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Biomedical subjects

C A Macera

Publications and source records attributed to C A Macera.

At least 37 records · Page 2Linked to original sources
PubMed1999

Association between exercise and HIV disease progression in a cohort of homosexual men.

PURPOSE: To study the relationship between exercise and human immunodeficiency virus (HIV) disease progression. METHODS: 415 individuals (156 HIV positive, 259 HIV negative), from a cohort study of 851 homosexual men from New York City, 1985-1991. By 1991, 68 of the 156 persons developed Acquired Immune Deficiency Syndrome (AIDS) and 49 died with AIDS. Exercise was defined as self-report of exercising 3-4 times/week or daily at entry; less was considered nonexercise. CD4 lymphocyte decline was constructed for each subject by modeling log CD4 count against time in days. The association between exercise and progression to AIDS and death with AIDS, adjusting for baseline CD4 count, was determined using Cox model. Linear regression was used to model CD4 decline with exercise for HIV positive and HIV negative groups separately, adjusting for initial CD4 count. RESULTS: Having exercised was associated with slower progression to AIDS at 1 year (HR = 0.68, 90% confidence interval (CI): 0.4-1.17); hazard ratios (HR) at 2, 3, and 4 years were 0.96, 1.18, and 1.36, respectively. Having exercised was also associated with slower progression to death with AIDS at 1 year (HR = 0.37, 90% CI: 0.14-0.94) with hazard ratios at 2, 3, and 4 years of 0.68, 0.98, and 1.27, respectively, suggesting a protective effect close to the time exercise was assessed, but an increased risk after 2 years. Exercising 3-4 times/week had a more protective effect than daily exercise. Exercisers in the HIV positive group showed an increase in CD4 count during a year by a factor of 1.07. CONCLUSION: Moderate physical activity may slow HIV disease progression.

Acquired Immunodeficiency Syndrome↗
PubMed1999

The value of strength training for older adults.

Health in older adults can best be measured in terms of functional status. Skeletal muscle strength has been reported to be a determinant of functional status in older individuals. Two major contributors to the decline in muscle function as a person ages are disuse and physical inactivity. Declining muscle function through a loss of muscular strength may decrease functional independence and mobility and increase the risk for falls and injuries, physical frailty, and disability. Older individuals lacking an appropriate amount of muscular strength may not be able to perform various activities of daily living, which are important indicators of independence.

Activities of Daily Living↗
PubMed1999

Levels of physical activity and inactivity in children and adults in the United States: current evidence and research issues.

PURPOSE: The purpose was to describe current levels of physical activity and inactivity among adults and young people in the United States. METHODS: Estimates of participation in regular physical activity were derived from three national surveys for adults (National Health Interview Survey, National Health and Nutrition Examination Survey, and the Behavioral Risk Factor Surveillance System) and from the Youth Risk Behavior Survey for high school students. RESULTS: Overall, 63.8% of high school students surveyed on the 1997 YRBS reported participating in vigorous physical activity for at least 20 min on 3 or more days per week. Participation in vigorous activity was higher for boys (72.3%) than girls (53.5%), whites (66.8%) compared with blacks (53.9%) and Hispanics (60.4%), and decreased with advancing grade. Among adults, 27.7% meet recommended levels of either moderate or vigorous physical activity, whereas 29.2% report no regular physical activity outside of their work. Gender differences in participation in physical activity are less pronounced than in youth, and age-related patterns were complex. Whites are more active than blacks and Hispanics, and persons with higher family incomes and more education report being more physically active. There have been only minor changes in reported participation in leisure time physical activity over the past 15 yr. CONCLUSION: National estimates of physical activity appear to be reliable and valid for adults but may be less so for adolescents and are poor measures for children. Research is needed to determine the role that objective monitoring with accelerometers may play in surveillance. Reliable and valid measures of occupational, household, and transportation-related physical activity and sedentary behaviors are needed to better characterize the range of activity that is associated with health.

Adult↗
PubMed1998

Exaggerated blood pressure response to dynamic exercise and risk of future hypertension.

This study examined the association between an exaggerated blood pressure response to treadmill exercise and the risk of developing hypertension. Subjects were healthy normotensive men (n = 5386) who had a baseline graded maximal exercise test between 1971 and 1982, and completed a mailed follow-up questionnaire. At follow-up in 1986, cases (n = 151) reported physician diagnosed hypertension and controls (n = 201) reported normotension. Those who had developed hypertension at follow-up were more likely to have had an exaggerated blood pressure response to exercise (OR = 2.4, 1.4-4.3). In multiple logistic regression analysis an exaggerated response was significantly associated (OR = 3.0, 1.5-6.1) with future hypertension after controlling for sitting systolic and diastolic blood pressure, weight change from age 21 to follow-up, entry age, family history of hypertension, body mass index, treadmill time, alcohol consumption, and years of follow-up. These results suggest that an exaggerated blood pressure response to exercise is independently associated with increased risk of future hypertension, and therefore, may be an important factor in determining hypertension risk.

