Population-based Study Of Older Adults Research Articles

Blood Lead Is a Predictor of Homocysteine Levels in a Population-Based Study of Older Adults

Lead and homocysteine are both associated with cardiovascular disease and cognitive dysfunction. We evaluated the relations among blood lead, tibia lead, and homocysteine levels by cross-sectional analysis of data among subjects in the Baltimore Memory Study, a longitudinal study of 1,140 randomly selected residents in Baltimore, Maryland, who were 50–70 years of age. Tibia lead was measured by 109Cd K-shell X-ray fluorescence. The subject population had a mean ± SD age of 59.3 ± 5.9 years and was 66.0% female, 53.9% white, and 41.4% black or African American. Mean ± SD blood lead, tibia lead, and homocysteine levels were 3.5 ± 2.4 μg/dL, 18.9 ± 12.5 μg/g, and 10.0 ± 4.1 μmol/L, respectively. In unadjusted analysis, blood lead and homocysteine were moderately correlated (Pearson’s r = 0.27, p < 0.01). After adjustment for age, sex, race/ethnicity, educational level, tobacco and alcohol consumption, and body mass index using multiple linear regression, results revealed that homocysteine levels increased 0.35 μmol/L per 1.0 μg/dL increase in blood lead (p < 0.01). The relations of blood lead with homocysteine levels did not differ in subgroups distinguished by age, sex, or race/ethnicity. Tibia lead was modestly correlated with blood lead (Pearson’s r = 0.12, p < 0.01) but was not associated with homocysteine levels. To our knowledge, these are the first data to reveal an association between blood lead and homocysteine. These results suggest that homocysteine could be a mechanism that underlies the effects of lead on the cardiovascular and central nervous systems, possibly offering new targets for intervention to prevent the long-term consequences of lead exposure.

The Association Between Health and Cognitive Performance in a Population-Based Study of Older Adults: The Charlotte County Healthy Aging Study (CCHAS)

In the present study, the relationship between self-reports and objective measures of health status and measures of cognitive performance was examined. Participants consisted of 437 persons (M =72.91 years) from the Charlotte County Healthy Aging Study, a population-based sample of older adults. Cognitive performance was assessed by tests of episodic memory, perceptual speed, and attention. Health status was indexed by subjective ratings, self-reports, and objective measures. The health measures accounted for significant variance on both the Trailmaking A and B tests, accounting for a modest amount of variance (4.4% and 1.1%, respectively). The health measures were not significantly associated with performance on the measures of attention or episodic memory. The results suggest that health status is associated with processing speed to a greater degree than higher order cognitive processes.

Sexual assault and physical health: findings from a population-based study of older adults.

Prior reports have pointed to an adverse effect of sexual assault on subsequent health, particularly depression and obesity, in women. The objective of this study was to determine whether there is an association between self-reported sexual assault history and objective parameters of physical health in a sample of older men and women. We conducted a cross-sectional study of white, middle to upper middle class, older (median age 75 years) men (N = 533) and women (N = 826) within a defined community setting. Sex-specific, age-adjusted risks were calculated for 11 common chronic medical conditions (10 for each sex: coronary heart disease, hypertension, diabetes, osteoporosis, obesity, asthma, migraine, thyroid disease, and arthritis in all subjects; breast cancer in women; and prostate cancer in men) and confirmed by physical or laboratory examination or review of medical records. Sexual assault was reported by 5.4% of men and 12.7% of women; repeated exposure was reported by 10.3 and 21.9% of sexually assaulted men and women, respectively. In women, a history of sexual assault was associated with an increased risk of 2 of 10 conditions: arthritis (OR = 1.76, 95% CI = 1.13-2.76) and breast cancer (OR = 2.21, 95% CI = 1.12-4.33). A "dose-response" effect was observed: Multiple episodes of sexual assault carried a two- to three-fold increased risk of these diseases compared with a single episode. In men, the only statistically significant association was between sexual assault and thyroid disease (OR = 4.68, 95% CI = 1.08-20.3). These data partially replicate findings from other studies of adverse effects of sexual trauma on health, although the specific diseases are different. Causal mechanisms cannot be inferred from these data. Studies in other cohorts are warranted.

Sex differences in the prevalence of mobility disability in old age: the dynamics of incidence, recovery, and mortality.

This study examined sex differences in the prevalence of mobility disability in older adults according to the influences of three components of prevalence: disability incidence, recovery from disability, and mortality. Participants in a population-based study of older adults from three communities in the United States (N = 10,263) were studied for up to 7 years. Life table methods were used to estimate the influence of each of the three components of disability prevalence in women and men. Sex differences in probabilities for transition states were measured by relative risks derived from a single model using a Markov chain approach. The proportion of disabled women increased from 22% of women aged 70 years to 81% of those aged 90 years. In men, comparable figures were 15% and 57%. Incidence had the greatest impact on the sex differences in disability prevalence until age 90 and older when recovery rates had a greater impact on differences in prevalence. Mortality differences in men and women had only a modest impact on sex differences in disability prevalence. These findings initially seemed to contradict striking sex differences observed in the relative risks for mortality in men compared with women. Subsequent graphical analyses showed that incidence rather than recovery or mortality largely accounted for sex differences in disability prevalence in old age. Disability incidence, recovery from disability, and mortality dynamically influence the sex differences in the prevalence of mobility disability. However, incidence has the greatest impact overall on the higher prevalence of disability in women compared with men.

