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

Background: Antimicrobial peptides (AMPs) are key effectors of urinary tract innate immunity. Identifying differences in urinary AMP levels between younger and older adults is important in understanding older adults' susceptibility and response to urinary tract infections (UTI) and AMP use as diagnostic biomarkers. We hypothesized that uninfected older adults have higher urinary human neutrophil peptides 1-3 (HNP 1-3), human alpha-defensin-5 (HD-5), and human beta-defensin-2 (hBD-2), but lower urinary cathelicidin (LL-37) than younger adults.

Methods: We conducted a cross-sectional study of patients aged ≥18 years completing a family medicine clinic nonacute visit. Enzyme-linked immunosorbent assays were performed for AMPs. We identified associations between age and AMPs using unadjusted and multivariable linear regression models.

Results: Of the 308 subjects, 144 (46.8%) were ≥65 years of age. Comparing age ≥65 versus < 65 years, there were no significant differences in HNP 1-3 (p = .371), HD5 (p = .834), or LL-37 (p = .348) levels. Values for hBD-2 were lower in older adults versus younger (p < .001). In multivariable analyses, older males and females had significantly lower hBD-2 levels (p < .001 and p = .004). Models also showed urine leukocyte esterase was associated with increased levels of HNP 1-3 and HD5; hematuria with increased hBD-2; and urine cultures with contamination with increased HNP 1-3 and hBD-2.

Conclusions: Baseline urinary HNP 1-3, HD-5, and LL-37 did not vary with age. Older adults had lower baseline hBD-2. This finding has implications for the potential use of urinary AMPs as diagnostic markers and will facilitate further investigation into the role of innate immunity in UTI susceptibility in older adults.

Background: Lower urinary tract symptoms (LUTS) and mobility limitations are bidirectionally associated among older adults, but the role of skeletal muscle remains unknown. We evaluated cross-sectional associations of muscle health and physical performance with LUTS.

Methods: We used data from 377 women and 264 men aged >70 years in the Study of Muscle, Mobility and Aging (SOMMA). LUTS and urinary bother were assessed using the LURN Symptom Index-10 (SI-10; higher = worse symptoms). Muscle mass and volume were assessed using D3-creatine dilution (D3Cr) and magnetic resonance imaging. Grip strength and peak leg power assessed upper/lower extremity physical performance. 400-m walk, Short Physical Performance Battery (SPPB), and Four Square Step Test (FSST) assessed global physical performance. Mobility Assessment Tool-short form (MAT-sf) assessed self-reported mobility. We calculated Spearman correlation coefficients adjusted for age, body mass index, multimorbidity, and polypharmacy, chi-square tests, and Fisher's Z-test to compare correlations.

Results: Among women, LURN SI-10 total scores were inversely correlated with FSST (rs = 0.11, p = .045), grip strength (rs = -0.15, p = .006), and MAT-sf (rs = -0.18, p = .001), but not other muscle and physical performance measures in multivariable models. LURN SI-10 was not associated with any of these measures among men. Forty-four percent of women in the lowest tertile of 400-m walk speed versus 24% in the highest tertile reported they were at least "somewhat bothered" by urinary symptoms (p < .001), whereas differences among men were not significant.

Conclusions: Balance and grip strength were associated with LUTS severity in older women but not men. Associations with other muscle and physical performance measures varied by LUTS subtype but remained strongest among women.

Background: A goal of gerontology is to discover phenotypes that reflect biological aging distinct from disease pathogenesis. Biomarkers that are strongly associated with mortality could be used to define such a phenotype. However, the relation of such an index with multiple chronic conditions warrants further exploration.

Methods: A biomarker index (BI) was constructed in the Cardiovascular Health Study (N = 3 197), with a mean age of 74 years. The BI incorporated circulating levels of new biomarkers, including insulin-like growth factor-1, interleukin-6, amino-terminal pro-B-type natriuretic peptide, cystatin-C, C-reactive protein, tumor necrosis factor-alpha soluble receptor 1, fasting insulin, and fasting glucose, and was built based on their relationships with mortality. Cox proportional hazards models predicting a composite of death and chronic disease involving cardiovascular disease, dementia, and cancer were calculated with 6 years of follow-up.

