Older blacks are less likely to receive guideline-recommended antilipemic therapy and achieve lipid control than older whites due in part to out-of-pocket costs. We sought to determine whether racial differences in antilipemic use and lipid control narrowed after Medicare Part D’s implementation.
This before-after study included 1091 black and white adults age >70 with coronary heart disease and/or diabetes mellitus from the Health Aging and Body Composition Study. Primary outcomes were antilipemic use and LDL-C control. Key independent variables were race, time (pre- vs. post-Part D), and their interaction.
Before Part D, fewer blacks than whites reported taking an antilipemic (32.70% vs 49.35%) and this difference was sustained after Part D (blacks 48.30% vs whites 64.57%). Multivariable generalized estimating equations confirmed no post Part D change in racial differences in antilipemic use (adjusted ratio of the odds ratios [AROR] 1.07, 95% CI 0.79–1.45). Compared to whites, more blacks had poor lipid control both before Part D (24.30% vs 12.36% respectively) and after Part D (24.46% vs 13.72% respectively), with no post Part D change in racial differences in lipid control (AROR 0.82, 95% CI 0.51–1.33).
While antilipemic use increased after Medicare Part D for both races, this policy change was associated neither with a change in lipid control for either racial group nor in the racial differences in antilipemic use or lipid control.
Slow walking speed is strongly associated with older age, but mechanisms underlying this relationship are not well-understood. We hypothesize that slow gait represents a compensatory strategy to reduce the energetic cost of walking with age.
Community-dwelling volunteers from the Baltimore Longitudinal Study of Aging (BLSA).
420 community-dwelling persons aged 32 to 96 (mean 68.1 ± 12.5) who underwent a physical examination, physical function testing, and energy expenditure assessment.
Energy expenditure per minute (ml/kg/min) and per meter (ml/kg/m) during 2.5 minutes of overground walking at customary speed, and usual gait speed over six meters (m/s) were examined. General linear regression models were used to assess the relationship between customary walking energy expenditure and usual gait speed, adjusted for potential confounders including smoking, medical diagnoses, walking-related pain, and balance difficulty.
Usual gait speed was slower with increasing age after age 65. Energy expenditure per minute during customary walking averaged 13.0 ml/kg/min (± 2.8) and was independent of age (ρ < 0.01, p = .88). In contrast, energy expenditure per meter walked was progressively higher after age 65 (ρ = 0.35, p < .001) and heightened after age 80 (ρ = 0.57, p < .001), mirroring the observed pattern of usual gait speed. This relationship remained significant after adjusting for multiple impairments and comorbidities.
These observations support the hypothesis that slower gait at older ages may reflect a compensatory action to offset a greater energetic cost of walking associated with aging and chronic conditions. Future studies should evaluate the specific mechanisms that contribute to this phenomenon as novel targets for clinical intervention.
Energy Expenditure; Gait Speed; Physical Function
While several studies report an association between prevalent diabetes mellitus (DM) and cognitive impairment, less is known about incident DM in late life and cognitive decline. Glycemic control among elders with DM may also be associated with cognitive function, but findings are inconsistent.
To determine if prevalent and incident DM increases risk of cognitive decline, and if, among elders with DM, poor glucose control is related to worse cognitive performance.
Prospective cohort study.
Health Aging and Body Composition Study at two community clinics.
A total of 3,069 elders (mean age 74.2 years; 42% black; 52% female).
Main Outcome Measures
Participants completed the Modified Mini-Mental State Examination (3MS) and Digit Symbol Substitution Test (DSST) at baseline and selected intervals over 10 years. DM status was determined at baseline and during follow-up visits. Glycosylated hemoglobin A1c (HbA1c) was measured at year 1 (baseline), 4, 6, and 10 from fasting whole blood.
At baseline 717 (23.4%) participants had prevalent DM and 2352 (76.6%) were without diabetes, 159 of whom developed incident DM during follow-up. Participants with prevalent DM had lower baseline test scores than participants without DM (3MS: 88.8 vs. 90.9; DSST: 32.5 vs 36.3, respectively; |t|=6.09, p=0.001 for both tests). Results from mixed-effects models showed a similar pattern for 9-year decline (3MS: −6.0 vs. −4.5 point decline; |t|=2.66, p=0.008; DSST: −7.9 vs. −5.7, point decline; |t|=3.69, p=0.001, respectively). Participants with incident DM tended to have baseline and 9-year decline scores between the other two groups but were not statistically different from the group without diabetes. Multivariate adjustment for demographics and medical co-morbidities produced similar results. Among participants with prevalent DM, HbA1c level was associated with lower average mean cognitive scores (3MS p for overall=0.003; DSST p for overall=0.04), even after multivariate adjustment.
