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Biomedical subjects

R Andres

Publications and source records attributed to R Andres.

At least 55 records · Page 3Linked to original sources
PubMed1994

The sagittal waist diameter and mortality in men: the Baltimore Longitudinal Study on Aging.

The study objective was to determine the relationship between the abdominal sagittal diameter (waist depth) and subsequent mortality. This was a prospective study carried out in 981 male participants of the Baltimore Longitudinal Study on Aging which is a prospective study at the National Institute on Aging in Baltimore. The main outcome measures of the study were total and cause-specific mortality occurring during 17,529 person-years. The men were divided by age (cut-off point 55 years) at the start of follow-up. All-cause and coronary heart disease mortality rates (adjusted for age, height and body mass index) increased with increasing sagittal diameter in the younger group but not in the older group. No significant relationship was observed between the sagittal diameter and cancer mortality. Body mass index, skinfolds and waist/hip ratio were not significantly related to any of the endpoints studied. The increased risk of mortality with increasing sagittal diameter was somewhat stronger when the first ten years of follow-up were excluded and was more pronounced at lower levels of risk factors such as serum cholesterol, serum triglycerides, plasma glucose and diastolic blood pressure and in never plus ex-smokers compared to smokers. The study indicates that the abdominal sagittal diameter is a strong predictor of mortality in younger adult men independently of age, height, body mass index and conventional risk factors for mortality such as smoking, serum lipids and blood pressure. Regional adiposity may be a less strong risk factor for mortality in older men.

Adult↗
PubMed1993

Long-term effects of change in body weight on all-cause mortality. A review.

OBJECTIVE: To summarize published studies analyzing the effects of long-term change in body weight on all-cause mortality and have not been reported elsewhere in these proceedings. DATA SOURCES: Thirteen reports from 11 diverse population studies, 7 from the United States and 4 from Europe. STUDY SELECTION: All studies included a weight change period of 4 or more years, followed by a mortality assessment period of 8 or more years. All weight changes occurred in persons 17 years or older. DATA EXTRACTION: Data from individual studies are presented as number of participants, number of deaths, ages at initial and final weight measurements, duration of the mortality follow-up period, consideration of cigarette smoking and other potential confounders, exclusion criteria, temporal separation between the weight change and mortality follow-up periods, and the association between weight change and all-cause mortality. DATA SYNTHESIS: Results are summarized by weight change associated with the lowest mortality rate and by the effects of long-term weight loss on mortality rate. CONCLUSIONS: Despite the diversity of the populations studied, the degree of "clinical clean-up" at entry, the techniques used to assess weight change, and the differences in analytic techniques (including consideration of potentially confounding variables), certain conclusions may be drawn. Evidence suggests that the highest mortality rates occur in adults who either have lost weight or have gained excessive weight. The lowest mortality rates are generally associated with modest weight gains.

Body Weight↗
PubMed1993

An epidemiological test of the hyperinsulinemia-hypertension hypothesis.

The association between hyperinsulinemia and hypertension was tested in a population of 421 men and 228 women from the Baltimore Longitudinal Study of Aging. Subjects are white, middle-class, generally healthy, community-dwelling volunteers who ranged in age from 17-95 yr. Those with disease or medications known to influence any of the studied variables were excluded from the analysis. Twenty-five percent of the subjects were borderline or hypertensive [systolic blood pressure (BP) > or = 140 or diastolic BP > or = 90 mm Hg]. Standard oral glucose tolerance tests were performed; the logarithms of the fasting insulin level and insulin area were used in the analyses. In addition, body mass index and percent body fat (from age and skinfold thickness equations) and waist hip ratio were computed. In simple correlations, systolic BP and diastolic BP were statistically significantly related to insulin levels (only 1-4% of the variance was explained). Since age, body fat, fat distribution, insulin levels, and BP were highly intercorrelated, insulin and blood pressure correlations were examined after controlling for the confounding variables. Correlations of BP and insulin levels adjusted for age, body fat, and fat distribution were entirely nonsignificant. In this large noninterventive population study, the hyperinsulinemia-hypertension hypothesis is not confirmed.

