The journals of gerontology. Series A, Biological sciences and medical sciences最新文献

Background: Poor oral health among older adults may contribute to cardiovascular and dementia risk via systemic inflammation and cardiometabolic comorbidities. Financial constraints are a major driver of unmet dental care needs for older individuals. This study investigates whether having dental care needs that were unmet due to cost is associated with subsequent incidence of cardiovascular disease (CVD) or dementia among adults aged 55 and older.

Methods: Participants in the All of Us cohort (N = 98,787) who responded to a survey question on dental care needs that were unmet due to cost were followed up to 5.3 years via electronic health records for onset of myocardial infarction (MI), stroke, heart failure (HF), or dementia. We estimated outcome-specific hazard ratios (HRs), using Cox proportional-hazards models, adjusting for demographic, behavioral, and clinical covariates.

Results: After adjustment for demographic factors, individuals who reported unmet dental needs due to cost had relatively higher incidence of HF (HR = 1.45; 95% CI: 1.30, 1.63), MI (HR = 1.37; 95% CI: 1.17, 1.61), stroke (HR = 1.45; 95% CI: 1.24, 1.70), and dementia (HR = 1.37; 95% CI: 1.05, 1.76). These associations were attenuated after further adjusting for socioeconomic, behavioral, and clinical factors. We did not observe differences by gender, racial and ethnic identity, or periodontitis diagnosis. The estimated population attributable fraction suggested that eliminating financial barriers to dental care could prevent 2-4% of each outcome among older adults.

Conclusion: Financial barriers to dental care may be an important determinant of CVD and dementia among aging populations.

Background: Multiple exercise modalities are recommended for older adults, yet their comparative effectiveness remains uncertain. We conducted a Bayesian network meta-analysis of randomized trials to compare common exercise modes on cardiorespiratory fitness and metabolic health in adults aged ≥55 years.

Methods: Trials randomized participants to high-intensity interval training (HIIT), aerobic training (AT), resistance training (RT), combined aerobic-resistance training (CART), or non-exercise control. The primary outcome was maximal/peak oxygen uptake (VO2max/VO2peak). Secondary outcomes included BMI, body fat percentage, fat-free mass, systolic/diastolic blood pressure, and blood lipids. We fitted random-effects Bayesian network meta-analysis models and summarized ranking probabilities using SUCRA.

Results: No exercise modality showed a clear advantage for VO2max/VO2peak; credible intervals were wide for most between-modality comparisons. Versus control, RT increased fat-free mass, CART reduced body fat percentage and systolic blood pressure, and HIIT reduced BMI and triglycerides. For total cholesterol, LDL-C, HDL-C, and diastolic blood pressure, credible intervals generally included the null. Heterogeneity was moderate, and formal inconsistency assessment was limited by sparse networks.

Conclusions: Current evidence does not identify a single "best" exercise modality for improving VO2max/VO2peak in older adults. Modality selection may be better guided by the primary goal (e.g., RT for lean mass, CART for adiposity and systolic blood pressure, HIIT for BMI and triglycerides), while considering feasibility and safety. Larger, well-reported head-to-head trials are needed to strengthen comparative estimates.

Aging clocks based on routine clinical indicators have emerged as a cost-effective tool for assessing biological age. This systematic review aims to summarize the characteristics and critically appraise these available aging clocks. Studies that developed aging clocks for adults (≥18 years) based on routine clinical indicators were retrieved from six databases (PubMed, EMBASE, Web of Science, CNKI, Wanfang Data, and Sinomed) up to June 18, 2024. The PROBAST+AI tool was used to assess the methodological quality, risk of bias, and applicability of included aging clocks. All the results were narratively summarized. Fifty-nine studies involving 81 aging clocks were included, of which 71 (87.7%) were developed using single-country datasets predominantly from China, the United States, Korea, and the United Kingdom. Notably, 31 aging clocks (38.3%) were developed with neither internal nor external validation. The majority of aging clocks were rated as having high concern regarding quality and high risk of bias, even including those published in high-impact journals. Only three aging clocks (3.7%) from two studies were rated as having low concern regarding quality and applicability during development, and two of these (4.0%) from one study further demonstrated low risk of bias and low concern for applicability during model evaluation. Future research should prioritize validating the promising aging clocks in target populations rather than developing new ones, adhere to the PROBAST+AI and TRIPOD+AI guidelines for methodological rigor and transparent reporting, and provide reproducible and user-friendly model codes and tools.

