Search PubMed⌕ Search

Biomedical subjects

S T Weiss

Publications and source records attributed to S T Weiss.

At least 163 records · Page 9Linked to original sources
PubMed1994

Relationship between dietary vitamin C intake and pulmonary function in the First National Health and Nutrition Examination Survey (NHANES I).

We assessed the relationship between dietary vitamin C intake and the level of pulmonary function (forced expiratory volume in 1 s, FEV1) in 2526 adults seen as part of the first National Health and Nutrition Examination Survey (NHANES I) between 1971 and 1974. Multiple-linear-regression analysis was performed with in FEV1 as the dependent variable. After age, height, body mass index, race, sex, cigarette smoking, and employment status were controlled for, dietary vitamin C intake was positively and significantly associated with the level of FEV1 (beta = 0.00132, P = 0.01). Interaction terms for vitamin C intake and smoking and vitamin C intake and respiratory disease were not significant. These data are consistent with the hypothesis that vitamin C intake has a protective effect on pulmonary function.

Adult↗
PubMed1994

Symptoms of anxiety and risk of coronary heart disease. The Normative Aging Study.

BACKGROUND: Several studies have suggested an increased risk of fatal coronary heart disease (CHD) among patients with panic disorder, phobic anxiety, and other anxiety disorders. We prospectively examined this association in the Normative Aging Study. METHODS AND RESULTS: An anxiety symptoms scale was constructed out of five items from the Cornell Medical Index, which was administered to the cohort at baseline. During 32 years of follow-up, we observed 402 cases of incident coronary heart disease (137 cases of nonfatal myocardial infarction, 134 cases of angina pectoris, and 131 cases of fatal CHD: made up of 26 cases of sudden cardiac death and 105 cases of nonsudden death). A nested case-control design (involving 1869 control subjects who remained free of diagnosed CHD) was used to assess the association between anxiety and risk of CHD. Compared with men reporting no symptoms of anxiety, men reporting two or more anxiety symptoms had elevated risks of fatal CHD (age-adjusted odds ratio [OR] = 3.20, 95% confidence interval [CI]: 1.27 to 8.09), and sudden death (age-adjusted OR = 5.73, 95% CI: 1.26 to 26.1). The multivariate OR after adjusting for a range of potential confounding variables was 1.94 (95% CI: 0.70-5.41) for fatal CHD and 4.46 (95% CI: 0.92-21.6) for sudden death. No excess risks were found for nonfatal myocardial infarction or angina. CONCLUSIONS: These data suggest an association between anxiety and fatal coronary heart disease, in particular, sudden cardiac death.

Adult↗
PubMed1994

Predictors of longitudinal change in methacholine airway responsiveness among middle-aged and older men: the Normative Aging Study.

Increasing nonspecific airway responsiveness during aging may precede and predispose to the development of asthma in later life. Characteristics potentially related to longitudinal change in methacholine airway responsiveness were examined over a 3-yr follow-up interval among 435 middle-aged and older men. Initial and follow-up evaluation included spirometry, allergy skin testing with common aeroallergens, measurement of the serum concentration of total IgE, and blood cell counts (total leukocytes and eosinophils, basophils, and neutrophils as a percentage of total leukocytes). The initial values and annual rates of change of these characteristics were examined by multiple linear regression as potential predictors of annual change in methacholine dose-response slope. Annual change in basophil count was directly related to change in dose-response slope (p = 0.02). Initial values and annual rates of change of other cell counts, pulmonary function, allergy skin test reactivity, and serum total IgE concentration were not significantly related to change in dose-response slope. Cigarette smoking history was also not significantly related to longitudinal change in dose-response slope. These data suggest that inflammatory mechanisms involving the basophil may be important in the development of increasing nonspecific airway responsiveness during aging.

Aged↗
PubMed1994

The influence of age, diagnosis, and gender on proper use of metered-dose inhalers.

