steamy sock fragrance liquid is not particularly limited as long as it can exhibit a scent reminiscent of sweaty socks, but for example, it can be 0.001 to 100% by weight, preferably 0.005 to 25% by weight, and more preferably 0.05 to 5.0% by weight.

[0023] A mandarin orange fragrance liquid is a fragrance liquid that exhibits a scent reminiscent of mandarin oranges. Those skilled in the art can prepare a mandarin orange fragrance liquid using known fragrance components and known fragrance blending methods. For example, a mandarin orange fragrance liquid can be prepared by blending fragrance components such as D-limonene, myrcene, α-pinene, and linalool as the main components. A mandarin orange fragrance liquid may consist only of fragrance components, or it may contain, in addition to fragrance components, water, solvents such as paraffinic hydrocarbons, monohydric lower alcohols, and polyhydric alcohols; additives such as surfactants and solubilizers. The content of fragrance components in a mandarin orange fragrance liquid is not particularly limited as long as it can exhibit a scent reminiscent of mandarin oranges, but for example, it can be 0.001 to 100% by weight, preferably 0.05 to 50% by weight, and more preferably 0.1 to 10.0% by weight.

[0024] A coffee-flavored liquid is a flavoring liquid that exhibits an aroma reminiscent of coffee. Those skilled in the art can prepare a coffee-flavored liquid using known flavoring components and known blending methods. For example, a coffee-flavored liquid can be prepared by blending flavoring components such as methylcyclopentenolone, furfural, vanillin, and furfuryl mercaptan as the main components. A coffee-flavored liquid may consist only of flavoring components, or it may contain, in addition to the flavoring components, water, solvents such as paraffinic hydrocarbons, monohydric lower alcohols, and polyhydric alcohols; additives such as surfactants and solubilizers. The content of the flavoring components in the coffee-flavored liquid is not particularly limited as long as it can exhibit an aroma reminiscent of mandarin oranges, but for example, it can be 0.00 to 100% by weight, preferably 0.002 to 10% by weight, and more preferably 0.0025 to 5.0% by weight.

[0025] In one embodiment of the test kit of the present invention, the fragrance liquid is provided in a spray container (such as a spray bottle), a dropper container, or an application container (such as a pen-type container). When the fragrance liquid is provided in one of these containers, the fragrance liquid contained in the container is sprayed, dropped, or applied to the substrate to be scented, thereby scenting the substrate and performing an olfactory test. That is, in the test kit of the present invention, if the fragrance liquid is contained in a spray container, a dropper container, or an application container, the test kit of the present invention may also include a substrate to be scented. In the test kit of this embodiment, the amount of fragrance liquid contained in the container may be the amount used for one test, or it may be the amount used for two or more tests. Furthermore, in the test kit of this embodiment, the amount of fragrance liquid sprayed, dropped, or applied to the substrate to be scented is not particularly limited as long as it is sufficient to impart the fragrance of each fragrance liquid to the substrate, and can be appropriately set according to the composition of the fragrance liquid used, for example, 10 to 1000 μl, preferably 50 to 500 μl, and more preferably 100 to 400 μl. Furthermore, the material of the substrate to be scented is not particularly limited as long as it can be scented by the fragrance liquid, for example, paper, nonwoven fabric, woven fabric, knitted fabric, plastic, etc. Furthermore, the shape of the substrate to be scented is not particularly limited as long as it can be used for olfactory testing, for example, sheet-shaped, cup-shaped, block-shaped, sponge-shaped, etc.

[0026] In another embodiment of the test kit of the present invention, the fragrance liquid can be provided in a sealed container having an opening that can be opened and closed. When the fragrance liquid is provided in a sealed container, the olfactory test can be performed by opening the container and smelling the fragrance emitted from the opening. In the test kit of this embodiment, the amount of fragrance liquid contained in the container is not particularly limited as long as the fragrance of each fragrance liquid is present when the opening is opened, but for example, it can be 10 to 1000 μl, preferably 50 to 500 μl, and more preferably 100 to 400 μl.