Among well-functioning older adults, DM and poor glucose control among those with DM are associated with worse cognitive function and greater decline. This suggests severity of DM may contribute to accelerated cognitive aging.
Associations among personality as measured by the Five Factor Model, physical activity, and muscle strength were assessed using data from the Baltimore Longitudinal Study of Aging (N = 1220, age: mean = 58, SD = 16). General linear modeling with adjustment for age, sex, race, and body mass index, and bootstrapping for mediation were used. We found neuroticism and most of its facets to negatively correlate with strength. The extraversion domain and its facets of warmth, activity, and positive-emotions were positively correlated with strength, independent of covariates. Mediation analysis results suggest that these associations are partly explained by physical activity level. Findings extend the evidence of an association between personality and physical function to its strength component and indicate health behavior as an important pathway.
Personality; Neuroticism; Extraversion; Agreeableness; Physical activity; Muscle strength
Peak energy expenditure is highly correlated with usual gait speed, however it is unknown whether the energetic cost of walking is also an important contributor to usual gait speed when considered as a component of peak walking capacity.
The energetic cost of five minutes of slow treadmill walking (0.67 m/s), peak overground walking energy expenditure, and usual gait speed over 6 meters were assessed cross-sectionally in 405 adults aged 33 to 94 in the Baltimore Longitudinal Study of Aging.
Average energy expenditure during slow and peak sustained walking were 8.9 (± 1.4) and 18.38 (± 4.8) ml/kg/min, respectively. Overall, the energetic cost of slow walking as a percentage of peak walking energy expenditure was strongly associated with usual gait speed (p < 0.001), however in stratified analyses, this association was maintained only in those with peak walking capacity below 18.3 ml/kg/min (p = 0.04), the threshold associated with independent living.
In older persons with substantially reduced peak walking capacity, the energetic cost of walking is associated with gait speed, particularly when peak walking capacity nears the minimum level considered necessary for independent living. Thus, optimal habilitation in older frail persons may benefit from both improving fitness and reducing the energetic cost of walking.
Energy Expenditure; Walking Efficiency; Usual Gait Speed; Physical Function
Characterization of long-term health trajectory in older individuals is important for proactive health management. However, the relative prognostic value of information contained in clinical profiles of nonfrail older adults is often unclear.
We screened 825 phenotypic and genetic measures evaluated during the Health, Aging, and Body Composition Study (Health ABC) baseline visit (3,067 men and women aged 70–79). Variables that best predicted mortality over 13 years of follow-up were identified using 10-fold cross-validation.
Mortality was most strongly associated with low Digit Symbol Substitution Test (DSST) score (DSST<25; 21.9% of cohort; hazard ratio [HR]=1.87±0.06) and elevated serum cystatin C (≥1.30 mg/mL; 12.1% of cohort; HR=2.25±0.07). These variables predicted mortality better than 823 other measures, including baseline age and a 45-variable health deficit index. Given elevated cystatin C (≥1.30 mg/mL), mortality risk was further increased by high serum creatinine, high abdominal visceral fat density, and smoking history (2.52≤HR ≤3.73). Given a low DSST score (<25) combined with low-to-moderate cystatin C (<1.30 mg/mL), mortality risk was highest among those with elevated plasma resistin and smoking history (1.90≤HR≤2.02).
DSST score and serum cystatin C warrant priority consideration for the evaluation of mortality risk in older individuals. Both variables, taken individually, predict mortality better than chronological age or a health deficit index in well-functioning older adults (ages 70–79). DSST score and serum cystatin C can thus provide evidence-based tools for geriatric assessment.
