Chronic inflammation and risk of colorectal and other obesity-related cancers: The health, aging and body composition study.

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 2,490 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.

Unhealthy lifestyles do not mediate the relationship between socioeconomic status and incident depressive symptoms: the Health ABC study.

BACKGROUND: The relationship between low socioeconomic status (SES) and depressive symptoms is well described, also in older persons. Although studies have found associations between low SES and unhealthy lifestyle factors, and between unhealthy lifestyle factors and depressive symptoms, not much is known about unhealthy lifestyles as a potential explanation of socioeconomic differences in depressive symptoms in older persons. METHODS: To study the independent pathways between SES (education, income, perceived income, and financial assets), lifestyle factors (smoking, alcohol use, body mass index, and physical activity), and incident depressive symptoms (Center for Epidemiologic Studies-Depression [CES-D 10] and reported use of antidepressant medication), we used 9 years of follow-up data (1997-2007) from 2,694 American black and white participants aged 70-79 years from the Health, Aging, and Body Composition (Health ABC) study. At baseline, 12.1% of the study population showed prevalent depressive symptoms, use of antidepressant medication, or treatment of depression in the 5 years prior to baseline. These persons were excluded from the analyses. RESULTS: Over a period of 9 years time, 860 participants (31.9%) developed depressive symptoms. Adjusted hazard ratios for incident depressive symptoms were higher in participants from lower SES groups compared with the highest SES group. The strongest relationships were found for black men. Although unhealthy lifestyle factors were consistently associated with low SES, they were weakly related to incident depressive symptoms. Lifestyle factors did not significantly reduce hazard ratios for depressive symptoms by SES. CONCLUSION: In generally healthy persons aged 70-79 years, lifestyle factors do not explain the relationship between SES and depressive symptoms.

Racial differences in mortality in older adults: factors beyond socioeconomic status.

BACKGROUND: Little is known about the simultaneous effect of socioeconomic status (SES), psychosocial, and health-related factors on race differences in mortality in older adults. PURPOSE: This study examined the association between race and mortality and the role of SES, health insurance, psychosocial factors, behavioral factors, and health-related factors in explaining these differences. METHODS: Data consisted of 2,938 adults participating in the Health, Aging and Body Composition study. Mortality was assessed over 8 years. RESULTS: SES differences accounted for 60% of the racial differences in all-cause mortality; behavioral factors and self-rated health further reduced the disparity. The racial differences in coronary heart disease mortality were completely explained by SES. Health insurance and behavioral factors accounted for some, but not all, of the race differences in cancer mortality. CONCLUSIONS: Race-related risk factors for mortality may differ by the underlying cause of mortality.

Late-life depressed mood and weight change contribute to the risk of each other.

OBJECTIVE: Weight change may be considered an effect of depression. In turn, depression may follow weight change. Deteriorations in health may mediate these associations. The objective was to examine reciprocal associations between depressed mood and weight change, and the potentially mediating role of deteriorations in health (interim hospitalizations and incident mobility imitation) in these associations. METHODS: Data were from 2406 black and white men and women, aged 70-79 from Pittsburgh, Pennsylvania and Memphis, Tennessee participating in the Health, Aging and Body composition (Health ABC) study. Depressed mood at baseline (T1) and 3-year follow-up (T4) was measured with the CES-D scale. Three weight change groups (T1-T4) were created: loss (>or=5% loss), stable (within +/-5% loss or gain), and weight gain (>or=5% gain). RESULTS: At T1 and T4, respectively 4.4% and 9.5% of the analysis sample had depressed mood. T1 depressed mood was associated with weight gain over the 3-year period (OR:1.91; 95%CI:1.13-3.22). Weight loss over the 3-year period was associated with T4 depressed mood (OR:1.51; 95%CI:1.05-2.16). Accounting for deteriorations in health in the reciprocal associations between weight change and depressed mood reduced effect sizes between 16-27%. CONCLUSIONS: In this study, depressed mood predicted weight gain over three years, while weight loss over three years predicted depressed mood. These associations were partly mediated through deteriorations in health. Implications for clinical practice and prevention include increased awareness that depressed mood can cause weight change, but can also be preceded by deteriorations in health and weight change.

