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Purpose Evidence has suggested that adherence to a Japanese diet may be beneficial for health. However, its association with incident dementia remains unclear. The aim was to explore this association in older Japanese community-dwellers, taking apoprotein E genotype into consideration. Methods A 20-year follow-up cohort study involving 1504 dementia-free older Japanese community-dwellers (aged 65–82 years) living in Aichi Prefecture, Japan, was conducted. Based on a previous study, a 9-component-weighted Japanese Diet Index (wJDI9) score (range − 1 to 12) was calculated using 3-day dietary record data and used as an indicator of adherence to a Japanese diet. Incident dementia was confirmed by the Long-term Care Insurance System certificate, and dementia events occurring within the first 5 years of follow-up were excluded. A multivariate-adjusted Cox proportional hazards model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident dementia, and Laplace regression was used to estimate percentile differences (PDs) and 95% CIs (expressed in months) in age at incident dementia (i.e., dementia-free duration differences), according to tertiles (T1–T3) of wJDI9 scores. Results The median (IQR) follow-up duration was 11.4 (7.8–15.1) years. During the follow-up period, 225 (15.0%) cases of incident dementia were identified. Because the smallest prevalence of incident dementia was 10.7% for the T3 group of wJDI9 scores, to avoid inaccurately estimating the dementia-free duration of participants in the T3 group, the 11th PDs in age at incident dementia between the T1 and T3 groups of wJDI9 scores were estimated. A higher wJDI9 score was associated with a lower risk of incident dementia and a longer dementia-free duration difference. The multivariate-adjusted HR (95% CI) and 11th PDs (95% CI) in age at incident dementia for participants in the T1 vs. T3 group were 1.00 (reference) vs. 0.58 (0.40, 0.86), and 0 (reference) vs. 36.7 (9.9, 63.4) months, respectively. Each 1-point increase of the wJDI9 score was associated with a 5% lower risk of incident dementia (P value = 0.033) and 3.9 (0.3, 7.6) additional months of dementia-free duration (P value = 0.035). No differences were seen in sex or smoking status (current smoker vs. non-current smoker) at baseline. Conclusion These findings suggest that adherence to a Japanese diet defined by wJDI9 is associated with a lower risk of incident dementia in older Japanese community-dwellers, suggesting the benefit of the Japanese diet for dementia prevention.

Carriers of the apolipoprotein E ε4 allele (APOEɛ4) have an increased risk of developing dementia (e.g., Alzheimer's disease). However, it is less clear whether the APOEɛ4 might also be involved in cognitive aging among the non-clinical population of older adults. While some studies have suggested that the APOEɛ4 is related to accelerated cognitive decline in the normal aging process, others have failed to provide compelling evidence of such an impact. Notably, these discrepancies may depend on methodological shortcomings, including short time spans, few assessments, and small sample sizes. The present study overcomes the above limitations and aims to clarify the impact of the APOEɛ4 genotype on long-term longitudinal changes in cognitive functions in middle-aged and older adults in Japan.The data were retrieved from the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) survey (N = 1832; 40 to 79 years of age at baseline). The participants were tested over nine waves covering a period of approximately 20 years. Latent Growth Curve (LGC) modeling was employed to test the impact of the interaction between APOEɛ4 status and age on several cognitive functions. Four tests of the WAIS-R were administered: Information, Similarities, Picture completion, and Digit Symbol Substitution Test (DSST). The results showed that the APOEɛ4 carriers experienced a more pronounced decline in the DSST (p = 0.001) and Similarities (p = 0.022) tests. A similar tendency was found in the Information test (p = 0.034). By contrast, no effect was found in the Picture completion test (p = 0.563).APOEɛ4 carriers seem to exhibit a steeper cognitive decline, which becomes apparent in old age. This effect is more robust in fluid cognitive skills (DSST) than crystallized cognitive skills (Information and Similarities). Overall, the APOEɛ4 genotype may be a significant risk factor in normal (i.e., non-clinical) cognitive aging.