Metered dose inhalers (MDIs) are widely used in clinical practice for administering pharmaceuticals targeted to the lung. It is well known that the inhalation technique used with MDIs can substantially influence the clinical response to inhaled medications. To determine the acceptability of MDI maneuvers, we studied 59 subjects (26 females and 33 males; age, 20 to 81 yr; mean age, 38 yr) to determine whether the MDI technique used by these individuals complied with published recommendations for acceptable inhalation technique. Measurements were made with an MDI adapter that contained an unobtrusive, lightweight, miniature sensing system. Inspiratory flow at the moment of MDI actuation (Va), the volume (integrated from airflow) at actuation as a fraction of total inspiratory volume (Va/VI), breath-holding time (tBH), and inspiratory volume as a fraction of FVC (VI/FVC) were determined from 59 uncoached inhalations. We defined an acceptable maneuver, based on published data, by four components: (1) inspiratory flow at actuation (Va) between 25 and 90 L/min; (2) actuation during early inspiration (0 < Va/VI < or = 0.20); (3) adequate breath-holding time (tBH > 4 s), and (4) a deep inhalation (VI/FVC > 0.50). For all subjects, only 25% of inhalation maneuvers met all four criteria for acceptability. We found that a significantly higher proportion of male than female subjects performed an acceptable MDI maneuver (43% versus 4%, p < 0.001). There were no significant differences in technique between younger and older subjects or between patients with a diagnosis of asthma or chronic obstructive pulmonary disease (COPD). We conclude that most patients use their MDIs incorrectly; females of all ages are much more likely to have improper MDI technique than are males.

Adult↗
PubMed1994

Clinical and symptom measures.

We present a review of specific health status measures, including symptoms, physical examination, and laboratory tests (exclusive of lung function tests), in terms of their suitability for assessing the presence and severity of asthma in epidemiologic and clinical research. We focus on the validity, reliability, and responsiveness to clinical intervention of these measures. Several adult questionnaires designed for epidemiologic research include questions on asthma and wheezing that have demonstrated repeatability and validity against concurrent measurements of nonspecific airway responsiveness. The International Union Against Tuberculosis Bronchial Symptoms Questionnaire was designed specifically to detect asthma and airway hyperresponsiveness in adult populations, and its reliability and validity have been well documented. A childhood questionnaire developed by Australian investigators has been demonstrated to provide information on asthma and wheezing that is reliable and valid against the criterion of concurrently measured nonspecific airway responsiveness. Although suitable for epidemiologic research, these questionnaires do not provide sufficient data on the severity of current asthma symptoms (aspects of which include intensity, duration, and frequency of symptoms) to be useful for clinical research involving subjects with established asthma. Many different methods of obtaining and analyzing symptom data have been used in clinical trials, but these have not received the methodologic scrutiny that allow the recommendation of a "best" approach for evaluating symptoms in clinical trials of interventions for asthma. The use of daily symptom diaries in short-term drug trials is common, but the optimal symptom-reporting interval for such studies has not been established. Similarly, a particular approach to integrating different symptoms (wheeze, dyspnea, cough, sputum) and the different aspects of these symptoms (intensity, duration, frequency) cannot be recommended on the basis of available data. Physical examination findings have little utility as asthma outcome measures because they may be normal between symptom episodes, they have relatively poor interobserver reliability, and they are relatively poor predictors of the outcome of emergency room visits for asthma. The finding of an elevated arterial PCO2 has utility as an indicator of a severe asthma attack, but arterial blood gas measurements have little other utility as asthma outcome measures. The chest radiograph is generally normal in patients with asthma and therefore not useful as an asthma outcome measure.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1994

The relationship of dietary fish intake to level of pulmonary function in the first National Health and Nutrition Survey (NHANES I)

