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Showing papers by "Frank E. Speizer published in 1992"


Journal ArticleDOI
TL;DR: It is concluded that maternal smoking during pregnancy is associated with significant reductions in forced expiratory flow rates in young infants, both when unadjusted and after controlling for infant size, age, sex, and passive exposure to environmental tobacco smoke between birth and the time of PF testing.
Abstract: We studied the effect of prenatal maternal cigarette smoking on the pulmonary function (PF) of 80 healthy infants tested shortly after birth (mean, 4.2 ± 1.9 wk). Mothers' prenatal smoking was measured by: (1) questionnaire reports at each prenatal visit of the number of cigarettes smoked per day, and (2) urine cotinine concentrations (corrected for creatlnine) obtained at each visit. Infant PF was assessed by partial expiratory flow-volume curves and hellum-dilutlon measurement of FRC. Forced expiratory flow rates were significantly lower in infants born to smoking mothers, both when unadjusted and after controlling for infant size, age, sex, and passive exposure to environmental tobacco smoke (ETS) between birth and the time of PF testing. Flow at functional residual capacity (FRC) in infants born to smoking mothers was lower than that found in infants whose mothers did not smoke during pregnancy (74.3 ± 15.9 versus 150.4 ± 8.9 ml/s; p = 0.0007). Differences remained significant when flow was corrected ...

542 citations


Journal ArticleDOI
TL;DR: Application of circadian principles to the design of hospital work schedules may result in improved health and safety for nurses and patients.
Abstract: A hospital-based survey on shift work, sleep, and accidents was carried out among 635 Massachusetts nurses. In comparison to nurses who worked only day/evening shifts, rotators had more sleep/wake cycle disruption and nodded off more at work. Rotators had twice the odds of nodding off while driving to or from work and twice the odds of a reported accident or error related to sleepiness. Application of circadian principles to the design of hospital work schedules may result in improved health and safety for nurses and patients.

525 citations


Journal ArticleDOI
TL;DR: No associations were observed between intakes of energy, protein, sucrose, carbohydrate, or fiber and risk of diabetes among women with BMIs less than 29 kg/m2 and inverse associations were attenuated among obese women (BMIs greater than or equal to 29).

442 citations


Journal ArticleDOI
TL;DR: Current estrogen use is associated with a reduction in the incidence of coronary heart disease as well as in mortality from cardiovascular disease, but it is not associated with any change in the risk of stroke.
Abstract: BACKGROUND The effect of postmenopausal estrogen therapy on the risk of cardiovascular disease remains controversial. Our 1985 report in the Journal, based on four years of follow-up, suggested that estrogen therapy reduced the risk of coronary heart disease, but a report published simultaneously from the Framingham Study suggested that the risk was increased. In addition, studies of the effect of estrogens on stroke have yielded conflicting results. METHODS We followed 48,470 postmenopausal women, 30 to 63 years old, who were participants in the Nurses' Health Study, and who did not have a history of cancer or cardiovascular disease at base line. During up to 10 years of follow-up (337,854 person-years), we documented 224 strokes, 405 cases of major coronary disease (nonfatal myocardial infarctions or deaths from coronary causes), and 1263 deaths from all causes. RESULTS After adjustment for age and other risk factors, the overall relative risk of major coronary disease in women currently taking estrogen was 0.56 (95 percent confidence interval, 0.40 to 0.80); the risk was significantly reduced among women with either natural or surgical menopause. We observed no effect of the duration of estrogen use independent of age. The findings were similar in analyses limited to women who had recently visited their physicians (relative risk, 0.45; 95 percent confidence interval, 0.31 to 0.66) and in a low-risk group that excluded women reporting current cigarette smoking, diabetes, hypertension, hypercholesterolemia, or a Quetelet index above the 90th percentile (relative risk, 0.53; 95 percent confidence interval, 0.31 to 0.91). The relative risk for current and former users of estrogen as compared with those who had never used it was 0.89 (95 percent confidence interval, 0.78 to 1.00) for total mortality and 0.72 (95 percent confidence interval, 0.55 to 0.95) for mortality from cardiovascular disease. The relative risk of stroke when current users were compared with those who had never used estrogen was 0.97 (95 percent confidence interval, 0.65 to 1.45), with no marked differences according to type of stroke. CONCLUSIONS Current estrogen use is associated with a reduction in the incidence of coronary heart disease as well as in mortality from cardiovascular disease, but it is not associated with any change in the risk of stroke.