[0027] In yet another embodiment of the test kit of the present invention, the fragrance liquid can be provided sealed in a state impregnated with a substrate such as paper, nonwoven fabric, woven fabric, knitted fabric, filter paper, sponge, or gel. When the fragrance liquid is provided impregnated with the substrate, an olfactory test can be performed by taking out the substrate impregnated with the fragrance liquid and smelling its scent. In the test kit of this embodiment, the amount of fragrance liquid to be impregnated with the substrate is not particularly limited as long as the fragrance of each fragrance liquid is exhibited, but for example, 10 to 1000 μl, preferably 50 to 500 μl, and more preferably 100 to 400 μl per substrate is possible.

[0028] [Methods of olfactory testing] By performing an olfactory test for each fragrance liquid using the fragrance liquid included in the test kit of the present invention, the cognitive function level is evaluated and the presence or absence of mild cognitive impairment is determined.

[0029] In the olfactory test using the test kit of the present invention, the subject is asked to smell each fragrance liquid in any order and to report the scents they perceived. The subject's response may be in a free format without being given answer choices, but it is preferable to provide multiple answer choices and have the subject select from them.

[0030] When asking for answers in a multiple-choice format, for example, in addition to the correct scent option, one or more (e.g., three) dummy options for incorrect scents, an option for "I don't know," and an option for "None of these" should be presented. From the perspective of more accurately determining whether or not a person has mild cognitive impairment, the following are examples of options to use when asking for answers in a multiple-choice format: In the case of butter-flavored liquid, in addition to the correct answer "butter," five options should be presented: "urea," "cinnamon," "apple," "I don't know," and "None of these." In the case of toothpaste-flavored liquid, five options should be presented: in addition to the correct answer "toothpaste," five options should be presented: "sewage," "wasabi," "rubber," "I don't know," and "None of these." In the case of ink-flavored liquid, five options should be presented: in addition to the correct answer "ink," five options should be presented: "miso," "curry," "sweat odor," "I don't know," and "None of these." For apple-flavored liquid, you should present a total of five options: the correct answer "apple," plus "cypress," "soil," "garlic," "I don't know," and "None of these." For cypress-flavored liquid, you should present a total of five options: the correct answer "cypress," plus "curry," "coffee," "garlic," "I don't know," and "None of these." For soap-flavored liquid, you should present a total of five options: the correct answer "soap," plus "food waste," "garlic," "adhesive," "I don't know," and "None of these." For vanilla ice cream-flavored liquid, you should present a total of five options: the correct answer "vanilla ice cream," plus "peppermint," "garlic," "body odor," "I don't know," and "None of these." For the case of a sweaty sock fragrance liquid, you should present a total of five options: the correct answer "sweaty socks," plus "tatami mat," "soy sauce," "rose," "I don't know," and "none of these." For the case of a mandarin orange fragrance liquid, you should present a total of five options: the correct answer "mandarin orange," plus "incense stick," "household gas," "curry," "I don't know," and "none of these."In the case of coffee-flavored liquid, you would need to present a total of five options: the correct answer "coffee," plus "incense sticks," "food waste," "rubber," "I don't know," and "none of these."

[0031] Furthermore, when conducting an olfactory test and requiring multiple-choice answers, before presenting multiple options, it may be helpful to first ask whether or not the testee perceives any scent, and only then, if they answer that they perceive any scent, present them with multiple options to choose from.

[0032] The test kit of the present invention may include an answer sheet for answering the results of the olfactory test in order to improve convenience by making it easy to collect the subjects' responses. If the answer sheet is in an open-ended format, it is sufficient to have a section for free-response answers for each fragrance liquid used. If the answer sheet is in a multiple-choice format, it is sufficient to have options provided for each fragrance liquid used.

[0033] In an olfactory test using the test kit of the present invention, the olfactory test may be performed using multiple fragrance liquids in succession. However, in order to prevent olfactory habituation, a break of several minutes may be taken between each olfactory test using one fragrance liquid. Alternatively, after performing olfactory tests using several fragrance liquids in succession, a break of several minutes may be taken before performing olfactory tests using several more fragrance liquids in succession.

