Biomedical subjects

S T Weiss

Publications and source records attributed to S T Weiss.

280 records · Page 16Linked to original sources

PubMedDate not supplied

Relations of bone and blood lead to cognitive function: the VA Normative Aging Study.

The relationship between performance on cognitive tasks and circulating levels of lead in blood and accumulated levels of lead in bone was examined in 141 middle-aged and elderly men from a longitudinal study of aging. The mean (SD) blood lead level was low [5.5 (3.5) micrograms/dl], and mean patella and tibia lead levels were 31.7 (19.2) and 22.5 (12.2) micrograms/g bone mineral, respectively. Cognitive tests measured attention, perceptual speed, memory, language, and spatial copying. Regression models, adjusted for age and education, demonstrated that men with higher levels of blood lead recalled and defined fewer words, identified fewer line-drawn objects, and required more time to attain the same level of accuracy on a perceptual comparison test as men with the lowest level of blood lead. Men with higher levels of blood and bone (tibia) lead copied spatial figures less accurately; men with higher levels of bone (tibia) lead had slower responses for pattern memory. These findings suggest that low levels of lead contribute to impairments in cognitive function among elderly men.

Aged↗

PubMedDate not supplied

Cigarette smoking, aging, and decline in pulmonary function: A longitudinal study.

Three serial spirometric determinations of forced vital capacity (FVC) and forced expiratory volume in 1 sec (FEV1.0) were performed during a 10-yr period for 268 adult male cigarette smokers, 181 quitters, and 254 who had never smoked. Smokers were further divided into high- and low-tar consumption groups. Spirometric data were analyzed by repeated measures analyses of variance using time (aging) and smoking status as independent variables and age as a covariate. Results indicated that FVC and FEV1.0 were relatd to smoking status. For all age groups, nonsmokers performed best on spirometry, while current smokers performed worst. The decline in FEV1.0 over time was greatest in current smokers, especially the high-tar group. Loss of FVC over time was not influenced by smoking status.

Adult↗

PubMedDate not supplied

Smoking status and the electrocardiogram: a cross-sectional and longitudinal study.

Previous cross-sectional studies have shown age trends in electrocardiographic wave patterns, including leftward shift in frontal plane axis and decreases in R, S, and T wave amplitudes with age. The effects of smoking on electrocardiographic measurements have also been examined. Findings of several studies vary and include possible smoking-induced changes in T wave amplitude and frontal plane axis measurements. To examine both cross-sectionally and longitudinally the effects of cigarette smoking on electrocardiographic measurements, serial recordings obtained 5 yr apart were taken from 702 healthy male participants of the Normative Aging Study, who were 23-74 yr of age at their first examination. These men were classified as current smokers (at both baseline and follow-up examinations, N = 291), former smokers (men who stopped smoking prior to the baseline examination, N = 203), or never smokers (at any time, N = 208). At baseline, P-R interval duration was shorter in current smokers than in former or never smokers. Longitudinal results indicated that R, S, and T wave amplitudes decreased at greater rates in smokers than in nonsmokers. These findings suggest that changes in the electrocardiogram attributed to aging may be modified by smoking.

Adult↗

PubMedDate not supplied

The health effects of automobile exhaust. VI. Relationship of respiratory symptoms and pulmonary function in tunnel and turnpike workers.

To examine the effect of automobile exhaust on respiratory symptoms and pulmonary function, the authors studied 175 tunnel and turnpike workers employed by the Massachusetts Turnpike Authority on two occasions 3 yr apart beginning in 1972. A standard respiratory symptom and illness questionnaire was administered, spirometry was performed, and proximal hair lead and blood lead content were measured as biologic indices of automobile exhaust exposure. One hundred nine (63%) workers were current cigarette smokers, 41 (23%) were exsmokers, and 24 (14%) had never smoked. Smoking was strongly related to respiratory symptoms of cough (P less than .001) and phlegm production (P less than .001), but not to wheezing (P = .41), breathlessness (P = .14), bronchial asthma (P = .13), or frequent chest colds (P = .14). When workers were stratified by smoking status, no effect could be seen between high automobile exhaust exposure as measured by a variety of parameters and all of the above respiratory symptoms and illnesses. The level of pulmonary function [forced expiratory volume in 1 sec (FEV1.0) and forced vital capacity (FVC)] was not related to past or current exhaust exposure in a cross-sectional analysis when we controlled for age, height, and cigarette consumption. In a prospective analysis of 84 of these workers, the observed changes in FEV1.0 and FVC over 3 yr were unrelated to exhaust exposure after controlling for age, height, cigarette consumption, and initial level of pulmonary function.

