National Institute For Longevity Sciences, Longitudinal Study Of Aging Research Articles

Association of taurine intake with changes in physical fitness among community-dwelling middle-aged and older Japanese adults: an 8-year longitudinal study.

Taurine has diverse valuable biological functions, including antioxidant activity and regulation of osmotic pressure. Maintaining physical fitness from middle age is important for healthy life expectancy. Although taurine administration improves muscle endurance and strength, its role in maintenance remains unclear. We aimed to clarify the longitudinal taurine intake association with fitness changes. Participants comprised men and women aged ≥40 years who participated in the third (2002-2004; Baseline) and seventh (2010-2012; Follow-up) waves of the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) and completed a 3-day dietary weights recording survey at baseline. A table of taurine content was prepared for 751 foods (including five food groups: Seaweed; Fish and shellfish; Meat; Eggs; and Milk and dairy products) from the Standard Tables of Food Composition in Japan (1,878 foods) 2010. Four physical fitness items (knee extension muscle strength, sit-and-reach, one-leg standing with eyes closed, and maximum walking speed) were measured at baseline and follow-up. We analyzed the association of taurine intake with physical fitness change, employing a general linear model (GLM) and trend tests for baseline taurine intake and follow-up fitness change. Adjustments included baseline variables: sex, age, height, weight, educational level, self-rated health, smoking status, depressive symptoms, and clinical history. The estimated average daily taurine intake (standard deviation) was 207.5 (145.6) mg/day at the baseline. When examining the association with the four physical fitness parameters, higher taurine intake positively increased the change in knee extension muscle strength (T1; 0.1, T2; 0.8, T3; 1.1 (kgf) GLM, p < 0.05; p for trend <0.05) and reduced the decline in knee extension muscle strength in the subgroup analysis of participants aged ≥65 years (T1: -1.9, T2: -1.7, T3: -0.4 kgf; GLM p < 0.05, p for trend <0.05). No relationship was found between taurine intake and the remaining three fitness factors. Estimation of taurine intake showed that dietary taurine intake potentially contributes to the maintenance of knee extension muscle strength over 8 years among Japanese community-dwelling middle-aged and older individuals. This is the first study to investigate the association of dietary taurine intake with muscle strength.

Longitudinal association between muscle and bone loss: Results of US and Japanese cohort studies.

Muscle and bone are physiologically interconnected, but joint changes of muscle and bone with aging, and whether the muscle-bone changes are different by sex and by country has been little studied. We examined longitudinal associations of bone mineral density (BMD) and muscle mass or muscle strength in community-dwelling 65years or older in the United States and Japan. The present analytic sample included 1129 women and men from the Baltimore Longitudinal Study of Aging (BLSA) (mean age, 74.5±7.5years; women, 49.8%) and 1998 women and men from the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) (mean age, 70.0±4.5years; women, 51.4%). Median follow-up was 4.6 (min-max, 0-15.4) years in the BLSA and 4.0 (min-max, 0-13.4) years in the NILS-LSA. We selected visits at which participants had BMD (whole body, pelvic, femoral neck, trochanter, and Ward's triangle BMDs) and muscle mass [appendicular lean mass, (ALM)] measured by DXA scan. In each bone site, we ran cohort-specific bivariate linear mixed-effects models adjusted for baseline age, sex, body height, body weight, fat mass, education year, and smoking status. Race was an additional adjustment in the BLSA. Additionally, we performed sex-specific analyses. In the BLSA, the rate of change in ALM positively correlated with the rate of change in the whole body (rho=0.30, P<0.0001) and pelvic BMD (rho=0.24, P<0.0001), but not in trochanter, femoral neck, or Ward's triangle BMD (P>0.05). In the NILS-LSA, ALM positively correlated with the rate of change in all bone sites (rho ranged from 0.20 to 0.71, P<0.01). In women, ALM positively correlated with the rate of change in all bone sites in both cohorts (in the NILS-LSA, rho ranged from 0.35 to 0.91, P<0.01; in the BLSA, rho ranged from 0.26 to 0.56, P<0.05) except for femoral neck BMD in the BLSA. In men, ALM positively correlated with pelvic, trochanter, and Ward's triangle BMD in the NILS-LSA (rho ranged from 0.45 to 0.68, P<0.0001), and whole body and trochanter BMD in the BLSA (both, rho=0.20, P<0.05). Muscle loss co-occurred with bone loss in both cohorts, but the association in the NILS-LSA tended to be stronger than in the BLSA, and the association was higher in women than in men, implying that the association may differ by sex and country.