390 citations


Journal ArticleDOI
21 Oct 1992-JAMA
TL;DR: Evidence is provided against both an adverse influence of fat intake and a protective effect of fiber consumption by middle-aged women on breast cancer incidence over 8 years, and the positive association between intake of animal fat and risk of colon cancer observed in many studies provides ample reason to limit this source of energy.
Abstract: Objective. —To address the hypotheses that dietary fat increases and fiber decreases the risk of breast cancer. Design. —Prospective cohort study with dietary assessment at baseline, using a validated, self-administered food frequency questionnaire. Setting/Participants. —89 494 women in the Nurses' Health Study who were 34 through 59 years of age in 1980 and who were followed up for 8 years (>95% complete). Results. —1439 incident cases of breast cancer were diagnosed, including 774 among postmenopausal women. After adjustment for age, established risk factors, and total energy intake, we observed no evidence of any positive association between total fat intake and breast cancer incidence (relative risks [RRs] for increasing quintiles of fat intake were 1.0, 0.85, 0.96, 0.91, and 0.90; 95% confidence interval for highest vs lowest quintile, 0.77 to 1.07). Among postmenopausal women alone, corresponding RRs were 1.0, 0.89,1.00, 0.95, and 0.91. Comparing extreme deciles of total fat intake (≥49% vs Conclusions. —These data provide evidence against both an adverse influence of fat intake and a protective effect of fiber consumption by middle-aged women on breast cancer incidence over 8 years. Nevertheless, the positive association between intake of animal fat and risk of colon cancer observed in many studies provides ample reason to limit this source of energy. (JAMA. 1992;268:2037-2044)

374 citations


Journal ArticleDOI
08 Aug 1992-BMJ
TL;DR: Dietary carotenoids, although not necessarily beta carotene, and long term vitamin C supplementation may decrease the risk of cataracts severe enough to require extraction, according to a prospective cohort study of female registered nurses.
Abstract: OBJECTIVE--To examine prospectively the association between dietary intake of vitamins C and E, carotene, and riboflavin and cataract extraction in women. DESIGN--Prospective cohort study beginning in 1980 with eight years of follow up. SETTING--11 states of the United States. PARTICIPANTS--Female registered nurses who were 45 to 67 years of age. 50,828 women were included in 1980 and others were added as they became 45 years of age. MAIN OUTCOME MEASURE--Incidence of extraction of senile cataracts. RESULTS--493 cataracts were extracted during 470,302 person years of follow up. Intake of carotene and vitamin A was inversely associated with cataract: in multivariate analyses, women in the highest fifth of total vitamin A intake (excluding supplements) had a 39% lower risk of cataract relative to women in the lowest fifth (relative risk 0.61; 95% confidence interval 0.45 to 0.81). Neither riboflavin nor dietary vitamins E or C were associated with cataract in a multivariate analysis. Among specific food items spinach (rather than carrots, the greatest source of beta carotene) was most consistently associated with a lower relative risk. The risk of cataract was 45% lower among women who used vitamin C supplements for 10 or more years(relative risk 0.55 (0.32 to 0.96)), but no association was noted for multivitamin intake. CONCLUSION--Dietary carotenoids, although not necessarily beta carotene, and long term vitamin C supplementation may decrease the risk of cataracts severe enough to require extraction.