[0034] [Method for determining whether or not one has mild cognitive impairment] Based on the results of the olfactory test using the test kit of the present invention, the level of cognitive function is evaluated to determine whether or not there is mild cognitive impairment.

[0035] In the testing method using the test kit of the present invention, the presence or absence of mild cognitive impairment can be determined using the accuracy rate of the olfactory test (the ratio of the number of fragrance liquids correctly identified to the total number of fragrance liquids tested) as an indicator. A higher accuracy rate in the olfactory test indicates a higher level of cognitive function, while a lower accuracy rate indicates a lower level of cognitive function. Based on the assessed level of cognitive function, the presence or absence of mild cognitive impairment is determined. However, since the ability to distinguish between the presence or absence of mild cognitive impairment varies depending on the type of fragrance liquid used, it is desirable that the determination of the presence or absence of mild cognitive impairment in the testing method using the test kit of the present invention be based on setting a score for each fragrance liquid used according to the correctness of the answer, and using the sum of these scores as an indicator.

[0036] For example, a suitable example is to set the score assigned based on the correctness of the answers to the olfactory test for each fragrance liquid to satisfy the ratio shown in Table 1 (hereinafter sometimes referred to as "score gradient pattern A"), and use the sum of these scores as an indicator to determine whether or not there is mild cognitive impairment.

[0037] [Table 1]

[0038] In particular, in the aforementioned score gradient pattern A, by using a combination of three fragrance liquids—apple-flavored liquid, cypress-flavored liquid, and soap-flavored liquid—as additional fragrance liquids, and using the sum of the scores as an indicator, it becomes possible to determine the presence or absence of mild cognitive impairment with even greater accuracy. Table 2 below shows the ratio of scores (score gradient pattern A') assigned according to the correctness of the answers to each olfactory test when the three fragrance liquids—apple-flavored liquid, cypress-flavored liquid, and soap-flavored liquid—are combined as additional fragrance liquids in the aforementioned score gradient pattern A.

[0039] [Table 2]

[0040] Another suitable example is to set the scores assigned based on the correctness of the answers to the olfactory test for each fragrance liquid to satisfy the ratio shown in Table 3 (hereinafter sometimes referred to as "score gradient pattern B"), and use the sum of these scores as an indicator for determining the presence or absence of mild cognitive impairment.

[0041] [Table 3]

[0042] In particular, in the score gradient pattern B, by using a combination of three fragrance liquids—apple-flavored liquid, cypress-flavored liquid, and soap-flavored liquid—as additional fragrance liquids, and using the sum of the scores as an indicator, it becomes possible to determine the presence or absence of mild cognitive impairment with even greater accuracy. Table 4 below shows the ratio of scores (score gradient pattern B') assigned according to the correctness of the answers to each olfactory test when the three fragrance liquids—apple-flavored liquid, cypress-flavored liquid, and soap-flavored liquid—are combined as additional fragrance liquids in the score gradient pattern B.

[0043] [Table 4]

[0044] In the testing method using the testing kit of the present invention, when determining the presence or absence of mild cognitive impairment using the accuracy rate of the olfactory test as an indicator, a higher accuracy rate indicates a lower probability of suffering from mild cognitive impairment, while a lower accuracy rate indicates a higher probability of suffering from mild cognitive impairment.

[0045] In the testing method using the testing kit of the present invention, if a score is set for each fragrance liquid used according to the correctness of the answer, as in the score gradient patterns A, A', B, and B', it can be determined that the higher the total score, the lower the possibility of suffering from mild cognitive impairment, and the lower the total score, the higher the possibility of suffering from mild cognitive impairment.