Implication of grip strength assessment for the management of body weight in disability prevention in older adults.

Although body mass index (BMI) and grip strength (GS) are both predictors of disability, their joint effect on predicting incident disability remains uncertain. We examined whether the effect of BMI on incident disability can be modulated by GS in community-dwelling older people in Japan. A total of 1486 community-dwellers in Japan (731 men and 755 women, aged 65-82years) who participated in the 2nd to 7th waves of the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) project, were followed up to 20years. Twelve subgroups were created according to the intersections of GS (sex-specific tertiles: low, intermediate, and high) and BMI (underweight 1, <18.5; underweight 2, 18.5-<21.5; normal, 21.5-<25.0; and overweight/obese, ≥25.0kg/m2 ). Incident disability was defined as requiring care need level 1 or higher, as per the long-term care insurance system in Japan. The hazard ratios (HR) and corresponding 95% confidence intervals (CI) of incident disability (the 'high GS-normal BMI' subgroup was used as the reference) were calculated using a multivariable-adjusted Cox proportional hazards model. The model was adjusted for baseline characteristics on sex, participation wave, smoking, depressive symptoms, total physical activity, disease history, education level, residential status, and energy intake. Compared with that for participants in the 'high GS-normal BMI' group, the risk of incident disability was higher for participants in the 'low GS-normal BMI', 'low GS-overweight/obese', 'intermediate GS-underweight 1' and 'intermediate GS-overweight/obese' groups. The multivariable-adjusted HR (95% CI) were 1.72 (1.27-2.32, P value<0.001), 1.81 (1.27-2.58, P value=0.001), 2.42 (1.35-4.32, P value=0.003) and 1.53 (1.06-2.20, P value=0.023), respectively. The results did not change substantially when participants with disability occurring within 1 and 2years of follow-up were excluded, or when the competing events were death without incident disability or dementia. The joint effect of BMI and GS was more pronounced in those of normal weight or overweight/obese status and low GS, along with underweight or overweight/obese status and intermediate GS in predicting disability. The lack of observed joint effect for those underweight with low GS was likely due to insufficient sample size. GS consideration is necessary for weight management in older adults, and interventions for individuals who are underweight or overweight/obese with adequate GS need not be prioritized for disability prevention.

Mushroom consumption and hyperuricemia: results from the National Institute for Longevity Sciences-Longitudinal Study of Aging and the National Health and Nutrition Examination Survey (2007-2018)

BackgroundPrior study reported that mushroom consumption was associated with a lower incidence of hyperuricemia, but there is limited evidence on this association. We conducted a collaborative study to investigate the association between mushroom intake and hyperuricemia in middle-aged and older populations.MethodsWe used data from the National Health and Nutrition Examination Survey (NHANES) in the U.S. (2007–2018) and the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) in Japan (1997–2012). Consumption of mushroom (g/day) were measured by one- or two-day dietary recall in NHANES and by 3-day dietary records in the NILS-LSA. Hyperuricemia was defined using uric acid levels as > 420 μmol/L and > 350 μmol/L in NHANES for men and women, respectively; in the NILS-LSA, serum uric acid was repeatedly measured at baseline and follow-up surveys. Hyperuricemia was defined as uric acid levels > 416.4 μmol/L for men and ≥ 356.9 μmol/L for women. Logistic regression models in NHANES (cross-sectionally) and Generalized Estimation Equations in NILS-LSA (longitudinally) were performed.ResultsA total of 5,778 NHANES participants (mean (SD) age: 53.2 (9.6) years) and 1,738 NILS-LSA (mean (SD) age: 53.5 (11.2) years) were included. Mushrooms were consumed by 5.7% of participants in NHANES and 81.2% in NILS-LSA. We did not observe a significant association between mushroom intakes and hyperuricemia in the NHANES men and women. However, in the NILS-LSA, compared to non-consumers, a higher mushroom intake was associated with a lower risk of incident hyperuricemia in men under 65 years old. The adjusted odds ratio (95% CI) for non-consumers, participants with middle, and the highest consumption of mushrooms were 1.00 (Ref.), 0.77 (0.44, 1.36), and 0.55 (0.31, 0.99), respectively (P-trend = 0.036). No association was found in women in NILS-LSA.ConclusionsMushroom consumption was associated with a lower risk of incident hyperuricemia in Japanese men.