Overweight and obesity over the adult life course and incident mobility limitation in older adults: the health, aging and body composition study.

Obesity in middle and old age predicts mobility limitation; however, the cumulative effect of overweight and/or obesity over the adult life course is unknown. The association between overweight and/or obesity in young, middle, and late adulthood and its cumulative effect on incident mobility limitation was examined among community-dwelling US adults aged 70-79 years at baseline (1997-1998) in the Health, Aging and Body Composition Study (n = 2,845). Body mass index was calculated by using recalled weight at ages 25 and 50 years and measured weight at ages 70-79 years. Mobility limitation (difficulty walking 1/4 mile (0.4 km) or climbing 10 steps) was assessed semiannually over 7 years of follow-up and was reported by 43.0% of men and 53.7% of women. Men and women who were overweight or obese at all 3 time points had an increased risk of mobility limitation (hazard ratio = 1.61, 95% confidence interval: 1.25, 2.06 and hazard ratio = 2.85, 95% confidence interval: 2.15, 3.78, respectively) compared with those who were normal weight throughout. Furthermore, there was a significant graded response (P < 0.0001) on risk of mobility limitation for the cumulative effect of obesity in men and overweight and/or obesity in women. Onset of overweight and obesity in earlier life contributes to an increased risk of mobility limitation in old age.

Posttraumatic stress disorder in migraine.

OBJECTIVE: To evaluate the relative frequency of posttraumatic stress disorder (PTSD) in episodic migraine (EM) and chronic daily headache (CDH) sufferers and the impact on headache-related disability. BACKGROUND: Approximately 8% of the population is estimated to have PTSD. Recent studies suggest a higher frequency of PTSD in headache disorders. The association of PTSD and headache-related disability has not been examined. METHODS: A prospective study was conducted at 6 headache centers. PTSD was assessed using the life events checklist and PTSD checklist, civilian version (PCL-C). We compared data from EM to CDH, and migraine with PTSD to migraine without PTSD. The PHQ-9 was used to assess depression, and headache impact test (HIT-6) to assess disability. RESULTS: Of 767 participants, 593 fulfilled criteria for EM or CDH and were used in this analysis. The mean age was 42.2 years and 92% were women. The frequency of PTSD was greater in CDH than in EM (30.3% vs 22.4%, P = .043), but not after adjusting for demographics and depression (P = .87). However, participants with major depression and PTSD were more likely to have CDH than EM (24.6% vs 15.79%, P < .002). Disability was greater in migraineurs with PTSD, even after adjustments (65.2 vs 61.7, P = .002). CONCLUSION: The frequency of PTSD in migraineurs, whether episodic or chronic, is higher than the historically reported prevalence of PTSD in the general population. In addition, in the subset of migraineurs with depression, PTSD frequency is greater in CDH sufferers than in episodic migraineurs. Finally, the presence of PTSD is independently associated with greater headache-related disability in migraineurs.

Association between nighttime sleep and napping in older adults.