Adolescent↗
PubMed1992

Salivary gland function and glucose metabolic status.

To study the relationship between glucose metabolic status and salivary gland function in different-aged persons, subjects with diabetes mellitus (DM = 11), impaired glucose tolerance (IGT = 26), and controls (n = 26), aged 24 to 93, were examined in the oral physiology component of the Baltimore Longitudinal Study of Aging. All were generally healthy (except DM) and nonmedicated. The controls and subjects with IGT were classified using World Health Organization criteria, and diabetic status was assessed using Hb1Ac levels. Unstimulated and 2% citrate-stimulated parotid and submandibular salivary flow rates were collected, and subjective responses to questions about salivary hypofunction were evaluated. No statistically significant differences were observed between the three groups, nor between young and old subjects with altered glucose metabolism. These findings suggest that among well-controlled individuals with altered glucose metabolism, salivary gland function is not significantly impaired.

Adult↗
PubMed1992

Glucose tolerance in women: the effects of age, body composition, and sex hormones.

OBJECTIVE: To determine the separate and interactive effects of age, phase of the menstrual cycle, menopausal hormone status, body fat mass, and regional fat distribution on glucose tolerance in healthy women. DESIGN: Retrospective study. SETTING: The Baltimore Longitudinal Study of Aging. PATIENTS: Two hundred sixty healthy women aged 22-89 years. MEASUREMENTS: Plasma levels of estradiol and progesterone, body mass index (BMI), waist-to-hip ratio (WHR), and plasma glucose values in the fasting state (FPG) as well as 120 minutes after 40 gm/m2 of oral glucose (G120) were measured for each participant. RESULTS: We found a progressive decline in oral glucose tolerance of 0.4 mM (6.7 mg/dL)/decade at G120) in women from early to late adult years, with no relationship to phase of the menstrual cycle and no abrupt change associated with the menopause. Multiple regression analysis revealed significant, independent effects of BMI and WHR on FPG and G120. The influence of age (P less than 0.01) on G120 was stronger than that of the BMI or WHR (P less than 0.05). There was no significant relationship between the levels of endogenous sex hormones and glucose tolerance after adjustments for age, BMI, and WHR. However, women taking oral contraceptives, but not those receiving postmenopausal replacement therapy, did exhibit mildly elevated G120 values. CONCLUSIONS: Age per se, and to a lesser extent BMI and WHR, but not levels of endogenous sex steroids, contribute to the physiological decline in glucose tolerance in older women.

Activities of Daily Living↗
PubMed1992

Long-term longitudinal measurements of plasma dehydroepiandrosterone sulfate in normal men.

Dehydroepiandrosterone sulfate (DS) was measured by direct tritium RIA in longitudinal plasma specimens from 97 normal healthy male participants in the Baltimore Longitudinal Study of Aging. Fasting blood was collected at regular visits (approximately 1.5 yr apart) over an average 13 yr of adulthood (cumulative age range: 32-83 yr). DS was measured in 3-4 widely spaced specimens from each subject. A decline in DS was found in 65 (67%) subjects, 13 subjects (13%) showed no change, and increases were found in the 19 remaining subjects during the study period. A plot of individual data points revealed the same pattern we had obtained previously from a cross-sectional study of a different normal male population. A plot of DS values vs. age among subjects whose DS increased during the study also revealed an age-related decline. Thus, the longitudinal decrease in circulating DS, long inferred from cross-sectional data, is confirmed for normal men in the present study. A more detailed study of every specimen collected during the study period from 12 of the Baltimore Longitudinal Study of Aging subjects (4 whose values tended to be low, 4 whose values tended to be high, and 4 whose values were near the mean) failed to reveal any patterns of variation that could be correlated with changes in life circumstances, health status, or any other discernible factors. Hence, the wide variability seen in DS among individuals within normal populations remains unexplained.

Adult↗
PubMed1992

Fasting respiratory exchange ratio and resting metabolic rate as predictors of weight gain: the Baltimore Longitudinal Study on Aging.

