Suggestions on the ideal method of conducting community screenings for older adults.

BACKGROUND/OBJECTIVES: Since dementia and frailty lead to a reduced quality of life and risk of needing long-term care in the older adults, we hypothesized that evaluations related to dementia and frailty would be useful and of high interest in screening for the older adults. Therefore, we conducted a community screening incorporating multiple simple evaluations related to dementia and frailty. In addition to various functional evaluations, we investigated interest in tests, thoughts on the disease, and the relationships between subjective (i.e., how one feels about oneself) and objective evaluations (i.e., the results of tests and rating scales). The purpose of this study was to examine the thoughts regarding tests and diseases and the functions that make it difficult to accurately perceive changes by oneself, and to obtain suggestions on the ideal method of community screening for the older adults. SUBJECTS/METHODS: The participants were 86 people aged 65 and over living in Kotoura Town who participated in the community screening, for which we obtained background information and body measurements. We also assessed physical, cognitive and olfactory function, evaluated nutritional status, and we administered a questionnaire (interest in tests, thoughts on dementia and frailty, and a subjective functional evaluation). RESULTS: Regarding interest in tests, the participants answers were highest for physical, cognitive and olfactory function, in that order (68.6%, 60.5%, and 50.0%, respectively). In the survey on thoughts on dementia and frailty, 47.6% of participants felt that people with dementia were viewed with prejudice, and 47.7% did not know about frailty. Regarding the relationship between subjective and objective evaluations, only the assessment of cognitive function did not show a correlation between both evaluations. CONCLUSIONS: From the viewpoint of the participants' degree of interest in and the need for accurate evaluations through objective examination, the findings suggest that the assessment of physical and cognitive function may be beneficial as a screening tool for older adults. Objective evaluation is essential, particularly for assessing cognitive function. However, approximately half the participants believed people with dementia were viewed with prejudice and did not know about frailty, which may lead to barriers to testing and low interest. The importance of increasing the participation rate in community screening through disease-related educational activities was suggested.

Validation of a novel computerized cognitive function test for the rapid detection of mild cognitive impairment.

BACKGROUND: In the present study, we examined the distinguishing ability of a mild cognitive impairment (MCI) assessment tool for rapid screening using a computer (MARC) for Alzheimer's disease dementia (ADD), MCI, and non-demented controls (NDC) with no cognitive impairment, as well as its validity and reliability, as part of a preliminary trial for the development of the tool. METHODS: A total of 64 participants (23 in the ADD group, 17 in the MCI group, and 24 in the NDC group) were analyzed. The participants were administered MARC and a pre-existing computerized Alzheimer's dementia screening test (MSP), and 31 participants (14 in the MCI group, 17 in the NDC group) were readministered MARC within 4 months from the first test. RESULTS: The median (interquartile range) test time for MARC was 401 (350-453) s. Total MARC scores were significantly worse in the MCI and ADD groups than in the NDC group (p < 0.05 and p < 0.01, respectively). In the receiver operating characteristic (ROC) analysis, the area under the ROC curve (AUC) when comparing the NDC and MCI groups was 0.866 (95% CI, 0.759-0.974), when comparing the NDC and AD groups was 0.989 (95% CI, 0.970-1.000), and when comparing the MCI and AD groups was 0.889 (95% CI, 0.790-0.988). Furthermore, there was a significant correlation with the results of the existing test, MSP (r = 0.839, p < 0.001). In addition, the intraclass correlation coefficient (ICC) (1,1) when the first and second MARC scores were compared was 0.740 (95% CI, 0.529-0.865; p < 0.001). CONCLUSIONS: MARC is considered capable of distinguishing MCI with high accuracy. The tool has good validity and reliability, and it can be administered in a short period of time without the need for a specialist.

Association between frequency of going out and mild cognitive impairment in community-dwelling older adults: a pilot study in frailty prevention groups.