Background/Objectives Dietary habits are known to affect health, including the rate of brain ageing and susceptibility to diseases. This study examines the longitudinal relationship between dietary diversity and hippocampal volume, which is a key structure of memory processing and is known to be impaired in dementia. Subjects/Methods Subjects were aged 40–89 years (n = 1683, men: 50.6%) and participated in a 2-year follow-up study of the National Institute for Longevity Sciences-Longitudinal Study of Aging. Dietary intake was calculated from 3-day dietary records, and dietary diversity was determined using the Quantitative Index for Dietary Diversity at baseline. Longitudinal changes in hippocampal and total grey matter volumes were estimated by T1-weighted brain magnetic resonance imaging and FreeSurfer software. Estimated mean brain volume change in relation to dietary diversity score quintiles was assessed by the general linear model, adjusted for age, sex, education, smoking status, alcohol intake, physical activity, and comorbidities. Results The mean (± standard deviation) % decreases in hippocampal and total grey matter volume during the 2-year follow-up were 1.00% (±2.27%) and 0.78% (±1.83%), respectively. Multivariate-adjusted decreases in total grey matter volume were associated with dietary diversity score (p = 0.065, p for trend = 0.017), and the % decrease in hippocampal volume was more strongly associated with the dietary diversity score: the estimated mean (± standard error) values were 1.31% (±0.12%), 1.07% (±0.12%), 0.98% (±0.12%), 0.81% (±0.12%), and 0.85% (±0.12%), according to dietary diversity quintiles in ascending order (p = 0.030, p for trend = 0.003). Conclusions Among community dwellers, increased dietary diversity may be a new nutritional strategy to prevent hippocampal atrophy.

Prior evidence suggests that subjective well-being (SWB) remains relatively stable across adulthood. However, longitudinal evidence is sparse except in Western societies such as North America and Western Europe. We examined age-related changes in SWB (life satisfaction, positive affect, and negative affect) among middle-aged and older Japanese. We applied multilevel growth models to 14-year seven-wave longitudinal data of a dynamic cohort study. A total of 3,890 participants aged 40–81 at first assessment were included in the analysis. The longitudinal results demonstrated differential trajectories of SWB. Life satisfaction exhibited an accelerated increase in middle age but decreased and leveled off in old age. Positive affect increased in midlife and declined in late life. Negative affect remained stable in middle age but increased in old age. Demographics, health, and methodological correlates did not fully account for age-related changes in SWB. Of note, increases in negative affect in old age remained evident even after controlling for the correlates. In conclusion, life satisfaction was stable across adulthood, which was not the case with positive and negative affect. We discussed the possible mechanisms in these observed trajectories of SWB, in particular, negative affect in late life.

Background The gap between the average life expectancy and healthy life expectancy remains wide. Understanding the natural history of frailty development is necessary to prevent and treat frailty to overcome this gap. This study elucidated the trajectories of 5 frailty assessment components using group-based multitrajectory modeling. Methods Overall, 845 community-dwelling older adults (aged 65–91 years; 433 males and 412 females) who underwent longitudinal frailty assessments at least 3 times were included in the analysis. The mean follow-up period (±SD, range) was 7.1 (±2.3, 3.8–11.3) years. In each wave, the physical frailty was assessed for the following 5 partially modified components of the Cardiovascular Health Study criteria: shrinking, weakness, exhaustion, slowness, and low activity. Using group-based multitrajectory modeling, we identified subgroups that followed distinctive trajectories regarding the 5 frailty components. Results Five frailty trajectory groups were identified: weakness-focused frail progression group (Group 1 [G1]; 10.9%), robust maintenance group (Group 2 [G2]; 43.7%), exhaustion-focused prefrail group (Group 3 [G3]; 24.3%), frail progression group (Group 4 [G4]; 6.7%), and low activity–focused prefrail group (Group 5 [G5]; 14.4%). The Cox proportional hazards model analysis showed that G1, G4, and G5 had significantly higher mortality risks after adjusting for sex and age (G2 was the reference group). Conclusion Based on the natural history of frailty, the 5 distinctive trajectory groups showed that some individuals remained robust, while others remained predominantly prefrail or progressed primarily owing to physical mobility decline. Therefore, identifying individuals belonging to these progressive frailty groups and providing interventions according to the characteristics of each group may be beneficial.