Background: Characterizing the correlates of adult mortality can lend insights into the factors associated with consequential health outcomes among older adults. In India, the importance of adult mortality has grown given trends in population aging, but prior research has been limited by a lack of high-quality longitudinal data.

Methods: We used new data from Waves 1 (2017-2019) and 2 (2022-2024) of the Longitudinal Aging Study in India-Diagnostic Assessment of Dementia (LASI-DAD) study (N = 3,871) to evaluate associations between all-cause mortality and 27 socioeconomic and clinical factors using Cox proportional hazards models. We also evaluated gender differences and the impact of COVID-19.

Results: The estimated mortality rate was 6.0 (95% CI 5.6-6.4) deaths per 100 person-years. A broad range of factors were associated with mortality, but cardiometabolic and cognitive phenotypes had some of the strongest associations; those with dementia had a 2.84 (95% CI 2.12-3.81) times greater risk of death than those with normal cognitive functioning. Associations with socioeconomic factors tended to be stronger for men than women (e.g., wealth quintile; χ2 p = 0.046), whereas associations with clinical factors tended to be stronger for women than men (e.g., diabetes; χ2 p = 0.033). We observed some evidence of excess mortality due to COVID-19.

Conclusion: Findings emphasize the multifaceted nature of health among older adults in India and illustrate the need for solutions that recognize the importance of a wide range of social factors and clinical health conditions. Results also showcase the importance of dementia as a key factor associated with survival among older adults.

The cerebellum, traditionally recognized for motor coordination, may also contribute to cognitive and emotional regulation, as recent evidence indicates. However, the molecular and structural changes in the human cerebellum during healthy aging remain poorly understood. This study systematically investigated the molecular trajectories and structural alterations in the human cerebellum across the adult lifespan (20-80 years) by integrating cerebella transcriptomic data from 456 non-disease brains and MRI structural neuroimaging data from 264 disease-free subjects. Fuzzy clustering analyses uncovered nonlinear expression trajectories involving synaptic plasticity, metabolic regulation, and protein homeostasis, highlighting multiple critical biological turning points across different age periods. Differential gene expression analyses identified early downregulation of immediate early genes (e.g., FOS, NPAS4, EGR1-3) and sustained activation of stress-response pathways changes that precede observable functional decline. Moreover, we identified an integrated "synaptic plasticity-stress homeostasis" module, where IEGs and heat shock proteins exhibit coordinated regulation whose efficiency progressively declines with age. MRI analyses showed a pronounced acceleration of cerebellar gray matter loss after age 70, with multiple subregions affected, highlighting the nonlinear trajectory of cerebellar structural aging. In combination with the transcriptomic findings, these results indicate that cerebellar aging comprises complex, stage dependent molecular alterations accompanied by gray matter reductions in later decades. This collective evidence advances our understanding of cerebellar aging biology and highlights the synaptic-stress module as a promising molecular axis that may inform future strategies to support cerebellar function in older adults.

Background: Obesity increases risks for mobility limitations and disability in older adults. We examined the long-term effects of an intensive lifestyle intervention (ILI) versus diabetes support and education (DSE) and body mass index (BMI) on disability.