292 citations


Journal ArticleDOI
TL;DR: In this paper, the effects of smoking history and current smoking behavior on the rate of loss of pulmonary function during adult life were analyzed by longitudinal methods to describe the effects on lung function.
Abstract: Data from a random sample of 8,191 men and women selected in six U.S. cities and examined on three occasions over a 6-yr follow-up period were analyzed by longitudinal methods to describe the effects of smoking history and current smoking behavior on rate of loss of pulmonary function during adult life. Former smokers had age- and height-adjusted rates of decline (34.3 ml/yr for men and 29.6 ml/yr for women) comparable with those of never smokers (37.8 ml/yr for men and 29.0 ml/yr for women) but much smaller than those of continuing smokers (52.9 ml/yr for men and 38.0 ml/yr for women). The accelerated rate of loss of FEV1 among smokers depended linearly on the number of cigarettes smoked per day during the interval between examinations. The estimated increase in rate of loss associated with smoking was 12.6 ml/yr per pack/day for men and 7.2 ml/yr per pack/day for women. These longitudinal estimates of the effects of smoking were approximately 50% larger than estimates obtained from cross-sectional analysis of the initial pulmonary function examination. Men who started smoking had accelerated rates of loss (55.9 ml/yr) as did women (43.1 ml/yr). Smokers who stopped smoking between examinations had reduced declines (41.2 ml/yr for men and 28.7 ml/yr for women) compared with continuing smokers. The age-specific rates of loss suggest that the benefits of cessation may be greatest among the youngest smokers.(ABSTRACT TRUNCATED AT 250 WORDS)

238 citations


Journal ArticleDOI
TL;DR: In both men and women, reporting of any respiratory symptoms was associated with both a reduction in initial lung function and more rapid decline in height-adjusted FEV1, and men with cough or phlegm and women with cough alone showed accelerated loss inFEV1.
Abstract: The relation of respiratory symptoms and lung function has not been extensively investigated. To determine better the rate of FEV1 decline in subjects reporting persistent wheeze, chronic cough, chronic phlegm, and/or dyspnea, longitudinal data from an adult population sample of 3,948 subjects (1,757 men; 2,191 women) followed for 12 yr were analyzed. At the initial and subsequent follow-up visits, subjects completed a standardized respiratory questionnaire and performed spirometry using the same methods and spirometers. Subjects were categorized based on the presence or absence of self-reported respiratory symptoms (persistent wheeze, chronic cough, chronic phlegm, or shortness of breath) at the initial visit. Sex-specific linear regression models were fitted to determine the effect of these respiratory symptoms on lung function. In both men and women, reporting of any respiratory symptoms was associated with both a reduction in initial lung function and more rapid decline in height-adjusted FEV1. Furthe...

161 citations


Journal ArticleDOI
26 Aug 1992-JAMA
TL;DR: Smoking appears to increase the risk of cataract extraction in women according to a prospective cohort study beginning in 1980 and continuing with 8 years of follow-up.
Abstract: Objective. —To examine prospectively the association between cigarette smoking and the risk of cataract extraction in women. Design. —Prospective cohort study beginning in 1980 with 8 years of follow-up. Setting. —United States, multistate. Participants. —Registered nurses 45 to 67 years of age and free of diagnosed cancer. There were 50 828 women included in 1980 and others were added as they became 45 years of age. Main Outcome Measure. —Incidence of senile cataract extraction. Results. —We documented 493 incident senile cataracts diagnosed and extracted during 470302 person-years of follow-up. The age-adjusted relative risk (RR) among women who smoked at least 65 pack-years was 1.63(95% confidence interval [Cl], 1.18 to 2.26; Pfor trend,.02). A similar increase in RR was noted when smoking was assessed in terms of number of cigarettes currently smoked or number of cigarettes smoked by past smokers. Results were also similar after adjusting for other potential risk factors for cataract. Smoking was also strongly associated with posterior subcapsular cataract specifically (RR, 2.59; 95% Cl, 1.49 to 4.50 for ≥65-pack-year smokers relative to nonsmokers). Conclusion. —Smoking appears to increase the risk of cataract extraction. ( JAMA . 1992;268:994-998)