Adult↗
PubMed1998

Influences of cardiorespiratory fitness levels and other predictors on cardiovascular disease mortality in men.

PURPOSE: This investigation quantifies the relation between cardiorespiratory fitness levels and cardiovascular disease (CVD) mortality within strata of other CVD predictors. METHODS: Participants included 25,341 male Cooper Clinic patients who underwent a maximal graded exercise test. CVD death rates were determined for low (least fit one-fifth), moderate (next two-fifths), and high (top two-fifths) cardiorespiratory fitness categories by strata of smoking habit, blood cholesterol level, resting blood pressure, and health status. There were 226 cardiovascular deaths during 211,996 man-years of follow-up. RESULTS: For individuals with none of the major CVD predictors (smoking, elevated resting systolic blood pressure, elevated blood cholesterol), there was a strong inverse relation (P = 0.001) between fitness level and CVD mortality. An inverse relation between CVD mortality and fitness level was seen within strata of cholesterol levels and health status. No evidence of a trend (P = 0.60) for decreased mortality was seen across fitness levels for individuals with elevated systolic blood pressure; however, a strong inverse gradient (P < 0.001) was seen across fitness levels for individuals with normal systolic blood pressure. There was a tendency for association between high levels of fitness and decreased CVD mortality in smokers compared with low and moderately fit smokers (P < 0.076). There was no significant association between level of fitness and CVD mortality for individuals with multiple (two or more) predictors (P = 0.325). Approximately 20% of the 226 CVD deaths in the population studied were attributed to low fitness level. CONCLUSIONS: Moderate and high levels of cardiorespiratory fitness seem to provide some protection from CVD mortality, even in the presence of well established CVD predictors.

Adult↗
PubMed1998

Physical fitness, physical activity, and functional limitation in adults aged 40 and older.

PURPOSE: A cohort of middle-aged and older men and women were followed for an average of 5.5 yr to examine the association between physical fitness, physical activity, and the prevalence of functional limitation. METHODS: The participants received medical assessments between 1980 and 1988 and responded to a mail-back survey regarding functional status in 1990. RESULTS: Among 3495 men and 1175 women over 40 yr of age at baseline, 350 (7.5%) reported at least one functional limitation in daily or household activities at follow-up. The prevalence of functional limitation was higher among women than men. Physically fit and physically active participants reported less functional limitation than unfit or sedentary participants. After controlling for age and other risk factors, the prevalence of functional limitation was lower for both moderately fit (odds ratio = 0.4, 95% CI = 0.2-0.6) and high fit men (odds ratio = 0.3, 95% CI = 0.2-0.4), compared with low fit men. Corresponding figures for women were 0.5 (0.3-0.7) and 0.3 (0.2-0.5) for moderately fit and high fit women. The association between physical activity and functional limitation was similar to the data for physical fitness. CONCLUSIONS: These data support a protective effect of physical fitness and physical activity on functional limitation among older adults and extend this protective effect to middle-aged men and women.

Adult↗
PubMed1997

Functional health status as a predictor of mortality in men and women over 65.

This study evaluated the effect of functional health status on mortality in a sample of community-dwelling older people. White and African-American self-respondents to the 1986 National Health Interview Survey Functional Health Supplement (n = 5, 320) were included in the study. Functional health status was measured by a ten-item unidimensional activities of daily living-instrumental activities of daily living (ADL-IADL) scale and a three-item cognitive ADL scale. Proportional hazards regression was used to evaluate the effect of increasing score on the ten-item ADL-IADL scale on risk of mortality over a 5-year period while controlling for demographic, social, and health status covariates. In both men and women, increasing score on the ADL-IADL scale was predictive of mortality, adjusting for increasing age, poor self-rated health, low body mass index in women, and being an unmarried man. These findings indicate that a unidimensional scale consisting of both ADL and IADL items is useful in predicting mortality, controlling for the effect of covariates in sex-specific models.

Activities of Daily Living↗
PubMed1997

Changes in lipids associated with change in regular exercise in free-living men.