It has been hypothesized that cellular damage caused by oxidative stress is associated with late-life depression but epidemiological evidence is limited. In the present study we evaluated the association between urinary 8-iso-prostaglandin F2α (8-iso-PGF2α), a biomarker of lipid peroxidation, and depressed mood in a large sample of community-dwelling older adults. Participants were selected from the Health, Aging and Body Composition study, a community-based longitudinal study of older persons (aged 70–79 years). The present analyses was based on a subsample of 1027 men and 948 women free of mobility disability. Urinary concentration of 8-iso-PGF2α was measured by radioimmunoassay methods and adjusted for urinary creatinine. Depressed mood was defined as a score greater than 5 on the 15-item Geriatric Depression Scale and/or use of antidepressant medications. Depressed mood was present in 3.0% of men and 5.5% of women. Depressed men presented higher urinary concentrations of 8-iso-PGF2α than non-depressed men even after adjustment for multiple sociodemographic, lifestyle and health factors (p = 0.03, Cohen’s d = 0.30). This association was not present in women (depressed status-by-sex interaction p = 0.04). Our study showed that oxidative damage may be linked to depression in older men from a large sample of the general population. Further studies are needed to explore whether the modulation of oxidative stress may break down the link between late-life depression and its deleterious health consequences.
To identify clinical measures that aid detection of impending severe mobility difficulty in older women.
Cross-sectional and longitudinal cohort study.
Urban community in Baltimore, Maryland.
One thousand two community-dwelling, moderate to severely disabled women aged 65 and older in the Women’s Health and Aging Study I.
Self-report and performance measures representing six domains necessary for mobility: central and peripheral nervous systems, muscles, bones and joints, perception, and energy. Severe mobility difficulty was defined as usual gait of 0.5 m/s or less, any reported difficulty walking across a small room, or dependence on a walking aid during a 4-m walking test.
Four hundred sixty-seven out of 984 (47%) had severe mobility difficulty at baseline, and 104/474 (22%) developed it within 12 months. Baseline mobility difficulty was correlated with poor vision, knee pain, feelings of helplessness, inability to stand with feet side by side for 10 seconds, difficulty keeping balance while dressing or walking, inability to rise from a chair five times, and cognitive impairment. Of these, knee pain (odds ratio (OR) = 1.74, 95% confidence interval (CI) = 1.05–2.89), helplessness (OR = 1.87, 95% CI = 1.10–3.24), poor vision (OR = 2.03, 95% CI = 1.06–3.89), inability to rise from a chair five times (OR = 2.50, 95% CI = 1.15–5.41), and cognitive impairment (OR = 4.75, 95% CI = 1.67–13.48) predicted incident severe mobility difficulty within 12 months, independent of age.
Five simple measures may aid identification of disabled older women at high risk of severe mobility difficulty. Further studies should determine generalizability to men and higher-functioning individuals.
aging; mobility difficulty; clinical assessment
Both subclinical hypothyroidism and the metabolic syndrome have been associated with increased risk of coronary heart disease events. It is unknown if the prevalence and incidence of metabolic syndrome is higher as TSH levels increase, or in individuals with subclinical hypothyroidism. We sought to determine the association between thyroid function and the prevalence and incidence of the metabolic syndrome in a cohort of older adults.
Data was analyzed from the Health, Aging, and Body Composition Study, a prospective cohort of 3,075 community-dwelling US adults.
2,119 participants with measured TSH and data on metabolic syndrome components were included in the analysis.
TSH was measured by immunoassay. Metabolic syndrome was defined per revised ATP III criteria.
At baseline, 684 participants met criteria for metabolic syndrome. At 6yr follow-up, incident metabolic syndrome developed in 239 individuals. In fully adjusted models, each unit increase in TSH was associated with a 3% increase in the odds of prevalent metabolic syndrome (OR 1.03, 95% CI 1.01–1.06, p=0.02), and the association was stronger for TSH within the normal range (OR 1.16, 95% CI 1.03–1.30, p=0.02). Subclinical hypothyroidism with a TSH>10mIU/L was significantly associated with increased odds of prevalent metabolic syndrome (OR 2.3, 95% CI 1.0–5.0, p=0.04); the odds of incident MetS was similar (OR 2.2), but the confidence interval was wide (0.6–7.5).
Higher TSH levels and subclinical hypothyroidism with a TSH>10 mIU/L are associated with increased odds of prevalent but not incident metabolic syndrome.
Thyroid Function; Metabolic Syndrome; Subclinical Hypothyroidism
Older adults with hyperkyphosis are at increased risk of falls, fractures, and functional decline. Modifiable risk factors for hyperkyphosis have not been well studied. Our objective was to determine whether spinal muscle area and density are associated with hyperkyphosis, independent of age, race, sex, bone mineral density, and trunk fat.