The authors followed 775 men (aged 18-98 years) participating in the Baltimore Longitudinal Study in Aging for an average of ten years. Resting metabolic rate and fasting respiratory exchange ratio (RER) were measured by indirect calorimetry on their first visit and related to subsequent weight change. Deviations from the predicted value of resting metabolic rates (predicted from their estimated fat-free mass) were calculated. Average weight change was 0.07 kg (s.d. 6.4 kg); 122 men (15.3%) gained more than 5 kg and 40 (5.2%) more than 10 kg during the follow-up. After adjustment for initial age, body mass index, fat-free mass, and duration of follow-up, RER, but not RMR or deviations from predicted RMR, was positively related to weight change (P less than 0.001). Major weight gain (from at least 5 kg to at least 15 kg) was related to initial RER in non-obese men only (initial body mass index less than 25 kg/m2). From Cox proportional hazard regression analyses the adjusted relative risk of gaining 5 kg or more in initially non-obese men with a fasting RER of 0.85 or more was calculated to be 2.42 (95% confidence interval: 1.10-5.32) compared to men with a fasting RER less than 0.76. It was concluded that a relatively high fasting RER is a weak but significant predictor of substantial weight gain in non-obese white men.

Adolescent↗
PubMed1991

Age as independent determinant of glucose tolerance.

It has been proposed that the decline in glucose tolerance with age is not a primary aging effect but is secondary to a combination of other age-associated characteristics, i.e., disease, medication, obesity, central and upper-body fat deposition, and inactivity. To test this hypothesis, we first eliminated from analysis the Baltimore Longitudinal Study of Aging participants with identifiable diseases or medications known to influence glucose tolerance. Seven hundred forty-three men and women, aged 17-92 yr, remained for analysis. As indices of fatness, body mass index and percent body fat were determined. As indices of body fat distribution, waist-hip ratio and subscapular triceps skin-fold ratio were calculated. As indices of fitness, physical activity level, determined by detailed questionnaire, and maximum 02 consumption were calculated. We tested whether the effect of age on glucose tolerance remains when data were adjusted for fatness, fitness, and fat distribution; 2-h glucose values were 6.61, 6.78, and 7.83 mM for young (17-39 yr), middle-aged (40-59 yr), and old (60-92 yr) men and 6.22, 6.22, and 7.28 mM for the three groups of women, respectively. The differences between the young and middle-aged groups were not significant, but the old groups had significantly higher values than young or middle-aged groups. Fatness, fitness, and fat distribution can account for the decline in glucose tolerance from the young adult to the middle-aged years. However, age remains a significant determinant of the further decline in glucose tolerance of healthy old subjects.

Adipose Tissue↗
PubMed1990

Continuing diet trends in men: the Baltimore Longitudinal Study of Aging (1961-1987).

Due to increasing evidence for the role of nutrition as a cause of illness and of the efforts of health agencies to induce Americans to change their diets, it is important to monitor populations for changes in their nutrient intakes. Seven-day diet records were collected from 105 free-living men in the 1960s, 1970s, and 1980s. Age range was initially 27 to 65 and finally 50 to 88 years. The men were divided into age groups so that longitudinal, time series, and cross-sectional analyses could distinguish among differences due to aging, cohort, and secular change. Longitudinal decreases over three decades of time include height, intakes of kcal/day, kcal/kg, kcal from fat, and cholesterol (all p less than .0001). Longitudinal increases over time include body weight, intakes of kcal from alcohol (p = .002), kcal from carbohydrate, and polyunsaturated to saturated fatty acid ratio (P/S) (all p less than .0001). Values that correlated cross-sectionally with age in the 1960s were height, kcal/day, kcal/kg, kcal from protein, and P/S ratio; height, intakes of kcal from protein, and fiber in the 1970s; and body weight, height, intakes of kcal from carbohydrate and fiber in the 1980s (all p less than .05). Protein consumption remained constant while carbohydrate increased as time passed. The more striking secular changes were in type and amount of fat consumed (42% to 34% of kcal, a 37% decline in cholesterol and a 72% increase in P/S ratio). Voluntary changes in the diets of these community-dwelling men indicate that, at any age, men can make beneficial changes in intake of nutrients that affect health.