STUDY OBJECTIVES: Napping might indicate deficiencies in nighttime sleep, but the relationship is not well defined. We assessed the association of nighttime sleep duration and fragmentation with subsequent daytime sleep. DESIGN: Cross-sectional study. PARTICIPANTS: 235 individuals (47.5% men, 29.7% black), age 80.1 (2.9) years. MEASUREMENTS AND RESULTS: Nighttime and daytime sleep were measured with wrist actigraphy and sleep diaries for an average of 6.8 (SD 0.7) nights. Sleep parameters included total nighttime sleep (h), movement and fragmentation index (fragmentation), and total daytime sleep (h). The relationship of total nighttime sleep and fragmentation to napping (yes/no) was assessed using logistic regression. In individuals who napped, mixed random effects models were used to determine the association between the previous night sleep duration and fragmentation and nap duration, and nap duration and subsequent night sleep duration. All models were adjusted for age, race, gender, BMI, cognitive status, depression, cardiovascular disease, respiratory symptoms, diabetes, pain, fatigue, and sleep medication use. Naps were recorded in sleep diaries by 178 (75.7%) participants. The odds ratios (95% CI) for napping were higher for individuals with higher levels of nighttime fragmentation (2.1 [0.8, 5.7]), respiratory symptoms (2.4 [1.1, 5.4]), diabetes (6.1 [1.2, 30.7]), and pain (2.2 [1.0, 4.7]). Among nappers, neither sleep duration nor fragmentation the preceding night was associated with nap duration the next day. CONCLUSION: More sleep fragmentation was associated with higher odds of napping although not with nap duration. Further research is needed to determine the causal association between sleep fragmentation and daytime napping.

Sleep problems and associated daytime fatigue in community-dwelling older individuals.

BACKGROUND: Reported fatigue has been identified as a component of frailty. The contribution of nighttime sleep quality (duration and complaints) to fatigue symptoms in community-dwelling older adults has not been evaluated. METHODS: We studied 2264 men and women, aged 75-84 years (mean 77.5 years; standard deviation [SD] 2.9), participating in the Year 5 (2001--2002) clinic visit of the Health, Aging, and Body Composition (Health ABC) study. Fatigue was determined using a subscale of the Modified Piper Fatigue Scale (0-50; higher score indicating higher fatigue). Hours of sleep per night, trouble falling asleep, waking up during the night, and waking up too early in the morning were assessed using interviewer-administered questionnaires. RESULTS: The average fatigue score was 17.7 (SD 8.4). In multivariate models, women had a 3.8% higher fatigue score than men did. Individuals who slept < or = 6 hours/night had a 4.3% higher fatigue score than did those who slept 7 hours/night. Individuals with complaints of awakening too early in the morning had a 5.5% higher fatigue score than did those without these complaints. These associations remained significant after multivariate adjustment for multiple medical conditions. CONCLUSION: The association between self-reported short sleep duration (< or = 6 hours), and waking up too early and fatigue symptoms suggests that better and more effective management of sleep behaviors may help reduce fatigue in older adults.

A drug burden index to define the functional burden of medications in older people.

BACKGROUND: Older people carry a high burden of illness for which medications are indicated, along with increased risk of adverse drug reactions. We developed an index to determine drug burden based on pharmacologic principles. We evaluated the relationship of this index to physical and cognitive performance apart from disease indication. METHODS: Data from the Health, Aging, and Body Composition Study on 3075 well-functioning community-dwelling persons aged 70 to 79 years were analyzed by multiple linear regression to assess the cross-sectional association of drug burden index with a validated composite continuous measure for physical function, and with the Digit Symbol Substitution Test for cognitive performance. RESULTS: Use of anticholinergic and sedative medications was associated with poorer physical performance score (anticholinergic exposure, 2.08 vs 2.21, P<.001; sedative exposure, 2.09 vs 2.19, P<.001) and cognitive performance on the Digit Symbol Substitution Test (anticholinergic exposure, 34.5 vs 35.5, P = .045; sedative exposure, 34.0 vs 35.5, P = .01). Associations were strengthened when exposure was calculated by principles of dose response. An increase of 1 U in drug burden index was associated with a deficit of 0.15 point (P<.001) on the physical function scale and 1.5 points (P = .01) on the Digit Symbol Substitution Test. These values were more than 3 times those associated with a single comorbid illness. CONCLUSIONS: The drug burden index demonstrates that anticholinergic and sedative drug exposure is associated with poorer function in community-dwelling older people. This pharmacologic approach provides a useful evidence-based tool for assessing the functional effect of exposure to medications in this population.