Using data from the Pittsburgh site of the Health, Aging, and Body Composition study, we performed a baseline cross-sectional analysis. Participants were black and white men and women 70–79 years old (N = 1172), independent in activities of daily living and able to walk ¼ mile and up 10 steps without resting. We measured Cobb’s angle of kyphosis from supine lateral scout computed tomography scans, and categorized hyperkyphosis as Cobb’s angle >40°. Axial images from lateral scout computed tomography scans assessed spinal extensor muscle cross-sectional area and density (proxy for fat infiltration).
In our sample, 21% had hyperkyphosis. Prevalence in black men was 11%; in white men, 17%; in black women, 26%; and in white women, 30%. In multivariate analysis, each standard deviation increase in muscle density was associated with a 29% reduction in the odds of hyperkyphosis, independent of covariates. Muscle area was not significantly associated with hyperkyphosis.
Lower spinal muscle density is associated with hyperkyphosis in healthy community-dwelling older adults. This potentially modifiable risk factor could be targeted in exercise interventions. Randomized trials are needed to determine whether an exercise program targeting spinal muscle density reduces hyperkyphosis and in turn improves health outcomes.
Kyphosis; Hyperkyphosis; Prevalence; Spinal muscle; Fat infiltration
Personality traits and cardiorespiratory fitness in older adults are reliable predictors of health and longevity. We examined the association between personality traits and energy expenditure at rest (basal metabolic rate) and during normal and maximal sustained walking. Personality traits and oxygen (VO2) consumption were assessed in 642 participants from the Baltimore Longitudinal Study of Aging. Results indicate that personality traits were mostly unrelated to resting metabolic rate and energy expenditure at normal walking pace. However, those who scored lower on neuroticism (r = −0.12) and higher on extraversion (r = 0.11), openness (r = 0.13), and conscientiousness (r = 0.09) had significantly higher energy expenditure at peak walking pace. In addition to greater aerobic capacity, individuals with a more resilient personality profile walked faster and were more efficient in that they required less energy per meter walked. The associations between personality and energy expenditure were not moderated by age or sex, but were in part explained by the proportion of fat mass. In conclusion, differences in personality may matter the most during more challenging activities that require cardiorespiratory fitness. These findings suggest potential pathways that link personality to health outcomes, such as obesity and longevity.
Theoretical definitions of sarcopenia traditionally emphasize age-related loss of muscle strength; however, most analyses of the association between strength and mobility examine strength at a single time point. This study sought to identify sex-specific cutpoints for muscle strength and power (at one time point) and 3-year changes in strength and power that would maximize prediction of 3-year mobility decline.
Longitudinal analysis of 934 adults aged ≥65 years enrolled in the Invecchiare in Chianti study was conducted. Grip strength, knee extension strength, and lower extremity power were measured at baseline and 3 years postenrollment. Mobility function (gait speed and self-reported mobility disability) was measured at 3 and 6 years postenrollment. Classification and regression tree analysis was used to predict mobility decline from Years 3 to 6.
Men with knee extension strength <19.2 kg and grip strength <39.0 kg had clinically meaningful declines in gait speed of .24 m/s. Furthermore, men with power <105 W were nearly nine times more likely to develop incident mobility disability (likelihood ratio = 8.68; 95% confidence interval = 3.91, 19.44). Among women, knee extension strength <18.0 kg was associated with a minimal gait speed decline of 0.06 m/s, and women with leg power <64 W were three times more likely to develop incident mobility disability (likelihood ratio = 3.01; 95% confidence interval = 1.79, 5.08). Three-year changes in strength and power did not predict mobility decline in either sex.
Findings suggest that strength and power measured at one time point are more predictive of mobility decline than 3-year changes and that low strength and power are particularly powerful risk factors in men.
Strength; Sarcopenia; Mobility decline
Stiffness of the central arteries in aging may contribute to cerebral microvascular disease independent of hypertension and other vascular risk factors. Few studies of older adults have evaluated the association of central arterial stiffness with longitudinal cognitive decline.
We evaluated associations of aortic pulse wave velocity (centimeters per second), a measure of central arterial stiffness, with cognitive function and decline in 552 participants in the Health, Aging, and Body Composition (Health ABC) study Cognitive Vitality Substudy (mean age ± SD = 73.1 ± 2.7 years, 48% men and 42% black). Aortic pulse wave velocity was assessed at baseline via Doppler-recorded carotid and femoral pulse waveforms. Global cognitive function, verbal memory, psychomotor, and perceptual speed were evaluated over 6 years.