Adult↗

PubMedDate not supplied

Relationship between cigarette smoking, chest size and body size in health-screened adult males.

Previous investigations have shown that chest dimensions and pulmonary function are positively correlated in healthy individuals. It is not known, however, whether the pulmonary effects of cigarette smoking may modify chest size during adulthood. The present study used cross-sectional data from 1557 healthy male participants in the Normative Aging Study of the Veterans Administration Outpatient Clinic, Boston. Because elastic recoil of the lung is decreased in cigarette smokers, we hypothesized that chest circumference would increase while chest expandability would decrease in these individuals. Preliminary analyses showed that smokers differed from non-smokers and former smokers in age, weight and fatness. For this reason, associations of chest dimensions with smoking status were evaluated after statistical correction for age and body size. With men of all ages grouped, chest expansion of smokers was significantly lower than non-smokers, but their chest size and shape were similar. When covariance analyses were performed separately for men under 50 and over 50 years, older smokers were characterized by slightly larger chests than non-smokers or former smokers, though there was no difference among younger men. Results of this study indicate that external chest dimensions of cigarette smokers reflect the pulmonary changes they experience, and demonstrate that a portion of the increased variability in chest measurements seen in older individuals is attributable to cigarette smoking.

Adult↗

PubMedDate not supplied

Hostility and the metabolic syndrome in older males: the normative aging study.

OBJECTIVE: Several studies have shown that hostility, as measured by the Minnesota Multiphasic Personality Inventory-derived Cook-Medley Hostility Scale (Ho), is positively associated with several cardiovascular risk factors, possibly accounting for the relationship between Ho scores and cardiovascular mortality. This study was undertaken to examine associations between hostility and cardiovascular risk factors representing the metabolic syndrome in 1,081 older men who participated in the Normative Aging Study. METHODS: Subjects included men who completed the Minnesota Multiphasic Personality Inventory in 1986 and who participated in a subsequent laboratory examination within 1 to 4 years. Total and subscale Ho scores were computed, and associations with anthropometric data, cigarette smoking, dietary information, serum lipids, blood pressure, and fasting glucose and insulin levels were examined. RESULTS: The total Ho score was positively associated with waist/hip ratio, body mass index, total caloric intake, fasting insulin level, and serum triglycerides. The Ho score was inversely related to education and high-density lipoprotein cholesterol concentration. Path analysis also suggested that the effects of hostility on insulin, triglycerides, and high-density lipoprotein cholesterol were mediated by its effects on body mass index and waist/hip ratio, which, in turn, exerted their effects on lipids and blood pressure through insulin. CONCLUSIONS: The results are consistent with those of prior research and also suggest that, in older men, hostility may be associated with a pattern of obesity, central adiposity, and insulin resistance, which can exert effects on blood pressure and serum lipids. Furthermore, effects of hostility on the metabolic syndrome appear to be mediated by body mass index and waist/hip ratio.

Adult↗

PubMedDate not supplied

Effect of polymorphism of the beta(2)-adrenergic receptor on response to regular use of albuterol in asthma.