Effects of birth cohort and age on body composition in a sample of community-based elderly.

BACKGROUND: The effect of the recent obesity epidemic on body composition remains unknown. Furthermore, age-related changes in body composition are still unclear. OBJECTIVE: The objective was to simultaneously examine the effects of birth cohort and age on body composition. DESIGN: A total of 1786 well-functioning, community-based whites and blacks (52% women and 35% blacks) aged 70-79 y from the Health, Aging, and Body Composition Study underwent dual-energy X-ray absorptiometry annually from 1997 to 2003. RESULTS: At baseline, mean +/- SD percentage body fat, fat mass, and lean mass (bone-free) were 28 +/- 5%, 24 +/- 7 kg, and 56 +/- 7 kg, respectively, for men and 39 +/- 6%, 28 +/- 9 kg, and 40 +/- 6 kg for women. Mixed models were used to assess the effects of cohort and age-related changes on body composition. Later cohorts in men had a greater percentage body fat (0.32% per birth year, P < 0.0001) than did earlier cohorts. This cohort effect was due to a greater increase in fat mass than in lean mass (0.45 kg and 0.17 kg/birth year, respectively). With increasing age, percentage body fat in men initially increased and then leveled off. This age-related change was due to an accelerated decrease in lean mass and an initial increase and a later decrease in fat mass. Similar but less extreme effects of cohort and age were observed in women. CONCLUSIONS: The combination of effects of both birth cohort and age leads to bigger body size and less lean mass in the elderly.

Associations between sex steroid hormone levels and depressive symptoms in elderly men and women: results from the Health ABC study.

INTRODUCTION: Sex steroid hormone levels decline with age and in some studies this decline has been linked with depressive symptoms. This study investigates the association between total testosterone, free testosterone, and DHEAS levels with depressive symptoms in a well-functioning elderly population. METHODS: Data are from 2855 well-functioning elderly men and women, 70-79 years of age, participating in the Health, Aging, and Body Composition study. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression scale. Total testosterone, free testosterone, and DHEAS levels were assessed after an overnight fast. RESULTS: In men and women, DHEAS levels and depressive symptoms were inversely associated after adjustment for covariates (men: beta=-0.059, p=0.03, women: beta=-0.054, p=0.05). In addition, free testosterone levels in women, but not in men, were inversely associated with depressive symptoms (adjusted beta=-0.079, p=0.004). Men, but not women, in the lowest total testosterone quartile reported significantly more depressive symptoms than men in the other total testosterone quartiles (adjusted beta=-0.166, p=0.04). DISCUSSION: Our study is consistent with the idea that testosterone and DHEAS levels may play a role in mechanisms underlying depressive symptoms in old age.

Anxiety symptoms and decline in physical function over 5 years in the health, aging and body composition study.

OBJECTIVES: To examine the relationship between anxiety and functional decline. DESIGN: A 5-year longitudinal cohort study of well-functioning adults. SETTING: The Health, Aging and Body Composition (Health ABC) Study. PARTICIPANTS: Two thousand nine hundred forty adults aged 70 to 79 (48% male, 41% black), initially free of self-reported mobility difficulty. MEASUREMENTS: In 1997/98, presence of three anxiety symptoms (feeling fearful, tense or keyed up, or shaky or nervous) from the Hopkins Symptom Checklist were ascertained. Physical function was examined over 5 years using the Health ABC performance battery (continuous range 0-4) consisting of chair stands, usual and narrow course gait speed, and difficulty with standing balance and self-reported mobility, defined as difficulty walking one-quarter of a mile or difficulty climbing 10 steps. RESULTS: Participants with anxiety symptoms had similar baseline physical performance scores. After adjustment for potential confounders, subjects with anxiety symptoms had similar declines in physical performance over 5 years as participants without anxiety symptoms. Adults with anxiety symptoms were more likely to report incident mobility difficulty, with a hazard ratio of 1.4 (95% confidence interval=1.3-1.6), compared with adults without anxiety symptoms. These results persisted after adjustment for depressive symptoms, demographics, comorbidity, and use of antianxiety, depressant, and sedative hypnotic medications. CONCLUSION: Anxiety symptoms are not associated with declines in objectively measured physical performance over 5 years but are associated with declines in self-reported functioning. Future studies are needed to determine why anxiety has a differential effect on performance-based and self-reported measures of functioning.