After adjustment for demographics, vascular risk factors, and chronic conditions, each 1 SD higher aortic pulse wave velocity (389 cm/s) was associated with poorer cognitive function: −0.11 SD for global function (SE = 0.04, p < .01), −0.09 SD for psychomotor speed (SE = 0.04, p = .03), and −0.12 SD for perceptual speed (SE = 0.04, p < .01). Higher aortic pulse wave velocity was also associated with greater decline in psychomotor speed, defined as greater than 1 SD more than the mean change (odds ratio = 1.42 [95% confidence interval = 1.06, 1.90]) but not with verbal memory or longitudinal decline in global function, verbal memory, or perceptual speed. Results were consistent with mixed models of decline in each cognitive test.
In well-functioning older adults, central arterial stiffness may contribute to cognitive decline independent of hypertension and other vascular risk factors.
Aging; Arterial stiffness; Cognitive decline
To examine the prevalence and correlates of non-opioid and opioid analgesic use and descriptively evaluate potential undertreatment in a sample of community-dwelling elders with symptomatic knee and/or hip osteoarthritis (OA).
Health, Aging and Body Composition Study
652 participants attending the year 6 visit (2002-03) with symptomatic knee and/or hip OA.
Analgesic use was defined as taking ≥ 1 non-opioid and/or ≥ 1 opioid receptor agonist. Non-opioid and opioid doses were standardized across all agents by dividing the daily dose used by the minimum effective analgesic daily dose. Inadequate pain control was defined as severe/extreme OA pain in the past 30 days from a modified Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).
Just over half (51.4%) reported taking at least one non-opioid analgesic and approximately 10% were taking an opioid, most (88.5%) of whom also took a non-opioid. One in five participants (19.3%) had inadequate pain control, 39% of whom were using < 1 standardized daily dose of either a non-opioid or opioid analgesic. In adjusted analyses, severe/extreme OA pain was significantly associated with both non-opioid (adjusted odds ratio [AOR]=2.44; 95% confidence interval [95% CI]=1.49-3.99) and opioid (AOR=2.64; 95% CI, 1.26-5.53) use.
Although older adults with severe/extreme knee and/or hip OA pain are more likely to take analgesics than those with less severe pain, a sizable proportion take less than therapeutic doses and thus may be undertreated. Further research is needed to examine barriers to optimal analgesic use.
Aged; Analgesic; Osteoarthritis
The mechanisms that underlie the association between abdominal obesity and depression risk in older persons are not well known, but the “leptin hypothesis” of depression suggests that leptin resistance may be involved in mood regulation. We tested whether high circulatory concentration of leptin, alone and in combination with visceral adiposity, is associated with onset of depression in a sample of older persons.
Participants were 1220 men and 1282 women aged 70–79 years, enrolled in the Health, Aging and Body Composition study. Plasma concentration of leptin and abdominal visceral fat ascertained by computed tomography were assessed at baseline (April 1997 – June 1998). Onset of depression was defined as a Center for Epidemiological Studies-Depression Scale 10-item score ≥ 10 and/or new antidepressant medication use at any annual visit over a 5-year follow-up.
Higher leptin was associated with the risk of depression onset in men with high visceral fat (HR=1.25,95%CI=1.06–1.46, p=0.01) but not in those with normal visceral fat (HR=0.98,95%CI=0.80–1.19, p=0.80) (leptin*visceral fat p=0.04). No interaction between leptin and visceral fat was detected in the analysis focusing on women (p=0.90).
In older men, high leptin was associated with an increased onset of depressive symptoms especially in the presence of abdominal obesity, suggesting that underlying leptin resistance may play a role in this link. Differences in visceral fat levels and metabolic consequences may explain the absence of this association in women. These findings suggest a potential biological link between depression, obesity and their joint association with negative health outcomes.
leptin; depression; obesity; aging
This study examines the relationship between race and mobility over 5 years in initially well-functioning older adults and evaluates how a broad set of socioeconomic status indicators affect this relationship.
Data were from 2,969 black and white participants aged 70–79 from the Health, Aging, and Body Composition study. Mobility parameters included self-reported capacity to walk a quarter mile and climb 10 steps and usual gait speed. Incident mobility limitation was defined as reported difficulty walking a quarter mile or climbing 10 steps at two consecutive semiannual assessments. Gait speed decline was defined as a 4% reduction in speed per year.