[0046] Furthermore, since the accuracy rate or score of the olfactory test may vary even for the same subject depending on the combination of fragrance liquids used in the test kit of the present invention, the intensity of the fragrance liquids, and the method of olfactory testing, it is desirable to first conduct olfactory tests using the test kit to be actually used on several healthy individuals who have been confirmed not to have mild cognitive impairment, and several individuals who have been diagnosed with mild cognitive impairment, and to obtain their respective accuracy rates or scores. It is also desirable to set a cutoff value (a boundary value that distinguishes healthy individuals from those with mild cognitive impairment) for the accuracy rate or score between healthy individuals and those with mild cognitive impairment using ROC (receiver operating characteristic curve) analysis. By setting a cutoff value in this way, it becomes possible to easily determine whether or not a subject has mild cognitive impairment based on their accuracy rate or score. Furthermore, by using the actual test kit to conduct olfactory tests on multiple individuals who have already been diagnosed with dementia and determining their accuracy rate or score, and by setting a cutoff value (a boundary value to distinguish between individuals with mild cognitive impairment and those with dementia) for the accuracy rate or score of individuals with mild cognitive impairment and those with dementia using ROC analysis, it becomes possible to determine whether a subject has mild cognitive impairment or dementia if they are determined not to be a healthy individual.

[0047] By using the test kit of the present invention, the presence or absence of mild cognitive impairment can be tested with high accuracy. For example, in one embodiment of a test method using the test kit of the present invention, where six types of fragrance liquids—butter fragrance liquid, toothpaste fragrance liquid, ink fragrance liquid, apple fragrance liquid, cypress fragrance liquid, and soap fragrance liquid—are used and the total score is calculated according to the score gradient pattern A', it becomes possible to distinguish between healthy individuals and individuals with mild cognitive impairment with high accuracy in ROC analysis between healthy individuals and individuals with mild cognitive impairment, with an area under the curve (AUC) of 0.75 or higher; a sensitivity of 65% or higher, preferably 70% or higher, more preferably 74% or higher; and a specificity of 60% or higher, preferably 65% ​​or higher, more preferably 69% or higher. Furthermore, in one embodiment of a testing method using the testing kit of the present invention, in which six types of fragrance liquids—butter fragrance liquid, toothpaste fragrance liquid, ink fragrance liquid, apple fragrance liquid, cypress fragrance liquid, and soap fragrance liquid—are used and the total score is calculated according to the score gradient pattern A', it becomes possible to distinguish between individuals with mild cognitive impairment and dementia patients with high accuracy, as shown by the ROC analysis between individuals with mild cognitive impairment and dementia patients, with an AUC of 0.80 or higher; a sensitivity of 65% or higher, preferably 70% or higher, more preferably 76% or higher; and a specificity of 60% or higher, preferably 70% or higher, more preferably 75% or higher, and even more preferably 79% or higher.

[0048] 2. Testing methods for mild cognitive impairment The present invention relates to a method for testing for the presence or absence of mild cognitive impairment, and is characterized by comprising the step of performing an olfactory test using a butter-flavored liquid, a toothpaste-flavored liquid, and an ink-flavored liquid.

[0049] The present invention relates to a testing method for determining whether or not a person suffers from mild cognitive impairment using the aforementioned testing kit. The composition of the butter-flavored liquid, toothpaste-flavored liquid, and ink-flavored liquid, the types and compositions of other fragrance liquids used as needed, the olfactory testing method, and the method for determining whether or not a person suffers from mild cognitive impairment based on the olfactory testing results are as described in section "1. Testing Kit for Mild Cognitive Impairment". [Examples]

[0050] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0051] Test example ·subject The study included 100 healthy individuals, 61 individuals with mild cognitive impairment (MCI), and 62 individuals with Alzheimer's disease (AD).

[0052] The 100 healthy individuals were those who scored 28 points or higher on the MMSE (Mini-mental State Examination).

[0053] The 61 individuals with MCI had an MMSE score of 24 to 27 and were diagnosed with mild cognitive impairment with memory impairment by a dementia specialist based on the diagnostic criteria of Petersen et al. (Petersen RC: Mild cognitive impairment as a diagnostic entity. J. Intern. Med. 2004; 256(3): 183-194.).

[0054] The 62 individuals with Alzheimer's disease (AD) had an MMSE score of 23 or less and were diagnosed with Alzheimer's disease by a dementia specialist based on one of the following criteria: ICD-10 (International Classification of Diseases-10), DSM-5 (Diagnostic and Statistical Manual of Mental Disorders-5), or NIA-AA (National Institute on Aging and Alzheimer's Association).