149 citations


Journal ArticleDOI
TL;DR: It is predicted that a female who develops asthma at age 7 would experience a 5% reduction in FEV1 by age 10 and a 7% deficit by age 15, and from this analysis, it would predict that a male who develops asthmatic disease at age 9 would experience an 8% deficit.
Abstract: Data from a longitudinal study of childhood factors influencing the development of chronic obstructive lung disease were used to assess the effects of asthma on lung function development in male and female children. A population-based cohort of 602 white children, initially aged 5 to 9 yr, was observed prospectively for 13 yr. Spirometry was performed and a standardized respiratory and illness questionnaire was administered by trained interviewers on a yearly basis. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and forced expiratory flow between 25 and 75% of vital capacity (FEF25-75) were used as measures of lung function. The total number of children reporting asthma over the course of the study was 67. Male asthmatic subjects (n = 42) had larger average percentage of predicted FVC than nonasthmatic males (n = 277). Female asthmatic subjects (n = 23) had a lower average percentage of predicted FEV1 than nonasthmatic females (n = 260). In a multivariate analysis of the individual lung function measures, adjusting for previous level of pulmonary function, age, height, change in height, and personal and maternal smoking, males reporting active asthma had a significantly larger FVC than males with no history of asthma. In contrast, females with active asthma had a significantly smaller FEV1 than females with no history of asthma. Both males and females with active asthma had decreased FEF25-75. From our analysis, we would predict that a female who develops asthma at age 7 would experience a 5% reduction in FEV1 by age 10 and a 7% deficit by age 15.(ABSTRACT TRUNCATED AT 250 WORDS)

141 citations


Journal ArticleDOI
TL;DR: Preliminary data indicate that postmenopausal hormone therapy is unlikely to be associated with a material increase in the incidence of non-insulin-dependent diabetes mellitus among women.

Journal ArticleDOI
TL;DR: No significant associations were observed between risk of basal cell carcinoma and energy-adjusted intake of dietary fat, carotenoids with vitamin A activity, and retinol, vitamin C, vitamin D, and vitamin E, either with or without supplements.

Journal ArticleDOI
TL;DR: The data suggest that long-term past use of estrogen replacement therapy is not related to risk, that current estrogen use increases risk of breast cancer to a modest degree, and that the addition of progesterone does not remove the increased risk observed with current use of unopposed estrogen.
Abstract: We prospectively examined the use of hormone replacement therapy in relation to breast cancer incidence in a cohort of women 30 to 55 years of age in 1976. During 12 years of follow-up (480,665 person-years) among postmenopausal women, 1,050 incident cases of breast cancer were documented. Overall, past users of replacement estrogen were not at increased risk. After adjustment for established risk factors, type of menopause, age at menopause, and current age, the rate ratio (RR) was 0.91, 95 percent confidence interval (CI) = 0.78–1.07. the risk of breast cancer was elevated significantly among current users (RR = 1.33, CI = 1.12–1.57); after adjusting for age, we observed no evidence of increasing risk with increasing duration of use among current users (P trend = 0.41), or among past users (P trend = 0.46). Women currently using unopposed estrogen (RR = 1.42, CI = 1.19–1.70), estrogen and progesterone (RR = 1.54, CI = 0.99–2.39), or progesterone alone (RR = 2.52, CI = 0.66–9.63), were all at increased risk of breast cancer compared with never users. These data suggest that long-term past use of estrogen replacement therapy is not related to risk, that current estrogen use increases risk of breast cancer to a modest degree, and that the addition of progesterone does not remove the increased risk observed with current use of unopposed estrogen.