Eicosapentaenoic acid (EPA), which predominates in marine fish, tends to counteract and inhibit the uptake and incorporation of arachidonic acid and membrane phospholipids and dilute arachidonic acid as a potential substrate for oxidation. Thus, fish intake may be protective for the occurrence of asthma and other pulmonary diseases. We wanted to examine the relationship between the effect of chronic dietary intake to fish and its relationship to level of pulmonary function. We performed this analysis using data from the First National Health and Nutritional Examination Survey (NHANES I). A detailed subsample of 2,526 adults had a medical history questionnaire, that included a 24-hour dietary recall, and performed spirometric examination. Log of forced expiratory volume in one second (FEV1) served as a dependent variable in regression analysis which included an adjustment for height, age, cigarette smoking and gender. When added to the regression model including the above variables dietary fish intake showed a protective association with FEV1 (beta = 0.008 +/- 0.004, p = 0.028). When smokers were excluded from the analysis, the effect of fish intake on pulmonary function appeared to increase slightly (beta = 0.0108 +/- 0.006, p = 0.61). These data suggest that chronic dietary intake of fish is associated with higher levels of pulmonary function and is consistent with the hypothesis of an effect of fish oil on arachidonic acid metabolism.

Adult↗
PubMed1994

Normal range of methacholine responsiveness in relation to prechallenge pulmonary function. The Normative Aging Study.

Methacholine airway responsiveness has been observed to be related to prechallenge level of pulmonary function; however, normal ranges of responsiveness for specific levels of lung function have not been reported. We examined methacholine airway responsiveness in relation to level of prechallenge pulmonary function in a sample of 547 middle-aged and elderly men who denied any history of respiratory illness or symptoms and who had normal levels of prechallenge FEV1 and FEV1/FVC ratio. The cumulative dose of methacholine provoking a 20 percent decline in FEV1 (PD20FEV1) was positively correlated with prechallenge FEV1 percent predicted (Spearman correlation r = 0.35, p < 0.0001). The fifth percentile of PD20FEV1, chosen as an estimate of the lower limit of the normal range, varied with the level of prechallenge FEV1. When applied to a larger sample of 838 men with normal pulmonary function, the use of FEV1-specific cut-off values to separate "normal" from "abnormal" PD20FEV1 did not improve the sensitivity or specificity of methacholine challenge as a test for questionnaire-reported asthma or wheezing. These data provide lower limits of normal PD20FEV1 which are specific for a subject's prechallenge FEV1; however, these FEV1-specific lower limits of normal PD20FEV1 provided no greater sensitivity and specificity for detecting asthma and wheezing than did a single lower limit of normal PD20FEV1 for all subjects.

Adult↗
PubMed1994

Smoking, changes in smoking habits, and rate of decline in FEV1: new insight into gender differences.

We wanted to test the hypothesis that gender differences in effects of smoking on the rate of decline in pulmonary function may be related to gender differences in the frequency of smoking. Data from the Vlagtwedde-Vlaardingen study in The Netherlands were analysed, to investigate the rate of decline in forced expiratory volume in one second (delta FEV1) in relation to smoking status and gender. 4,554 participants, initially aged 15-54 yrs, provided 16,900 pairs of observations at 3 yr intervals over 24 yrs of follow-up. Lifetime nonsmokers accounted for 11% of male participants and 45% of female participants. Compared with lifetime nonsmokers, estimated excess delta FEV1 for light, moderate, and heavy continued smokers was 4.4, 9.5 and 13.5 ml.yr-1 for men and 6.1, 10.8 and 18.8 ml.yr-1 for women, respectively. Female former smokers had a significantly more rapid delta FEV1 (beta = 4.4, SE = 1.6 ml.yr-1) than lifetime nonsmokers; but male former smokers had a slower rate of decline (beta = 4.1, SE = 2.3 ml.yr-1) than lifetime nonsmokers. Overall gender difference in smoking effects on delta FEV1 was statistically significant. Among subjects who smoked an identical amount at the beginning of the study period those who quit smoking during the period had a significantly slower delta FEV1 than those who continued smoking, for both men (beta = 20.6, SE = 3.9 ml.yr-1) and women (beta = 15.7, SE = 3.4 ml.yr-1). Younger quitters (< 45 yrs) benefited significantly more from smoking cessation than older quitters (> or = 45 yrs).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

The origins of childhood asthma.