Adult↗
PubMed1990

Body weight variability in men: metabolic rate, health and longevity.

The health implications of body weight fluctuation were examined using data from 846 men with a mean age of 56.4 years, enrolled in the Baltimore Longitudinal Study of Aging. Body weight fluctuation was studied in relation to three general categories of health-related outcome: (i) basal metabolic rate, (ii) risk factors for coronary heart disease (CHD), and (iii) rates of CHD, cancer mortality, and all-cause mortality. Weight fluctuation was defined as intraindividual variability in body weight about a time-dependent regression slope. Outcomes (i) and (ii) were described in terms of a subject's rate of change during the same time period. All analyses were adjusted for three covariates: age, level of obesity and linear trend in body weight over time. (i) Body weight variability is positively associated with changes in metabolic rate expressed either per surface area or per lean body mass (i.e. less decrease over time among the most weight-variable men). (ii) Body weight variability is associated with greater decreases in glucose tolerance and with greater increases in the ratio of subscapular to triceps skinfolds, but not with changes in systolic blood pressure, waist-hip ratio, serum cholesterol or triglyceride levels. (iii) Body weight variability is not predictive of subsequent CHD, cancer, or all-cause mortality. These results do not confirm previous findings regarding weight fluctuation and 'hard' endpoints but do raise the possibility that weight cycling might modify eventual cardiovascular risk via adipose redistribution or glucose tolerance impairment.

Adipose Tissue↗
PubMed1989

Studies in the distribution of body fat. III. Effects of cigarette smoking.

Cross-sectional associations between smoking habits, body mass index, and waist-hip ratio (WHR) were examined in 1122 men aged 19 to 102 years. Weight and body mass index were significantly lower in cigarette smokers than in nonsmokers when age was taken into account. The WHR in smokers was significantly higher than in nonsmokers. A graded dose-response relationship was found between the number of cigarettes smoked and the WHR. Longitudinal associations between changes in smoking habits and changes in the WHR were examined during follow-up visits. In the period between these pairs of visits, weight increased when subjects quit smoking and decreased when they started smoking, as expected. The increase in WHR among those who quit smoking was, however, significantly less than the expected increase if smoking had continued. The WHR in those who started smoking actually increased despite their loss of weight. These paradoxical changes in WHR indicate that there are harmful effects of cigarette smoking on the pattern of distribution of body fat. These facts introduce still another reason to suggest that the decision to initiate or to continue smoking to control body weight is unwise.

Adult↗
PubMed1989

Studies in the distribution of body fat: I. Effects of age, sex, and obesity.

The pattern of body fat distribution has been shown to be related to a large number of variables of clinical importance. A variety of indices have been devised, many of them simple enough to be useful in large-scale clinical studies. Relationships among these several indices and systematic information on the effects of age, sex, and obesity have, however, not been systematically studied. Five anthropometric ratios that classify individuals into different body types have been computed for 1179 men and women aged 17-96 years. These are: waist hip ratio, arm thigh ratio, waist thigh ratio, waist arm ratio, and subscapular triceps skinfold ratio. In general, the age patterns show progressive trends toward increasing upper and central body fat deposition with age. In women there tends to be a postmenopausal acceleration of this trend. The ratios are distinctly higher in men than in women and are also independently influenced by the body mass index. Predictive equations that take age and BMI into account for each of the indices for men and women have been provided.

Adipose Tissue↗
PubMed1989

Validation of a retrospective questionnaire assessing diet 10-15 years ago.