[0055] • Preparation of fragrance liquid We prepared fragrance liquids exhibiting various scents with the following compositions (20 types in total, 10 different scent types). Note that fragrance liquid B contains 10 to 454 times the amount of fragrance compared to fragrance liquid A, which contains the same fragrance. • Butter-flavored liquid A: A flavoring liquid containing 0.01% by weight of a butter-flavoring component (containing δ-decalactone), exhibiting a buttery scent. • Butter-flavored liquid B: A flavoring liquid containing 0.5% by weight of a butter-flavoring component (containing δ-decalactone), exhibiting a buttery scent. • Toothpaste fragrance solution A: A fragrance solution containing 0.01% by weight of toothpaste fragrance components (containing carvone), exhibiting the scent of toothpaste. • Toothpaste-like fragrance liquid B: A fragrance liquid containing 2.5% by weight of toothpaste-like fragrance components (containing carvone), exhibiting the scent of toothpaste. • Ink-flavored fragrance liquid A: A fragrance liquid containing 0.001% by weight of an ink-flavored fragrance component (containing borneol), exhibiting the scent of ink. • Ink-flavored fragrance liquid B: A fragrance liquid containing 0.1% by weight of an ink-flavored fragrance component (containing borneol), exhibiting the scent of ink. • Apple-flavored liquid A: A fragrance liquid containing 0.04% by weight of apple-flavored components (containing 2-(tert-butyl)cyclohexyl acetate, allyl heptanoate, ethylene brassirate, and hexyl acetate), exhibiting an apple scent. • Apple-flavored liquid B: A fragrance liquid containing 5.0% by weight of apple-flavored components (containing 2-(tert-butyl)cyclohexyl acetate, allyl heptanoate, ethylene brassirate, and hexyl acetate), exhibiting an apple scent. • Soap-flavored liquid A: A fragrance liquid containing 0.00)% by weight of soap-like fragrance components (containing methyl dihydrojasmonate and phenyl alcohol), exhibiting a soap scent. • Soap-flavored liquid B: A fragrance liquid containing 0.12% by weight of soap-like fragrance components (containing methyl dihydrojasmonate and phenyl alcohol), exhibiting a soap scent. • Hinoki-flavored liquid A: A fragrance liquid containing 0.011% by weight of hinoki-flavored fragrance components (containing α-cedrene, cedrol, and thujopsene), exhibiting the scent of hinoki. • Hinoki-flavored liquid B: A fragrance liquid containing 5.0% by weight of hinoki-flavored components (containing α-cedrene, cedrol, and thujopsene) that exhibits the scent of hinoki. • Vanilla Ice Cream Fragrance Liquid A: A fragrance liquid containing 0.02% by weight of vanilla ice cream-flavored ingredients (containing vanillin), exhibiting the scent of vanilla ice cream. • Vanilla Ice Cream Fragrance Liquid B: A fragrance liquid containing 5.0% by weight of vanilla ice cream-flavored ingredients (containing vanillin), exhibiting the scent of vanilla ice cream. • Sultry Sock Fragrance Liquid A: A fragrance liquid containing 0.1% by weight of a scent component resembling sweaty socks (containing isovaleric acid), exhibiting the scent of sweaty socks. • Sultry Sock Fragrance Liquid B: A fragrance liquid containing 2.5% by weight of a scent component resembling sweaty socks (containing isovaleric acid), exhibiting the scent of sweaty socks. • Mandarin Orange Fragrance Liquid A: A fragrance liquid containing 0.5% by weight of mandarin orange fragrance components (containing limonene) that exhibits the scent of mandarin oranges. • Mandarin Orange Fragrance Liquid B: A fragrance liquid containing 5.0% by weight of mandarin orange fragrance (containing limonene), exhibiting the scent of mandarin oranges. • Coffee-flavored liquid A: A flavoring liquid containing 0.0025% by weight of a coffee-flavoring component (containing methylcyclopentenolone), exhibiting a coffee aroma. • Coffee-flavored liquid B: A flavoring liquid containing 1.0% by weight of a coffee-flavoring component (containing methylcyclopentenolone) that exhibits the aroma of coffee.