Association of a lesser number of teeth with more risk of developing depressive symptoms among middle-aged and older adults in Japan: A 20-year population-based cohort study

ObjectivesThis 20-year prospective cohort study aimed to longitudinally explore the relationship between the number of teeth and the incidence of depressive symptoms among community-dwelling middle-aged and older adults. MethodsData were collected from the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) database from 2002 to 2022 (3rd–9th waves). Data of adults aged ≥40 years were analyzed and those who had depressive symptoms at baseline (3rd wave), had missing data, or did not participate in follow-up, were excluded. We collected data on the number of teeth at baseline. Depressive symptoms were defined as a score of ≥16 on the Center for Epidemiologic Studies Depression Scale. The generalized estimating equation (GEE) model was used to examine the longitudinal relationships between the number of teeth at baseline and the subsequent incidence of depressive symptoms. ResultsThe final analysis included 1668 participants, with a mean (standard deviation) age of 58.8 (11.1) years and a mean follow-up time of 12.9 years. After GEE analysis with adjustment for multiple covariates, compared to participants with ≥20 teeth, participants with 10–19 teeth and < 10 teeth at baseline were associated with a higher risk of depressive symptoms. The subgroup analysis showed that the effect was stronger in men than in women. ConclusionsAmong middle-aged and older community dwellers, particularly men, a small number of teeth after the age of 40 was associated with the future incidence of depressive symptoms.

Effect of different types of social support on physical frailty development among community-dwelling older adults in Japan: Evidence from a 10-year population-based cohort study

PurposeSocial support is associated with multiple positive health outcomes and is negatively associated with frailty in older adults. However, most evidence came from cross-sectional research. This study aimed to longitudinally explore the relationship between different types of social support and incident physical frailty. Materials and methodsA 10-year prospective cohort study data from the National Institute for Longevity Sciences – Longitudinal Study of Aging (NILS-LSA) database, from 2000 to 2012 on older adults aged ≥65 years were analyzed excluding those with physical frailty at baseline, missing data, or not attending follow-up. We measured three kinds of social support, whether from within or outside family members, including emotional, instrumental, and negative support. The generalized estimating equation (GEE) model was used to examine the longitudinal relationships between social support and subsequent frailty. ResultsThe final analysis included 466 participants, with an average age of 71.3 (standard deviation [SD], 4.3) years and 7.33 years of follow-up (SD, 3.11). GEE analysis showed that emotional and instrumental supports from within and outside family members were associated with a significantly lower risk of physical frailty (odd ratio (OR) and 95% confidence interval (CI): 0.80 [0.64–1.00] and 0.74 [0.58–0.95]; 0.77 [0.60–0.99] and 0.79 [0.63–0.99], respectively). Both negative support from within or outside family members had no significant relationship with the risk of physical frailty. ConclusionsThis longitudinal study suggested that emotional, and instrumental support both from within or outside family members can reduce future physical frailty among older adults.

Effects of APOEɛ4 genotype on age-associated change in cognitive functions among Japanese middle-aged and older adults: A 20-year follow-up study

Background and aimsCarriers 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. Methods and resultsThe 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). ConclusionsAPOEɛ4 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.

Serum levels of dehydroepiandrosterone sulfate are associated with a lower risk of mobility-subtype frailty in older Japanese community-dwellers

PurposePrevious studies suggest that lower serum levels of dehydroepiandrosterone sulfate (DHEA-S) are associated with physical frailty. Associations with subtypes of physical frailty have not been studied. This study aimed to investigate associations between serum DHEA-S levels and physical frailty and its subtypes in older Japanese community-dwellers using panel data. MethodsThis study was conducted within the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA). Repeated measurement data were collected from 1,886 older community-dwellers (60–91 years). Frailty was identified according to modified Cardiovascular Health Study criteria (weight loss, weakness, slowness, exhaustion, low physical activity) and was classified into following subtypes: mobility (weakness/slowness), non-mobility (weight loss/exhaustion), and low physical activity. Associations with serum DHEA-S (sex-specific tertiles [T1−T3]) were estimated by random-effects logistic regression models adjusting for age, sex, education, disease history (stroke, hypertension, heart disease, diabetes), smoking status, depressive symptoms, and survey wave. ResultsWe found an average prevalence of 6.0% for frailty (mobility subtype, 7.0%; non-mobility subtype, 34.8%; low physical activity subtype, 9.4%) across survey waves. Mean (SD) sex-specific DHEA-S levels (μg/dL) at T1, T2, and T3 were 46.8 (20.8), 88.7 (28.4), and 158.0 (58.9), respectively. Compared with T1, the adjusted ORs (95% CIs) for frailty were 0.69 (0.44, 1.08) for T2 and 0.50 (0.30, 0.83) for T3 (P trend = 0.007). The corresponding values for mobility subtype were 0.80 (0.51, 1.24) for T2 and 0.55 (0.33, 0.90) for T3. ConclusionHigher serum DHEA-S levels were associated with lower risk of frailty, especially mobility-subtype frailty, in older community-dwellers.

