Showing papers by "Frank E. Speizer published in 1984"
764 citations
TL;DR: This cross-sectional study demonstrates the feasibility of measurement of nonspecific bronchial responsiveness in epidemiologic studies, and its relationship to age and wheeze symptoms in children.
Abstract: Nonspecific bronchial responsiveness was assessed with eucapneic hyperpnea to subfreezing air in a population-based sample of 134 adults and 213 children in East Boston, Massachusetts. Increased responsiveness was considered to be present if the decrease in forced expiratory volume in one second with cold air divided by the initial vital capacity was greater than 9%. Men and women had similar bronchial responsiveness, but children and young adults (24 yr of age and younger) were significantly more likely to be responders than were older subjects (p < 0.001). Children with a doctor’s diagnosis of asthma at any time in the past were twice as likely (42.9%) to be responders as were nonasthmatic children (19%) (p = 0.004). Ninety-two percent (11/12) of currently active asthmatics were responders. However, a large percentage of asymptomatic children had increased levels of bronchial responsiveness (18.9%). This cross-sectional study demonstrates the feasibility of measurement of nonspecific bronchial responsiv...
101 citations
TL;DR: In this paper, four thousand elementary-school-age children from a rural area of western Pennsylvania participated in a cross-sectional survey that consisted of a standardized respiratory questionnaire completed by their parents and spirometric testing at school.
Abstract: Four thousand elementary-school-age children from a rural area of western Pennsylvania participated in a cross-sectional survey that consisted of a standardized respiratory questionnaire completed by their parents and spirometric testing at school. Spirographic tracings were digitized to obtain the FVC, FEV0.75, FEF25-75, max75, and max90, which were standardized for height, age, and sex for the subsequent analyses. Independent associations of potential risk factors with the standardized pulmonary function measures were evaluated with multiple regression techniques. Asthma, persistent wheeze, and parental smoking habits, especially those of the mothers, were associated with lower flow rates. The effect of parental smoking was primarily due to smoking by the mother and was stronger in girls. In female children of currently smoking mothers, FEF25-75 was 96% of predicted, max75 was 95% of predicted, and max90 was 92% of predicted; each flow measure was 98% of predicted in male children of smoking mothers. Pr...
93 citations
TL;DR: The findings of this cross-sectional analysis suggest that in adults, both airways responsiveness and cigarette smoking are important predictors of wheezing and asthma and the data suggest that airway hyperresponsiveness and atopy are independent traits.
Abstract: The response to eucapnic hyperventilation with subfreezing air was studied in a population based sample of 171 adults, all of whom also completed a respiratory questionnaire, spirometry, and skin testing. A positive response to the cold air challenge was defined as [initial FEV1-post-challenge FEV1)/initial FVC) X 100) greater than or equal to 9%. Cigarette smoking was with a positive cold air response: 12 of 128 current and ex-smokers (9.4%) versus 1 of 43 nonsmokers (2.3%) (p = 0.095). Among current and ex-smokers, a positive response to the cold air challenge was significantly associated with asthma (p = 0.046). Using a logistic regression model, both current smoking and response to cold air were significant predictors of the presence of "persistent wheeze" or asthma. A positive skin test to any of the 4 environmental antigens used (ragweed, housedust, trees, and grasses) was significantly associated with cigarette smoking (p = 0.018) and hay fever (p = 0.003 among current and ex-smokers) but not with wheezing or asthma. Though not statistically significant, cold air responders had a lower percentage of positive skin test reactivity than nonreactors. The findings of this cross-sectional analysis suggest that in adults, both airways responsiveness and cigarette smoking are important predictors of wheezing and asthma. Furthermore, the data suggest that airway hyperresponsiveness and atopy are independent traits. However, in adults, these traits are associated with cigarette smoking, a common environmental exposure.
91 citations
TL;DR: Prior epidemiologic analysis of these data have demonstrated an effect of maternal smoking on the level of pulmonary function in their children, and genetic heritability was found to be consistent through time and was the same for parents and their children.
