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Biomedical subjects

C A Macera

Publications and source records attributed to C A Macera.

At least 73 records · Page 4Linked to original sources
PubMed1993

Self-selected exercise intensity of habitual walkers.

This study assessed self-selected exercise intensity of habitual walkers. Twenty-nine healthy adults (22 females, 7 males; age (mean +/- SD) = 34.9 +/- 8.6 yr) performed a typical exercise walk while walking speed was measured by an unseen observer. On a subsequent occasion, the subjects walked at the same pace on a treadmill while several variables related to exercise intensity were measured. The mean self-selected walking pace was 1.78 +/- 0.19 m.s-1. Mean percents of VO2max and HRmax elicited by the treadmill exercise were 52 +/- 11% and 70 +/- 9%, respectively. Mean MET level was 5.2 +/- 1.2, and ratings of perceived exertion (RPE) averaged 10.9 +/- 1.6. Based on reported frequency and duration of walking, weekly energy expenditure in exercise walking was estimated to be 1127 +/- 783 kcal.wk-1. These data suggest that the self-selected exercise intensity of healthy, habitual exercise walkers meets the American College Sports Medicine's recommendation for improvement of cardiorespiratory fitness. These data further suggest that, in this population, the average weekly energy expended through walking reaches a level associated with improvements in health and longevity.

Adult↗
PubMed1993

Leisure-time physical activity and high-density lipoprotein cholesterol in a biracial community sample.

The purpose of this analysis was to describe the association of leisure-time physical activity and high-density lipoprotein cholesterol levels among a large community sample of African-American and white men and women. Physical assessment of high-density lipoprotein cholesterol, weight, height, waist, and hip measurements were obtained for 3121 randomly selected community participants (969 white men, 1409 white women, 205 African-American men, and 538 African-American women). Leisure-time physical activity was assessed from responses to a standard series of questions about participation in various leisure-time activities. We found an inverse relationship between leisure-time activities and high-density lipoprotein cholesterol levels in African Americans, in contrast to a positive association observed in whites; however, these associations failed to reach statistical significance after controlling for age and body composition. These results confirm a strong association of body composition with high-density lipoprotein cholesterol and support continued interventions designed to reduce overall body weight, particularly upper body weight. The results further suggest that the relationships between some life-style factors and HDL levels may be different among minorities.

Black or African American↗
PubMed1993

Tuberculosis and AIDS in South Carolina: a case-control study.

The epidemiologic features of tuberculosis patients with AIDS or HIV infection in this study do not appear to be different from those reported from previous studies. Tuberculosis patients with AIDS or HIV positive antibody in South Carolina are predominantly black males who live in the urban areas and are 25 to 44 years old. They have more extrapulmonary sites and more anergic reactions to tuberculin tests. Physicians and other public health workers should be aware of the abnormal clinical and laboratory manifestations of tuberculosis patients with AIDS and HIV infection. It is also imperative for tuberculosis control programs to offer counseling and HIV antibody testing to tuberculosis patients.

AIDS-Related Opportunistic Infections↗
PubMed1992

Sensitivity and specificity of death certificate diagnoses for dementing illnesses, 1988-1990.

OBJECTIVE: To evaluate the extent to which mortality data, which is often used to track secular trends for specific diseases, underestimates the prevalence of dementia. DESIGN: Retrospective analysis of existing data. SETTING: Department of Mental Health inpatient facilities in South Carolina. SUBJECTS: Inpatients at Department of Mental Health facilities who were listed in the South Carolina Statewide Alzheimer's Disease and Related Disorders Registry and who died between 1988 and 1990 (n = 450). MAIN OUTCOME MEASURES: Sensitivity and specificity of dementia diagnoses on death certificates compared to medical record diagnoses for inpatients with a pre-mortem dementia diagnosis. RESULTS: Twenty-three percent of death certificates contained any dementia diagnosis (104/450). The sensitivity of death certificates varied by type of dementia (28 percent for Alzheimer's disease; 8 percent for multi-infarct dementia) as well as by race, sex, and age. CONCLUSIONS: Mortality statistics substantially underestimate the prevalence of dementing illnesses and do not fully represent the public health burden of dementia.

Age Factors↗
PubMed1992

Craniofacial screening profile: quick screening for congenital malformations.