[0056] • Olfactory test First, scented paper cups were prepared by spraying the aforementioned fragrance liquid twice into a 95ml paper cup, thereby adhering approximately 300μl of the fragrance liquid to the cup. Scented paper cups were prepared for each of the 20 types of fragrance liquids.

[0057] Five test sequence patterns P to T, as shown in Table 5, were prepared, and a randomly selected test sequence pattern was assigned to each subject. According to the assigned test sequence pattern, scented paper cups (paper cups with fragrance liquid A) numbered 1 to 10 were arranged on a table, and subjects were asked to smell the scents in the order of test sequence 1 to 5 and respond. After a 2-minute break to prevent olfactory habituation, subjects were asked to smell the scents in the order of test sequence 6 to 10 and respond. A 5-minute break was then taken to prevent olfactory habituation. Next, according to the assigned test sequence pattern, scented paper cups (paper cups with fragrance liquid B) numbered 11 to 20 were arranged on a table, and subjects were asked to smell the scents in the order of test sequence 11 to 15 and respond. After a 2-minute break to prevent olfactory habituation, subjects were asked to smell the scents in the order of test sequence 16 to 20 and respond.

[0058] Each time a participant smelled a scented paper cup, they were asked whether or not they perceived any scent. If they answered that they perceived some scent, they were shown options A through F, which were set for each fragrance liquid as shown in Table 6, and were asked to indicate which of A through F the scent they perceived corresponded to.

[0059] [Table 5]

[0060] [Table 6]

[0061] ·result Table 7 shows the average percentage of participants who correctly identified the scents (correct response rate) in a test using 20 different fragrance solutions for healthy individuals, those with MCI, and those with AD. When comparing fragrance solution A, which had a lower fragrance concentration, with fragrance solution B, which had a higher fragrance concentration, fragrance solution B tended to have a higher correct response rate. However, the difference in correct response rates between MCI and healthy individuals, and between MCI and AD, showed the same trend for fragrance solution A and fragrance solution B. Furthermore, in the test using 20 different fragrance solutions, the correct response rate was highest for healthy individuals, followed by MCI, and then AD.

[0062] However, for toothpaste-flavored liquid, butter-flavored liquid, and ink-flavored liquid, the difference in correct response rates between MCI and healthy individuals was larger compared to other fragrance liquids. Furthermore, the difference in correct response rates between MCI and AD was large for toothpaste-flavored liquid, butter-flavored liquid, and ink-flavored liquid, and the difference between MCI and AD was particularly pronounced for ink-flavored liquid. In addition, for apple-flavored liquid, cypress-flavored liquid, and soap-flavored liquid, the difference in correct response rates between MCI individuals was relatively large, and the difference in correct response rates between MCI and AD was also large. From these results, it became clear that by conducting olfactory tests using toothpaste-flavored liquid, butter-flavored liquid, and ink-flavored liquid, it is possible to distinguish between MCI and healthy individuals, and between MCI and AD, and thus enable the diagnosis of MCI. Furthermore, it was found that by performing olfactory tests using apple-flavored liquid, cypress-flavored liquid, and soap-flavored liquid in addition to the aforementioned fragrance liquid, MCI can be tested with greater accuracy.

[0063] [Table 7]