Asthma is a clinical syndrome characterised by airways hyperresponsiveness and airway inflammation. There are three primary environmental exposures that lead to airway inflammation: allergen exposure, environmental tobacco smoke exposure, and viral respiratory infections. These exposures, separately or combined, result in clinical disease relatively early in childhood in genetically susceptible individuals. Treatment has evolved along two distinct lines: anti-inflammatory medications and exposure avoidance. Both approaches need further research and development.

Adolescent↗
PubMed1994

The relationships of abdominal obesity, hyperinsulinemia and saturated fat intake to serum lipid levels: the Normative Aging Study.

Abdominal obesity and hyperinsulinemia are associated with abnormalities in lipid metabolism and are important risk factors for coronary artery disease. Because hyperinsulinemia frequently accompanies abdominal obesity, it is unclear whether each is independently related to lipid abnormalities. Dietary saturated fat may influence these associations since it is associated with elevated lipid levels, obesity and hyperinsulinemia. Abdominal obesity (indexed as abdomen-to-hip circumference ratio), serum insulin level and dietary saturated fat intake were examined in relation to serum levels of lipids and lipoproteins in 878 male participants of the Normative Aging Study. Abdomen-to-hip ratio and insulin level were inversely related to high density lipoprotein cholesterol (HDL-C) (r = -0.17 and -0.21, respectively), and positively related to triglycerides (r = 0.25 and 0.36, respectively). Saturated fat intake was positively related to body mass index (r = 0.20), abdomen-to-hip ratio (r = 0.13), and insulin level (r = 0.10). In multiple linear regression models, abdomen-to-hip ratio was positively related to triglycerides and low density lipoprotein cholesterol (LDL-C) after adjusting for the effects of body mass index, alcohol intake, age, cigarette smoking and physical activity level, but was not significantly related to HDL-C. When serum insulin level was included as a covariate, abdomen-to-hip ratio remained significantly related to LDL-C and triglycerides, although its relationship with triglycerides was attenuated. Insulin level remained inversely related to HDL-C and triglycerides in multivariate models which adjusted for the effects of abdomen-to-hip ratio and BMI.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMed1993

Relation between blood lead and urinary biogenic amines in community-exposed men.

The cross-sectional relation between levels of urinary biogenic amines (dopamine, epinephrine, norepinephrine, and serotonin) and levels of blood lead was examined in a study of 645 male participants from a longitudinal study of aging. This stable population of men had initially been recruited from communities in and around Boston, Massachusetts, and had not been selected with regard to lead exposure. Blood lead samples and 24-hour and 2-hour urine specimens were collected during regularly scheduled clinic visits. In multivariate linear regression step-forward models, 24-hour epinephrine excretion was significantly and positively associated with blood lead (beta = 0.101 microgram(microgram/dl)-1 blood lead, SE (standard error) (beta) = 0.045, p = 0.026). Twenty-four-hour norepinephrine excretion was positively associated with blood lead (beta = 0.023 microgram(microgram/dl)-1 blood lead, SE(beta) = 0.029, p = 0.425), and both 24-hour dopamine (beta = -4.35 microgram(microgram/dl)-1 blood lead, SE(beta) = 6.90, p = 0.529) and 2-hour serotonin (beta = -0.348 microgram(microgram/dl)-1 blood lead, SE(beta) = 0.277, p = 0.210) excretion were negatively associated with blood lead; however, these relations did not achieve statistical significance. An increase of 10 micrograms/dl in blood lead was associated with an increase in epinephrine excretion of 11 micrograms/24 hours. These results support the hypothesis that epinephrine metabolism is influenced by low levels of lead exposure.

Adult↗
PubMed1993

Peripheral blood leukocyte count and respiratory symptoms.