The correct identification of syndromes and other congenital malformations at an early age is critical for the child, family and care providers. Most specialists who conduct large screenings of young children are not adequately trained to recognize signs and symptoms that should lead to appropriate referral to the clinical geneticist and/or diagnostic team. A systematic approach for recognizing important signs is presented here; a Craniofacial Screening Profile. Following a brief training program, the Profile was validated by 39 speech-language pathologists in screening 3,539 kindergarten and first grade children. The results were excellent (specificity was 99.6%), demonstrating that with limited training, specialists can effectively screen for important signs and symptoms of a major group of syndromes and other congenital malformations.

Child↗
PubMed1992

Lower extremity injuries in runners. Advances in prediction.

Recreational and competitive running is practised by many individuals to improve cardiorespiratory function and general well-being. The major negative aspect of running is the high rate of injuries to the lower extremities. Several well-designed population-based studies have found no major differences in injury rates between men and women; no increasing effect of age on injuries; a declining injury rate with more years of running experience; no substantial effect of weight or height; an uncertain effect of psychological factors; and a strong effect of previous injury on future injuries. Among the modifiable risk factors studied, weekly distance is the strongest predictor of future injuries. Other training characteristics (speed, frequency, surface, timing) have little or no effect on future injuries after accounting for distance run. More studies are needed to address the effects of appropriate stretching practices and abrupt change in training patterns. For recreational runners who have sustained injuries, especially within the past year, a reduction in running to below 32 km per week is recommended. For those about to begin a running programme, moderation is the best advice. For competitive runners, great care should be taken to ensure that prior injuries are sufficiently healed before attempting any racing event, particularly a marathon.

Body Mass Index↗
PubMed1992

Physiological, anthropometric, and training correlates of running economy.

Potential physiological, anthropometric, and training determinants of running economy (RE) were studied in a heterogeneous group of habitual distance runners (N = 188, 119 males, 69 females). RE was measured as VO2 (ml.kg-1.min-1) during level treadmill running at 161 m.min-1 (6 mph) (VO2-6). Examined as potential determinants of RE were heart rate and ventilation while running at 6 mph (HR6, VE6), VO2max (ml.kg-1 x min-1), % fat, age, gender, height, weight, estimated leg mass, typical training pace, training volume, and sit-and-reach test performance. RE was entered as the dependent variable and the potential determinants as independent variables in zero-order correlation and multiple regression analyses. Zero-order correlation analysis found VO2max, HR6, and VE6 to be significantly, positively correlated with VO2-6 (P < 0.001). Multiple regression analysis, in which the independent effect of each predictor variable was examined, revealed VO2-6 to be positively correlated with VO2max (P < 0.001), HR6 (P < 0.001), VE6 (P < 0.001), and age (P < 0.05) and negatively correlated with weight (P < 0.01). These findings indicate that, in a diverse group of runners, better RE (VO2-6) is associated with lower VO2max, lower submaximal exercise VE and HR, lower age, and greater weight.

Adult↗
PubMed1991

A report on dementia in South Carolina, 1988-1990.

With the over age 65 population growing at a faster rate than the under 65 population, and with the strong effect of age on the incidence and prevalence of dementia, South Carolina faces a major health problem among its elderly residents by the year 2010. This report summarizes data on the 4,283 persons identified by the Statewide Alzheimer's Disease and Related Disorders Registry during the period 1988 to 1990. Sixty-one percent of these cases had a diagnosis of Alzheimer's disease or senile dementia and 62 percent of these were currently institutionalized. The demographic distribution of the AD cases did not change over the three-year period. Compared to community cases, those in institutions were generally older, and more likely to be women, unmarried, and white. The average time from onset of symptoms to diagnosis of AD was about five years.

Aged↗
PubMed1991

Exercise and the incidence of upper respiratory tract infections.

We examined illness patterns in a cohort of 530 male and female runners who completed a monthly log for 12 months. The average number of upper respiratory tract infections (URTIs) per person per year for the cohort was 1.2. An upper respiratory tract infection was indicated by the report of any of the following symptoms; runny nose, sore throat, or cough. Using a multiple logistic regression model, the following factors were found to be associated with having one or more URTIs in the follow-up period: living alone (odds ratio = 2.27, 95% CI = 1.01, 5.09), running mileage (486-865 miles, odds ratio = 2.00, 95% CI = 1.01, 2.78; 866-1388 miles, odds ratio = 3.50, 95% CI = 1.52, 4.44; greater than 1388 miles, odds ratio = 2.96, 95% CI = 1.30, 3.68), body mass index greater than the 75th percentile (odds ratio = 0.58, 95% CI = 0.35, 0.94), and male gender (odds ratio = 0.14, 95% CI = 0.03, 0.68). A significant interaction was found to exist between gender and alcohol use, with the association between alcohol use and upper respiratory tract infections being positive in males and negative in females. These results suggest that running dosage (mileage) is a significant risk factor for upper respiratory tract infections in this group of exercisers.

