Publications (234)1568.46 Total impact
- [Show abstract] [Hide abstract] ABSTRACT: Background - Age is the foremost risk factor for atrial fibrillation (AF), and AF has a rising prevalence in older adults. How AF may contribute to decline in physical performance in older adults has had limited investigation. We examined the associations of incident AF and 4-year interval declines in physical performance at ages 70, 74, 78, and 82 years in the Health, Aging, and Body Composition (Health ABC) Study. Methods and Results - Health ABC is a prospective cohort of community-dwelling older adults (n=3075). The study conducted serial assessments of physical performance with the Health ABC physical performance battery (scored 0-4), grip strength, 2-minute walk distance, and 400-m walking time. Incident AF was identified from the Center for Medicare and Medicaid Services and related to 4-year interval decline in physical performance. After exclusions, the analysis included 2753 Health ABC participants (52% women, 41% black race). Participants with AF had a significantly greater 4-year physical performance battery decline than those without AF at age 70, 74, 78, and 82, with mean estimated decline ranging from -0.08 to -0.10 U (95% confidence interval, -0.18 to -0.01; P<0.05 for all estimates) after multivariable adjustment. Grip strength, walk distance, and walk time similarly showed significantly greater declines at each 4-year age interval in participants with AF. Conclusions - In community-based cohort older adults, incident AF was associated with increased risk of decline in physical performance. Further research is essential to identify mechanisms and preventive strategies for how AF may contribute toward declining physical performance in older adults.
- [Show abstract] [Hide abstract] ABSTRACT: Background: Age-related peripheral hearing impairment (HI) is prevalent, treatable, and may be a risk factor for dementia in older adults. In prospective analysis, we quantified the association of HI with incident dementia and with domain-specific cognitive decline in memory, perceptual speed, and processing speed. Methods: Data were from the Health, Aging and Body Composition (Health ABC) study, a biracial cohort of well-functioning adults aged 70-79 years. Dementia was defined using a prespecified algorithm incorporating medication use, hospital records, and neurocognitive test scores. A pure-tone average in decibels hearing level (dBHL) was calculated in the better hearing ear using thresholds from 0.5 to 4kHz, and HI was defined as normal hearing (≤25 dBHL), mild (26-40 dBHL), and moderate/severe (>40 dBHL). Associations between HI and incident dementia and between HI and cognitive change were modeled using Cox proportional hazards models and linear mixed models, respectively. Results: Three-hundred eighty seven (20%) participants had moderate/severe HI, and 716 (38%) had mild HI. After adjustment for demographic and cardiovascular factors, moderate/severe audiometric HI (vs. normal hearing) was associated with increased risk of incident dementia over 9 years (hazard ratio: 1.55, 95% confidence interval [CI]: 1.10, 2.19). Other than poorer baseline memory performance (difference of -0.24 SDs, 95% CI: -0.44, -0.04), no associations were observed between HI and rates of domain-specific cognitive change during 7 years of follow-up. Conclusions: HI is associated with increased risk of developing dementia in older adults. Randomized trials are needed to determine whether treatment of hearing loss could postpone dementia onset in older adults.
- [Show abstract] [Hide abstract] ABSTRACT: Background: Few cohort studies have examined longitudinal associations between age-related changes in cognition and physical performance. Further, whether these associations differ for men versus women or can be attributed to differences in physical activity (PA) is unknown. Methods: Participants were 2,876 initially well-functioning community-dwelling older adults (aged 70-79 years at baseline; 52% female; 39% black) studied over a 9-year period. Usual gait speed, self-reported PA, and two cognitive measures-Digit Symbol Substitution Test (DSST) and Mini-Modified Mental State examination (3MS)-were assessed years 0 (ie, baseline), 4, and 9. Results: Early decline between years 0 and 4 in gait speed predicted later decline between years 4 and 9 in performance on the 3MS (β = 0.10, p = .004) and on the DSST (β = 0.16, p < .001). In contrast, the associations between early decline in cognition and later decline in gait speed were weaker and were non-significant after correcting for multiple comparisons (β = 0.08, p = .019 for 3MS and β = .06, p = .051 for DSST). All associations were similar for women and men and were unaltered when accounting for PA levels. Conclusions: The results indicate declining gait speed as a precursor to declining cognitive functioning, and suggest a weaker reciprocal process among older women and men.