Methods: Disability was assessed using the Pepper Assessment Tool for Disability (PAT-D) over four post-trial visits in Look AHEAD participants with type 2 diabetes and overweight/obesity. Disability and severe disability were defined as self-reporting "a lot of difficulty" or "unable" to perform ≥1 and ≥3 activities, respectively, on PAT-D subscales for mobility, instrumental, and basic activities of daily living (IADLs and BADLs). Associations between intervention group and BMI with disability prevalence were analyzed with GEE regression models, adjusting for demographics, multimorbidity index, cognition, physical performance, and diabetes control.

Results: Among 1191 participants at the first post-trial visit, mean (±SD) age was 68.7 ± 5.7 years, BMI was 34.4 ± 6.1 kg/m2; 61% were female, 69% White, and 52% assigned to ILI. Over nine years of follow-up, odds of severe mobility disability were higher for ILI participants aged ≥70 years (OR [95% CI]: 1.50 [1.02-2.20]) but lower for those in ILI <70 years (0.69 [0.48-0.99]) compared to controls (interaction p = .0043). Participants with BMI ≥35 kg/m2 had higher odds of mobility disability (2.06 [1.57-2.70]), severe mobility disability (2.52 [1.79-3.56]), and IADL disability (OR [95% CI]: 2.15 [1.53-3.02]) compared to those with BMI <30 kg/m2.

Conclusion: ILI was associated with greater severe mobility disability in participants ≥70. Regardless of age, those with higher BMI had increased late-life mobility and IADL disability.

Background: Adverse childhood experiences (ACEs) have detrimental health effects later in life. Our objective was to assess the association between ACEs and falls among middle-aged and older adults in the United States.

Methods: We used data from 38 437 participants aged 45 to 80 years from the 2023 Behavioral Risk Factor Surveillance System. The outcome was falling during the past 12 months. Adverse childhood experiences included questions about events before age 18, and 2 main domains of abuse (5 questions) and household dysfunction (6 questions), with a total score of 0 to 11, dichotomized as ≥2 ACEs versus 0-1. We assessed the association between ACEs and falling and explored whether risk factors for falling mediate the association between ACEs and falling.

Results: Among middle-aged adults (45-64 years), 22.3% had fallen, and 46.4% had ≥2 ACEs. Among older adults (≥65), 27.7% had fallen, and 31.7% had ≥2 ACEs. In multivariate analyses, participants with ≥2 ACEs have increased odds of falling compared to those with 0-1 ACEs among middle-aged (odds ratio [OR] = 1.34) and older adult participants (OR = 1.28). Even one individual ACE question, such as living with anyone who served in prison (among 45-64; OR = 1.43) or being sexually touched (among ≥65; OR = 1.45), has an independent association with falling. People with depression, functional difficulties, multimorbidity, and difficulty remembering exhibited higher proportions (%) for mediation.

Conclusions: Adverse childhood experiences are an additional risk factor for falling among middle-aged and older adults in the United States. Clinicians and public health practitioners should also consider ACEs when exploring determinants for falling across the life course.

Background: Social isolation is a key social determinant of health, yet research on its relationship with functional impairment is limited. We compared functional impairment score trajectories of older adults who experienced social isolation versus those who did not, using 2 different statistical approaches to handle attrition due to dropout and death.

Methods: Data were from 2 Northern California observational cohorts of people aged 50+ (n = 2476): Kaiser Healthy Aging and Different Life Experiences (KHANDLE) and Study of Healthy Aging in African Americans (STAR). We fit linear mixed effects models for functional impairment scores (sum of 12 items measuring basic activities of daily living [ADLs], instrumental ADLs, and mobility; range: 0-36) by baseline social isolation status (yes/no; 3-5 positive answers on 5 social contact items), adjusted for age and sex/gender. We estimated average marginal wave-specific differences in functional impairment scores, comparing approaches to address attrition.

