Journals of Gerontology Series A-Biological Sciences and Medical Sciences最新文献

Background: Little is known about how depressive symptoms and glial fibrillary acid protein (GFAP) concentrations taken together may influence cognitive functioning. Understanding this relationship may inform strategies for screening and early intervention to decrease the rate of cognitive decline.

Methods: This study sample includes 1 169 participants from the Chicago Health and Aging Project (CHAP), consisting of 60% Black participants and 40% White participants, and 63% female participants and 37% male participants. CHAP is a population-based cohort study of older adults with a mean age of 77 years. Linear mixed-effects regression models tested the main effects of depressive symptoms and GFAP concentrations and their interactions on baseline cognitive function and cognitive decline over time. Models included adjustments for age, race, sex, education, chronic medical conditions, body mass index, smoking status, alcohol use, and their interactions with time.

Results: The interaction of depressive symptomology and GFAP (β = -0.105 [standard error = 0.038], p = .006) on global cognitive function was statistically significant. Participants with depressive symptoms including and above the cutoff and high log of GFAP concentrations had more cognitive decline over time, followed by participants with depressive symptoms below the cutoff and high log of GFAP concentrations, depressive symptom scores including and above the cutoff and low log of GFAP concentrations, and depressive symptom scores below the cutoff and low log of GFAP concentrations.

Conclusions: Depressive symptoms have an additive effect on the association between the log of GFAP and baseline global cognitive function.

People age differently. Differences in aging might be reflected by metabolites, also known as metabolomic aging. Predicting metabolomic aging is of interest in public health research. However, the added value of longitudinal over cross-sectional predictors of metabolomic aging is unknown. We studied exposome-related exposures as potential predictors of metabolomic aging, both cross-sectionally and longitudinally in men and women. We used data from 4 459 participants, aged 36-75 of Round 4 (2003-2008) of the long-running Doetinchem Cohort Study (DCS). Metabolomic age was calculated with the MetaboHealth algorithm. Cross-sectional exposures were demographic, biological, lifestyle, and environmental at Round 4. Longitudinal exposures were based on the average exposure over 15 years (Round 1 [1987-1991] to 4), and trend in these exposure over time. Random Forest was performed to identify model performance and important predictors. Prediction performances were similar for cross-sectional and longitudinal exposures in both men (R2 6.8 and 5.8, respectively) and women (R2 14.8 and 14.4, respectively). Biological and diet exposures were most predictive for metabolomic aging in both men and women. Other important predictors were smoking behavior for men and contraceptive use and menopausal status for women. Taking into account history of exposure levels (longitudinal) had no added value over cross-sectionally measured exposures in predicting metabolomic aging in the current study. However, the prediction performances of both models were rather low. The most important predictors for metabolomic aging were from the biological and lifestyle domain and differed slightly between men and women.

Background: We investigated the associations between habitual use of glucosamine and incident dementia and Parkinson's disease in a population-based cohort.

Methods: Using the UK Biobank data, we included around 0.29 million middle- to old-aged participants free of dementia or Parkinson's disease at baseline. Glucosamine supplementation was measured by questionnaire at baseline. Some participants additionally answered 1-5 rounds of 24-hour dietary recalls afterwards, particularly 112 243 participants (for dementia) and 112 084 (for Parkinson's disease). Incident cases of dementia and Parkinson's disease were identified through linkage to health administrative data sets. We examined the associations of glucosamine supplementation with incident dementia and Parkinson's disease using Cox proportional-hazards regression models with adjustment for various covariates.

Results: During the study period (median follow-up: 9.1-10.9 years), 4 404 and 1 637 participants developed dementia and Parkinson's disease, respectively. Glucosamine intake was not associated with incident dementia or Parkinson's disease. In fully adjusted models, the hazard ratios associated with glucosamine intake were 1.06 [95% confidence interval (CI): 0.99, 1.14] for dementia and 0.97(95% CI: 0.86, 1.09) for Parkinson's disease. In the subsample, similar results were found as the frequency of reported glucosamine use over multiple dietary surveys was associated with neither of the 2 conditions.

Conclusions: Habitual supplementation of glucosamine was not associated with incident dementia or Parkinson's disease.

Background: Researchers are increasingly interested in better methods for assessing the pace of aging in older adults, including vocal analysis. The present study sought to determine whether paralinguistic vocal attributes improve estimates of the age and risk of mortality in older adults.

Methods: To measure vocal age, we curated interviews provided by male U.S. World War II Veterans in the Library of Congress collection. We used diarization to identify speakers and measure vocal features and matched recording data to mortality information. Veterans (N = 2 447) were randomly split into testing (n = 1 467) and validation (n = 980) subsets to generate estimations of vocal age and years of life remaining. Results were replicated to examine out-of-sample utility using Korean War Veterans (N = 352).