- [Show abstract] [Hide abstract] ABSTRACT: Importance Depression has been identified as a risk factor for dementia. However, most studies have measured depressive symptoms at only one time point, and older adults may show different patterns of depressive symptoms over time.Objective To investigate the association between trajectories of depressive symptoms and risk of dementia in older adults.Design, Setting, and Participants This was a prospective cohort investigation of black and white community-dwelling older adults in the Health, Aging, and Body Composition study. Participants were enrolled between May 1997 and June 1998 and followed up through 2001-2002. The dates of this analysis were September 2014 to December 2015. The setting was community research centers in Memphis, Tennessee, and Pittsburgh, Pennsylvania. Trajectories of depressive symptoms were assessed from baseline to year 5. Symptoms were measured with the Center for Epidemiologic Studies Depression Scale Short Form, and trajectories were calculated using latent class growth curve analysis.Main Outcomes and Measures Incident dementia through year 11, determined by dementia medication use, hospital records, or significant cognitive decline (≥1.5 SD race-specific decline on the Modified Mini-Mental State Examination). We examined the association between depressive symptom trajectories and dementia incidence using Cox proportional hazards regression models adjusted for demographics, health factors that differed between groups, and cognition during the depressive symptom assessment period (baseline to year 5).Results The analytic cohort included 2488 black and white older adults with repeated depressive symptom assessments from baseline to year 5 who were free of dementia throughout that period. Their mean (SD) age at baseline was 74.0 (2.8) years, and 53.1% (n = 1322) were female. The following 3 depressive symptom trajectories were identified: consistently minimal symptoms (62.0% [n = 1542] of participants), moderate and increasing symptoms (32.2% [n = 801] of participants), and high and increasing symptoms (5.8% [n = 145] of participants). Compared with the consistently minimal trajectory, having a high and increasing depressive symptom trajectory was associated with significantly increased risk of dementia (fully adjusted hazard ratio, 1.94; 95% CI, 1.30-2.90), while the moderate and increasing trajectory was not associated with risk of dementia after full adjustment. Sensitivity analyses indicated that the high and increasing trajectory was associated with dementia incidence, while depressive symptoms at individual time points were not.Conclusions and Relevance Older adults with a longitudinal pattern of high and increasing depressive symptoms are at high risk for dementia. Individuals’ trajectory of depressive symptoms may inform dementia risk more accurately than one-time assessment of depressive symptoms.
- [Show abstract] [Hide abstract] ABSTRACT: Objective: Previous studies demonstrate that the metabolic syndrome is associated with distal symmetric polyneuropathy (DSP). We aimed to determine the magnitude of this effect and the precise components involved. Research design and methods: We determined the symptomatic DSP prevalence in the Health, Aging, and Body Composition Study (prospective cohort study, with subjects aged 70-79 years at baseline), stratified by glycemic status (glucose tolerance test) and the number of additional metabolic syndrome components (updated National Cholesterol Education Program/Adult Treatment Panel III definition). DSP was defined as neuropathic symptoms (questionnaire) plus at least one of three confirmatory tests (heavy monofilament, peroneal conduction velocity, and vibration threshold). Multivariable logistic and linear regression evaluated the association of metabolic syndrome components with DSP in cross-sectional and longitudinal analyses. Results: Of 2,382 participants with neuropathy measures (mean age 73.5 ± 2.9 years, 38.2% black, 51.7% women), 21.0% had diabetes, 29.9% prediabetes, 52.8% metabolic syndrome, and 11.1% DSP. Stratified by glycemic status, DSP prevalence increased as the number of metabolic syndrome components increased (P = 0.03). Diabetes (cross-sectional model, odds ratio [OR] 1.65 [95% CI 1.18-2.31]) and baseline hemoglobin A1C (longitudinal model, OR 1.42 [95% CI 1.15-1.75]) were the only metabolic syndrome measures significantly associated with DSP. Waist circumference and HDL were significantly associated with multiple secondary neuropathy outcomes. Conclusions: Independent of glycemic status, symptomatic DSP is more common in those with additional metabolic syndrome components. However, the issue of which metabolic syndrome components drive this association, in addition to hyperglycemia, remains unclear. Larger waist circumference and low HDL may be associated with DSP, but larger studies with more precise metabolic measures are needed.