In 1985, 216 men, participants in the Baltimore Longitudinal Study of Aging, were asked to report on their usual diet during the period 1971-1975. The reference data for past diet consisted of multiple seven-day records collected between 1971 and 1975. The group was randomly assigned to complete the diet history either by personal interview or by mailed self-administered questionnaire. The items and response categories were identical in both cases. For both groups, the mean nutrient intake estimated by questionnaire was within +/- 10 per cent of the past diet record values for most nutrients. When the questionnaire was administered by an interviewer, correlations with past diet were approximately as good as those obtainable with present diet in other studies and indicate that useful studies of past diet can be performed with this questionnaire. Correlations for the mail group were considerably lower and suggest that assessment of past diet using this questionnaire format without personal instruction or callbacks may yield poor results. The effect of age was negligible, but response errors and change in diet since the target period had important effects on correlations with past diet in both interview and mail groups.

Aged↗
PubMed1989

The association of antiphospholipid antibodies with severe preeclampsia.

Over a 3-year period, we studied 43 women who presented with severe preeclampsia prior to 34 weeks' gestation. Seven (16%) had significant levels of antiphospholipid antibodies, whereas none of the normotensive controls of similar gestational age had antiphospholipid antibodies (P less than .001). Three of the seven women with antiphospholipid antibodies suffered the following complications during the peripartum period: 1) cerebral infarction and episodes of transient monocular blindness; 2) pulmonary embolism, deep venous thrombosis, and an autoimmune flare in the postpartum period; and 3) transient monocular blindness and amnesia after delivery. Our experience suggests that antiphospholipid antibodies are found in a substantial proportion of cases of early-onset severe preeclampsia and have important clinical implications. We suggest that patients with early-onset severe preeclampsia be screened for antiphospholipid antibodies; if antibodies are detected, these women should be considered for prophylactic anticoagulation therapy.

Autoantibodies↗
PubMed1989

Studies in the distribution of body fat. II. Longitudinal effects of change in weight.

Information on the effects of age, sex, obesity and weight change on the fat distribution pattern has not been systematically reported. As an index of body fat distribution, the waist hip circumference ratio (WHR) was computed in 370 men and 177 women aged 22-86 years, participants of the Baltimore Longitudinal Study of Aging. For cross-sectional analysis, initial data on the participants were analyzed; for longitudinal study, the changes in the measurements related to weight change during a 5-year follow-up were analyzed. From cross-sectional analysis: (1) waist circumference is larger in men than in women and increases progressively with age; (2) hip circumference shows no consistent age or sex differences; (3) thus, the well known sex differences in WHR are totally attributable to differences in waist circumference; (4) increases in WHR with age occur in both men and women. From longitudinal analysis of weight change: (1) changes in waist and hip circumferences are correlated directly with changes in weight in both sexes, but there are large differential sex effects; (2) in men, waist changes dominate; (3) in women, waist and hip changes are nearly the same; (4) thus, weight changes in men have large effects on the WHR, while in women changes in WHR are very small. Men, as a group, have a more dangerous fat distribution pattern than women, but men as a group will show a more beneficial pattern of change in WHR with weight control than women.

Adipose Tissue↗
PubMed1988

Fiber intake, age, and other coronary risk factors in men of the Baltimore Longitudinal Study (1959-1975).

Fiber intake was estimated by 7-day diet record in community-dwelling men of the Baltimore Longitudinal Study of Aging. The mean intake of 845 men (age 20-103) was 3.82 +/- 0.03 g crude fiber/day which corresponds to approximately 15 g/day of dietary fiber. Fiber intake increased across the age span (slope = +0.022 +/- 0.003 g/yr, p less than .01). Longitudinal analysis of 380 men, each of whom provided 3-8 diet records over an average period of 8 yr, indicated that the increase in fiber intake occurred in each age group and was not the result of differential survival. Fiber intake was negatively correlated with body mass index. After clinical screening to eliminate variables which could independently influence coronary risk factors, multiple regression analyses including age and body mass index were conducted to examine the effect of fiber (adjusted for total calorie intake) on blood pressure, blood lipids, and glucose tolerance. For systolic and diastolic blood pressure, triglyceride, and fasting plasma glucose, higher fiber intake was associated with lower levels of the risk factors (p less than .05).

Adult↗