At baseline, even though all participants were free of mobility limitation, blacks had slower walking speed than their white counterparts, which was not explained by poverty, education, reading level, or income adequacy. After 5 years, accounting for age, site, and baseline mobility, blacks were more likely to develop mobility limitation than whites. Adjusting for prevalent conditions at baseline eliminated this difference in women; controlling for education eliminated this difference in men. No differences in gait speed decline were identified.
Higher rates of mobility loss observed in older blacks relative to older whites appear to be a function of both poorer initial mobility status and existing health conditions particularly for women. Education may also play a role especially for men.
Race disparities—Functional limitations—SES—Disability
Diabetes may impact gait mechanics before onset of frank neuropathies and other associated threats to mobility. This study aims to characterize gait pattern alterations of type 2 diabetic adults without peripheral neuropathy during walking at maximum speed (fast-walking) as well as at self-selected speed (usual-walking). One-hundred and eighty-six participants aged 60 to 87 from the Baltimore Longitudinal Study of Aging (BLSA) able to walk unassisted and without peripheral neuropathy were classified as non-diabetic (N = 160) or having type 2 diabetes (N=26). Gait parameters from the fast-walking and usual-walking tests were compared between participants with and without type 2 diabetes. Participants with diabetes had a shorter stride length for fast-walking (p = 0.033) and a longer percentage of the gait cycle with the knee in 1st flexion for both fast- and usual-walking (p = 0.033, and 0.040, respectively) than non-diabetic participants. Participants with diabetes exhibited a smaller hip range of motion in the sagittal plane during usual-walking compared to non-diabetics (p = 0.049). During fast-walking, participants with diabetes used lower ankle generative mechanical work expenditure (MWE) and higher knee absorptive MWE compared to non-diabetic persons (p = 0.021, and 0.018, respectively). These findings suggest that individuals with type 2 diabetes without overt peripheral neuropathy exhibit altered and less efficient gait patterns than non-diabetic persons. These alterations are more apparent during walking at a maximum speed indicating that maximum gait testing may be useful for identifying early threats to mobility limitations in older adults with type 2 diabetes.
type 2 diabetes; aging; gait; mobility limitation; peripheral neuropathy; mechanical work expenditure
Angiotensin-converting enzyme (ACE) inhibitors and statin medications have been proposed as potential agents to prevent or delay physical disability; yet limited research has evaluated whether such use in older community dwelling adults is associated with a lower risk of incident mobility limitation.
Longitudinal cohort study
Health, Aging and Body Composition (Health ABC)
3055 participants who were well functioning at baseline (e.g., no mobility limitations).
Summated standardized daily doses (low, medium and high) and duration of ACE inhibitor and statin use was computed. Mobility limitation (two consecutive self-reports of having any difficulty walking 1/4 mile or climbing 10 steps without resting) was assessed every 6 months after baseline. Multivariable Cox proportional hazard analyses were conducted adjusting for demographics, health status, and health behaviors.
At baseline, ACE inhibitors and statins were used by 15.2% and 12.9%, respectively and both increased to over 25% by year 6. Over 6.5 years of follow-up, 49.8% had developed mobility limitation. In separate multivariable models, neither ACE inhibitor (multivariate hazard ratio [HR] 0.95; 95% confidence interval [CI] 0.82–1.09) nor statin use (multivariate HR 1.02; 95% CI 0.87–1.17) was associated with a lower risk for mobility limitation. Similar findings were seen in analyses examining dose- and duration-response relationships and sensitivity analyses restricted to those with hypertension.
These findings indicate that ACE inhibitors and statins widely prescribed to treat hypertension and hypercholesterolemia, respectively do not lower risk of mobility limitation, an important life quality indicator.
