Suchergebnisse

Abstract
Aging is characterized by a progressive loss of cellular functions that increase the risk of developing chronic diseases, vascular dysfunction, and neurodegenerative conditions. The field of geroscience has identified cellular and molecular hallmarks of aging that may serve as targets for future interventions to reduce the risk of age-related disease and disability. These hallmarks include genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. Several studies show that exercise may favorably affect these processes and thereby have antiaging properties. The primary mechanisms through which exercise confers protective benefits in the brain are still incompletely understood. To better understand these effects and leverage them to help promote brain health, we present current findings supporting the notion that adaptive responses to exercise play a pivotal role in mitigating the hallmarks of aging and their effects on the aging cerebrovasculature, and ultimately contribute to the maintenance of brain function across the healthspan.

Abstract

Background
Circulating levels of n-3 polyunsaturated fatty acids (PUFAs) have been associated with frailty among Koreans (a population with a high intake of fish), but whether this association exists in Western populations with low fish intake is unknown. The present study examined the hypothesis that the prevalence of frailty was inversely associated with plasma levels of n-3 PUFAs, with the intake of oily fish, and with fish oil supplementation in older adults in the United Kingdom.


Methods
UK Biobank including 79 330 adults aged ≥65 years with dietary data, and 18 802 participants with plasma fatty acid data were used. Frailty was defined using the Cardiovascular Health Study index, plasma levels of n-3 PUFAs were measured by nuclear magnetic resonance, and intake of oily fish and/or fish oil supplements was collected via food frequency questionnaire.


Results
Frailty prevalence was inversely associated with n-3 PUFA levels [odds ratios (OR) per SD: 0.86, 95% confidence interval (CI) 0.79–0.94; p < .001], with oily fish intake (never vs ≥2 servings per week; OR 0.59, 95% CI 0.52–0.68, p < .001), and with the use of fish oil supplements (OR 0.72; 95% CI 0.66–0.78; p < .001) after adjusting for confounding factors. All 3 exposures were also associated with each frailty criterion, particularly low physical activity and walking pace.


Conclusions
Inverse associations between plasma n-3 PUFA levels and measures of frailty suggest that higher intakes of oily fish or the use of fish oil supplements may help prevent frailty in older adults in the United Kingdom.

Abstract

Background
The relationship of claims-based frailty index (CFI), a validated measure to identify frail individuals using Medicare data, and frailty measures used in clinical practice has not yet been fully explored.


Methods
We identified community-dwelling participants of the 2015 National Health and Aging Trends Study (NHATS) whose CFI scores could be calculated using linked Medicare claims. We calculated 9 commonly used clinical frailty measures from their NHATS in-person examination: Study of Osteoporotic Fracture Index (SOF), FRAIL Scale, Frailty Phenotype, Clinical Frailty Scale (CFS), Vulnerable Elder Survey-13 (VES-13), Tilburg Frailty Indicator (TFI), Groningen Frailty Indicator (GFI), Edmonton Frail Scale (EFS), and 40-item Frailty Index (FI). Using equipercentile method, CFI scores were linked to clinical frailty measures. C-statistics and test characteristics of CFI to identify frailty as defined by each clinical frailty measure were calculated.


Results
Of the 3 963 older adults, 44.5% were ≥75 years, 59.4% were female, and 82.3% were non-Hispanic White. A CFI of 0.25 was equipercentile to the following clinical frailty measure scores: SOF 1.4, FRAIL 1.8, Phenotype 1.8, CFS 5.4, VES-13 5.7, TFI 4.6, GFI 5.0, EFS 6.0, and FI 0.26. The C-statistics of using CFI to identify frailty as defined by each clinical measure were ≥0.70, except for CFS and VES-13. The optimal CFI cutpoints to identify frailty per clinical frailty measure ranged from 0.212 to 0.242, with sensitivity and specificity of 0.37–0.83 and 0.66–0.84, respectively.


Conclusions
Understanding the relationship of CFI and commonly used clinical frailty measures can enhance the interpretability and potential utility of CFI.

Abstract

Background
Age is the greatest risk factor for lower urinary tract symptoms attributed to benign prostatic hyperplasia (LUTS/BPH). Although LUTS/BPH can be managed with pharmacotherapy, treatment failure has been putatively attributed to numerous pathological features of BPH (eg, prostatic fibrosis, inflammation). Mitochondrial dysfunction is a hallmark of aging; however, its impact on the pathological features of BPH remains unknown.