Background To investigate the association between green tea consumption and the annual rate of change of gray matter (GM), white matter (WM), and hippocampal volumes in middle-aged and older Japanese community-dwellers. Methods A prospective cohort study with two years of follow-up was conducted with 1693 participants (aged 40–89 years). Green tea consumption (mL/day) data were collected with a 3-day dietary record. Volumes of GM, WM, and the hippocampus were estimated by T1-weighted brain magnetic resonance imaging and FreeSurfer software. The GM ratio, WM ratio, and hippocampal ratio (HR) were calculated as the percentages of total intracranial volume, respectively. Results The mean (SD) annual rate of change of hippocampal volume [(HR at baseline - HR at follow-up)/HR at baseline/follow-up years×100%] was 0.499 (1.128) (%). In the multivariable-adjusted general linear model, green tea consumption at baseline was negatively associated only with the annual rate of change of hippocampal volume (%) [β (95% CI) for each 1 mL/day increase in green tea consumption = -20.2E-5 (-35.0E-5 to -5.3E-5); P-value = 0.008]. No associations were observed for the annual rate of change of GM or WM volumes. The results remained significant when the analysis was limited to those with stable green tea consumption and were especially evident among individuals aged 65 years and older and among women. Conclusions In this study, each additional 100 mL/day of green tea intake was related to a reduction of approximately 5% in annual hippocampal atrophy. This association was especially evident among older individuals and among women. Key messages A negative association between green tea consumption and brain atrophy has been suggested; however, this relationship has not yet been investigated in humans. In this study, for the first time, a negative association between green tea consumption and annual hippocampal atrophy was observed in community-dwelling middle-aged and older individuals.

The amount of breakfast protein intake is important for maintaining muscle strength. However, the effect of breakfast protein quality (ie, bioavailability) remains unclear. We investigated the association between breakfast protein quality and the incidence of muscle weakness.Longitudinal study.Healthy older adults age 60-83 years without stroke, arthritis, Parkinson disease, or muscle weakness at baseline (maximum follow-up period and participations were 9.2 years and 5 times, respectively).Weakness was defined by the Asian Working Group for Sarcopenia 2019 criteria, using grip strength. Breakfast protein quality was evaluated using the protein digestibility-corrected amino acid score (PDCAAS), where higher scores represent higher quality, calculated from 3-day dietary records. Participants were classified according to sex-stratified tertiles of breakfast PDCAAS (ie, low to high groups). The association between PDCAAS and incident weakness was analyzed using the generalized estimating equation, after adjusting for sex, age, follow-up time, grip strength, body mass index, physical activity, cognition, education, smoking, economics, medical history, lunch and dinner PDCAASs, and energy and protein intake during 3 regular meals at baseline.Overall, 14.4% of the initial sample was excluded owing to a diagnosis of weakness-related diseases, and 58.3% (n = 701) had at least 1 follow-up measurement for inclusion in the analysis. The mean ± SD follow-up period was 6.9 ± 2.1 years; the cumulative number of participants was 3019, and 282 developed weakness. Using the low PDCAAS group as the reference, the adjusted odds ratios (95% CIs) for incident weakness in the middle and high PDCAAS groups were 0.71 (0.43-1.18) and 0.50 (0.29-0.86), respectively.Higher breakfast protein quality was associated with a reduction in incident weakness in older adults, independent of protein intake. These findings may highlight the role of protein quality for muscle health in older adults.

This study explores the clusters of work–family balance (WFB) among Japanese middle-aged and older adults and clarifies the characteristics of the derived clusters. Data on working adults (N = 1,351; age range = 40–85 years) were drawn from a pool of participants in the National Institute for Longevity Sciences—Longitudinal Study of Aging. The WFB scale consists of subscales assessing work–family conflict (WFC) and work–family facilitation (WFF). First, a cluster analysis was performed using the WFB scale, and four clusters were extracted. Second, we examined associations between the four clusters and related variables such as demographic characteristics, work, family, and lifestyle factors, social support, and mental health. Our findings showed that the clusters included high-WFC/high-WFF, high-WFC/low-WFF, low-WFC/high-WFF, and low-WFC/low-WFF. Differences were found in related variables among the clusters. Specifically, those in the Low-WFC/High-WFF cluster had a good lifestyle, received the highest levels of social support, and had the fewest mental health issues. Our findings have implications for maintaining sufficient WFB and promoting positive mental health among workers.