Abstract: Measurements of level of pulmonary function (one second forced expiratory volume (FEV1) and forced expiratory flow between the 25% and 75% volume points (FEF 25-75)) were obtained on members of 404 nuclear families living in East Boston, Massachusetts in 1974. These families were ascertained through a random sample of children aged 5-9 years. Measurements were obtained on family members on three separate occasions during a 5-year period. These data were subjected to the techniques of path analysis to study the relative contributions of heredity and environment to individual levels of pulmonary function. Genetic heritability was found to be consistent through time (41-47%) and was the same for parents and their children. Common familial environmental effects on level of pulmonary function explained 1-4% of the variability in children and 11-28% in adults. Furthermore, we were able to confirm prior epidemiologic analysis of these data which have demonstrated an effect of maternal smoking on the level of pulmonary function in their children.
83 citations
TL;DR: The results suggest that passive exposure to maternal cigarette smoke may have important effects on the development of pulmonary function in children.
Abstract: We investigated the effects of maternal cigarette smoking on pulmonary function in a cohort of children and adolescents observed prospectively for seven years. A multivariate analysis revealed that after correction for previous forced expiratory volume in one second (FEV1), age, height, change in height, and cigarette smoking in the child, or adolescent, maternal cigarette smoking significantly lowered the expected average annual increase in FEV1 (P = 0.015). On the basis of this analysis, it is estimated that if two children have the same initial FEV1, age, height, increase in height, and personal cigarette-smoking history, but the mother of one has smoked throughout the child's life whereas the mother of the other has not, the difference in the change in FEV1 over time in the exposed child, as compared with that in the unexposed child, will be approximately 28, 51, and 101 ml after one, two, and five years, respectively, or a reduction of 10.7, 9.5, and 7.0 per cent, respectively, in the expected increase. These results suggest that passive exposure to maternal cigarette smoke may have important effects on the development of pulmonary function in children.
72 citations
TL;DR: There was no association between OC use and breast cancer among women with a positive history of breast cancer in the mother or sister or with OC use before their first pregnancy, and there was no consistent pattern of excess risk with increasing duration.
Abstract: Among 989 cases of breast cancer and 9,890 controls selected from a cohort of married, female registered nurses aged 30-55 years, the relative risk (RR) of breast cancer for women who had ever used oral contraceptives (OC) compared with those who had never used them was 1.0, with 95% confidence limits 0.9-1.2. Among OC users, there was no consistent pattern of excess risk with increasing duration; in fact, the few women who had used OC longest (greater than 10 yr) had a slightly lower risk than never-users. Moreover, there was no association between OC use and breast cancer among women with a positive history of breast cancer in the mother or sister or with OC use before their first pregnancy. The only subgroup of women among whom any adverse effect was apparent was current OC users aged 50-55 years (two onsets expected vs. seven observed). This finding is consistent with earlier reports of an increased risk of breast cancer among older OC users; however, it is also likely to reflect, at least to some extent, the play of chance, since at ages 45-49 and in each younger age group fewer cases than expected were observed among current OC users.
67 citations
TL;DR: Results indicate that passive smoking in the 6- to 11-year-old child does not continue to affect the growth rate of height and that the observed association between attained height and maternal smoking behaviour is due to exposures in utero and/or during infancy and the preschool years.
Abstract: The attained height and height growth rate of 9273 children participating in a longitudinal study of the health effects of air pollutants were analysed to assess the association between passive exposure to cigarette smoke and physical growth between 6 and 11 years of age. Children were measured annually for 2 to 6 years. Each height measurement was adjusted for sex and age by the NCHS anthropometric standards. Each child's adjusted heights were then re-expressed as level of attained height and growth rate. Attained height exhibited a dose-response relationship with amount of current maternal cigarette smoking (p less than 0.001). Children whose mothers smoked ten or more cigarettes daily were approximately 0.65 cm shorter than children of non-smokers, while children whose mothers smoked between 1 and 9 cigarettes per day were 0.45 cm shorter. However, passive smoking was not correlated with the child's growth rate. Exposure to paternal smoking was not significantly associated with height, either in terms of attained level or growth rate. These results indicate that passive smoking in the 6- to 11-year-old child does not continue to affect the growth rate of height and that the observed association between attained height and maternal smoking behaviour is due to exposures in utero and/or during infancy and the preschool years.