Adolescent↗
PubMed1990

Patterns of non-response to a mail survey.

This paper describes a basic investigation of possible non-response bias in a mail survey. We compare characteristics of responders and non-responders to a mail survey of health outcomes among participants of a longitudinal study of physical activity, physical fitness, and health. Results indicate that, at the first clinic visit, the responders were essentially the same as the non-responders on personal health history and laboratory measurements, while reporting significantly more family history of specific chronic diseases (cardiovascular disease, hypertension, stroke). The male responders were younger and reported more positive health behaviors as well as better weight and treadmill times at the first clinic visit. These results suggest that both response groups were equally healthy at entry, and that individuals who had family members with certain chronic conditions and who had positive health behaviors were more likely to respond (participate) in this health-related survey. Differences of this type could affect interpretation of future analyses. This work illustrates the importance of incorporating methods to examine non-response into any epidemiologic study.

Bias↗
PubMed1990

Menstrual dysfunction among habitual runners.

The association of menstrual dysfunction and weekly running mileage was investigated in a group of habitual women runners, categorized into high mileage runners (30 or more miles/week) and low mileage runners. Both mileage groups reported menstrual changes and weight loss since starting to run. Menstrual irregularities (35 or more days between cycles) were reported more often among the high mileage women than among the low mileage women (p = 0.001). However, after controlling for cycle irregularity before starting a running program, the effect of mileage was no longer statistically significant. While these results suggest that pre-running menstrual irregularity is more important than higher doses of weekly mileage, further investigations are needed to assess the role of potentially confounding factors such as stress, diet, and other lifestyle changes that may occur with increased exercise.

Adult↗
PubMed1990

Distribution of major dementias by race and sex in South Carolina.

Preliminary data from the newly implemented Registry for dementing illnesses was used to examine the distribution of four types of dementia in black and white residents of South Carolina. The data for 1464 subjects were abstracted by field research nurses in state mental health facilities. Overall, 649 patients (44.3%) were black and 765 (52.3%) were white. Women comprised 53.8% of all cases of dementia in this study. The overall distribution included 66% Alzheimer's disease (AD), 12% multi-infarct dementia (MID), 10% alcoholic dementia (ALC), nine percent other-medical and three percent other-unspecified. Though the proportion of blacks does not exceed one-third of the total population of S.C., blacks comprised 44.3% of all cases of dementia. AD accounted for 79% of all cases of dementia in women, but only 51% of such cases in demented men, who showed an apparent preoponderance of MID and alcoholic dementia. The frequency distribution of MID was equal in blacks and whites. Educational level had no discernible effects. Though not directly comparable, these preliminary findings are similar to those of the Copiah County Study, including a higher frequency of AD with advancing age.

Aged↗
PubMed1990

The need for an Alzheimer's disease patient registry in South Carolina.

There has been considerable interest in establishing a statewide registry of Alzheimer's disease patients. The need for such a registry, how it could be effectively organized, and the potential benefits from such a registry are discussed. The current status of the South Carolina Registry for Dementing Illnesses is reported.

Aged↗
PubMed1989

Age, physical activity, physical fitness, body composition, and incidence of orthopedic problems.

The incidence of orthopedic problems was examined in 5,582 men and women who attended the Cooper Clinic in Dallas, Texas between 1974 and 1982. The effects of age, physical activity, physical fitness, and body mass index (BMI) on the occurrence of these problems were examined using a proportional hazards approach. The expected risk of orthopedic problems per person-year was 0.045 for men and 0.046 for women. For men, physical fitness, BMI, and physical activity were associated with orthopedic problems, while for women, physical activity was the main predictor. Age was not a factor for either gender. The effect of change in physical fitness, physical activity, and BMI was examined in a subset of 2,325 persons with more than one visit to the clinic. For women, physical activity and a decrease in BMI were associated with orthopedic problems, while for men none of those factors were significant. Again, age was not a factor in either group. The absence of any age effect on the occurrence of problems suggests that with regard to orthopedic problems, moderate amounts of physical activity in generally healthy persons may be recommended without special consideration as to age.

Adolescent↗