Interaction between cognitive leisure activity and long-chain polyunsaturated fatty acid intake on global cognitive decline in a Japanese longitudinal cohort study: National Institute for Longevity Sciences-Longitudinal Study of Aging

BackgroundThere 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.MethodsThe 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.ResultsA 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)].ConclusionsPreserving cognitive function might be associated with a combination of varied and high-frequency engagement in CLAs combined with high LCPUFA intake.

Green tea consumption is associated with annual changes in hippocampal volumes: A longitudinal study in community-dwelling middle-aged and older Japanese individuals

BackgroundTo 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. MethodsA 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. ResultsThe 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. ConclusionsIn 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.

Protein intake per day and at each daily meal and skeletal muscle mass declines among older community dwellers in Japan.

To examine associations between protein intake per day and at different meals and skeletal muscle mass declines. Two-year prospective cohort study among older community dwellers. National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) in Japan. Older men (n 292) and women (n 363) aged 60-87 years who participated in the baseline (2006-2008) and follow-up studies (2008-2010) of NILS-LSA and did not exhibit low skeletal muscle mass at baseline. Muscle mass was assessed using dual-energy X-ray absorptiometry at baseline and follow-up. Low muscle mass was defined as skeletal muscle mass index <7·0 kg/m2 for men and <5·4 kg/m2 for women at follow-up. Daily protein intake and protein intake at each meal were calculated from 3 d dietary records at baseline and sex-stratified tertiles were determined. Mean (sd) protein intake at breakfast, lunch and dinner was 22·7 (7·8), 26·7 (9·3) and 37·4 (10·5) g for men and 19·3 (6·3), 23·2 (7·3) and 28·5 (7·0) g for women, respectively. After adjusting for age, baseline skeletal muscle mass and other confounders in logistic modelling, greater total protein intake was associated with lower prevalence of skeletal muscle mass decline among men at follow-up (P = 0·024). Particularly, the OR (95 % CI) for high lunchtime protein intake was low (0·11 (0·02, 0·61); P = 0·01). No significant association between total protein intake and prevalence of skeletal muscle mass decline was found among women. High total protein intake, particularly at lunchtime, is associated with retention of skeletal muscle mass in men.

Green tea and coffee intake and risk of cognitive decline in older adults: the National Institute for Longevity Sciences, Longitudinal Study of Aging.

To examine the association between green tea and coffee intake and cognitive decline in older adults. 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 <27 points was obtained in a biennial test from the baseline. Hazard ratios for incidence of cognitive decline were estimated according to the intake of the two beverages using multivariable Cox proportional hazard regression, controlling for sociodemographic and lifestyle factors. The National Institute for Longevity Sciences, Longitudinal Study of Aging (NILS-LSA) in Japan. Men (n 620) and women (n 685), aged 60-85 years, from the NILS-LSA. 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 <once/d, the multivariable hazard ratio (95 % CI) was 0·70 (0·45, 1·06), 0·71 (0·52, 0·97) and 0·72 (0·54, 0·98) among those who consumed green tea once/d, 2-3 times/d and ≥4 times/d, respectively (Ptrend < 0·05). No significant association was found between coffee intake and cognitive decline. The intake of green tea, but not coffee, was shown to reduce the risk of cognitive decline in older adults.

Dietary factors associated with the development of physical frailty in community-dwelling older adults.

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.

Prevalence and Risk Factors of MRI Abnormality Which Was Suspected as Sinusitis in Japanese Middle-Aged and Elderly Community Dwellers.