BACKGROUND: Clarifying the role of physical limitations in the relationship between frequency of going out and mild cognitive impairment (MCI) may be useful in supporting early detection and prevention of MCI. However, few studies have explored relatively active populations that are continuously active throughout the year. This study aimed to determine the relationship between frequency of going out and MCI among non-homebound older adults who participated in group activities to prevent frailty. METHODS: This prospective cohort study used frequency of going out as the exposure and MCI as the outcome. The Touch Panel-type Dementia Assessment Scale and questionnaires about daily life were completed by 153 community-dwelling older adults aged ≥65 years participating in frailty prevention groups in a rural town. The baseline survey was conducted from December 2017 to March 2018 and analysed cross-sectionally. Follow-up surveys were conducted at 1- and 2-years and analysed longitudinally. RESULTS: Univariate and binomial logistic regression analyses at baseline showed no association between MCI and frequency of going out in older adults with physical limitations. However, there was a significant association in older adults without physical limitations. A binomial logistic regression analysis of the frequency of going out at baseline and cognitive function at the 2-year follow-up showed no association between MCI and frequency of going out in older adults with physical limitations, but there was a significant association in those without physical limitations. CONCLUSION: Our results suggest that frequency of going out may not be a useful indicator of MCI in older adults with physical limitations, although low frequency of going out may be an indicator of MCI in older adults without physical limitations.

Detection and recognition thresholds for five basic tastes in patients with mild cognitive impairment and Alzheimer's disease dementia.

BACKGROUND: Patients with Alzheimer's disease dementia (ADD) are thought to exhibit taste disorders; however, this has not been extensively studied. We investigated gustatory functions and factors affecting taste in patients with ADD or mild cognitive impairment (MCI) and in non-demented controls (NDCs) and evaluated associations between cognitive impairment and gustatory functions. METHODS: We recruited 29 patients with ADD, 43 with MCI, and 14 with NDCs. We obtained medical and medication history, measured salivary secretion volumes, and performed cognitive function tests, blood tests, whole-mouth gustatory tests, and dietary and gustatory questionnaires. RESULTS: Patients with ADD showed significantly higher recognition threshold values than NDCs (p < 0.05). Many individuals did not recognize umami at the maximum concentration, and this happened more frequently in patients with ADD or MCI than in NDCs. Evaluation items other than cognitive function tests did not show significant differences among the groups, but many individuals had decreased salivation, low serum zinc levels, and were on multiple medications. We found a significant correlation between recognition threshold and age (r = 0.229, p < 0.05) and cognitive function test score (r = 0.268, p < 0.05). CONCLUSIONS: Patients with ADD showed impairment of gustatory function. Gustatory impairment in patients with MCI could not be confirmed. However, many individuals with MCI did not recognize umami, either. Our results suggest that taste disorders in elderly people with cognitive decline occur independently of factors affecting taste such as salivation, zinc levels, or prescription drugs. TRIAL REGISTRATION: The study was registered in the UMIN Clinical Trials Registry on February 10, 2017, with reference number UMIN000026087.

Evaluation of the effect of aroma oil as a bath salt on cognitive function.

BACKGROUND: Aromatherapy is a non-pharmacological therapy for the improvement of dementia symptoms. This study aimed to assess the effects of aroma oil as a bath salt on cognitive function, olfactory function and sleep quality. METHODS: This was a randomised controlled trial. Overall, 49 patients were able to provide consent, and 35 were finally analysed (Alzheimer's disease: 10, mild cognitive impairment: 25). The patients were randomly assigned to use 0.1%, 0.5% or 1% aroma bath salt. During daily bathing, bath salt was added to the bath water, and the subjects remained in the bathroom for ≥10 min. The intervention period was 24 weeks, and the observation periods were 4 weeks before and after using the aroma bath salt. We performed the Touch Panel-type Dementia Assessment Scale (TDAS), the Odour Stick Identification Test for Japanese (OSIT-J) and the Japanese version of the Pittsburgh Sleep Quality Index (PSQI-J) five times during the before and after observation periods and after the 12-week intervention. RESULTS: There were no significant changes in the TDAS, OSIT-J and PSQI-J scores before and after the intervention in all groups. Moreover, there were no significant differences in the TDAS, OSIT-J and PSQI-J scores between the groups before and after the intervention. In the correlation analysis of changes in the TDAS and other tests during the intervention period, significant associations between TDAS and sleep latency and sleep disturbances, which are sub-items of PSQI-J, were observed in the use of 0.1% aroma bath salt group. CONCLUSIONS: The use of aroma bath salt was not associated with improvement in cognitive function, olfactory function or sleep quality. However, sleep-related aspects were associated with changes in cognitive function before and after use of aroma bath salt, which suggested that there is a link between improvements in sleep and that in cognitive function.