- [Show abstract] [Hide abstract] ABSTRACT: Study objectives: To examine the association between nocturia (walking up from sleep for urination) and mortality risk among community dwelling older men. Methods: This is a secondary data analysis using data obtained from the Health Aging Body Composition (Health ABC) Study. Frequency of nocturia was determined at baseline using a questionnaire. Results: A total of 1478 older men, mean (SD) age 73.8 (2.9) years, were included in the analysis. During a follow up period of 9.9 years, a total of 760 deaths were reported. Mortality rate was significantly higher for participants with 3 or more nocturia episodes per night, in comparison to those with 0-1 episodes (HR [CI] : 1.21 [1.00-1.47], p = 0.055), even after controlling for baseline characteristics which included demographic variables, body mass index, lower urinary tract symptoms, use of loop diuretics, insomnia symptoms, feeling excessively sleepy during the day/ daytime naps, sleep duration, and use of sleep medications. However, the association between ≥3 nocturia episodes per night and mortality risk was no longer statistically significant once prevalent diabetes mellitus and cardiovascular disease were included in the model (HR [CI]: 1.18 [0.97- 1.44], p = 0.100). Conclusions: Nocturia is associated with mortality independent of insomnia symptoms and sleep duration. The relationship is explained in part by prevalent cardiovascular disease and diabetes mellitus. The results underscore the impact of these medical conditions on the association between 3 or more nocturia episodes and increased mortality risk among older men.
- [Show abstract] [Hide abstract] ABSTRACT: Objective: The objective of the study is was investigate the association between hearing impairment and anxiety. Method: We conducted a cross-sectional analysis of 1,732 community-based adults aged 76 to 85 years who participated in the Health Aging and Body Composition (ABC) study. Logistic regression models were adjusted for demographic and cardiovascular risk factors. Hearing impairment was defined by the speech-frequency pure tone average. Anxiety was defined as reporting two symptoms of at least "a little" or one symptom "quite a bit" on the three-item Hopkins Symptom Checklist. Results: Compared with individuals with no hearing impairment, the odds of prevalent anxiety were higher among individuals with mild hearing impairment (odds ratio [OR] = 1.32, 95% confidence interval [CI] = [1.01, 1.73]) and moderate or greater hearing impairment (OR = 1.59, 95% CI = [1.14, 2.22]). Hearing aid use was not significantly associated with lower odds of anxiety. Discussion: Hearing impairment is independently associated with greater odds of anxiety symptoms in older adults.
- [Show abstract] [Hide abstract] ABSTRACT: Objectives: To better understand the potential impact of hearing impairment (HI) and hearing aid use on emotional vitality and mental health in older adults. Method: We investigated the cross-sectional association of HI with emotional vitality in 1,903 adults aged 76-85 years in the Health ABC study adjusted for demographic and cardiovascular risk factors. Hearing was defined by the speech frequency pure tone average (no impairment < 25 dB, mild impairment 25-40 dB, and moderate or greater impairment > 40 dB). Emotional vitality was defined as having a high sense of personal mastery, happiness, low depressive symptomatology, and low anxiety. Results: Compared with individuals with no HI, participants with moderate or greater HI had a 23% lower odds of emotional vitality (odds ratio [OR] = 0.77; 95% confidence interval [CI]: 0.59-0.99). Hearing aid use was not associated with better emotional vitality (OR = 0.98; 95% CI: 0.81-1.20). Discussion: HI is associated with lower odds of emotional vitality in older adults. Further studies are needed to examine the longitudinal impact of HI on mental health and well-being.