44 citations
TL;DR: A proportional hazards model was consistent with the findings of the standardised rate ratio, but in neither analysis was the increased risk of respiratory cancer in diesel exposed subjects statistically significant.
Abstract: A pilot study of the mortality of railway workers was undertaken to evaluate the feasibility of studying the association of exposure to diesel exhaust and cause specific mortality. The cohort consisted of 2519 white male subjects aged 45-64 with at least 10 years of railway service by 1967. Subjects were selected on the basis of job classification, and cause specific mortality was ascertained for subjects who died (n = 501) up to 1979. The total follow up period was 28.4 (X 1000) person-years. The standardised mortality ratio (SMR) for the cohort, based on United States national rates, was 87 (95% confidence limits 80, 95), and there were no significant differences from expected number of deaths for any specific neoplasm. The directly standardised rate ratio for respiratory cancer among diesel exposed subjects relative to unexposed subjects was 1.42 +/- 0.50 (means +/- SE). A proportional hazards model was consistent with the findings of the standardised rate ratio, but in neither analysis was the increased risk of respiratory cancer in diesel exposed subjects statistically significant.
41 citations
34 citations
TL;DR: Responses to vitamin A supplementation tend to be greater among women with lower previous total vitamin A intake, as assessed by questionnaire, and when the base-line retinol level and several other covariates were considered.
Abstract: Although dietary intake of vitamin A has little, if any, overall effect on blood retinol in generally well-nourished populations, subgroups may exist that would be responsive to supplementation. The hypothesis that vitamin A supplementation increases blood retinol in apparently well-fed individuals with lower than usual blood levels was tested in female health workers, with relatively low blood retinol values, who were randomly assigned to receive vitamin A (10,000 IU daily) or placebo. After 4 weeks the mean change in plasma retinol was -0.4 micrograms/dl for the group receiving placebo and +4.1 micrograms/dl (an increase of 9% over base-line values) for the group receiving vitamin A (P = .02). The results were similar when the base-line retinol level and several other covariates were considered. Thirteen women who had initially received placebo were then switched to vitamin A for 4 weeks. These women experienced a mean increase of 5.3 micrograms/dl in plasma retinol (P = .04). Responses to vitamin A supplementation tend to be greater among women with lower previous total vitamin A intake, as assessed by questionnaire [Spearman rank correlation coefficient (r) = 0.50; P = .01].
TL;DR: Among 714 premenopausal and 130 postmenopausal breast cancer cases matched with 8440 controls for age in years and menopausal status, risk indicators for breast cancer were similar, although most associations were stronger in the pre menopausal women.
Abstract: Among 714 premenopausal and 130 postmenopausal breast cancer cases matched with 8440 controls for age in years and menopausal status, risk indicators for breast cancer were similar, although most associations were stronger in the premenopausal women. Compared with nulliparous women, the relative risk (RR) for those with first birth before age 25 years was 0.7 (95% confidence limits [CL] from 0.5 to 0.9) among premenopausal women, and 0.7 (0.4–1.4) for postmenopausal women. In the premenopausal cases, a history of breast cancer in a sister gave a RR of 3.0 (2.1–4.1) and in a mother 1.9 (1.4–2.5), whereas for the postmenopausal women the RRs were 1.4 (0.6–3.1) and 13 (0.6–2.6), respectively. Fibrocystic breast disease was also a significant predictor of subsequent breast cancer in the premenopausal and postmenopausal women. In relation to women having a single birth, premenopausal women with six or more births had a risk of breast cancer of 0.6 (0.4–1.0), which was present even after adjustment for age at first birth.
TL;DR: The contamination of the Michigan food supply by polybrominated biphenyls (PBBs) in the mid-1970s appears to have had little or no impact on fetal mortality.
Abstract: The contamination of the Michigan food supply by polybrominated biphenyls (PBBs) in the mid-1970s appears to have had little or no impact on fetal mortality. Comparison of fetal death rates among residents of Lower Peninsula counties with a high percentage of quarantined farms and among residents of Upper Peninsula counties with no quarantined farms reveals no important differences in rates or trends after the contamination. Since counts of early spontaneous abortions are lacking, a complete assessment of the possible impact on reproductive outcome cannot be made.