123I-MIBG myocardial scintigraphy for the diagnosis of DLB: a multicentre 3-year follow-up study.

BACKGROUND AND PURPOSE: We previously reported the usefulness of iodine-123 metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy for differentiation of dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) in a cross-sectional multicentre study. The aim of this study was, by using reassessed diagnosis after 3-year follow-up, to evaluate the diagnostic accuracy of 123I-MIBG scintigraphy in differentiation of probable DLB from probable AD. METHODS: We undertook 3-year follow-up of 133 patients with probable or possible DLB or probable AD who had undergone 123I-MIBG myocardial scintigraphy at baseline. An independent consensus panel made final diagnosis at 3-year follow-up. Based on the final diagnosis, we re-evaluated the diagnostic accuracy of 123I-MIBG scintigraphy performed at baseline. RESULTS: Sixty-five patients completed 3-year follow-up assessment. The final diagnoses were probable DLB (n=30), possible DLB (n=3) and probably AD (n=31), and depression (n=1). With a receiver operating characteristic curve analysis of heart-to-mediastinum (H/M) ratios for differentiating probable DLB from probable AD, the sensitivity/specificity were 0.77/0.94 for early images using 2.51 as the threshold of early H/M ratio, and 0.77/0.97 for delayed images using 2.20 as the threshold of delayed H/M ratio. Five of six patients who were diagnosed with possible DLB at baseline and with probable DLB at follow-up had low H/M ratio at baseline. CONCLUSIONS: Our follow-up study confirmed high correlation between abnormal cardiac sympathetic activity evaluated with 123I-MIBG myocardial scintigraphy at baseline and the clinical diagnosis of probable DLB at 3-year follow-up. Its diagnostic usefulness in early stage of DLB was suggested. TRIAL REGISTRATION NUMBER: UMIN00003419.

Comparison of olfactory and gustatory disorders in Alzheimer's disease.

Patients with Alzheimer's disease (AD) develop olfactory and gustatory disorders. However, the order of failure and relevance of the pathophysiology are unclear. We compared olfactory identification and whole mouth gustation in patients with AD to those with mild cognitive impairment (MCI) and to healthy controls (HC) and assessed correlations with pathophysiology. Patients with AD (n = 40), MCI (n = 34), and HC (n = 40) were recruited. We performed the Odor Stick Identification Test for Japanese (OSIT-J), gustatory test by the intraoral dropping method using taste solutions, Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale-cognitive subscale Japanese version (ADAS-J cog), Touch Panel-type Dementia Assessment Scale (TDAS), and measurement of amyloid ß (Aß) 42 and phosphorylated tau (p-tau) 181 levels in cerebrospinal fluid (CSF). Patients with AD and MCI had lower OSIT-J scores than did the HC. The OSIT-J score was correlated with the MMSE, ADAS-J cog, TDAS, and Aß42 results. There were no significant differences in the gustatory test scores among the three groups. The gustatory test score was only correlated with the MMSE, ADAS-J cog, and TDAS results. Olfactory function decreased in AD and MCI patients and was associated with CSF biomarker levels and cognitive disorders. The results suggest that olfactory function is impaired in early stage of AD. Gustatory function was not correlated with CSF biomarkers, which suggests that it may not be impaired in early stage of AD.

[Prevention of dementia].