Cognitive function, gait speed decline, and comorbidities: the health, aging and body composition study.

BACKGROUND: Emerging evidence indicates an association between cognitive function and physical performance in late life. This study examines the relationship between cognitive function and subsequent gait speed decline among high-functioning older adults. METHODS: Measures of global cognitive function (Modified Mini Mental State Examination [3MS]) and executive control function (ECF) (a clock drawing task [CLOX 1] and the 15-item Executive Interview [EXIT 15]) were obtained in the Health, Aging, and Body Composition Study in 1999-2000. Gait-speed (meters/second) was assessed over 20 meters at usual pace. Using a mixed model, we assessed the relationship between baseline cognitive function and gait-speed change over 3 years. RESULTS: Two thousand, three hundred forty-nine older adults (mean age 75.6 +/- 2.9 years) completed the assessments. After adjustment for baseline gait speed, a 1-standard-deviation (SD) lower performance on each cognitive test was associated with greater gait-speed decline over 3 years: 0.016 m/s for the 3MS (SD = 8.1), 0.009 m/s for CLOX 1 (SD = 2.4), and 0.012 m/s for EXIT 15 (SD = 4.1) (p <.0005 for all). After adjustment for comorbidities, the effect size was attenuated for 3MS and CLOX 1, and the association for EXIT 15 was no longer significant. Depression score was most strongly associated with the EXIT 15 effect reduction. CONCLUSION: Global and executive cognitive functions predict declines in gait speed. The association of ECF with gait speed decline is attenuated by comorbid conditions, particularly depression. Elucidation of the mechanisms underlying these associations may point to new pathways for the treatment of physical decline associated with diminished cognitive function.

Psychosocial risk factors and the metabolic syndrome in elderly persons: findings from the Health, Aging and Body Composition study.

BACKGROUND: Psychosocial factors have been associated with metabolic abnormalities that increase the risk of cardiovascular disease and diabetes. This study investigated the cross-sectional relationship between psychosocial risk factors and the metabolic syndrome in a community-based sample of older persons. METHODS: Participants were 2917 persons aged 70-79 years enrolled in the Health, Aging and Body Composition study. Depressive and anxiety symptoms, negative life events, and inadequate emotional support were assessed, and a summary psychosocial risk index was calculated. Metabolic syndrome was defined as three or more of the following criteria: abdominal obesity, high triglycerides, low high-density lipoprotein (HDL) cholesterol, high fasting glucose, and high blood pressure. RESULTS: Negative life events and inadequate emotional support increased the odds of having metabolic syndrome after adjustment for demographic and lifestyle variables (odds ratio [OR] per life event = 1.13, 95% confidence interval [CI] = 1.05-1.22; OR = 1.35, 95% CI = 1.10-1.66, respectively). The relationship between depressive symptoms and metabolic syndrome was only found in white (OR per standard deviation [SD] = 1.11, 95% CI = 1.01-1.23), but not in black (OR per SD = 0.97, 95% CI = 0.86-1.11) persons. Anxiety symptoms were significantly associated with metabolic syndrome in men (OR per SD = 1.13, 95% CI = 1.00-1.28), but not in women (OR per SD = 0.98, 95% CI = 0.89-1.08). Moreover, a higher score on the psychosocial risk index was associated with an increased probability of having the metabolic syndrome (OR = 1.30, 95% CI = 1.12-1.52). CONCLUSIONS: In the elderly population, different psychosocial risk factors are associated with a higher prevalence of the metabolic syndrome. Whether reduction or better management of psychosocial risk factors can improve the metabolic profile remains to be demonstrated.