The aims of this study were to determine the prevalence of MRI abnormalities which were suspected as sinusitis in community-dwelling middle-aged and elderly Japanese and to identify risk factors for the MRI abnormality. Brain magnetic resonance imaging (MRI) data from the National Institute for Longevity Sciences, Longitudinal Study of Aging (NILS-LSA) were used for the analysis. Among the 2330 subjects in the NILS-LSA, 1933 participants were categorized as having no MRI abnormality or MRI abnormality using the Lund-Mackay (LM) score. The mean LM score of the participants was 0.88±1.92, and 144 (7.4%) participants had MRI abnormalities which were suspected as sinusitis when it was classified as an LM score greater than or equal to 4. The prevalence of MRI abnormality was significantly higher in participants of older age and the male sex, in participants with obesity, hypertension, bronchial asthma, chronic bronchitis, gout, or hyperuricemia and in ex- or current smokers. A multivariate logistic regression revealed that older age (odds ratio [OR] = 1.17), obesity (OR = 1.54), a smoking habit (OR = 1.71), history of asthma (OR = 3.77), and chronic bronchitis (OR = 2.66) were significant risk factors for MRI abnormality.

Age-related Changes in Energy Intake and Weight in Community-dwelling Middle-aged and Elderly Japanese.

This study attempts to describe trends in energy intake and weight change over 12 years according to age at first participation in the study. Prospective cohort study. The National Institute for Longevity Sciences - Longitudinal Study of Aging (NILS-LSA), a community-based study. Participants included 922 men and 879 women who participated in the first study-wave (age 40-79 years) and also participated in at least one study-wave from the second to seventh study-wave. Each study-wave was conducted biennially. For individuals, the entire follow-up period was 12 years. Energy intake was calculated from 3-day dietary records with photographs. Weight and height were measured under a fasting state. To estimate linear changes in energy intake and weight over 12 years according to age at first study-wave, we used the mixed-effects model. Mean (SD) follow-up time and number of study-wave visits were 9.5 (3.7) years and 5.4 (1.8) times, respectively. The fixed effect of the interaction of age and time in energy intake and weight was statistically or marginally statistically significant both in men (p<0.01) and in women (p<0.06). In men, when energy intake was estimated according to age, the rate of decrease in energy intake increased from -6.8 to -33.8 kcal/year for ages 40-79 years. In women, the rate of decrease in energy intake slightly increased in older age groups (-9.1 to -16.7 kcal/year for ages 40-79 years). Weight increased in males in their 40s (0.07 kg/year from age 40) and started to decline by age 53. In women, weight started to decline around age 47 (-0.04 kg/year). Twelve-year longitudinal data showed energy intake declined both in men and women in their 40s, and the rate of decrease increased in older males. Weight started to decline in men in their mid-50s and women in their late 40s. Further studies that focus on energy intake and weight reduction are needed to prevent weight loss or underweight in an increasingly aging society.

Prevalence of Sinusitis Detected by Magnetic Resonance Imaging in Subjects with Dementia or Alzheimer's Disease.

It has been reported that periodontitis is associated with Alzheimer's disease. However, the association between paranasal sinusitis and Alzheimer's disease has not been studied, although olfactory dysfunction frequently precedes the progress of dementia or Alzheimer's disease. We studied 783 patients (283 men, 500 women; mean age 77.0 ± 7.9 years) who visited the Center for Comprehensive Care and Research on Memory Disorders, National Center for Geriatrics and Gerontology, and 2139 control subjects who participated in a population-based study conducted by the National Institute for Longevity Sciences - Longitudinal Study of Aging (NILS-LSA) in Japan. Sinusitis was evaluated using magnetic resonance imaging (MRI) according to the Lund-Mackay scoring system. A sinusitis score of ≥ 4 was classified as positive and a score of ≤ 3 was classified as negative. The prevalence of positive sinusitis was 6.3% in patients with a mini-mental state examination (MMSE) score of < 24 (n = 507), and 5.7% in patients with Alzheimer's disease (n = 280). The rate of positive sinusitis was7.2% in the control group. The prevalence of sinusitis was not significantly different between normal controls and patients with dementia or Alzheimer's disease after adjustments for age and sex. The rate of positive sinusitis was higher in male than in female subjects in both groups. The prevalence of sinusitis in patients with Alzheimer's disease or dementia was not higher than in the general population.

Does high educational level protect against intellectual decline in older adults?: A 10‐year longitudinal study

AbstractThis study examined the relation between educational level and intellectual change in Japanese older adults. Participants (age = 65–79 years, n = 593) comprised the first‐wave participants of the National Institute for Longevity Sciences‐Longitudinal Study of Aging (NILS‐LSA). They were followed for 10 years and were tested six times. Educational levels were divided into two groups (low‐educated or high‐educated), and intellectual changes for the 10 years were assessed using the Japanese Wechsler Adult Intelligence Scale‐Revised Short Forms (JWAIS‐R‐SF); subtests included Information, Similarities, Picture Completion, and Digit Symbol. General linear mixed‐model analyses revealed that education had not affected 10‐year changes of the Information, Similarities, and Picture Completion subtest scores. In contrast, education was significantly associated with a change in the Digit Symbol subtest score; individuals with higher levels of education showed greater decline than those with less education, although they had higher ability at every time point. These findings suggest that higher education does not protect against intellectual decline in late life, although it is associated with long‐term individual differences in intelligence.