The dementia prevention consists of three steps, primary prevention of dementia is to prevent from normal and mild cognitive impairment to dementia, secondary prevention is early detection and early treatment of dementia, and tertiary prevention is three stages of progress prevention of dementia. Primary prevention of dementia had been considered impossible until recently, but potential scientific evidence has been shown recently. The fact that 4.62 million people are person with dementia and 400 million people are person with mild cognitive impairment are considered to be urgent problem and we must intend to perform dementia prevention from primary to tertiary prevention thoroughly. We perform dementia screening using touch panel type computer and we recommend person with mild cognitive impairment to join dementia prevention classroom. Therefore, we can prevent progression from mild cognitive impairment to dementia (primary prevention). Early diagnosis and introduction to the specialized medical institution are needed if you find early stage of dementia and treat early (secondary prevention). To prevent progression by the appropriate drug treatment and care for dementia is required (tertiary prevention).

CSF biomarkers for the differential diagnosis of Alzheimer's disease: A large-scale international multicenter study.

INTRODUCTION: The aim of this study was to test the diagnostic value of cerebrospinal fluid (CSF) beta-amyloid (Aß1-42), phosphorylated tau, and total tau (tau) to discriminate Alzheimer's disease (AD) dementia from other forms of dementia. METHODS: A total of 675 CSF samples collected at eight memory clinics were obtained from healthy controls, AD dementia, subjective memory impairment, mild cognitive impairment, vascular dementia, Lewy body dementia (LBD), fronto-temporal dementia (FTD), depression, or other neurological diseases. RESULTS: CSF Aß1-42 showed the best diagnostic accuracy among the CSF biomarkers. At a sensitivity of 85%, the specificity to differentiate AD dementia against other diagnoses ranged from 42% (for LBD, 95% confidence interval or CI = 32-62) to 77% (for FTD, 95% CI = 62-90). DISCUSSION: CSF Aß1-42 discriminates AD dementia from FTD, but shows significant overlap with other non-AD forms of dementia, possibly reflecting the underlying mixed pathologies.

[Dementia].

A female tends to suffer from dementia and dementia is thought as a disease with sex difference clearly. A female has the longer life, so it has been thought that a female prevalence rate is higher than a man seemingly. However, even if sex difference was considered, it was demonstrated clearly in recent years that a female suffer from dementia with high frequencies. Now, it isn't clear yet why such sex difference exists. The strongest hypothesis may be influence by sex hormones, and role of androgen as well as estrogen is pointed out. Now, 15% of more than 65 years old suffer from dementia. Dementia is thought as a common disease". More than 65-year-old elderly people don' t want to suffer from dementia. Although many people have such great interest of dementia, they do not find the early stage symptom of dementia. Forgetfulness is often overlooked and early detection isn't done. There are many diseases which lead to dementia, but Alzheimer-type dementia accounts for the most part of dementia. Alzheimer-type dementia can be treated by medicines, therefore early detection and an early stage check are necessary. I explain how do general physicians notice dementia in their outpatient clinic and diagnose and treat.

[Biological markers for early diagnosis of Alzheimer's disease].

Dementia is a declined state of cognitive functions which impair daily and social life mainly caused by progressive neurodegenerative disease, such as Alzheimer's disease(AD). The present study showed that about 15% of patients in Japan aged over 65 have dementia. The important point regarding the diagnosis of dementia is to detect it as early as possible. It is critical for the diagnosis to measure the indicators in blood and cerebrospinal fluid (CSF). Blood tests are useful to eliminate other factors that lead to cognitive decline derived from physical causes. CSF markers are significant for monitoring the existence and progression of neuropathologies. We need to accumulate extensive knowledge of the features, types, pathologies, development, and progress of dementia in order to assess patients and/or measured values.

[Early detection and prevention of dementia].

Dementia is about 15% aged 65 and over people now, and is regarded as the common disease. Early symptoms, such as forgetfulness, tend to be overlooked. Alzheimer type dementia is now possible to treat with medication. Therefore, early diagnosis and early treatment are required. Prevention of dementia is also expected and dementia checkup attracts attention. Although there was little data with high evidence, I introduced some reports about dementia prevention including our data. Dementia prevention is an important issue and establishment of evidence is desired in the near future.

The relationship between the diagnosis method of neuronal dysfunction (DIMENSION) and brain pathology in the early stages of Alzheimer's disease.