Association of Hearing Impairment and Anxiety in Older Adults.

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.

Are Preferences for Aggressive Medical Treatment Associated with Healthcare Utilization in the Very Old?

Objectives: To examine the relationship between end-of-life (EOL) treatment preferences and recent hospitalization or emergency department (ED) care in the very old. Design: Quarterly telephone follow-up of participants in the EOL in the Very Old cohort. Setting: The EOL in the Very Old Age cohort drew from 1403 participants in the Health, Aging, and Body Composition (Health ABC) study who were alive in year 15 of follow-up. 87.5% (n = 1227) were successfully recontacted and enrolled. Participants: Preferences for treatment at the EOL and reported hospital and ED use were examined for 1118 participants (18% involving proxy reports) over 6 months, 1021 (16% with proxy reports) over 12 months, and 945 (23% with proxy reports) over 18 months in 6-month intervals. Measurements: Preferences for eight EOL treatments, elicited once each year; hospitalization and ED use reported every six months. Results: Preferences for more aggressive treatment (endorsing ≥5 of 8 options) were not significantly associated with inpatient or ED treatment. Inpatient and ED treatment were not associated with changes in preferences for aggressive EOL treatment over 12 months. Conclusion: Alternative measures that tap attitudes toward routine care, rather than EOL treatment preferences, may be more highly associated with healthcare utilization.

Limited literacy in older people and disparities in health and healthcare access.

OBJECTIVES: To determine the relationship between health literacy, demographics, and access to health care. DESIGN: Cross-sectional study, Health, Aging and Body Composition data (1999/2000). SETTING: Memphis, Tennessee, and Pittsburgh, Pennsylvania. PARTICIPANTS: Two thousand five hundred twelve black and white community-dwelling older people who were well functioning at baseline (without functional difficulties or dementia). MEASUREMENTS: Participants' health literacy was assessed using the Rapid Estimate of Adult Literacy in Medicine. Scores were categorized into 0 to sixth-, seventh- to eighth-, and ninth-grade and higher reading levels (limited health literacy defined as <9th grade). Participants' demographics, socioeconomic status, comorbidities, and three indicators of healthcare access (whether they had a doctor/regular place of medical care, an influenza vaccination within the year, or insurance for medications) were also assessed. RESULTS: Participants' mean age was 75.6, 52% were female, 38% were black, and 24% had limited health literacy. After adjusting for sociodemographics, associations remained between limited health literacy and being male, being black, and having low income and education, diabetes mellitus, depressive symptoms, and fair/poor self-rated health (P<.02). After adjusting for sociodemographics, health status, and comorbidities, older people with a sixth-grade reading level or lower were twice as likely to have any of the three indicators of poor healthcare access (odds ratio=1.96, 95% confidence interval=1.34-2.88). CONCLUSION: Limited health literacy was prevalent and was associated with low socioeconomic status, comorbidities, and poor access to health care, suggesting that it may be an independent risk factor for health disparities in older people.

Limited literacy and mortality in the elderly: the health, aging, and body composition study.