Methods
Publicly available gene array data were analyzed. Immunohistochemistry examined mitochondrial proteins in the human prostate. The effect of complex I inhibition (rotenone) on a prostatic cell line was examined using quantitative polymerase chain reaction, immunocytochemistry, and Seahorse assays. Oleic acid (OA) was tested as a bypass of complex I inhibition. Aged mice were treated with OA to examine its effects on urinary dysfunction. Voiding was assessed longitudinally, and a critical complex I protein measured.


Results
Mitochondrial function and fibrosis genes were altered in BPH. Essential mitochondrial proteins (ie, voltage-dependent anion channels 1 and 2, PTEN-induced kinase 1, and NADH dehydrogenase [ubiquinone] iron–sulfur protein 3, mitochondrial [NDUFS3]) were significantly (p < .05) decreased in BPH. Complex I inhibition in cultured cells resulted in decreased respiration, altered NDUFS3 expression, increased collagen deposition, and gene expression. OA ameliorated these effects. OA-treated aged mice had significantly (p < .05) improved voiding function and higher prostatic NDUFS3 expression.


Conclusions
Complex I dysfunction is a potential contributor to fibrosis and lower urinary tract dysfunction in aged mice. OA partially bypasses complex I inhibition and therefore should be further investigated as a mitochondrial modulator for treatment of LUTS/BPH. Hypotheses generated in this investigation offer a heretofore unexplored cellular target of interest for the management of LUTS/BPH.

Abstract

Background
The rapidly growing field of multimorbidity research demonstrates that changes in multimorbidity in mid- and late-life have far reaching effects on important person-centered outcomes, such as health-related quality of life. However, there are few organizing frameworks and comparatively little work weighing the merits and limitations of various quantitative methods applied to the longitudinal study of multimorbidity.


Methods
We identify and discuss methods aligned to specific research objectives with the goals of (i) establishing a common language for assessing longitudinal changes in multimorbidity, (ii) illuminating gaps in our knowledge regarding multimorbidity progression and critical periods of change, and (iii) informing research to identify groups that experience different rates and divergent etiological pathways of disease progression linked to deterioration in important health-related outcomes.


Results
We review practical issues in the measurement of multimorbidity, longitudinal analysis of health-related data, operationalizing change over time, and discuss methods that align with 4 general typologies for research objectives in the longitudinal study of multimorbidity: (i) examine individual change in multimorbidity, (ii) identify subgroups that follow similar trajectories of multimorbidity progression, (iii) understand when, how, and why individuals or groups shift to more advanced stages of multimorbidity, and (iv) examine the coprogression of multimorbidity with key health domains.


Conclusions
This work encourages a systematic approach to the quantitative study of change in multimorbidity and provides a valuable resource for researchers working to measure and minimize the deleterious effects of multimorbidity on aging populations.

Abstract

Background
To examine the association between cumulative cognitive function and subsequent mortality among patients hospitalized for acute heart failure (AHF).


Methods
Based on a prospective cohort of patients hospitalized for AHF, cognitive function was measured using Mini-Cog test at admission, 1- and 12-month following discharge. Cumulative cognitive function was interpreted by cumulative Mini-Cog score and cumulative times of cognitive impairment. Outcomes included subsequent all-cause and cardiovascular mortality.


Results
1 454 patients hospitalized for AHF with median follow-up of 4.76 (interquartile range [IQR]: 4.18–5.07) years were included. Tertile 1 of cumulative Mini-Cog score had the highest risk of all-cause (hazard ratio [HR]: 1.52, 95% confidence interval [CI]: 1.14–2.03) and cardiovascular mortality (HR: 1.40, 95% CI: 1.02–1.93) compared with Tertile 3; patients with ≥2 times of cognitive impairment had the highest risk of all-cause (HR: 1.34, 95% CI: 1.03–1.73) and cardiovascular mortality (HR: 1.25, 95% CI: 0.93–1.67) compared with patients without any cognitive impairment. Cumulative Mini-Cog score provided the highest incremental prognostic ability in predicting all-cause (C-statistics: 0.64, 95% CI: 0.61–0.66) and cardiovascular mortality (C-statistics: 0.63, 95% CI: 0.60–0.67) risk on the basis of Get With The Guidelines-Heart Failure score.