OBJECTIVE: To investigate the relationship between regular exercise and plasma lipid profiles in free-living men. METHODS: Seven hundred eighty men between the ages of 25 and 65 years were included in this study. The medical history, physical examination, and blood tests were obtained at baseline and 1 year later. At the end of the study, 430 (55.1%) men reported the same amount of regular exercise as a year earlier; 199 (25.5%) men reported an increased level, and 151 (19.4%) men reported a decreased level. RESULTS: Compared to the group with same exercise, men who increased their level of regular exercise had a significant increase in high-density lipoprotein cholesterol (HDLC) (mean 4.76 versus 2.83 mg/dL, p < 0.005) and significant decreases in the ratio of total cholesterol/HDLC (mean -0.72 versus -0.42, p < 0.001) and triglycerides (mean -18.2 versus -6.27 mg/dL, p < 0.001). The changes in lipid profiles appeared to have a dose-response relationship from the increased exercise, same exercise, to decreased exercise groups. Overweight and normal-weight men had a similar tendency to improve their lipid profiles by exercise. The improvement in plasma lipid profile associated with increased regular exercise persisted after controlling for potential confounders. CONCLUSIONS: The results indicate that the relationship between physical activity and favorable lipid profiles exists in men with mild-to-moderate physical activity.

Adult↗
PubMed1997

Major depression and all-cause mortality among white adults in the United States.

PURPOSE: Depression is the most common psychiatric illness affecting adults. Despite the importance of a potential link between major depression and mortality, research has been surprisingly sparse. METHODS: Information on 57,897 white adults aged 25 years and older who were included in the mental health supplement of the 1989 National Health Interview Survey was linked with the National Death Index to examine the relationship of major depression to mortality. Death status was obtained through December 1991. Sex-specific hazard rate ratios for mortality were calculated by Cox proportional hazards regression and Poisson regression to adjust for potential confounders (age, education, marital status, body mass index, and whether the target subject or a family member completed the survey about the subject). RESULTS: Major depression was reported for 223 (0.8%) of 27,345 men and 392 (1.3%) of 30,552 women. During the 2.5-year follow-up, death certificate data were obtained for 848 (3.1%) men and 651 (2.1%) women. The adjusted hazard rate ratios for all-cause mortality associated with major depression were 3.1 (95% confidence interval; 2.0-4.9) for men and 1.7 (95% confidence interval; 0.9-3.1) for women. CONCLUSIONS: These results suggest that major depression increases risk of all-cause mortality, particularly among men. Further research is needed to explain the mechanism.

Adult↗
PubMed1997

The impact of a required college health and physical education course on the health status of alumni.

The impact of a required college health and physical education course on selected health knowledge, attitudes, and behaviors of alumni was evaluated. The design was a cross-sectional study (mail out/mail back survey) using a stratified random sample of 2,000 college alumni. The overall response rate was 50%. Results were analyzed by college of graduation (college with a required health/physical education course versus no required course). Alumni who took the course were more likely to know their blood pressure, blood cholesterol, and recommended dietary fat intake than the comparison group were. They also reported that the course positively influenced their attitudes toward exercise, eating, and smoking They were more likely to engage in aerobic exercise and less likely to smoke; and they had lower intakes of dietary fat, cholesterol, and sodium. The results suggested that a required college course enhanced selected health-related knowledge, attitudes, and behaviors of alumni.

Adult↗
PubMed1997

Effect of body mass index on activity limitation and mortality among older women: the National Health Interview Survey, 1986-1990.

We assessed the impact of body mass on the association between activity limitations due to chronic conditions and mortality among 24,612 noninstitutionalized white or African American women aged > or = 65 years who participated in a National Health Interview Survey between 1986 and 1990. We found that more African American women had activity limitations than white women (59% vs 46%, respectively). The difference by race was greatest (19% vs 10%) for the most severe limitation (unable to perform the major activity). For women aged 65-69, the major activity was working or keeping house; for those aged > or = 70, it was the ability to live independently. For white women in all three categories of body mass index (BMI) and for African American women with BMI 15%-85%, the risk of dying was significantly higher for those unable to perform the major activity than for those with no limitations, controlling for the effects of education, marital status, and perceived health. The findings confirm the established link between low BMI and mortality and between activity limitations and mortality. Additionally, the findings further suggest that activity limitations linked to chronic conditions increase the risk of death within each stratum of BMI after adjusting for potential confounders.

Activities of Daily Living↗
PubMed1997

Risk of institutionalization among community long-term care clients with dementia.

South Carolina Community Long-Term Care (CLTC) data were used to identify factors increasing the risk of institutionalization in people with dementia. Clients diagnosed with dementia and observed at least twice between June 1993 and December 1994 (N = 786) were studied. Logistic regression determined that clients with a decline in ADL function who were white, had a nonrelative or child as a caregiver, and were diagnosed with Alzheimer's disease were at increased risk of institutionalization. Identifying CLTC clients at increased risk of institutionalization could be useful in designing additional interventions to prevent institutionalization or in planning the transition to institutional care.

Activities of Daily Living↗
PubMed1997

Survival after AIDS diagnosis in South Carolina, 1982-1992.