[0064] Next, ROC analysis was performed to examine the accuracy of the test when multiple fragrance solutions were combined. Specifically, based on the results of 10 fragrance solutions B with high fragrance concentrations, a score of 1 point was assigned for each correct identification of one fragrance solution B. ROC analysis was performed using the total score for each combination of fragrance solutions shown in Tables 8 and 9, and the AUC (Area Under the Curve), cutoff value, sensitivity, and specificity of the ROC curve were determined. SAS (release 9.4) (SAS Institute Japan Co., Ltd.) was used for the ROC analysis, and the cutoff value was calculated using the Youden Index method. The results are shown in Tables 8 and 9. When the test results of fragrance solutions exhibiting the scents of toothpaste, butter, and ink were combined, the AUC and sensitivity in the ROC analysis were high and the specificity was low between MCI and healthy individuals, and between MCI and AD. This indicates that it is possible to distinguish between MCI and healthy individuals, and between MCI and AD, enabling highly accurate testing for MCI. In particular, it was confirmed that the accuracy of MCI testing is further improved by performing olfactory tests using at least one of the following: apple-flavored liquid, cypress-flavored liquid, and soap-flavored liquid, in addition to toothpaste-flavored liquid, butter-flavored liquid, and ink-flavored liquid, especially by combining these four types.

[0065] [Table 8]

[0066] [Table 9]

[0067] As described above, by scoring each correct answer for a single fragrance solution as 1 point and performing ROC analysis, it was confirmed that olfactory tests using toothpaste fragrance solution, butter fragrance solution, ink fragrance solution, apple fragrance solution, cypress fragrance solution, and soap fragrance solution were particularly effective in diagnosing MCI with high accuracy. Next, the test accuracy when the six fragrance solutions were combined was examined using ROC analysis, with the points awarded for correct answers for each fragrance solution being replaced as shown in Table 10. The results are shown in Table 11. As a result, it was found that the accuracy of MCI testing improved further when the points awarded for correct answers for each fragrance solution were scored, as in score gradient patterns A' and B'. In particular, it was confirmed that the accuracy of MCI testing increased dramatically when scoring according to score gradient pattern A'.

[0068] [Table 10]

[0069] [Table 11]

Claims

1. A kit for testing whether a person is likely to be a healthy individual, have mild cognitive impairment, or have dementia, based on their cognitive function level. A test kit containing butter-flavored liquid, toothpaste-flavored liquid, ink-flavored liquid, and soap-flavored liquid as fragrance solutions for olfactory testing.

2. Furthermore, the test kit according to claim 1 includes, as a fragrance liquid for olfactory testing, at least one fragrance liquid selected from the group consisting of apple fragrance liquid and cypress fragrance liquid.

3. Furthermore, the test kit according to claim 1 further includes apple-flavored liquid and cypress-flavored liquid as fragrance liquids for olfactory testing.

4. A test kit according to any one of claims 1 to 3, comprising a response sheet for a subject to report the results of an olfactory test.

5. A method for obtaining test indices to assess whether a person is likely to be a healthy individual, a person with mild cognitive impairment, or a patient with dementia, based on their cognitive function level, The process includes a step of conducting an olfactory test using butter-flavored liquid, toothpaste-flavored liquid, ink-flavored liquid, and soap-flavored liquid. The aforementioned test indicator is the sum of the scores or the correct answer rate for the olfactory test. The aforementioned score is set according to the correctness of the answer for each fragrance liquid used in the olfactory test.

6. The method according to claim 5, further comprising performing an olfactory test using at least one fragrance liquid selected from the group consisting of apple fragrance liquid and cypress fragrance liquid.

7. Furthermore, the method according to claim 5, wherein an olfactory test is performed using apple-flavored liquid and cypress-flavored liquid.

8. The method according to any one of claims 5 to 7, wherein the test index is the sum of the scores.

9. The method according to claim 7, wherein a score is set for each fragrance liquid according to the correctness of the answer, so as to satisfy the following ratio, and the sum of these scores is used as an inspection index. <Percentage of scores based on the correctness of the answers> - Olfactory test of butter-flavored liquid: 2 for correct answer, -3 to 0 for incorrect answer. • Toothpaste fragrance liquid: 0.25 to 4 if correct, -3 to 0 if incorrect. - Ink-based fragrance solution: 0.25 to 4 if correct, -3 to 0 if incorrect. Apple-flavored liquid: 0.25 to 4 if correct, -3 to 0 if incorrect. - Hinoki fragrance liquid: 0.25 to 4 if correct, -3 to 0 if incorrect. • Soap fragrance liquid: 0.25 to 4 if correct, -3 to 0 if incorrect.

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