OBJECTIVES: To examine whether the diagnosis method of neuronal dysfunction (DIMENSION), a new electroencephalogram (EEG) analysis method, reflected pathological changes in the early stages of Alzheimer's disease (AD), we conducted a comparative study of cerebrospinal fluid markers and single-photon emission computed tomography. METHODS: Subjects cincluded 32 patients in the early stages of AD with a Mini-Mental State Examination score ≥24 (14 men, 18 women; mean age, 77.3 ± 9.2 years). Cerebrospinal fluid samples were collected from AD patients, and cerebrospinal fluid levels of phosphorylated tau protein (p-tau) 181 and amyloid ß (Aß) 42 were measured with sandwich ELISA. EEG recordings were performed for 5 min with the subjects awake in a resting state with their eyes closed. Then, the mean value of the EEG alpha dipolarity (Dα) and the standard deviation of the EEG alpha dipolarity (Dσ) were calculated with DIMENSION. Single-photon emission computed tomography analyses were also performed for comparison with DIMENSION measures. RESULTS: Patients with parietal hypoperfusion had significantly increasing p-tau181, decreasing Dα, and increasing Dσ. In addition, there was a negative correlation between Dα and p-tau181, p-tau181/Aß42, and a positive correlation between Dσ and p-tau181/Aß42. CONCLUSION: Dα and Dσ were related to cerebral hypoperfusion and p-tau181/Aß42. DIMENSION was able to detect changes in the early-stage Alzheimer's brain, suggesting that it is possibility as a useful examination for early-stage AD with a difficult discrimination in clinical conditions. Moreover, EEG measurement is a quick and easy diagnostic test and is useful for repeated examinations.

Alternative processing of γ-secretase substrates in common forms of mild cognitive impairment and Alzheimer's disease: evidence for γ-secretase dysfunction.

OBJECTIVE: The most common pathogenesis for familial Alzheimer's disease (FAD) involves misprocessing (or alternative processing) of the amyloid precursor protein (APP) by γ-secretase due to mutations of the presenilin 1 (PS1) gene. This misprocessing/alternative processing leads to an increase in the ratio of the level of a minor γ-secretase reaction product (Aß42) to that of the major reaction product (Aß40). Although no PS1 mutations are present, altered Aß42/40 ratios are also observed in sporadic Alzheimer's disease (SAD), and these altered ratios apparently reflect deposition of Aß42 as amyloid. METHODS: Using immunoprecipitation-mass spectrometry with quantitative accuracy, we analyzed in the cerebrospinal fluid (CSF) of various clinical populations the peptide products generated by processing of not only APP but also an unrelated protein, alcadein (Alc). Alc undergoes metabolism by the identical APP α-secretases and γ-secretases, yielding a fragment that we have named p3-Alc(α) because of the parallel genesis of p3-Alc(α) peptides and the p3 fragment of APP. As with Aß, both major and minor p3-Alc(α) s are generated. We studied the alternative processing of p3-Alc(α) in various clinical populations. RESULTS: We previously reported that changes in the Aß42/40 ratio showed covariance in a linear relationship with the levels of p3-Alc(α) [minor/major] ratio in media conditioned by cells expressing FAD-linked PS1 mutants. Here we studied the speciation of p3-Alc(α) in the CSF from 3 groups of human subjects (n = 158): elderly nondemented control subjects; mild cognitive impairment (MCI) subjects with a clinical dementia rating (CDR) of 0.5; SAD subjects with CDR of 1.0; and other neurological disease (OND) control subjects. The CSF minor p3-Alc(α) variant, p3-Alc(α) 38, was elevated (p < 0.05) in MCI subjects or SAD subjects, depending upon whether the data were pooled and analyzed as a single cohort or analyzed individually as 3 separate cohorts. INTERPRETATION: These results suggest that some SAD may involve alternative processing of multiple γ-secretase substrates, raising the possibility that the molecular pathogenesis of SAD might involve γ-secretase dysfunction.

Evaluation of dementia-prevention classes for community-dwelling older adults with mild cognitive impairment.