- [Show abstract] [Hide abstract] ABSTRACT: Background and objectives: Low serum bicarbonate associates with mortality in CKD. This study investigated the associations of bicarbonate and acid-base status with mortality in healthy older individuals. Design, setting, participants, & measurements: We analyzed data from the Health, Aging, and Body Composition Study, a prospective study of well functioning black and white adults ages 70-79 years old from 1997. Participants with arterialized venous blood gas measurements (n=2287) were grouped into <23.0 mEq/L (low), 23.0-27.9 mEq/L (reference group), and ≥28.0 mEq/L (high) bicarbonate categories and according to acid-base status. Survival data were collected through February of 2014. Mortality hazard ratios (HRs; 95% confidence intervals [95% CIs]) in the low and high bicarbonate groups compared with the reference group were determined using Cox models adjusted for demographics, eGFR, albuminuria, chronic obstructive pulmonary disease, smoking, and systemic pH. Similarly adjusted Cox models were performed according to acid-base status. Results: The mean age was 76 years, 51% were women, and 38% were black. Mean pH was 7.41, mean bicarbonate was 25.1 mEq/L, 11% had low bicarbonate, and 10% had high bicarbonate. Mean eGFR was 82.1 ml/min per 1.73 m(2), and 12% had CKD. Over a mean follow-up of 10.3 years, 1326 (58%) participants died. Compared with the reference group, the mortality HRs were 1.24 (95% CI, 1.02 to 1.49) in the low bicarbonate and 1.03 (95% CI, 0.84 to 1.26) in the high bicarbonate categories. Compared with the normal acid-base group, the mortality HRs were 1.17 (95% CI, 0.94 to 1.47) for metabolic acidosis, 1.21 (95% CI, 1.01 to 1.46) for respiratory alkalosis, and 1.35 (95% CI, 1.08 to 1.69) for metabolic alkalosis categories. Respiratory acidosis did not associate with mortality. Conclusions: In generally healthy older individuals, low serum bicarbonate associated with higher mortality independent of systemic pH and potential confounders. This association seemed to be present regardless of whether the cause of low bicarbonate was metabolic acidosis or respiratory alkalosis. Metabolic alkalosis also associated with higher mortality.
- [Show abstract] [Hide abstract] ABSTRACT: Background: White matter hyperintensities (WMH), a common marker of cerebral small vessel disease, and lower microstructural integrity of normal-appearing white matter are associated with slower gait. How these cerebral measures interact in relation to slower gait is unknown. We assessed whether microstructural integrity of normal-appearing white matter, measured by fractional anisotropy (FA), moderates the association of higher WMH with slower gait. Methods: WMH, FA, and gait speed were acquired for 265 community-dwelling older adults (average age = 82.9 years). Results: The inverse association between WMH and gait was robust to adjustment for age, gender, muscle strength, obesity, stroke, and hypertension (fully adjusted model: βs = -0.19, p = .001). The interaction between WMH and FA was significant; analyses stratified by FA showed that the inverse association between WMH and gait speed was significant only for those with low FA (FA < median, fully adjusted model: βs = -0.28, p = .001). Voxel-based results were similar for participants with FA less than median, there was an inverse association between gait speed and WMH which extended throughout the white matter (genu and body of corpus callosum, anterior limb of internal capsule, corona radiata, and superior longitudinal and fronto-occipital fasciculus). In contrast, for participants with FA ≥ median, the association was limited to the genu of corpus callosum, the cingulum, and the inferior longitudinal fasciculus. Conclusions: Microstructural integrity is a moderating factor in the association between WMH and gait. Future studies should examine whether higher microstructural integrity represents a source of compensation in those with greater WMH burden to maintain function in late life.