Conclusions
Poor cumulative cognitive function was associated with increased risk of subsequent mortality and provided incremental prognostic ability for the outcomes among patients with AHF. Longitudinal assessment and monitoring of cognitive function among patients with AHF would be of great importance in identifying patients at greater risk of self-care absence for optimizing personal disease management in clinical practice.

Abstract

Background
Lower urinary tract symptoms (LUTS) in older men are associated with an increased risk of mobility limitations. Lower extremity muscle quality may represent a novel shared mechanism of both LUTS and mobility limitations.


Methods
We evaluated associations of thigh skeletal muscle measures (strength, area, and specific force) with total LUTS severity (American Urologic Association Symptom Index; AUASI) and voiding and storage subscores among 352 men aged ≥60 years enrolled in the Baltimore Longitudinal Study of Aging. Thigh muscle strength (Nm) was defined as maximum concentric 30°/s knee extensor torque, area (cm2), and specific force (Nm/cm2) defined as strength/area. Associations with AUASI score were estimated using multivariable linear regression and linear mixed models.


Results
Mean thigh muscle strength at baseline was 139.7Nm. In cross-sectional multivariable models, each 39Nm increment in thigh muscle strength and 0.28Nm/cm2 increment in specific force was associated with −1.17 point (95% CI: −1.93 to −.41) and −0.95 point (95% CI: −1.63 to −0.27) lower AUASI score, respectively. Similar associations were observed for voiding and storage subscores, although somewhat attenuated. In longitudinal analyses, baseline muscle measures were not associated with annual change in AUASI, and current changes in muscle measures and AUASI were unrelated.


Conclusions
Cross-sectionally, higher thigh muscle strength and specific force were associated with decreased LUTS severity in older men. However, we did not observe concurrent worsening LUTS severity with declining thigh muscle strength, area, or specific force in longitudinal analyses.

Abstract

Background
Daily physical activity patterns differ by Alzheimer's disease (AD) status and might signal cognitive risk. It is critical to understand whether patterns are disrupted early in the AD pathological process. Yet, whether established AD risk markers (β-amyloid [Aβ] or apolipoprotein E-ε4 [APOE-ε4]) are associated with differences in objectively measured activity patterns among cognitively unimpaired older adults is unclear.


Methods
Wrist accelerometry, brain Aβ (+/−), and APOE-ε4 genotype were collected in 106 (Aβ) and 472 (APOE-ε4) participants (mean age 76 [standard deviation{SD}: 8.5) or 75 [SD: 9.2] years, 60% or 58% women) in the Baltimore Longitudinal Study of Aging. Adjusted linear and function-on-scalar regression models examined whether Aβ or APOE-ε4 status was cross-sectionally associated with activity patterns (amount, variability, or fragmentation) overall and by time of day, respectively. Differences in activity patterns by combinations of Aβ and APOE-ε4 status were descriptively examined (n = 105).


Results
There were no differences in any activity pattern by Aβ or APOE-ε4 status overall. Aβ+ was associated with lower total amount and lower within-day variability of physical activity overnight and early evening, and APOE-ε4 carriers had higher total amount of activity in the evening and lower within-day variability of activity in the morning. Diurnal curves of activity were blunted among those with Aβ+ regardless of APOE-ε4 status, but only when including older adults with mild cognitive impairment/dementia.


Conclusions
Aβ+ in cognitively unimpaired older adults might manifest as lower amount and variability of daily physical activity, particularly during overnight/evening hours. Future research is needed to examine changes in activity patterns in larger samples and by other AD biomarkers.

Abstract

Background
Mechanistic factors on the pathway to improving independent ambulatory ability among hip fracture patients by a multicomponent home-based physical therapy intervention that emphasized aerobic, strength, balance, and functional training are unknown. The aim of this study was to determine the effects of 2 different home-based physical therapy programs on muscle area and attenuation (reflects muscle density) of the lower extremities, bone mineral density (BMD), and aerobic capacity.


Methods
Randomized controlled trial of home-based 16 weeks of strength, endurance, balance, and function exercises (PUSH, n = 19) compared to seated active range-of-motion exercises and transcutaneous electrical neurostimulation (PULSE, n = 18) in community-dwelling adults >60 years of age within 26 weeks of hip fracture.