Results: World War II Veterans' average age was 86.08 at the time of recording and 91.28 at the time of death. Overall, 7.4% were prisoners of war, 43.3% were Army Veterans, and 29.3% were drafted. Vocal age estimates (mean absolute error = 3.255) were within 5 years of chronological age, 78.5% of the time. With chronological age held constant, older vocal age estimation was correlated with shorter life expectancy (aHR = 1.10; 95% confidence interval: 1.06-1.15; p < .001), even when adjusting for age at vocal assessment.

Conclusions: Computational analyses reduced estimation error by 71.94% (approximately 8 years) and produced vocal age estimates that were correlated with both age and predicted time until death when age was held constant. Paralinguistic analyses augment other assessments for individuals when oral patient histories are recorded.

Background: There is a scarcity of studies examining the longitudinal relationship between dynapenic abdominal obesity (DAO; ie, impairment in muscle strength and high waist circumference) and future fall risk. Therefore, we aimed to investigate the prospective association between DAO at baseline and falls occurring during 2 years of follow-up in a nationally representative sample of middle-aged and older individuals from Ireland.

Methods: Data from 2 consecutive waves of the Irish Longitudinal Study on Ageing survey were analyzed. Dynapenia was defined as handgrip strength of <26 kg for men and <16 kg for women. Abdominal obesity was defined as a waist circumference of >88 cm for women and >102 cm for men. DAO was assessed at Wave 1 (2009-2011) and was defined as having both dynapenia and abdominal obesity. Falls occurring between Wave 1 and Wave 2 (2012-2013) were self-reported. Multivariable logistic regression analysis was conducted.

Results: Data on 5 275 individuals aged ≥50 years were analyzed (mean [standard deviation {SD}] age 63.2 [8.9] years; 48.8% males). After adjustment for potential confounders, compared to no dynapenia and no abdominal obesity at baseline, DAO was significantly associated with 1.47 (95% confidence interval [CI]: 1.14-1.89) times higher odds for falls at 2-year follow-up. Dynapenia alone (odds ratio [OR] = 1.08; 95% CI: 0.84-1.40) and abdominal obesity alone (OR = 1.09; 95% CI: 0.91-1.29) were not significantly associated with falls at follow-up.

Conclusions: DAO increased the risk for falls among middle-aged and older adults in Ireland. Interventions to prevent or reverse DAO may be beneficial for fall reduction.

Background: The association between serum uric acid (SUA) and cognitive function remains unclear, especially among individuals without hyperuricemia. We examined the cross-sectional and longitudinal bidirectional associations between SUA and cognition, as well as the mediating effect of depressive symptoms among Chinese adults.

Methods: Data were obtained from the China Health and Retirement Longitudinal Study (CHARLS). SUA (continuous) and cognitive function (based on mental intactness and episodic memory) were measured at Wave 1 and Wave 3. Depressive symptoms (Center for Epidemiologic Studies Depression scale) were assessed at Wave 1. Bivariate latent change score models and mediation analysis were used to investigate these possible associations.

Results: A total of 6 236 participants free of hyperuricemia (aged 58.3 ± 8.5 years) were included. After controlling for potential confounders, the SUA level was associated with cognition at baseline (standardized r = 0.042; p = .001). Higher baseline SUA level was associated with slower subsequent cognitive decline (standardized β = 0.026; p = .027), whereas baseline cognition was not significantly associated with subsequent change in SUA (standardized β = 0.003; p = .817). In mediation analysis, baseline SUA was indirectly associated with subsequent cognition via baseline depressive symptoms (mediation effect 13.3%; p < .001).

Conclusions: Higher baseline SUA level is associated with better baseline cognition and less subsequent cognitive decline among Chinese adults without hyperuricemia. Baseline depressive symptoms may partially mediate the association between baseline SUA and later cognition. Continued research is warranted to verify these findings and elucidate the causality and underlying mechanisms.

Background: A decade ago, we proposed an index of physiological dysregulation based on Mahalanobis distance (DM) that measures how far from the norm an individual biomarker profile is. While extensive validation has been performed, focus was mostly on Western populations with little comparison to developing countries, particularly at a physiological system level. The degree to which the approach would work in other sociocultural contexts and the similarity of dysregulation signatures across diverse populations are still open questions.

Methods: Using 2 data sets from China and 3 from Western countries (United States, United Kingdom, and Italy), we calculated DM globally and per physiological system. We assessed pairwise correlations among systems, difference with age, prediction of mortality and age-related diseases, and sensitivity to interchanging data sets with one another as the reference in DM calculation.