The relationship of peripheral blood leukocyte count to respiratory symptoms was explored in data from the Second Annual National Health and Nutrition Survey (NHANES II). The study sample consisted of 9237 white and nonwhite US adults between the ages of 30 and 74 years. Three respiratory symptom outcomes were utilized: physician-diagnosed chronic cough and chronic bronchitis and self-reported frequent wheeze apart from colds or flu in the past 12 months. Peripheral blood leukocyte counts were performed using a Coulter counter, model FN. Logistic regression analysis was performed for each of the three respiratory symptom outcomes controlling for age, race, gender, and cigarette-years of smoke exposure. The peripheral blood leukocyte count was a significant predictor for each symptom. For a standard deviation increase in the log leukocyte count, the relative odds of wheezing was 1.93 (95% confidence level [CI], 1.47 to 2.52); for chronic cough, 2.29 (95% CI, 1.74 to 3.00); and for bronchitis, 2.44 (95% CI, 1.77 to 3.35). Analyses restricted to never smokers gave similar results. These data suggest that peripheral blood leukocyte count correlates with respiratory symptoms and are consistent with the hypothesis that the leukocyte count is a serum marker of inflammation.

Adult↗
PubMed1993

Relationship of dietary saturated fatty acids and body habitus to serum insulin concentrations: the Normative Aging Study.

The purpose of this study was to examine the relationship of body mass index, abdomen-hip ratio, and dietary intake to fasting and postprandial insulin concentrations among 652 men aged 43-85 y, followed in the Normative Aging Study. Log-transformed fasting insulin was significantly associated with body mass index, abdomen-hip ratio, total fat energy, and saturated fatty acid energy, with correlation coefficients ranging from 0.14 for total fat to 0.45 for body mass index. When multivariate models were used, body mass index, abdomen-hip ratio, and saturated fatty acid intake were statistically significant independent predictors of both fasting and postprandial insulin concentrations, after age, cigarette smoking, and physical activity were adjusted for. If saturated fatty acids as a percentage of total energy were to decrease from 14% to 8%, there would be an 18% decrease in fasting insulin and a 25% decrease in postprandial insulin. These data suggest that overall adiposity, abdominal obesity, and a diet high in saturated fatty acids are independent predictors for both fasting and postprandial insulin concentrations.

Adipose Tissue↗
PubMed1993

Predictors of the new onset of wheezing among middle-aged and older men. The Normative Aging Study.

Characteristics potentially associated with the development of wheeze symptoms were examined in a prospective cohort study of 624 middle-aged and older men who initially denied any history of wheezing or asthma. Initial evaluation included spirometry, methacholine challenge testing, allergy skin testing with common aeroallergens, serum total IgE concentration, blood leukocyte count, blood eosinophil count, and postural heart rate change (standing minus supine). The presence or absence of wheezing symptoms at follow-up 3 yr later was assessed by questionnaire. Multiple logistic regression was used to examine initial characteristics as predictors of subsequent wheezing. Current smoking was the strongest independent predictor of the new onset of wheezing (adjusted OR, 14.3; 95% confidence interval (CI), 3.9 to 52.3). The risk of developing new wheezing also increased with age (adjusted OR, 1.6; 95% CI, 0.9 to 2.9 comparing individual subjects 10 yr apart) and postural heart rate change at the initial examination (adjusted OR, 1.8; 95% CI, 1.1 to 3.0 comparing individual subjects differing by 10 beats/min). A significant association between greater methacholine airway responsiveness (PD20FEV1 < or = 16.8 mumol versus PD20FEV1 > 16.8 mumol) and the subsequent development of wheezing was observed among nonsmokers (adjusted OR, 5.2; 95% CI, 2.0 to 13.6) but not among current smokers. Other baseline variables were not independently related to the risk of developing wheezing symptoms. These data suggest that current smoking, age, nonspecific airway responsiveness, and altered autonomic function are independently related to the risk of developing wheezing symptoms in middle-aged and older men.

Adult↗
PubMed1993

Lung function, pre- and post-natal smoke exposure, and wheezing in the first year of life.