高齢者の耳垢の頻度と認知機能，聴力との関連

In this study we aimed to evaluate the frequency of cerumen impaction in Japanese elderly and clarify the associations between cerumen, cognitive function, and hearing impairment. The subjects enrolleded in this study were participants in the National Institute for Longevity Sciences, Longitudinal Study of Aging (NILS-LSA). The data of 792 community-dwelling participants aged 60 to 88 years old were collected. All had taken the Mini-Mental State Examination (MMSE) and had undergone pure tone audiometry (PTA) assessment and video recording of an otoscopic examination. We then analyzed associations between the incidence of the cerumen impaction of better-hearing ear, hearing level and MMSE scores using a general linear model. Cerumen impaction of the better-hearing ear was observed in 10.7% of all participants. In participants with an MMSE score of less than 24, the frequency of cerumen impaction was 23.3%. Cerumen was significant associated with poorer hearing after adjustment for sex and age (p=0.0001). Cerumen impaction also showed a significant association with a low MMSE score after adjustment for sex, age, hearing level and education (p=0.02). The frequency of cerumen impaction in Japanese elderly was estimated to be approximately 10%. The existence of cerumen impaction was associated with poorer hearing level and lower MMSE score.

全国高齢難聴者数推計と10年後の年齢別難聴発症率―老化に関する長期縦断疫学研究（NILS-LSA）より

The number of hearing-impaired elderly people in Japan remains to be clarified. In the present study, we analyzed the data from the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA) to ascertain the prevalence and 10-year incidence of hearing loss in Japanese elderly people. Hearing loss prevalence was calculated based on 2,194 subjects who had been included in the 6th survey of the NILS-LSA (2008-2010) and was represented as crude rates (calculation A) and as rates after the exclusion of occupational noise-exposure and ear disease history (calculation B). Estimates of hearing loss incidence were performed at a national level based on demographic statistics. Subsequently, we analyzed the 10-year incidence in 465 subjects showing no hearing loss at baseline (1997-2000 survey) all of whom also participated in the 6(th) survey of the NILS-LSA (2008-2010). The prevalence of hearing loss greatly increased after the age of 65 years. The prevalence observed in calculation A was 43.7%, 51.1%, 71.4%, and 84.3% in men aged 65-69, 70-74, 75-79, and over 80 years old, respectively. In women, the prevalence for the same age groups was 27.7%, 41.8%, 67.3%, and 73.3%, respectively. The size of the hearing-impaired population older than 65 years old was estimated to be 16,553,000. The 10-year incidence rates of hearing impairment in the 60-64- and 70-74-year-old age groups were 32.5% and 62.5% (age at baseline), respectively. These rates rapidly increased with age, although a number of elderly people with good hearing were also observed. Age-related hearing loss is an issue of national importance. These results also indicated that it is possible to preserve good hearing into later in life, and that hearing loss in the elderly may be preventable.

Spatiotemporal components of the 3-D gait analysis of community-dwelling middle-aged and elderly Japanese: Age- and sex-related differences

To describe age- and sex-related differences in gait patterns of community-living men and women using 3-D gait analysis. Subjects (n=2006) aged 40-84 years participated in the National Institute for Longevity Sciences-Longitudinal Study of Aging (NILS-LSA). Spatiotemporal components, including velocity, step length, step frequency, and double support time during a gait cycle, were calculated from 3-D coordinates and vertical force data. Velocity, step length and step frequency were normalized by leg length and acceleration due to gravity, and double support time was normalized to gait cycle duration. Spatiotemporal walking variables of brisk velocity and step length were significantly greater in men than in women, while comfortable velocity and comfortable and brisk step frequencies and double support times were greater in women than in men. Age-related changes were marked at 70-84 years in most spatiotemporal variables in both sexes during comfortable walking. During brisk walking, age-related changes were observed from a younger age than during comfortable walking, and there were sex-related differences. The age-related gait alteration was obvious among those aged 70 years and older, and it accelerated markedly in women's brisk walking intensity.