Results
In PUSH and PULSE groups combined, the fractured leg had lower muscle area and muscle attenuation and higher subcutaneous fat than the nonfractured leg (p < .001) at baseline. At 16 weeks, mean muscle area of the fractured leg was higher in the PUSH than PULSE group (p = .04). Changes in muscle area were not significantly different when compared to the comparative PULSE group. There was a clinically relevant difference in change in femoral neck BMD between groups (p = .05) that showed an increase after PULSE and decrease after PUSH. There were generally no between-group differences in mean VO2peak tests at 16-week follow-up, except the PUSH group reached a higher max incline (p = .04).


Conclusions
The treatment effects of a multicomponent home-based physical therapy intervention on muscle composition, BMD, and aerobic capacity were not significantly different than an active control intervention in older adults recovering from hip fracture.


Trial Registration
ClinicalTrials.gov Identifier: NCT01783704

Abstract

Background
Dysfunction in blood vessel dynamics may contribute to changes in muscle measures. Therefore, we examined associations of vascular health measures with grip strength and gait speed in adults from the Framingham Heart Study.


Methods
The cross-sectional study (1998–2001) included participants with 1 measure of grip strength (kg, dynamometer) or gait speed (4-m walk, m/s) and at least 1 measure of aortic stiffness (carotid–femoral pulse wave velocity, brachial pulse pressure, and brachial flow pulsatility index) or brachial artery structure and function (resting flow velocity, resting brachial artery diameter, flow-mediated dilation %, hyperemic brachial blood flow velocity, and mean arterial pressure [MAP]) assessed by tonometry and brachial artery ultrasound. The longitudinal study included participants with ≥1 follow-up measurement of gait speed or grip strength. Multivariable linear regression estimated the association of 1 standard deviation (SD) higher level of each vascular measure with annualized percent change in grip strength and gait speed, adjusting for covariates.


Results
In cross-sectional analyses (n = 2 498, age 61 ± 10 years; 56% women), higher resting brachial artery diameter (β ± standard error [SE] per 1 SD: 0.59 ± 0.24, p = .01) and MAP (β ± SE: 0.39 ± 0.17, p = .02) were associated with higher grip strength. Higher brachial pulse pressure (β ± SE: −0.02 ± 0.01, p = .07) was marginally associated with slower gait speed. In longitudinal analyses (n = 2 157), higher brachial pulse pressure (β ± SE: −0.19 ± 0.07, p = .005), was associated with slowing of gait speed but not with grip strength.


Conclusions
Higher brachial artery pulse pressure (measure of aortic stiffness) was associated with loss of physical function over ~11 years, although we found no evidence that microvascular function contributed to the relation.

Abstract

Background
The geroscience hypothesis posits that aging biological processes contribute to many age-related deficits, including the accumulation of multiple chronic diseases. Though only one facet of mitochondrial function, declines in muscle mitochondrial bioenergetic capacities may contribute to this increased susceptibility to multimorbidity.


Methods
The Study of Muscle, Mobility and Aging (SOMMA) assessed ex vivo muscle mitochondrial energetics in 764 older adults (mean age = 76.4, 56.5% women, and 85.9% non-Hispanic White) by high-resolution respirometry of permeabilized muscle fibers. We estimated the proportional odds ratio (POR [95% CI]) for the likelihood of greater multimorbidity (4 levels: 0 conditions, N = 332; 1 condition, N = 299; 2 conditions, N = 98; or 3+ conditions, N = 35) from an index of 11 conditions, per SD decrement in muscle mitochondrial energetic parameters. Distribution of conditions allowed for testing the associations of maximal muscle energetics with some individual conditions.


Results
Lower oxidative phosphorylation supported by fatty acids and/or complex I- and II-linked carbohydrates (eg, Max OXPHOSCI+CII) was associated with a greater multimorbidity index score (POR = 1.32 [1.13, 1.54]) and separately with diabetes mellitus (OR = 1.62 [1.26, 2.09]), depressive symptoms (OR = 1.45 [1.04, 2.00]) and possibly chronic kidney disease (OR = 1.57 [0.98, 2.52]) but not significantly with other conditions (eg, cardiac arrhythmia, chronic obstructive pulmonary disease).


Conclusions
Lower muscle mitochondrial bioenergetic capacities were associated with a worse composite multimorbidity index score. Our results suggest that decrements in muscle mitochondrial energetics may contribute to a greater global burden of disease and are more strongly related to some conditions than others.