The relationship between initial level of lung function and subsequent wheezing, lower respiratory illness (LRI) was studied in 97 infants in whom the first measurement of pulmonary function (PFT) was made before 6 months of age. Occurrence of LRI was evaluated by standardized questionnaires at each well-baby visit, biweekly telephone calls to mothers, and review of all visits to physicians. Infant PFT was assessed by partial expiratory flow-volume curves and helium-dilution measurement of functional residual capacity (FRC). Maternal, prenatal smoking was assessed by urine cotinine and standard questionnaires. Infants who developed an LRI during the first year of life had lower preillness length-corrected forced expiratory flow at FRC (VFRC) than those who did not experience an LRI (males, 2.06 +/- 0.20 versus 2.32 +/- 0.29 ml/s/cm; females, 2.38 +/- 0.20 versus 2.91 +/- 0.26 ml/s/cm). Similar results were observed with FRC-corrected VFRC. No differences were observed for FRC. Differences in lung function were greatest in female infants whose mothers did not smoke during pregnancy (VFRC 2.67 +/- 0.25 versus 3.49 +/- 0.26 ml/s/cm for those with and without LRI, respectively; p = 0.03). History of maternal wheezing was more common in infants who experience an LRI, independent of maternal smoking. The results were not influenced by exposure to nonmaternal sources of environmental tobacco smoke in the postnatal period. Regression analyses that included data for multiple measurements of VFRC over the first year and took account of duration of follow-up demonstrated that lower levels of VFRC were associated with an increased frequency of LRI, especially in female infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1993

A longitudinal study of plasma cortisol concentration and pulmonary function decline in men. The Normative Aging Study.

Because of the important role of peripheral airways inflammation in the pathogenesis of asthma and COPD and because of the known anti-inflammatory actions of corticosteroids, we hypothesized that endogenous cortisol may influence the rate of decline of pulmonary function with aging. We examined the basal plasma cortisol concentration and serial spirometric measurements of 86 healthy men participating in the Normative Aging Study. Subjects selected for this study were free of any chronic illnesses and denied chronic use of any medications. Blood for cortisol determination was obtained with the subject in the supine position at 8:00 A.M. Two consecutive spirometric examinations that took place an average of 4.7 yr apart were employed in the analysis. Cross-sectional analysis revealed a weak (p = 0.08) direct relationship between the basal plasma cortisol concentration and FEV1. The cortisol concentration and FVC appeared unrelated. Longitudinal analysis revealed a significant (p = 0.008) relationship between the plasma cortisol concentration and the rate of decline of FEV1 over the follow-up interval after adjustment for age, height, smoking status, and initial FEV1 in a multivariate regression model. This multivariate model predicts that subjects with cortisol concentration 1 standard deviation (23.3 ng/ml) below the mean would experience FEV1 decline 71.6 ml/yr greater than subjects with cortisol concentration 1 standard deviation above the mean. This difference was comparable to the estimated 69.5 ml/yr difference between current and never smokers. Cortisol concentration was unrelated to the rate of decline of FVC. The data suggest that physiologic concentrations of cortisol may modulate the process responsible for the deterioration of ventilatory function with aging.

Aging↗
PubMed1993

Factors associated with bronchial responsiveness to histamine in a population sample of adults.

The association of age, gender, number of eosinophils, area of residence, cigarette smoking, respiratory symptom prevalence, and FEV1 with the level of bronchial responsiveness was studied in a random sample of 2,216 subjects aged 15 to 72 yr. Subjects participated in the Dutch longitudinal study on chronic obstructive pulmonary disease. In 18 yr of follow-up, 5,012 observations were collected. Interviewers used a standardized questionnaire to assess the presence of respiratory symptoms. Bronchial responsiveness was measured by a histamine challenge test. Because multiple measurements within a subject are correlated, multivariate regression methods for correlated outcome were used. A greater number of eosinophils, skin test positivity, and living in a rural area (Vlagtwedde) were associated with increased responsiveness, independently of the level of FEV1 and the presence of respiratory symptoms. Older age was associated with increased responsiveness, and this was even more so in subjects with symptoms. Cigarette smokers were more responsive than nonsmokers, but this association was not significant if the level of FEV1 was taken into account. Hyperresponsiveness was more likely to be present if the amount of cigarettes smoked per day was greater. The level of responsiveness did not differ significantly between males and females. For the same degree of obstruction, however, expressed as the FEV1/VC ratio, males tended to be less responsive than females. The analyses were repeated using the dose-response slope as a continuous measure of responsiveness and by applying a method to adjust for censoring the responsiveness data. These analyses yielded identical results.

Adult↗