Background There is a growing interest in the significance of adopting a variety of lifestyle habits for maintaining cognitive function among older adults. A lifestyle that is easy to modify, simple, and less burdensome for older people is ideal. We investigated the longitudinal association between global cognitive decline and cognitive leisure activities (CLAs) combined with long-chain polyunsaturated fatty acids (LCPUFAs) intake. Methods The National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) enrolled community-dwelling middle-aged and older men and women who were randomly selected from Obu-City and Higashiura Town, Aichi, Japan. Baseline data (2006–2008), including CLAs and dietary intake, were obtained from 517 participants (aged 60–84 years) with normal cognition. Global cognitive decline, defined as the Mini-Mental State Examination (MMSE) score ≤ 27, was assessed at baseline and four years later. Interaction between CLAs and LCPUFAs on cognitive decline was investigated using a multiple logistic analysis with adjustment for confounders. CLA engagement and LCPUFA intake were divided into high and low groups according to the frequency at which each participant engaged in the activity and the median intake level according to sex, respectively. Results A significant interaction was detected for the combination of CLA engagement and LCPUFA intake. Logistic regression coefficients revealed significant interactions when participants engaged in more than five CLA varieties. One of the CLAs, art appreciation, produced a significant main effect against cognitive decline and a significant interaction in combination with LCPUFA intake. The major LCPUFAs—docosahexaenoic acid and arachidonic acid—also exhibited a significant interaction. The combination of high LCPUFA intake and high art appreciation frequency yielded a lower adjusted odds ratio for cognitive decline than the combination of low LCPUFA and low art appreciation [0.25 (95 % confidence intervals, 0.11–0.56)]. Conclusions Preserving cognitive function might be associated with a combination of varied and high-frequency engagement in CLAs combined with high LCPUFA intake.

Objective:To examine the association between green tea and coffee intake and cognitive decline in older adults.Design:A prospective cohort study. The average intake of green tea and coffee in the previous year was assessed through a dietitian interview using a dietary questionnaire. A Mini-Mental State Examination (MMSE) was conducted up to six times biennially. Cognitive decline was screened using the MMSE; its incidence was defined as the first time a score of Setting:The National Institute for Longevity Sciences, Longitudinal Study of Aging (NILS-LSA) in Japan.Participants:Men (n 620) and women (n 685), aged 60–85 years, from the NILS-LSA.Results:During a mean of 5·3 (sd 2·9) years of follow-up, 432 incident cases of cognitive decline were observed. Compared with participants who consumed green tea Ptrend < 0·05). No significant association was found between coffee intake and cognitive decline.Conclusions:The intake of green tea, but not coffee, was shown to reduce the risk of cognitive decline in older adults.

The brain controls human behavior, and the gray matter is the main resource of neuronal cells. We examined the longitudinal relationship between six basic lifestyle habits (diet, exercise, sleep, alcohol consumption, smoking, and social activity including employment) and total gray matter volume in community-dwelling adults in Japan. This two-year follow-up study with data derived from the National Institute for Longevity Sciences, Longitudinal Study of Aging, Aichi, Japan, included adults aged 40-87 years (n = 1665, men: 51%). Lifestyle habits were assessed at baseline (2008-2010) using self-reported questionnaires and three-day dietary records. Total gray matter volume at baseline and after two years was estimated using T1-weighted brain magnetic resonance imaging and FreeSurfer software. The association between each lifestyle factor, the total number of healthy lifestyle habits, and gray matter volume change was determined via a multiple linear regression analysis adjusting for baseline age, total gray matter volume, and other confounders. The mean ± standard deviation decrease in total gray matter volume during the two-year follow-up period was 0.94 ± 1.86% in men and 0.61 ± 2.27% in women. In the multiple regression analysis, volume loss in total gray matter positively correlated with male smoking, while it was negatively correlated with male social activity and employment, female dietary diversity, and the total number of healthy lifestyle habits (standardized beta coefficient; -0.061 in men [p = 0.07], -0.113 in women [p 0.05]). Therefore, engaging in social activities, non-smoking, a diverse diet, or adopting one healthy lifestyle habit may help prevent gray matter volume loss.

Positive affect contributes to health and longevity. While most research has been conducted in individualistic societies where the experience and expression of positive emotions are highly valued, evidence remains scarce in collectivistic societies that de-emphasize the importance thereof. Employing 19-year longitudinal data of Japanese adults (age range 40‒79; N = 2,033), we examined whether positive affect predicted mortality and morbidity. Health outcomes were all-cause and cause-specific mortality as well as the onset of morbidity (heart disease, stroke, hypertension, diabetes, and cancer). After adjusting for relevant covariates, the Cox proportional hazards models revealed that positive affect predicted none of the outcomes. Our results did not replicate the health−benefits of positive affect. We discussed potential reasons for the null results.