- [Show abstract] [Hide abstract] ABSTRACT: To compare the relative predictive power of handgrip and leg extension strength in predicting slow walking. Report of correlative analysis from two epidemiological cohort studies. Foundation of the National Institutes of Health Sarcopenia Project. Men and women aged 67 to 93 (N = 6,766). Leg strength, handgrip strength, and gait speed were measured. Strength cutpoints associated with slow gait speed were developed using classification and regression tree analyses and compared using ordinary least squares regression models. The cutpoints of lower extremity strength associated with slow gait speed were 154.6 N-m in men and 89.9 N-m in women for isometric leg extension strength and 94.5 N-m in men and 62.3 N-m in women for isokinetic leg extension strength. Weakness defined according to handgrip strength (odds ratios (OR) = 1.99 to 4.33, c-statistics = 0.53 to 0.67) or leg strength (ORs = 2.52 to 5.77; c-statistics = 0.61 to 0.66) was strongly related to odds of slow gait speed. Lower extremity strength contributed 1% to 16% of the variance and handgrip strength contributed 3% to 17% of the variance in the prediction of gait speed depending on sex and mode of strength assessment. Muscle weakness of the leg extensors and forearm flexors is related to slow gait speed. Leg extension strength is only a slightly better predictor of slow gait speed. Thus, handgrip and leg extension strength appear to be suitable for screening for muscle weakness in older adults.
- [Show abstract] [Hide abstract] ABSTRACT: Background: We investigated sera from elderly subjects with and without age-related macular degeneration (AMD) for presence of autoantibodies (AAbs) against human macular antigens and characterized their identity. Methods: Sera were collected from participants in the Age-Related Maculopathy Ancillary (ARMA) Study, a cross-sectional investigation ancillary to the Health ABC Study, enriched with participants from the general population. The resulting sample (mean age: 79.2±3.9 years old) included subjects with early to advanced AMD (n = 131) and controls (n = 231). Sera were tested by Western blots for immunoreactive bands against human donor macular tissue homogenates. Immunoreactive bands were identified and graded, and odds ratios (OR) calculated. Based on these findings, sera were immunoprecipitated, and subjected to 2D gel electrophoresis (GE). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to identify the targets recognized by circulating AAbs seen on 2D-GE, followed by ELISAs with recombinant proteins to confirm LC-MS/MS results, and quantify autoreactivities. Results: In AMD, 11 immunoreactive bands were significantly more frequent and 13 were significantly stronger than in controls. Nine of the more frequent bands also showed stronger reactivity. OR estimates ranged between 4.06 and 1.93, and all clearly excluded the null value. Following immunoprecipitation, 2D-GE and LC-MS/MS, five of the possible autoreactivity targets were conclusively identified: two members of the heat shock protein 70 (HSP70) family, HSPA8 and HSPA9; another member of the HSP family, HSPB4, also known as alpha-crystallin A chain (CRYAA); Annexin A5 (ANXA5); and Protein S100-A9, also known as calgranulin B that, when complexed with S100A8, forms calprotectin. ELISA testing with recombinant proteins confirmed, on average, significantly higher reactivities against all targets in AMD samples compared to controls. Conclusions: Consistent with other evidence supporting the role of inflammation and the immune system in AMD pathogenesis, AAbs were identified in AMD sera, including early-stage disease. Identified targets may be mechanistically linked to AMD pathogenesis because the identified proteins are implicated in autophagy, immunomodulation, and protection from oxidative stress and apoptosis. In particular, a role in autophagy activation is shared by all five autoantigens, raising the possibility that the detected AAbs may play a role in AMD via autophagy compromise and downstream activation of the inflammasome. Thus, we propose that the detected AAbs provide further insight into AMD pathogenesis and have the potential to contribute to disease biogenesis and progression.