AIM: The number of elderly people with dementia in Japan is likely to increase as the population ages. In some areas in Tottori Prefecture, dementia-prevention classes have been conducted for several years. In the present study, we evaluated dementia-prevention classes in nine districts of Tottori Prefecture in terms of cognitive function, assessment by the leader and subjective evaluation by participants. METHODS: The study's subjects included 112 community-dwelling elderly residents who were selected after a two-step screening. Data were collected according to the following four factors: (i) evaluation of cognitive function at the beginning and end of classes; (ii) the content of the classes; (iii) observations regarding the state of subjects; and (iv) participants' subjective evaluation obtained via a questionnaire distributed at the final class. RESULTS: In terms of cognitive function among all subjects, scores significantly improved after the dementia-prevention classes. However, there were no significant cognitive improvements in the districts where programmes were biased towards a single category (e.g. systemic exercise, creative activities). Based on class leaders' assessments, subjects showed improved appearance and facial expression in later classes. Participants became more involved in the programmes, and their interests in others increased. In terms of their daily lives, subjects became more involved with others and more active after participating in the classes. CONCLUSIONS: Dementia-prevention classes improved not only cognitive function but also other aspects of daily life, as well. We thought it was important to evaluate both objective and subjective factors related to the classes.

Dementia Prevention and Aromatherapy in Japan.

Until recently, it was thought that dementia prevention was not possible. However, a recent paper reported that 40% of the risk factors for developing dementia are modifiable. Large-scale clinical studies on dementia prevention and various initiatives to reduce the risk of developing dementia have been made worldwide. In addition to the introduction of a global initiative in dementia prevention, I also introduce the results of our research on the development of the Tottori method dementia prevention program and aromatherapy to approach olfactory impairment in Alzheimer's disease.

Verification of the association between cognitive decline and olfactory dysfunction using a DEmentia screening kit in subjects with Alzheimer's dementia, mild cognitive impairment, and normal cognitive function (DESK study): A multicenter, open-label, interventional study.

Background and purpose: Olfactory dysfunction may be an early symptom of degenerative neurological disorders such as mild cognitive impairment (MCI), which may progress to cognitive decline and Alzheimer's disease (AD). We investigated the relationship between cognitive decline and olfactory dysfunction in healthy controls and patients with MCI or AD using the DEmentia Screening Kit (DESK), an olfactory identification assessment tool designed for Japanese populations. Methods: In this multicenter, open-label, interventional study conducted from 16 September 2020 to 30 April 2021, participants underwent olfactory tests using the DESK tool. This included 10 odorants at two concentrations (weak/strong) including toothpaste, butter, and India ink. Results: Among 223 participants, 100, 61, and 62 were healthy controls, MCI patients, and AD patients (mean ages, 57.4, 72.8, and 76.3 years; total DESK olfaction scores, 18.4, 14.7, and 7.4), respectively. Significant differences in total olfaction scores were observed between groups (healthy controls vs MCI, healthy controls vs AD, and MCI vs AD). Significant between-group total score differences were shown for olfaction scores with both the 10 strong and 10 weak odorant varieties. Conclusion: The DESK tool may discriminate between healthy individuals and those with MCI or AD, facilitating early screening for cognitive decline among Japanese patients, although the effect of age on DESK olfaction scores has not been fully explored.

Touch Panel-type Dementia Assessment Scale: a new computer-based rating scale for Alzheimer's disease.