Background To investigate the association between green tea consumption and the annual rate of change of gray matter (GM), white matter (WM), and hippocampal volumes in community-dwelling middle-aged and older Japanese individuals. Methods A prospective cohort study with two years of follow-up was conducted as part of the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) project. A total of 1693 participants (862 men and 831 women, aged 40–89 years) were included. Green tea consumption (mL/day) data were collected with a 3-day dietary record. Volumes of GM, WM, and the hippocampus were estimated by T1-weighted brain magnetic resonance imaging and FreeSurfer software. The GM ratio, WM ratio, and hippocampal ratio (HR) were calculated as the percentages of total intracranial volume, respectively. Results The mean (SD) annual rate of change of hippocampal volume [(HR at baseline - HR at follow-up)/HR at baseline/follow-up years×100%] was 0.499 (1.128) (%). In the multivariable-adjusted general linear model, green tea consumption was negatively associated only with the annual rate of change of hippocampal volume (%) [β (95% CI) for each 1 mL/day increase in green tea consumption = -20.2E-5 (-35.0E-5 to -5.3E-5); P-value = 0.008]. No associations were observed for the annual rate of change of GM or WM volumes. The results remained significant when the analysis was limited to those with stable green tea consumption and were especially evident among individuals aged 65 years and older and among women. Conclusions In this study, higher green tea consumption was associated with less annual hippocampal atrophy, and each additional 100 mL/day of green tea intake was related to a reduction of approximately 5% in annual hippocampal atrophy. This association was especially evident among older individuals and among women. Further study in different settings is needed to confirm this association.

We examined associations between dietary diversity and all-cause and cause-specific mortality in 386 men and 413 women (age range, 60&ndash, 79 years at baseline) who took part in the National Institute for Longevity Sciences-Longitudinal Study of Aging study from 1997 to 2000. Dietary intake was assessed using three-day dietary records and photographs. The Quantitative Index for Dietary Diversity was used to determine the dietary diversity among thirteen food groups. Dietary diversity score and each food intake were examined by sex-stratified tertiles, and hazard ratios (HR) were calculated to compare the risk for all-cause and cause-specific deaths across tertiles, after controlling for age, sex, body mass index, alcohol intake, smoking status, education, physical activity, and disease history. During a mean follow-up of 15.7 years, 289 subjects (36.2%) died. Compared to the subjects in the lowest tertile, the multivariate-adjusted HR for all-cause and cancer mortality was 0.69 (95% confidence interval (CI): 0.51&ndash, 0.94) and 0.57 (95% CI: 0.33&ndash, 0.98), respectively (trend p &lt, 0.05), in subjects in the highest tertile of dietary diversity. There were no significant associations between dietary diversity score and death from cardiovascular or cerebrovascular disease. Eating a variety of foods might contribute to longevity in older Japanese community dwellers.

Nutrition plays an important role in the development of frailty, and the present study examined the association between energy, macronutrient, and food intake and the development of physical frailty. Prospective cohort study. The National Institute for Longevity Sciences — Longitudinal Study of Aging (NILS-LSA), a community-based study. Participants included 166 men and 117 women aged 65–86 years without frailty components at baseline who participated in both the sixth (2008–2010) and seventh (2010–2012) waves of the NILS-LSA. Physical frailty was assessed using the modified criteria established by the Cardiovascular Health Study (2001). All participants were classified as “robust (number of frailty components: 0),” “prefrail (1–2),” or “frail (3–5).” Energy, macronutrient, and food intake was calculated based on 3-day dietary records during the sixth wave. Associations between dietary intake per day and the development of frailty 2 years later (from robust at the sixth wave to prefrail/frail at the seventh wave) were examined using multiple logistic regression analysis after adjusting for sex, baseline age, and other covariables. Among the participants included, 36% were classified as prefrail/frail 2 years later. Higher energy [1 standard deviation (SD), odds ratio (95% confidence interval): 362 kcal, 0.68 (0.49–0.94)], protein [16 g, 0.72 (0.53–0.97)], and fat [15 g, 0.69 (0.52–0.92)] intake was negatively associated with frailty development. Higher meat [38 g, 0.68 (0.51–0.92)] and dairy [114 g, 0.73 (0.55–0.96)] intake was negatively associated with frailty development. Higher energy intake was negatively associated with the development of weakness (low grip strength) and low activity, while higher protein intake was negatively associated with the development of low activity. Increased consumption of meat and dairy products may provide sufficient protein and fat necessary for achieving higher energy intake, thereby effectively preventing physical frailty among older Japanese individuals.