- [Show abstract] [Hide abstract] ABSTRACT: Elevated levels of the phosphate-regulating hormone fibroblast growth factor 23 (FGF23) have been linked to greater risk of fractures in some studies, especially among individuals with chronic kidney disease (CKD). We evaluated FGF23 as a risk factor for bone loss and fractures in the Health, Aging, and Body Composition (Health ABC) study, which is a prospective biracial cohort of well-functioning adults aged 70 to 79 years recruited at two clinical centers in the United States. The sample for the bone mineral density (BMD) analyses consisted of 2234 participants who had at least two serial total hip areal BMD measures. The fracture analyses included 2786 participants, 567 of whom sustained a fracture during a median follow up of 4.95 years. Linear mixed-effects models were used for longitudinal measurements of total hip areal BMD and the proportional subdistribution hazard regression model subject to competing risks of death was used for risk of fracture. The median FGF23 was 46.7 (interquartile range [IQR] 36.7 to 60.2) pg/mL. The mean annualized percent change in total hip areal BMD did not vary significantly according to FGF23 quartile in all participants (p for trend=0.70), but the effect was modified by CKD status (adjusted p for interaction <0.001). Among participants with CKD, the unadjusted mean annualized percent change in total hip areal BMD was greater with higher levels of FGF23 (unadjusted p for trend=0.02), but the trend was attenuated with adjustment for estimated glomerular filtration rate and parathyroid hormone (adjusted p for trend=0.30). FGF23 was not significantly associated with fracture risk in crude (hazard ratio [HR] per doubling of FGF23, 0.97; 95% CI, 0.85 to 1.12) or adjusted models (HR per doubling of FGF23, 1.02; 95% CI, 0.86 to 1.22), and these findings were not modified by gender or CKD status. FGF23 levels are not associated with bone loss or fracture risk in older adults with low prevalence of CKD.
- [Show abstract] [Hide abstract] ABSTRACT: Objective: We aimed to determine whether hearing impairment (HI) in older adults is associated with the development of frailty and falls. Method: Longitudinal analysis of observational data from the Health, Aging and Body Composition study of 2,000 participants aged 70 to 79 was conducted. Hearing was defined by the pure-tone-average of hearing thresholds at 0.5, 1, 2, and 4 kHz in the better hearing ear. Frailty was defined as a gait speed of <0.60 m/s and/or inability to rise from a chair without using arms. Falls were assessed annually by self-report. Results: Older adults with moderate-or-greater HI had a 63% increased risk of developing frailty (adjusted hazard ratio [HR] = 1.63, 95% confidence interval [CI] = [1.26, 2.12]) compared with normal-hearing individuals. Moderate-or-greater HI was significantly associated with a greater annual percent increase in odds of falling over time (9.7%, 95% CI = [7.0, 12.4] compared with normal hearing, 4.4%, 95% CI = [2.6, 6.2]). Discussion: HI is independently associated with the risk of frailty in older adults and with greater odds of falling over time.
- [Show abstract] [Hide abstract] ABSTRACT: Background. Inflammation, slow gait, and depression individually are associated with mortality, yet little is known about the trajectories of these measures, their interrelationships, or their collective impact on mortality. Methods. Longitudinal latent class analysis was used to evaluate trajectories of depression (Center for Epidemiologic Studies Depression ≥ 10), slow gait ( 3.2 pg/mL) using data from the Health Aging and Body Composition Study. Logistic regression was used to identify their associations with mortality. Results. For each outcome, low-probability (n inflammation = 1,656, n slow gait = 1,471, n depression = 1,458), increasing-probability (n inflammation = 847, n slow gait = 880, n depression = 1,062), and consistently high-probability (n inflammation = 572, n slow gait = 724, n depression = 555) trajectories were identified, with 22% of all participants classified as having increasing or consistently high-probability trajectories on inflammation, slow gait, and depression (meaning probability of impairment on each outcome increased from low to moderate/high or remained high over 10 years). Trajectories of slow gait were associated with inflammation (r = .40, p < .001) and depression (r = .49, p < .001). Although worsening trajectories of inflammation were independently associated with mortality (p < .001), the association between worsening trajectories of slow gait and mortality was only present in participants with worsening depression trajectories (p < .01). Participants with increasing/consistently high trajectories of depression and consistently high trajectories of inflammation and slow gait (n = 247) have an adjusted-morality rate of 85.2%, greater than all other classification permutations. Conclusions. Comprehensive assessment of older adults is warranted for the development of treatment strategies targeting a high-mortality risk phenotype consisting of inflammation, depression, and slow gait speed.