The results of this study demonstrate that age, ethnicity, and AIDS-defining diagnosis are important predictors of survival time after AIDS diagnosis, and should be considered when planning treatment and services for people with AIDS. Future studies in states with large rural populations will be helpful in further understanding the natural history of the disease in areas outside the nation's major population centers. These could improve on the results of the present study by actively following up all cases to determine mortality status, collecting detailed clinical information on AIDS-defining diagnoses (with dates), collecting information on treatment of HIV infection and associated opportunistic infections, and evaluating service utilization. Monitoring survival trends over time remains an effective tool in evaluating the success of current efforts to provide treatment and services to people with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Self-reported prevalence of diabetes and preventive health care practices among people with diabetes in South Carolina.

In conclusion, South Carolina has a higher prevalence of diabetes compared to the national average. Age is a major factor associated with increased prevalence. African Americans had a disproportionately higher prevalence of diabetes relative to white Americans in South Carolina. Compared to the standards of diabetes care recommended by the ADA, health care practice by people with diabetes and health professionals still needs to be improved. Diabetes communication programs, including diabetes education for people with diabetes and health professional education, continue to be necessary for the improvement of diabetes care.

Adolescent↗
PubMed1997

Body fat distribution and race differences in apolipoprotein A1.

OBJECTIVE: This is the first study to assess the role of waist-to-hip ratio in explaining race differences in levels of serum apolipoprotein A1, a protective risk factor for atherosclerosis. METHODS: Linear regression analyses were used in a community-based survey of 3,043 adults (23.5% African-American) to assess associations of race, age, anthropometric measures, education, diabetes, blood pressure medication use, cigarette smoking, and leisure-time physical activity with apolipoprotein A1 levels. RESULTS: Higher apolipoprotein A1 levels were observed among African-American than among white adults (African-American men: +15.6 mg/dl than white men, African-American women: +3.1 mg/dl more than white women; p < 0.05). Waist-to-hip ratio and other variables did not account for race differences among men. African-American women had +8.6 mg/dl higher levels than white women after adjustment for differing distributions of waist-to-hip ratio, age, body mass index and education. Cigarette smoking, physical activity, and medical history accounted for no further differences among women. CONCLUSIONS: Higher levels of obesity indicators and lower educational attainment among African-American women reduced a potentially greater beneficial race difference in apolipoprotein A1. These findings also suggest that other environmental and biochemical factors may play roles in explaining the higher protective levels of apolipoprotein A1 observed among African-American children and adults.

Adipose Tissue↗
PubMed1996

Influences of cardiorespiratory fitness and other precursors on cardiovascular disease and all-cause mortality in men and women.

OBJECTIVE: To quantify the relation of cardiorespiratory fitness to cardiovascular disease (CVD) mortality and to all-cause mortality within strata of other personal characteristics that predispose to early mortality. DESIGN--Observational cohort study. We calculated CVD and all-cause death rates for low (least fit 20%), moderate (next 40%), and high (most fit 40%) fitness categories by strata of smoking habit, cholesterol level, blood pressure, and health status. SETTING: Preventive medicine clinic. STUDY PARTICIPANTS: Participants were 25341 men and 7080 women who completed preventive medical examinations, including a maximal exercise test. MAIN OUTCOME MEASURES: Cardiovascular disease and all-cause mortality. RESULTS: There were 601 deaths during 211996 man-years of follow-up, and 89 deaths during 52982 woman-years of follow-up. Independent predictors of mortality among men, with adjusted relative risks (RRs) and 95% confidence intervals (CIs), were low fitness (RR, 1.52;95% CI, 1.28-1.82), smoking (RR, 1.65; 95% CI, 1.39-1.97), abnormal electrocardiogram (RR, 1.64;95% CI, 1.34-2.01), chronic illness (RR, 1.63;95% CI, 1.37-1.95), increased cholesterol level (RR, 1.34; 95% CI, 1.13-1.59), and elevated systolic blood pressure (RR, 1.34; 95% CI, 1.13-1.59). The only statistically significant independent predictors of mortality in women were low fitness (RR, 2.10; 95% Cl, 1.36-3.21) and smoking (RR, 1.99; 95% Cl, 1.25-3.17). Inverse gradients were seen for mortality across fitness categories within strata of other mortality predictors for both sexes. Fit persons with any combination of smoking, elevated blood pressure, or elevated cholesterol level had lower adjusted death rates than low-fit persons with none of these characteristics. CONCLUSIONS: Low fitness is an important precursor of mortality. The protective effect of fitness held for smokers and nonsmokers, those with and without elevated cholesterol levels or elevated blood pressure, and unhealthy and healthy persons. Moderate fitness seems to protect against the influence of these other predictors on mortality. Physicians should encourage sedentary patients to become physically active and thereby reduce the risk of premature mortality.

Adult↗