Objectives The pathology of sudden sensorineural hearing loss, which is known as sudden deafness (SD), remains unknown. The purpose of this study was to investigate the association between mitochondrial uncoupling protein 2 (UCP2) polymorphism and SD risk. Materials and methods We compared 83 patients suffering from SD and 2048 controls who participated in the Longitudinal Study of Aging at the National Institute for Longevity Sciences. Multiple logistic regression was used to calculate the odds ratios (ORs) for SD with a polymorphism of the UCP2 (rs660339) gene. Results Under the additive model of inheritance, UCP2 polymorphisms showed significant association with a SD risk. The OR was 1.468 (95% confidence interval, 1.056-2.040) with an adjustment for any past history, such as diabetes, dyslipidemia, or hypertension, and for age and sex. Conclusion Our results imply that the UCP2 (rs660339) polymorphism has a significant association with the risk of developing SD.

Objective This study aimed to assess the relationship between weight gain from early adulthood and visceral fat accumulation. Methods The participants were 549 men aged 42 to 64 years who were randomly selected from the local resident registry for the National Institute for Longevity Sciences' neighbourhood. They were asked to recall their weight at 18 years of age, and then, post-18 weight-change values were calculated for each participant (their current weight minus their weight at 18). The participants were divided according to their median body mass index (BMI) at 18 years of age (initial BMI) (

Data were derived from the National Institute for Longevity Sciences-Longitudinal Study of Aging. Subjects comprised 403 men and 373 women aged 60-81 years at baseline who participated in the follow-up study at least once. Bean, soy product and soy isoflavone intake was assessed using a 3-day dietary record at baseline. Cognitive function was assessed by the Mini-Mental State Examination (MMSE). MMSE scores of ≤23 were used to define cognitive impairment. The relationship between bean, soy product and soy isoflavone intake and cognitive impairment was assessed using a generalized estimating equation. Multivariate-adjusted odds ratios (95% confidence intervals) for cognitive impairment with a 1 s.d. increase in total bean, total soybean and total soy isoflavone intakes were 0.48 (0.28-0.81; p = 0.006), 0.51 (0.32-0.83; p = 0.007), and 0.55 (0.32-0.93; p = 0.026), respectively, in women. Total soybean and soy isoflavone intake might decrease the risk of cognitive impairment in elderly Japanese women.

Positive and negative associations with risk of cognitive decline have been reported for glycated hemoglobin (HbA1c) level and green tea (GT) intake, respectively. This study aimed to assess whether the reduction in the risk of cognitive decline with GT intake depended on HbA1c level. The participants were aged ≥60 years at baseline in the cohort study, wherein examinations were conducted biennially from 2000 to 2012. Subjects (n=1,304) who had no cognitive decline during the first survey and who had participated in the follow-up survey at least once were included. The follow-up end point was the first screening time point for cognitive decline (Mini-Mental State Examination score

The relationship between openness (a psychological trait of curiosity) and a cognitive change was examined in middle-aged and older adults. Participants were 2214 men and women (baseline age range: 40 to 81 years). They were tested up to seven times over approximately 13 years. Openness at the baseline was assessed by the NEO Five-Factor Inventory. Cognitive abilities were assessed at each examination using the Wechsler adult intelligence scale-revised short form, which includes information, similarities, picture completion, and digit symbol subscales. General linear mixed models comprised fixed effects of openness, age at the baseline, follow-up time, their interactions, and the covariates. The results indicated that the main effects of openness were significant for all scores. Moreover, the interaction term openness &times, age &times, time was significant for the information and similarities test scores, indicating that changes in the information and similarities scores differed depending on the level of openness and baseline age. The estimated trajectory indicated that the differences in slopes between participants with high and low openness were significant after 60 years of age for the information, and after 65 years of age for the similarities scores. It is concluded that openness has a protective effect on the decline in general knowledge and logical abstract thinking in old age.