- [Show abstract] [Hide abstract] ABSTRACT: Unlabelled: Obesity is a well-recognized risk factor for atrial fibrillation (AF), yet adiposity measures other than body mass index (BMI) have had limited assessment in relation to AF risk. We examined the associations of adiposity measures with AF in a biracial cohort of older adults. Given established racial differences in obesity and AF, we assessed for differences by black and white race in relating adiposity and AF. Methods: We analyzed data from 2,717 participants of the Health, Aging, and Body Composition Study. Adiposity measures were BMI, abdominal circumference, subcutaneous and visceral fat area, and total and percent fat mass. We determined the associations between the adiposity measures and 10-year incidence of AF using Cox proportional hazards models and assessed for their racial differences in these estimates. Results: In multivariable-adjusted models, 1-SD increases in BMI, abdominal circumference, and total fat mass were associated with a 13% to 16% increased AF risk (hazard ratio [HR] 1.14, 95% CI 1.02-1.28; HR 1.16, 95% CI 1.04-1.28; and HR 1.13, 95% CI 1.002-1.27). Subcutaneous and visceral fat areas were not significantly associated with incident AF. We did not identify racial differences in the associations between the adiposity measures and AF. Conclusion: Body mass index, abdominal circumference, and total fat mass are associated with risk of AF for 10years among white and black older adults. Obesity is one of a limited number of modifiable risk factors for AF; future studies are essential to evaluate how obesity reduction can modify the incidence of AF.
- [Show abstract] [Hide abstract] ABSTRACT: Objectives: To determine whether lower extremity sensorimotor peripheral nerve deficits are associated with reduced walking endurance in older adults. Design: Prospective cohort study with 6 years of follow-up. Setting: Two university research clinics. Participants: Community-dwelling older adults enrolled in the Health, Aging and Body Composition Study from the 2000-2001 annual clinical examination (N=2393; mean age ± SD, 76.5±2.9y; 48.2% men; 38.2% black) and a subset with longitudinal data (n=1178). Interventions: Not applicable. Main outcome measures: Participants underwent peripheral nerve function examination in 2000-2001, including peroneal motor nerve conduction amplitude and velocity, vibration perception threshold, and monofilament testing. Symptoms of lower extremity peripheral neuropathy included numbness or tingling and sudden stabbing, burning, pain, or aches in the feet or legs. The Long Distance Corridor Walk (LDCW) (400m) was administered in 2000-2001 and every 2 years afterward for 6 years to assess endurance walking performance over time. Results: In separate, fully adjusted linear mixed models, poor vibration threshold (>130μm), 10-g and 1.4-g monofilament insensitivity were each associated with a slower 400-m walk completion time (16.0s, 14.4s, and 6.9s slower, respectively; P<.05 for each). Poor motor amplitude (<1mV), poor vibration perception threshold, and 10-g monofilament insensitivity were related to greater slowing per year (4.7, 4.2, and 3.8 additional seconds per year, respectively; P<.05), although poor motor amplitude was not associated with initial completion time. Conclusions: Poorer sensorimotor peripheral nerve function is related to slower endurance walking and greater slowing longitudinally. Interventions to reduce the burden of sensorimotor peripheral nerve function impairments should be considered to help older adults maintain walking endurance-a critical component for remaining independent in the community.
- [Show abstract] [Hide abstract] ABSTRACT: Evidence of the association between chronic inflammation and the risk of colorectal cancer (CRC) and other obesity-related cancers (OBRC) remains inconsistent, possibly due to a paucity of studies examining repeated measures of inflammation. In the Health ABC prospective study of 2490 adults aged 70–79 years at baseline, we assessed whether circulating levels of three markers of systemic inflammation, IL-6, CRP and TNF-α, were associated with the risk of CRC and OBRC, a cluster including cancers of pancreas, prostate, breast and endometrium. Inflammatory markers were measured in stored fasting blood samples. While only baseline measures of TNF-α were available, IL-6 and CRP were additionally measured at Years 2, 4, 6 and 8. Multivariable Cox models were fit to determine whether tertiles and log-transformed baseline, updated and averaged measures of CRP and IL-6 and baseline measures of TNF-α were associated with the risk of incident cancer(s). During a median follow-up of 11.9 years, we observed 55 and 172 cases of CRC and OBRC, respectively. The hazard of CRC in the highest tertile of updated CRP was more than double that in the lowest tertile (HR = 2.29; 95% CI: 1.08–4.86). No significant associations were seen between colorectal cancer and IL-6 or TNF-α. Additionally, no significant associations were found between obesity-related cancers and the three inflammatory markers overall, but we observed a suggestion of effect modification by BMI and NSAID use. In summary, in this population, higher CRP levels were associated with increased risk of CRC, but not of OBRC. The findings provide new evidence that chronically-elevated levels of CRP, as reflected by repeated measures of this marker, may play a role in colorectal carcinogenesis in older adults. This article is protected by copyright. All rights reserved.