BACKGROUND: Regular use of inhaled beta-adrenergic agonists may have adverse effects in some asthma patients. Polymorphisms of the beta(2)-adrenergic receptor (beta(2)-AR) can affect its regulation; however, results of smaller studies of the effects of such polymorphisms on response to beta-agonist therapy have been inconsistent. METHODS: We examined the possible effects of polymorphisms at codons 16 (beta(2)-AR-16) and 27 (beta(2)-AR-27) on response to albuterol by genotyping 190 asthmatics who had participated in a trial of regular versus as-needed albuterol use. RESULTS: During the 16-week treatment period, patients homozygous for arginine (Arg/Arg) at beta(2)-AR-16 who used albuterol regularly had a small decline in morning peak expiratory flow (AM PEF). This effect was magnified during a 4-week run-out period, when all patients returned to as-needed albuterol only. By the end of the study, Arg/Arg subjects who had used albuterol regularly had an AM PEF 30.5 +/- 12.1 liters/min lower (p = 0.012) than Arg/Arg patients who had used albuterol as needed only. Subjects homozygous for glycine at beta(2)-AR-16 showed no such decline. Evening PEF also declined in the Arg/Arg regular but not in as-need albuterol users. No significant differences between regular and as-needed treatment were associated with polymorphisms at beta(2)-AR-27. CONCLUSIONS: Polymorphisms of the beta(2)-AR may influence airway responses to regular inhaled beta-agonist treatment.

Adolescent↗

PubMedDate not supplied

Bronchial responsiveness to methacholine: relation to respiratory symptoms and pulmonary function.

A methacholine bronchial provocation test was administered to 290 subjects obtained from the 1,900 male volunteers participating in the Normative Aging Study. A positive response (less than 20% decline in FEV1) was obtained in 83 subjects. A positive response was associated with current smoking, presence of wheeze and reduced FEV1. Bronchial responsiveness, cigarette smoking, normal subjects, FEV1.

Adult↗

PubMedDate not supplied

Statistical methods for the analysis of the association between bronchial responsiveness and pulmonary function changes.

An autoregressive model for the analysis of longitudinal data was applied in the context of investigating the effect of bronchial responsiveness on the growth of pulmonary function in children. In the model used, the correlation between pulmonary function values within an individual decreases exponentially as the time between visits increases. The model incorporates both fixed and time-dependent covariates in a unified fashion and does not require complete data in all visits for each individual. Furthermore, the change in pulmonary function is not assumed to be linear over time. Using response to cold air data as a measure of bronchial responsiveness, we found that children who responded to cold air have a slower rate of growth in pulmonary function. In addition, the data suggested that the effect of cigarette smoking may be greater as the response to cold air increases. Extensions of the autoregressive approach to other correlation structures and to the case of unequidistant observations are discussed.

Adolescent↗

PubMedDate not supplied

The association of airways responsiveness to respiratory symptom prevalence and to pulmonary function in a random population sample.

In a random population sample of 1905 subjects we studied the occurrence of respiratory symptoms in relation to airways responsiveness. Responders (PC10 FEV1 to histamine at 16 mg.ml-1 or less) had crude prevalence rates two to three times higher than nonresponders. In logistic regression analysis, odds ratios were estimated for each threshold value, compared to the reference value (greater than 32 mg.ml-1), controlling for age, sex, area of residence, and smoking habit. Odds ratios increased with decreasing threshold values in a dose-response relationship for all symptoms, except for bronchitis periods. We analysed the association of airways responsiveness to pulmonary function level by multiple linear regression, controlling for age, sex, height, area of residence, and smoking habit. There was an inverse relationship of FEV1 level to threshold value. Male subjects within a threshold value of 1 mg.ml-1 had a mean adjusted FEV1 of 1170 ml less than males with a threshold value of greater than 32 mg.ml-1. The relationship of responsiveness to decline of FEV1 with time was studied in 186 male subjects who took part in five consecutive surveys from 1967 to 1981. The greatest mean adjusted yearly decline was noted in responding smokers: 35.3 ml per yr, compared to nonreactive nonsmokers: 10.9 ml per yr. Regression analysis of the yearly decline in 169 subjects with at least two pairs of two consecutive threshold tests revealed that the more positive tests subjects had, the greater was their mean adjusted yearly decline. It is concluded that airways responsiveness may be an important factor in the development of chronic obstructive pulmonary disease.

Adult↗