Background. The NCEP metabolic syndrome (MetS) is a combination of dichotomized interrelated risk factors from predominantly Caucasian populations. We propose a continuous MetS score based on principal component analysis (PCA) of the same risk factors in a multiethnic cohort and compare prediction of incident CVD events with NCEP MetS definition. Additionally, we replicated these analyses in the Health, Aging, and Body composition (Health ABC) study cohort. Methods and Results. We performed PCA of the MetS elements (waist circumference, HDL, TG, fasting blood glucose, SBP, and DBP) in 2610 Caucasian Americans, 801 Chinese Americans, 1875 African Americans, and 1494 Hispanic Americans in the multiethnic study of atherosclerosis (MESA) cohort. We selected the first principal component as a continuous MetS score (MetS-PC). Cox proportional hazards models were used to examine the association between MetS-PC and 5.5 years of CVD events (n = 377) adjusting for age, gender, race, smoking and LDL-C, overall and by ethnicity. To facilitate comparison of MetS-PC with the binary NCEP definition, a MetS-PC cut point was chosen to yield the same 37% prevalence of MetS as the NCEP definition (37%) in the MESA cohort. Hazard ratio (HR) for CVD events were estimated using the NCEP and Mets-PC-derived binary definitions. In Cox proportional models, the HR (95% CI) for CVD events for 1-SD (standard deviation) of MetS-PC was 1.71 (1.54–1.90) (P < 0.0001) overall after adjusting for potential confounders, and for each ethnicity, HRs were: Caucasian, 1.64 (1.39–1.94), Chinese, 1.39 (1.06–1.83), African, 1.67 (1.37–2.02), and Hispanic, 2.10 (1.66-2.65). Finally, when binary definitions were compared, HR for CVD events was 2.34 (1.91–2.87) for MetS-PC versus 1.79 (1.46–2.20) for NCEP MetS. In the Health ABC cohort, in a fully adjusted model, MetS-PC per 1-SD (Health ABC) remained associated with CVD events (HR = 1.21, 95%CI 1.12–1.32) overall, and for each ethnicity, Caucasian (HR = 1.24, 95%CI 1.12–1.39) and African Americans (HR = 1.16, 95%CI 1.01–1.32). Finally, when using a binary definition of MetS-PC (cut point 0.505) designed to match the NCEP definition in terms of prevalence in the Health ABC cohort (35%), the fully adjusted HR for CVD events was 1.39, 95%CI 1.17–1.64 compared with 1.46, 95%CI 1.23–1.72 using the NCEP definition. Conclusion. MetS-PC is a continuous measure of metabolic syndrome and was a better predictor of CVD events overall and in individual ethnicities. Additionally, a binary MetS-PC definition was better than the NCEP MetS definition in predicting incident CVD events in the MESA cohort, but this superiority was not evident in the Health ABC cohort.
Depression has been hypothesized to result in abdominal obesity through the accumulation of visceral fat. No large study has tested this hypothesis longitudinally.
To examine whether depressive symptoms predict an increase in abdominal obesity in a large population-based sample of well-functioning older persons.
The Health, Aging, and Body Composition Study, an ongoing prospective cohort study, with 5 years of follow-up.
Community-dwelling older persons residing in the areas surrounding Pittsburgh, Pennsylvania, and Memphis, Tennessee.
2088 well-functioning white and black persons aged 70–79 years.
Main Outcome Measures
Baseline depression was defined as a Center for Epidemiological Studies Depression (CES-D) score of ≥ 16. At baseline and after 5 years, overall obesity measures included body mass index and percent body fat (measured by dual energy x-ray absorptiometry). Abdominal obesity measures included waist circumference, sagittal diameter, and visceral fat (measured by computed tomography).
After adjustment for sociodemographics, lifestyle, diseases and overall obesity, baseline depression was associated with a 5-year increase in sagittal diameter (β=.054, p=.01) and visceral fat (β=.080, p=.001).
This study shows that depressive symptoms result in an increase in abdominal obesity, independent of overall obesity, suggesting that there may be specific pathophysiological mechanisms which link depression with visceral fat accumulation. These results might also help explain why depression increases risk of diabetes and cardiovascular disease.
This study examined the association of physical fitness, as assessed by ability and time to complete a 400-meter walk, on changes in body composition and muscle strength over a subsequent 7-year period.
Prospective observational cohort study
Memphis, Tennessee and Pittsburgh, Pennsylvania
2,949 black and white men and women aged 70-79 participating in the Health, Aging and Body Composition (Health ABC) study.
Body composition (fat and bone-free lean mass) was assessed by dual-energy x-ray absorptiometry in years 1-6, and 8. Knee extension strength was measured with isokinetic dynamometry and grip strength with isometric dynamometry in years 1,2,4,6, and 8.
Compared to very fit men and women at baseline, less fit people had a higher weight, higher total percent fat, and lower total percent lean mass (p<0.01). Additionally, the least fit lost significantly more weight, fat mass, and lean mass over time compared to the very fit (p<0.01). Very fit people had the highest grip strength and knee extensor strength at baseline and follow-up; the decline in muscle strength was similar in every fitness group.