Results: The hazard ratio (HR, 95% CI) for the composite outcome of death or chronic disease per category of BI was 1.65 (1.52, 1.80) and 1.75 (1.58, 1.94) in women and men, respectively. The HR (95% CI) per 5 years of age was 1.57 (1.48, 1.67) and 1.55 (1.44, 1.67) in women and men, respectively. Moreover, BI could attenuate the effect of age on the composite outcome by 16.7% and 22.0% in women and men, respectively.

Conclusions: Biomarker index was significantly and independently associated with a composite outcome of death and chronic disease, and attenuated the effect of age. The BI that is composed of plasma biomarkers may be a practical intermediate phenotype for interventions aiming to modify the course of aging.

Background: Physical function and its decline in older age may be connected to treatable vascular risk factors in mid-life. This study aimed to evaluate whether these factors affect the underlying rate of decline.

Methods: This prospective cohort included 5 481 older adults aged 67-91 in the Atherosclerosis Risk in Communities Study (mean [standard deviation {SD}] age = 75.8 [5.0], 58% women, 21% Black race) without a history of stroke. The main outcome was the rate of Short Physical Performance Battery (SPPB) decline over a median late-life follow-up of 4.8 years. Primary mid-life (aged 45-64) exposures were Visit 1 hypertension (>140/90 mm Hg or treatment), diabetes (>126 mg/dL or treatment), high cholesterol (>240 mg/dL or treatment), and smoking, and number of decades of vascular risk exposure across Visits 1-4.

Results: The average adjusted rate of SPPB decline (points per 5 years) for older adults was -0.79 (confidence interval [CI]: -0.87, 0.71) and was accelerated by mid-life hypertension (+57% decline vs normotension: additional decline of -0.47, 95% CI: -0.64, -0.30), diabetes (+73% decline vs no diabetes: additional decline of -0.67, 95% CI: -1.09, -0.24), elevated systolic blood pressure (+17% decline per SD: -0.16, 95% CI: -0.23, -0.10), and elevated fasting blood glucose (+16% decline per SD: -0.015, 95% CI: -0.24, -0.06). Each decade greater mid-life exposure to hypertension (+32% decline: -0.93, 95% CI: -1.25, -0.61) and diabetes (+35% decline: -1.03, 95% CI: -1.68, -0.38) was associated with faster SPPB decline.

Conclusions: Mid-life control of blood pressure and diabetes may offset aging-related functional decline.

Background: Life-space mobility, which measures the distance, frequency, and independence achieved as individuals move through their community, is one of the most important contributors to healthy aging. The University of Alabama at Birmingham Life-Space Assessment (LSA) is the most commonly used measure of life-space mobility in older adults, yet U.S. national norms for LSA have not previously been reported. This study reports such norms based on age and sex among community-dwelling older adults.

Methods: A cross-sectional analysis using data from the national REasons for Geographic and Racial Disparities in Stroke cohort study. LSA data were available for 10 118 Black and White participants over age 50, which were grouped by age (in 5-year increments) and sex, weighted for the U.S. national population. Correlations were calculated between LSA and measures of functional and cognitive impairment and physical performance.

Results: The weighted mean LSA ranged from 102.9 for 50-54-year-old males to 69.5 for males aged 85 and older, and from 102.1 for 50-54-year-old females to 60.1 for females aged 85 and older. LSA was strongly correlated with measures of timed walking, activities of daily living, cognition, depressive symptoms, and quality of life (all p < .001).

Conclusions: We report U.S. national norms for LSA among community-dwelling Black and White older adults. These norms can serve as a reference tool for determining if clinical and research samples have greater or lesser life-space mobility than typical older adults in the United States for their age and sex.

Background: Subjective cognitive decline (SCD) has gained recent interest as a potential harbinger of neurodegenerative diseases such as Alzheimer's disease (AD) and cerebrovascular disease (CVD). In addition, SCD can be related to depressive symptomatology. However, the association between AD and CVD biomarkers, depressive symptomatology, and SCD is still unclear. We investigated the association of AD and CVD biomarkers and depressive symptomatology with SCD in individuals with subjective memory complaints (SCD-memory group) and individuals with subjective concentration complaints (SCD-concentration group).