Results: At baseline, 30% of participants reported social isolation; the median functional impairment score was 2 (Q1, Q3 = 0, 5). Baseline functional impairment scores were 1.03 points (95% CI, 0.84-1.20) higher among participants experiencing social isolation versus not. At wave 4, this difference decreased to 0.80 (95% CI, 0.52-1.07) among those remaining in the study and increased to 1.16 (95% CI, 0.83-1.42) assuming attrition was eliminated. Dropout and death were higher among participants experiencing social isolation.

Conclusion: In a diverse cohort of older adults, those experiencing social isolation tend to experience greater functional impairment, but differences in trajectories depend on how attrition is handled.

Background: While associations between poor oral health and cognitive impairment are documented, research on how different oral health conditions relate to specific cognitive measures remains limited.

Methods: Using data from 756 Baltimore Longitudinal Study of Aging 2005-2024 participants (mean age = 72.0 years, 52.5% women, 24.2% Black), we investigated the association between the first oral health assessment and subsequent cognitive decline across domains in older adults aged 60+ who were free of cognitive impairment at baseline over an average of 7.7 follow-up. Cognitive function was assessed across language, executive function, attention, memory, and visuospatial ability domains, with domain-specific composite scores calculated using various cognitive tests. Oral health was evaluated for clinically-assessed tooth loss and dental plaque, alongside self-reported periodontal symptoms. Linear mixed-effect models were used to examine the longitudinal associations with cognitive decline, adjusted for socio-demographic and clinical characteristics.

Results: After covariates adjustment, more tooth loss was associated with greater declines across all cognitive domains, including language (β = -0.0017; 95% CI = -0.0025, -0.0008), executive function (β = -0.0011; 95% CI = -0.0019, -0.0002), attention (β = -0.0011; 95% CI = -0.0021, -0.0001), memory (β = -0.0018; 95% CI = -0.0030, -0.0005), and visuospatial ability (β = -0.0017; 95% CI = -0.0029, -0.0006). Dental plaque was associated with executive function (β = -0.0165; 95% CI = -0.0276, -0.0054) and memory (β = -0.0279; 95% CI = -0.0444, -0.0115) declines. Presence of periodontal symptoms was only associated with executive function decline (β = -0.0004; 95% CI = -0.0007, -0.0001).

Conclusions: Tooth loss may indicate broader cognitive decline, while other oral health conditions, such as plaque and periodontal symptoms, particularly affect memory or executive function. Future studies are warranted to investigate underlying mechanisms.

Background: Serum uric acid (SUA) has been linked to cognitive function, but sex-specific associations remain unclear. Biological differences in SUA levels between sexes, driven by hormonal and renal factors, highlight the importance of sex-stratified analysis. This study examined the association between SUA levels and changes in cognitive function in older adults.

Methods: A total of 11 411 community-dwelling ASPirin in Reducing Events in the Elderly participants, free from dementia at baseline and with valid SUA measurements, were included. The Modified Mini-Mental State Examination (3MS), Hopkins Verbal Learning Test-Revised (HVLT-R), Symbol Digit Modalities Test, and Controlled Oral Word Association Test were used to assess cognition at baseline and over a median follow-up of 9 years. Separate linear mixed-effects regression models in males and females were fitted to assess the associations between SUA levels and change in cognitive function over time.

Results: Females in the lowest SUA quintile (Q1) had significant declines in the measure of global cognition (3MS: β ±SE= -0.07 ± 0.03, p = .02) and episodic memory (HVLT-R; delayed recall: β±SE= -0.03 ± 0.01, p = .02) compared to the middle quintiles (Q2-Q4), but the highest SUA quintile (Q5) was not associated with decline. No associations were observed for executive function, verbal fluency, or psychomotor speed. In males, no significant associations between SUA levels and change in cognitive function were observed.

Conclusion: Low SUA levels were linked to decline in the measure of global cognition and episodic memory among females but not males. High SUA levels were not associated with cognitive decline. Managing SUA levels within the physiological range may support cognitive health, particularly in older females.