Risk Factors for 30-Day Mortality in Elderly Patients With Lower Respiratory Tract Infection

Pneumonia is a major cause of death in the elderly, but there are few studies of risk factors for death that include both ambulatory and nursing home patients. To assess factors associated with 30-day mortality in a population-based study of older adults with lower respiratory tract infection. Identification of (1) a previously identified retrospective cohort of all residents of Rochester, Minn, aged 65 years or older who experienced a first episode of pneumonia or bronchitis during a calendar year and (2) the risk factors associated with 30-day mortality through review of complete inpatient and ambulatory medical records. Logistic regression was used to identify significant independent risk factors for 30-day mortality. A total of 413 adults aged 65 years or older were identified. The independent factors for 30-day mortality were atypical symptoms (odds ratio [OR], 4.98; 95% confidence interval [CI], 2.14-11.60), neurologic illness (OR, 3.92; 95% CI, 1.47-6.59), current diagnosis of cancer (OR, 6.2; 95% CI, 2.40-15.99), and recent or current use of antibiotics (OR, 3.13; 95% CI, 1.45-6.77). Malignancy and neurologic disease are well-recognized conditions that identify patients with lower respiratory tract infections who have a high risk of death within 30 days. An atypical presentation with confusion, lethargy, poor eating, or recent or current antibiotic use also identifies patients, with a high risk of 30-day mortality.

Urinary N-Telopeptide Levels Discriminate Normal, Osteopenic, and Osteoporotic Bone Mineral Density

The level of urinary, type I collagen, crosslinked N-telopeptides (NTX) is a new marker of bone resorption. To our knowledge, no population-based studies of older adults have determined whether this measure can identify individuals with osteoporosis. To measure the levels of NTX in a cross-sectional study of ambulatory, older, white adults and to evaluate whether this measure of bone resorption could identify individuals with osteoporosis. The subjects, aged 50 to 98 years, formed 3 groups: 374 men, 223 women currently using estrogen, and 364 women not currently using estrogen. A standard medical history and validated record of medication use were obtained. Height and weight were measured. Bone mineral density (BMD) was measured at the hip and lumbar spine using dual energy x-ray absorptiometry. The levels of NTX were measured by enzyme-linked immunosorbent assay. Overall, the levels of NTX increased slightly with age in men and in estrogen users and more dramatically in nonestrogen users. In a model adjusted for all major risk factors for osteoporosis, there was a significant decrease in BMD levels by increasing quintiles of NTX levels at the hip and spine in women with and without estrogen use and at the hip in men. Using sex-specific, peak bone mass criteria and age-adjusted analyses, the levels of NTX discriminated between normal (< or = -1.0 SD), osteopenic (> -1.0 and < -2.5 SD), and osteoporotic (> or = -2.5 SD) BMD levels in all groups except the spine in men. The levels of NTX uniquely discriminated between older adults with normal, osteopenic, or osteoporotic BMD levels. If confirmed, these data suggest that NTX levels could be used to predict current osteoporosis in older men and women.

Relation of smoking with carotid artery wall thickness and stenosis in older adults. The Cardiovascular Health Study. The Cardiovascular Health Study (CHS) Collaborative Research Group.

Cigarette smoking has been associated with increased risk of atherosclerotic diseases in hospital-based studies and in studies of middle-aged populations but not in population-based studies of older adults with and without clinical cardiovascular disease. We investigated the relation of smoking to carotid artery atherosclerotic disease, expressed as intimal-medial wall thickness and arterial lumen narrowing (stenosis) measured by ultrasound. Subjects were 5116 older adults participating in the baseline examination of the Cardiovascular Health Study, a community-based study of cardiovascular diseases in older age. With increased smoking there was significantly greater internal and common carotid wall thickening and internal carotid stenosis: current smokers > former smokers > never-smokers; for instance, the unadjusted percent stenosis was 24%, 20%, and 16%, respectively (P < .0001). A significant dose-response relation was seen with pack-years of smoking. These findings persisted after adjusting for other cardiovascular risk factors and were also confirmed when analyses were restricted to those without prevalent cardiovascular disease. The difference in internal carotid wall thickness between current smokers and nonsmokers was greater than the difference associated with 10 years of age among never-smoking participants (0.39 mm versus 0.31 mm). Among all participants, the prevalence of clinically significant (> or = 50%) internal carotid stenosis increased from 4.4% in never-smokers to 7.3% in former smokers to 9.5% in current smokers (P < .0001). These findings extend previous reports of a positive relation between smoking and carotid artery disease to a population-based sample of older adults using several different indicators of atherosclerotic disease.