Methods: We recruited a population-based cohort of 217 individuals (all aged 70 years, 53% female participants, 119 SCD-memory individuals, 23 SCD-concentration individuals, and 89 controls). AD and CVD were assessed through cerebrospinal fluid levels of the Aβ42/40 ratio and phosphorylated tau, and white matter signal abnormalities on magnetic resonance imaging, respectively. Associations between biomarkers, depressive symptomatology, and SCD were tested via logistic regression and correlation analyses.

Results: We found a significant association between depressive symptomatology with SCD-memory and SCD-concentration. Depressive symptomatology was not associated with AD and CVD biomarkers. Both the phosphorylated tau biomarker and depressive symptomatology predicted SCD-memory, and the Aβ42/40 ratio and depressive symptomatology predicted SCD-concentration.

Conclusions: The role of depressive symptomatology in SCD may differ depending on the stage within the spectrum of preclinical AD (as determined by amyloid-beta and tau positivity), and does not seem to reflect AD pathology. Our findings contribute to the emerging field of subclinical depressive symptomatology in SCD and clarify the association of different types of subjective complaints with distinct syndromic and biomarker profiles.

Background: Neighborhood deprivation and depression have been linked to epigenetic age acceleration. The next-generation epigenetic clocks including the DNA methylation (DNAm) GrimAge, and PhenoAge have incorporated clinical biomarkers of physiological dysregulation by selecting cytosine-phosphate-guanine sites that are associated with risk factors for disease, and have shown improved accuracy in predicting morbidity and time-to-mortality compared to the first-generation clocks. The aim of this study is to examine the association between neighborhood deprivation and DNAm GrimAge and PhenoAge acceleration in adults, and assess interaction with depressive symptoms.

Methods: The Canadian Longitudinal Study on Aging recruited 51 338 participants aged 45-85 years across provinces in Canada. This cross-sectional analysis is based on a subsample of 1 445 participants at baseline (2011-2015) for whom epigenetic data were available. Epigenetic age acceleration (years) was assessed using the DNAm GrimAge and PhenoAge, and measured as residuals from regression of the biological age on chronological age.

Results: A greater neighborhood material and/or social deprivation compared to lower deprivation (b = 0.66; 95% confidence interval [CI] = 0.21, 1.12) and depressive symptoms scores (b = 0.07; 95% CI = 0.01, 0.13) were associated with higher DNAm GrimAge acceleration. The regression estimates for these associations were higher but not statistically significant when epigenetic age acceleration was estimated using DNAm PhenoAge. There was no evidence of a statistical interaction between neighborhood deprivation and depressive symptoms.

Conclusions: Depressive symptoms and neighborhood deprivation are independently associated with premature biological aging. Policies that improve neighborhood environments and address depression in older age may contribute to healthy aging among older adults living in predominantly urban areas.

Background: Peripheral artery disease (PAD) is associated with lower physical activity but less is known about its association with daily patterns of activity. We examined the cross-sectional association between ankle-brachial index (ABI) and objectively measured patterns of physical activity among Hispanic/Latino adults.

Methods: We analyzed data from 7 688 participants (aged 45-74 years) in the Hispanic Community Health Study/Study of Latinos. ABI was categorized as low (≤0.90, indicating PAD), borderline low (0.91-0.99), normal (1.00-1.40), and high (>1.40, indicating incompressible ankle arteries). Daily physical activity metrics derived from accelerometer data included: log of total activity counts (LTAC), total log-transformed activity counts (TLAC), and active-to-sedentary transition probability (ASTP). Average differences between ABI categories in physical activity, overall and by 4-hour time-of-day intervals, were assessed using linear regression and mixed-effects models, respectively.