Results: Overall, results were comparable across all data sets. Different physiological systems showed distinct dysregulation processes. Association with age was moderate and often nonlinear, similarly for all populations. Mahalanobis distance predicted most health outcomes, although differently by physiological system. Using a Chinese population as the reference when calculating DM for Western populations, or vice versa, led to similar associations with health outcomes, with a few exceptions.

Conclusions: While small differences were noticeable, they did not systematically emerge between Chinese and Western populations, but rather diffusively across all data sets. These findings suggest that DM presents similar properties, notwithstanding sociocultural backgrounds, and that it is equally effective in capturing the loss of homeostasis that occurs during aging in diverse industrial human populations.

Background: Many studies reported that lifestyle, psychosocial characteristics, and sleep status related to sarcopenia, although few studies provided evidence of causal relationships between them.

Methods: The data used in our study were from UK Biobank, FinnGen Release 8, and large genome-wide association study meta-analyses. Two-sample Mendelian randomization was conducted to identify the causal associations of 21 traits of lifestyle, psychosocial characteristics, and sleep status with 6 traits of sarcopenia. Benjamini-Hochberg correction was performed to reduce the bias caused by multiple tests. Risk factor analyses were performed to explore the potential mechanism behind the exposures.

Results: Mendelian randomization analyses after adjustment proved the causal roles of coffee intake, education years, smoking, leisure screen time, and moderate-to-vigorous intensity physical activity during leisure time in sarcopenia was proven although providing no significant evidence for causal roles for carbohydrates intake, protein intake, alcohol, and sleep status in sarcopenia.

Conclusions: Our results strongly support that coffee intake, education years, smoking, leisure screen time, and moderate-to-vigorous intensity physical activity during leisure time played significantly causal roles in sarcopenia, which may provide new intervention strategies for preventing the development of sarcopenia.

Background: Hearing loss is associated with adverse health outcomes among older adults. Lower physical activity levels may partly explain these observations, yet the association between hearing loss, hearing aid use, and physical activity among older adults is understudied.

Methods: Cross-sectional analysis of National Health and Aging Trends Study (2021) participants. The better-hearing ear pure-tone average (BPTA) at speech frequencies (0.5-4 kHz) was modeled continuously (10-dB increments) and categorically (no: ≤25 dB, mild: 26-40 dB, moderate or greater: >40 dB hearing loss). Activity measures were wrist accelerometry-derived (Actigraph) total activity counts, daily active minutes, activity fragmentation (using active-to-sedentary transition probability), and self-reported participation in vigorous activities and walking for exercise in the last month. We used multivariable regression adjusted for sociodemographic and health covariates.

Results: Among 504 participants excluding hearing aid users (mean age = 79 years, 57% female, 9% Black), 338 (67%) had hearing loss. Worse hearing (continuously and categorically) was associated with fewer counts and active minutes, more fragmented activity, and greater odds of not reporting recent vigorous activities. Among 472 participants with hearing loss including hearing aid users, nonusers (n = 338) had more fragmented activity and greater odds of not reporting walking for exercise compared to users.

Conclusions: Older adults with hearing loss are less physically active. This may mediate the association between hearing loss and other adverse outcomes. Recognition of this potential association is essential for providers to better support older adults in maintaining an active lifestyle. Future research is warranted to understand the impact of hearing interventions.

Background: Childhood disadvantage is a prominent risk factor for cognitive and brain aging. Childhood disadvantage is associated with poorer episodic memory in late midlife and functional and structural brain abnormalities in the default mode network (DMN). Although age-related changes in DMN are associated with episodic memory declines in older adults, it remains unclear if childhood disadvantage has an enduring impact on this later-life brain-cognition relationship earlier in the aging process. Here, within the DMN, we examined whether its cortical microstructural integrity-an early marker of structural vulnerability that increases the risk for future cognitive decline and neurodegeneration-is associated with episodic memory in adults at ages 56-66, and whether childhood disadvantage moderates this association.

Methods: Cortical mean diffusivity (MD) obtained from diffusion magnetic resonance imaging was used to measure microstructural integrity in 350 community-dwelling men. We examined both visual and verbal episodic memory in relation to DMN MD and divided participants into disadvantaged and nondisadvantaged groups based on parental education and occupation.

Results: Higher DMN MD was associated with poorer visual memory but not verbal memory (β = -0.11, p = .040 vs β = -0.04, p = .535). This association was moderated by childhood disadvantage and was significant only in the disadvantaged group (β = -0.26, p = .002 vs β = -0.00, p = .957).

Conclusions: Lower DMN cortical microstructural integrity may reflect visual memory vulnerability in cognitively normal adults earlier in the aging process. Individuals who experienced childhood disadvantage manifested greater vulnerability to cortical microstructure-related visual memory dysfunction than their nondisadvantaged counterparts who exhibited resilience in the face of low cortical microstructural integrity.