Inhibition of angiotensin-converting enzyme (ACE) is a strategy used worldwide for managing hypertension. In addition to converting angiotensin I to angiotensin II, ACE also converts neurotoxic β-amyloid protein 42 (Aβ42) to Aβ40. Because of its neurotoxicity, Aβ42 is believed to play a causative role in the development of Alzheimer's disease (AD), whereas Aβ40 has neuroprotective effects against Aβ42 aggregation and also against metal-induced oxidative damage. Whether ACE inhibition enhances Aβ42 aggregation or impairs human cognitive ability are very important issues for preventing AD onset and for optimal hypertension management. In an 8-year longitudinal study, we found here that the mean intelligence quotient of male, but not female, hypertensive patients taking ACE inhibitors declined more rapidly than that of others taking no ACE inhibitors. Moreover, the sera of all AD patients exhibited a decrease in Aβ42-to-Aβ40–converting activity compared with sera from age-matched healthy individuals. Using human amyloid precursor protein transgenic mice, we found that a clinical dose of an ACE inhibitor was sufficient to increase brain amyloid deposition. We also generated human amyloid precursor protein/ACE(+/−) mice and found that a decrease in ACE levels promoted Aβ42 deposition and increased the number of apoptotic neurons. These results suggest that inhibition of ACE activity is a risk factor for impaired human cognition and for triggering AD onset.

Objectives To examine the longitudinal associations between the big five personality and changes in global cognitive function among community-dwelling elderly people involved in the National Institute for Longevity Sciences - Longitudinal Study of Aging. Methods The participants were 594 individuals (age range 60–81 years) and followed for 10 years and tested six times. Personality was assessed by the Japanese version of NEO five factor inventory at baseline. Cognitive function was assessed by the Japanese version of Mini Mental State Examination (MMSE) at all visits. For participants with a baseline MMSE score ≥ 28, logistic generalized estimating equation models estimated the odds ratio (OR) and 95% confidence interval (CI) for MMSE score ≤ 27 at each follow-up visit, according to a 1-SD increase of the baseline personality score. Post hoc analyses were performed for mild cognitive deficits, baseline MMSE score ≥ 24 and ≤ 27, to estimate the OR and CI for MMSE score ≤ 23. Results The adjusted OR for MMSE score ≤ 27 was 0.78 (95% CI, 0.69–0.88), with a 1-SD increase in Openness to Experience score. In post hoc analyses, the adjusted OR for MMSE score ≤ 23 was 0.50 (95% CI, 0.35–0.72) with a 1-SD increase in Conscientiousness score. Relationships between other personality traits and the decline in MMSE score were not significant. Conclusions Higher Openness to Experience was associated with a reduction in risk for cognitive decline in community-dwelling older adults. Higher Conscientiousness might also predict lower risk for severe cognitive decline, especially for individuals with mild cognitive deficits.

Background: Whether smokers and former smokers have worse lipid profiles or glucose levels than non-smokers remains unclear. Methods: The subjects were 1152 Japanese males aged 42 to 81 years. The subjects were divided according to their smoking habits (nonsmokers, former smokers, and current smokers) and their visceral fat area (VFA) (

The purpose of this study was to estimate sex differences in age-related grip strength decline and describe the course of decline in grip strength from age 40 to 89 years by a longitudinal epidemiological study. Participants were randomly selected community-living men (n = 648) and women (n = 598) aged 40 to 79 years at baseline. Grip strength was measured with standard techniques every other year over a 10-year period. The preservation rate of grip strength was calculated as the 10-year follow-up value divided by the baseline value. The relationship between the preservation rates of grip strength and age group (by decade) at baseline by sex was analyzed using Two-Way Analysis of Variance and the Tukey-Kramer method. The trajectories of grip strength over 10 years were plotted for both men and women. The mean grip strength preservation rates of participants in their 40s, 50s, 60s and 70s over 10 years was 0.90, 0.88, 0.84 and 0.79 in men, and 0.89, 0.89, 0.89 and 0.88 in women, respectively. There were significant differences in sex and age group at baseline in the preservation rate of grip strength. Among men, the preservation rate of grip strength for the 70s group was significantly lower than that of younger groups (p < 0.05); however, no significant difference was observed among age groups in women. The trajectories of grip strength decline year by year were steep in men, but even in women. Age-related decline in grip strength markedly increased in older men, but remained constant throughout middle and late adulthood in women.