Results: In Hispanic/Latino adults, 5.3% and 2.6% had low and high ABIs, respectively. After adjustment, having a low compared to a normal ABI was associated with lower volume (LTAC = -0.13, p < .01; TLAC = -74.4, p = .04) and more fragmented physical activity (ASTP = 1.22%, p < .01). Having a low ABI was linked with more fragmented physical activity after 12 pm (p < .01). Having a high ABI was associated with lower volumes of activity (TLAC = -132.0, p = .03).

Conclusions: Having a low or high ABI is associated with lower and more fragmented physical activity in Hispanic/Latino adults. In adults with low ABI, physical activity is more fragmented in the afternoon to evening. Longitudinal research is warranted to expand these findings to guide targeted interventions for PAD or incompressible ankle arteries.

Background: Hearing loss is linked to loneliness and social isolation, but evidence is typically based on self-reported hearing. This study quantifies the associations of objective and subjective hearing loss with loneliness and social network characteristics among older adults with untreated hearing loss.

Methods: This study uses baseline data (N = 933) from the Aging and Cognitive Health Evaluation in Elders (ACHIEVE) study. Hearing loss was quantified by the better ear, speech-frequency pure tone average (PTA), Quick Speech-in-Noise test, and hearing-related quality of life. Outcomes were validated measures of loneliness and social network characteristics. Associations were assessed by Poisson, negative binomial, and linear regression adjusted for demographic, health, and study design characteristics.

Results: Participants were mean of 76.8 (4.0) years, 54.0% female, and 87.6% White. Prevalence of loneliness was 38%. Worse PTA was associated with a 19% greater prevalence of moderate or greater loneliness (prevalence ration [PR]: 1.19.95% CI: 1.06, 1.33). Better speech-in-noise recognition was associated with greater social network characteristics (eg, larger social network size [IRR: 1.04, 95% CI: 1.00, 1.07]). Worse hearing-related quality of life was associated with a 29% greater prevalence of moderate or greater loneliness (PR: 1.29, 95% CI: 1.19, 1.39) and worse social network characteristics (eg, more constricted social network size [IRR: 0.96, 95% CI: 0.91, 1.00]).

Conclusions: Results suggest the importance of multiple dimensions of hearing to loneliness and social connectedness. Hearing-related quality of life may be a potentially useful, easily administered clinical tool for identifying older adults with hearing loss associated with greater loneliness and social isolation.

Background: The relationship between amino acids, B vitamins, and their metabolites with D3-creatine (D3Cr) dilution muscle mass, a more direct measure of skeletal muscle mass, has not been investigated. We aimed to assess associations of plasma metabolites with D3Cr muscle mass, as well as muscle strength and physical performance in older men from the Osteoporotic Fractures in Men cohort study.

Methods: Out of 1 425 men (84.2 ± 4.1 years), men with the lowest D3Cr muscle mass (n = 100), slowest walking speed (n = 100), lowest grip strength (n = 100), and a random sample (n = 200) serving as a comparison group to the low groups were included. Metabolites were analyzed using liquid chromatography-tandem mass spectrometry. Metabolite differences between the low groups and random sample and their relationships with the muscle outcomes adjusted for confounders and multiple comparisons were assessed using t-test/Mann-Whitney-Wilcoxon and partial correlations, respectively.

Results: For D3Cr muscle mass, significant biomarkers (p < .001) with ≥10% fold difference and largest partial correlations were tryptophan (Trp; r = 0.31), kynurenine (Kyn)/Trp; r = -0.27), nicotinamide (Nam)/quinolinic acid (Quin; r = 0.21), and alpha-hydroxy-5-methyl-tetrahydrofolate (hm-THF; r = -0.25). For walking speed, hm-THF, Nam/Quin, and Quin had the largest significance and fold difference, whereas valine (r = 0.17), Trp (r = 0.17), HKyn/Xant (r = -0.20), neopterin (r = -0.17), 5-methyl-THF (r = -0.20), methylated folate (r = -0.21), and thiamine (r = -0.18) had the strongest correlations. Only hm-THF was correlated with grip strength (r = -0.21) and differed between the low group and the random sample.

Conclusions: Future interventions focusing on how the Trp metabolic pathway or hm-THF influences D3Cr muscle mass and physical performance declines in older adults are warranted.