BACKGROUND: While limited literacy is common and its prevalence increases with age, no prospective study has assessed whether limited literacy is associated with mortality in older adults. OBJECTIVE: To assess the association of limited literacy with mortality. DESIGN AND SETTING: Five-year prospective study from 1999 to 2004 of community-dwelling elders from Memphis, TN, and Pittsburgh, PA, who were from the Health, Aging, and Body Composition study. Subjects' literacy was assessed with the Rapid Estimate of Adult Literacy in Medicine. Scores were categorized into limited (0 to 8th grade reading level) or adequate literacy (> or = 9th grade reading level). PARTICIPANTS: Two thousand five hundred and twelve black and white elders without baseline functional difficulties or dementia. MEASUREMENTS: Time to death. RESULTS: Participants' mean age was 75.6 years, 48% were male, 38% were black, and 24% had limited literacy; the median follow-up time was 4.2 years. Compared with those with adequate literacy, those with limited literacy had a higher risk of death (19.7% vs 10.6%) with a hazard ratio (HR) of 2.03 (95% confidence intervals [CI], 1.62 to 2.55). After adjusting for demographics and socioeconomic status, co-morbid conditions, self-rated health status, health-related behaviors, health care access measures, and psychosocial status, limited literacy remained independently associated with mortality (HR 1.75; 95% CI, 1.27 to 2.41). CONCLUSIONS: Limited literacy is independently associated with a nearly 2-fold increase in mortality in the elderly. Given the growth of the aging population and the prevalence of chronic diseases, the mechanisms by which limited literacy is associated with mortality in the elderly warrant further investigation.

Strength, but not muscle mass, is associated with mortality in the health, aging and body composition study cohort.

BACKGROUND: Although muscle strength and mass are highly correlated, the relationship between direct measures of low muscle mass (sarcopenia) and strength in association with mortality has not been examined. METHODS: Total mortality rates were examined in the Health, Aging and Body Composition (Health ABC) Study in 2292 participants (aged 70-79 years, 51.6% women, and 38.8% black). Knee extension strength was measured with isokinetic dynamometry, grip strength with isometric dynamometry. Thigh muscle area was measured by computed tomography (CT) scan, and leg and arm lean soft tissue mass were determined by dual energy x-ray absorptiometry (DXA). Both strength and muscle size were assessed as in gender-specific Cox proportional hazards models, with age, race, comorbidities, smoking status, level of physical activity, fat area by CT or fat mass by DXA, height, and markers of inflammation, including interleukin-6, C-reactive protein, and tumor necrosis factor-alpha considered as potential confounders. RESULTS: There were 286 deaths over an average of 4.9 (standard deviation = 0.9) years of follow-up. Both quadriceps and grip strength were strongly related to mortality. For quadriceps strength (per standard deviation of 38 Nm), the crude hazard ratio for men was 1.51 (95% confidence interval, 1.28-1.79) and 1.65 (95% confidence interval, 1.19-2.30) for women. Muscle size, determined by either CT area or DXA regional lean mass, was not strongly related to mortality. In the models of quadriceps strength and mortality, adjustment for muscle area or regional lean mass only slightly attenuated the associations. Further adjustment for other factors also had minimal effect on the association of quadriceps strength with mortality. Associations of grip strength with mortality were similar. CONCLUSION: Low muscle mass did not explain the strong association of strength with mortality, demonstrating that muscle strength as a marker of muscle quality is more important than quantity in estimating mortality risk. Grip strength provided risk estimates similar to those of quadriceps strength.

Association of inflammatory markers with socioeconomic status.

BACKGROUND: This study examines the association between socioeconomic status (SES) and inflammatory markers in well-functioning older adults and seeks to determine whether any association remains after adjusting for biomedical and behavioral factors typically related to elevated serum levels of inflammatory markers. METHODS: Data were obtained from 3044 men and women, aged 70-79 from Pittsburgh, Pennsylvania and Memphis, Tennessee participating in the Health, Aging and Body Composition study. Three indicators of SES were used: education, income, and ownership of financial assets. Serum levels of interleukin-6, C-reactive protein, and tumor necrosis factor-alpha were measured. RESULTS: Low SES was associated with significantly elevated levels of interleukin-6, C-reactive protein, and tumor necrosis factor-alpha compared to high SES. Behavioral factors (including smoking, drinking, obesity) explained a substantial part of the inverse association between SES and inflammatory markers. Adjustment for prevalent diseases (including heart diseases, lung disease, and diabetes) associated with inflammation explained less of the association. CONCLUSIONS: This study suggests that interventions to improve health behaviors, even in old age and especially in low SES groups, may be useful in reducing risks associated with inflammation.