- [Show abstract] [Hide abstract] ABSTRACT: Functional independence with aging is an important goal for individuals and society. Simple prognostic indicators can inform health promotion and care planning, but evidence is limited by heterogeneity in measures of function. We performed a pooled analysis of data from seven studies of 27,220 community-dwelling older adults aged 65 or older with baseline gait speed, followed for disability and mortality. Outcomes were incident inability or dependence on another person in bathing or dressing; and difficulty walking ¼ - ½ mile or climbing 10 steps within 3 years. Participants with faster baseline gait had lower rates of incident disability. In subgroups (defined by 0.2 m/s-wide intervals from <0.4 to ≥1.4 m/s) with increasingly greater gait speed, 3-year rates of bathing or dressing dependence trended from 10% to 1% in men, and from 15% to 1% in women, while mobility difficulty trended from 47% to 4% in men and 40% to 6% in women. The age-adjusted relative risk ratio per 0.1 m/s greater speed for bathing or dressing dependence in men was 0.68 (0.57-0.81) and in women: 0.74 (0.66-0.82); for mobility difficulty, men: 0.75 (0.68-0.82), women: 0.73 (0.67-0.80). Results were similar for combined disability and mortality. Effects were largely consistent across subgroups based on age, gender, race, body mass index, prior hospitalization, and selected chronic conditions. In the presence of multiple other risk factors for disability, gait speed significantly increased the area under the receiver operator characteristic curve. In older adults, gait speed predicts 3 year incidence of bathing or dressing dependence, mobility difficulty, and a composite outcome of disability and mortality. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
- [Show abstract] [Hide abstract] ABSTRACT: Depression and disability are closely linked. Less is known regarding clinical and subclinical depressive symptoms over time and risk of disability and mortality. Responses to the Center for Epidemiologic Studies Short Depression scale (CES-D10) were assessed over a 4-year period in men (n = 1032) and women (n = 1070) aged 70-79 years initially free from disability. Depressive symptom trajectories were defined with group-based models. Disability (2 consecutive reports of severe difficulty walking one-quarter mile or climbing 10 steps) and mortality were determined for 9 subsequent years. Hazard ratios (HRs) were estimated using Cox proportional hazards adjusted for covariates. Three trajectories were identified: persistently nondepressed (54% of men, 54% of women, mean baseline CES-D10: 1.16 and 1.46), mildly depressed and increasing (40% of men, 38% of women, mean baseline CES-D10: 3.60 and 4.35), and depressed and increasing (6% of men, 8% of women, mean baseline CES-D10: 7.44 and 9.61). Disability and mortality rates per 1,000 person years were 41.4 and 60.3 in men and 45.8 and 41.9 in women. Relative to nondepressed, men in the mildly depressed (HR = 1.45, 95% confidence interval [CI] 1.11-1.89) and depressed trajectories (HR = 2.12, 95% CI 1.33-3.38) had increased disability; women in the depressed trajectory had increased disability (HR = 2.02, 95% CI 1.37-2.96). Men in the mildly depressed (HR = 1.24, 95% CI 1.01-1.52) and depressed trajectories (HR = 1.63, 95% CI 1.10-2.41) had elevated mortality risk; women exhibited no mortality risk. Trajectories of depressive symptoms without recovery may predict disability and mortality in apparently healthy older populations, thus underscoring the importance of monitoring depressive symptoms in geriatric care. Published by Oxford University Press on behalf of the Gerontological Society of America 2015.
VU University AmsterdamAmsterdamo, North Holland, Netherlands
University of PittsburghPittsburgh, Pennsylvania, United States
The University of MemphisMemphis, Tennessee, United States
Johns Hopkins MedicineBaltimore, Maryland, United States