BACKGROUND: The Alzheimer's Disease Assessment Scale (ADAS) was designed as a rating scale for the severity of dysfunction in the cognitive and non-cognitive behaviours that are characteristic of persons with Alzheimer's disease. Its subscale, the ADAS-cog, is a cognitive testing instrument most widely used to measure the impact of the disease. However, the ADAS-cog takes more than 45 min to administer and requires a qualified clinical psychologist as the rater. A more comprehensive rating battery is therefore required. In the present study, we developed a computerized test battery named the Touch Panel-type Dementia Assessment Scale (TDAS), which was intended to substitute for the ADAS-Cog, and was specifically designed to rate cognitive dysfunction quickly and without the need of a specialist rater. METHODS: The hardware for the TDAS comprises a 14-inch touch panel display and computer devices built into one case. The TDAS runs on Windows OS and was bundled with a custom program made with reference to the ADAS-cog. Participants in the present study were 34 patients with Alzheimer's disease. Each participant was administered the ADAS-cog and the TDAS. The test scores for each patient were compared to determine whether the severity of cognitive dysfunction of the patients could be rated equally as well by both tests. RESULTS: Pearson's correlation coefficient showed a significant correlation between the total scores (r= 0.69, P < 0.01) on the two scales for each patient. The Kendall coefficients of concordance obtained for the three corresponding pairs of tasks (word recognition, orientation, and naming object and fingers) showed the three TDAS tasks can rate symptoms of cognitive decline equally as well as the corresponding items on the ADAS-cog. CONCLUSIONS: The TDAS appears to be a sensitive and comprehensive assessment battery for rating the symptoms of Alzheimer's disease, and can be substituted for the ADAS-cog.

Specific feature of olfactory dysfunction with Alzheimer's disease inspected by the Odor Stick Identification Test.

AIM: Alzheimer's disease (AD) is one of the most significant diseases associated with ageing. As the disease progresses, symptoms including olfactory dysfunction often appear along with cognitive dysfunction. We examined olfactory and other indexes to investigate correlations between them and the validity of an olfactory test for screening for AD. METHODS: To assess whether odorant identification will be a useful diagnostic tool, we investigated the olfactory ability of Alzheimer's disease patients (ADs) using the Odor Stick Identification Test for the Japanese. As a control, we compared ADs to aged people without AD or dementia. To investigate the relationship between olfactory loss and severity of AD, we used the Mini-Mental State Examination, Alzheimer's Disease Assessment Scale, biomarkers in spinal fluid and single-photon emission computed tomography as brain imaging. RESULTS: In comparing the controls and ADs, we believe that there are significant differences, with ADs having particularly low activity with regard to olfactory function and some odorants. We showed that there was a definite correlation between cognitive and olfactory function. To confirm this, we sorted subjects by markers of severity scores for comparison. In all areas, the AD group had more serious olfactory dysfunction, including in the early stages of AD. CONCLUSION: This study suggests that olfactory tests such as the Odor Stick Identification Test for the Japanese can be useful for assessing severity of AD, including cognitive dysfunction. Further investigations will enable us to establish an olfactory assessment method for the screening or diagnosis of AD.

Examination of the cognitive function of Japanese community-dwelling older adults in a class for preventing cognitive decline during the COVID-19 pandemic.

We examined the changes in cognitive function due to restrictions in daily life during the coronavirus disease 2019 (COVID-19) pandemic in community-dwelling older adults with mild cognitive decline. This was a retrospective, case-control study. The participants include 88 older adults with mild cognitive decline (mean age = 81.0 [standard deviation = 6.5] years) who participated in a class designed to help prevent cognitive decline. This class was suspended from early-March to end of May 2020 to prevent the spread of COVID-19, and resumed in June 2020. We collected demographic and cognitive function test data (Touch Panel-type Dementia Assessment Scale [TDAS]) before and after class suspension and questionnaire data on their lifestyle and thoughts during the suspension. Change in TDAS scores from before and after the suspension was used to divide the participants into decline (2 or more points worsening) and non-decline (all other participants) groups, with 16 (18.2%) and 72 (81.8%) participants in each group, respectively. A logistic regression model showed that the odds ratio (OR) for cognitive decline was lower in participants whose responses were "engaged in hobbies" (OR = 0.07, p = 0.015), "worked on a worksheet about cognitive training provided by the town hall" (OR = 0.19, p = 0.026), and "had conversations over the phone" (OR = 0.28, p = 0.0495). There was a significant improvement in TDAS scores after class was resumed (p < 0.01). A proactive approach to intellectual activities and social ties may be important for the prevention of cognitive decline during periods of restrictions due to COVID-19. We found that cognitive function test scores before class suspension significantly improved after resuming classes. We speculate that continued participation in this class led to positive behavioral changes in daily life during periods of restriction due to COVID-19.