Low fitness in old age was associated with greater weight loss and loss of lean mass relative to having high fitness. Despite having lower muscle strength, the rate of decline in the least fit persons was similar to the most fit. In clinical practice, a long distance walk test as a measure of fitness might be useful to identify people at risk for these adverse health outcomes.
body composition; aging; fitness; muscle strength; muscle mass
The Drug Burden Index (DBI), a measure of exposure to anticholinergic and sedative medications, has been independently associated with physical and cognitive function in a cross-sectional analysis of community dwelling older persons participating in the Health, Aging and Body Composition (Health ABC) study. Here we evaluate the association between DBI and functional outcomes in Health ABC participants over five years.
DBI was calculated at years 1 (baseline), 3 and 5 and a measure of the area under the curve for DBI (AUCDB) over the whole study period was devised and calculated. Physical performance was measured using the short physical performance battery (SPPB), usual gait speed, and grip strength. The association of DBI at each time point and AUCDB with year 6 function was analyzed in data from participants with longitudinal functional measures, controlling for socio-demographics, co-morbidities and baseline function.
Higher DBI at years 1, 3 and 5 was consistently associated with poorer function at year 6. On multivariate analysis, a one unit increase in AUCDB predicted decreases in SPPB score of 0.08 (p = 0.01), gait speed of 0.01 m/s (p=0.004), and grip strength of 0.27 kg (p=0.004) at year 6.
Increasing exposure to medication with anticholinergic and sedative effects, measured with DBI, is associated with lower objective physical function over five years in community dwelling older people.
The protective mechanisms by which some obese individuals escape the detrimental metabolic consequences of obesity are not understood. This study examined differences in body fat distribution and adipocytokines in obese older persons with and without metabolic syndrome. Additionally, we examined whether adipocytokines mediate the association between body fat distribution and metabolic syndrome. Data were from 729 obese men and women (BMI≥30kg/m2), aged 70-79 participating in the Health, Aging and Body Composition (Health ABC) study. Thirty-one percent of these obese men and women did not have metabolic syndrome. Obese persons with metabolic syndrome had significantly more abdominal visceral fat (men:p=0.04; women:p<0.01) and less thigh subcutaneous fat (men:p=0.09; women:p<0.01) than those without metabolic syndrome. Additionally, those with metabolic syndrome had significantly higher levels of IL-6, TNF-α and PAI-1 than individuals without metabolic syndrome. Per standard deviation (SD) higher in visceral fat, the likelihood of metabolic syndrome significantly increased in women (odds ratio (OR):2.16, 95% confidence interval (CI):1.59-2.94). In contrast, the likelihood of metabolic syndrome decreased in both men (OR:0.56, 95%CI:0.39-0.80) and women (OR:0.49, 95%CI:0.34-0.69) with each SD higher in thigh subcutaneous fat. These associations were partly mediated by adipocytokines; the association between thigh subcutaneous fat and metabolic syndrome was no longer significant in men. In summary, metabolically healthy obese older persons had a more favorable fat distribution, characterized by lower visceral fat and greater thigh subcutaneous fat and a more favorable inflammatory profile compared to their metabolically unhealthy obese counterparts.
Telomere shortening is a marker of cellular aging and has been associated with risk of Alzheimer’s disease. Few studies have determined if telomere length is associated with cognitive decline in non-demented elders. We prospectively studied 2,734 non-demented elders (mean age: 74 years). We measured cognition with the Modified Mini-Mental State Exam (3MS) and Digit Symbol Substitution Test (DSST) repeatedly over 7 years. Baseline telomere length was measured in blood leukocytes and classified by tertile as “short”, “medium”, or “long”. At baseline, longer telomere length was associated with better DSST score (36.4, 34.9 and 34.4 points for long, medium and short, p <0.01) but not for change in score. However, seven-year 3MS change scores were less among those with longer telomere length (−1.7 points vs. −2.5 and −2.9, p = 0.01). Findings were similar after multivariable adjustment for age, gender, race, education, assay batch, and baseline score. There was a borderline statistically significant interaction for telomere length and APOE e4 on 3MS change score (p=0.06). Thus, telomere length may serve as a biomarker for cognitive aging.
Cognitive Decline; Biomarker; Genetics; Telomeres; Epidemiology