Journal ArticleDOI
TL;DR: The effects of ambient ozone (O3) on respiratory function and acute respiratory symptoms were evaluated in 143 7- to 9-yr-old schoolchildren followed longitudinally at 1- to 2wk intervals at three schools in Pedregal, Mexico City.
Abstract: The effects of ambient ozone (O3) on respiratory function and acute respiratory symptoms were evaluated in 143 7- to 9-yr-old schoolchildren followed longitudinally at 1- to 2-wk intervals over a period of 6 months at three schools in Pedregal, Mexico City. The maximum O3 level exceeded the World Health Organization guideline of 80 ppb and the U.S. standard of 120 ppb in every week. For an increase from lowest to highest in the mean O3 level during the 48 hr before spirometry (53 ppb), logistic regression estimated relative odds of 1.7 for a child reporting cough/phlegm on the day of spirometry. For the full population, the mean O3 level during the hour before spirometry, not adjusted for temperature and humidity, predicted a significant decrement in FVC but not in FEV1 or FEF25-75. In contrast, the mean O3 level during the previous 24-, 48-, and 168-h periods predicted significant decrements in FEV1 and FEF25-75 but not in FVC. Ozone was consistently associated with a greater decrement in lung function for the 15 children with chronic phlegm as compared with the children without chronic cough, chronic phlegm, or wheeze. Ozone in the previous 24-, 48-, and 168-h periods predicted decrements in FEV1 for children of mothers who were current or former smokers, but not for children of mothers who were never smokers. Many of these effects were reduced in multiple regression analyses including temperature and humidity, as temperature and O3 were highly correlated.(ABSTRACT TRUNCATED AT 250 WORDS)

Journal ArticleDOI
TL;DR: The data suggest that past or current oral contraceptive use does not substantially influence subsequent risk of Type 2 diabetes, and there was no effect modification by obesity, family history of diabetes, or physical activity.
Abstract: We examined the association between oral contraceptive use and incidence of Type 2 (non-insulin-dependent) diabetes mellitus among 115117 female nurses free of diabetes, cardiovascular disease and cancer in 1976 and followed-up for 12 years. During 1237440 person years of follow-up, 2276 women who provided information on oral contraceptive use were clinically diagnosed with Type 2 diabetes. Women who used oral contraceptives in the past had only a slight and marginally increased relative risk of 1.10 (95% confidence interval 1.01, 1.21) compared to those women who had never used oral contraceptives after controlling for known risk factors of disease. We found no evidence of increased risk with longer duration of use or with shorter interval since last use. Current users did not have an increased risk of Type 2 diabetes (relative risk = 0.86, 95% confidence interval 0.46, 1.61) when compared to women who had never used the drug. There was no effect modification by obesity, family history of diabetes, or physical activity. These data suggest that past or current oral contraceptive use does not substantially influence subsequent risk of Type 2 diabetes.

Journal ArticleDOI
TL;DR: Despite a temporary diabetogenic effect of pregnancy, parity is not associated with an increased risk of subsequent clinical NIDDM, and the importance of control for confounding by age and obesity in evaluating these associations is underscored.

Journal ArticleDOI
TL;DR: A retrospective cohort of husbands of members of the Nurses' Health Study found that vasectomy is a reliable and widely accepted method of contraception, but there is some uncertainty and few data about a possible long-term adverse effect on health.
Abstract: Background Vasectomy is a reliable and widely accepted method of contraception, but there is some uncertainty and few data about a possible long-term adverse effect on health. Methods We examined the relation between vasectomy and mortality rates from cardiovascular disease, cancer, and all causes in a retrospective cohort of husbands of members of the Nurses' Health Study. In 1989 we obtained data by questionnaire on 14,607 men who had undergone vasectomy as of 1976 and 14,607 men who had not. Results Among the men who were free of cancer at the start of the study, 1052 died: 446 of cardiovascular disease, 341 of cancer, and 265 of other causes. Vasectomy was associated with reductions in mortality from all causes (age-adjusted relative risk, 0.85; 95 percent confidence interval, 0.76 to 0.96) and mortality from cardiovascular disease (relative risk, 0.76; 95 percent confidence interval, 0.63 to 0.92). Vasectomy was unrelated to mortality from all forms of cancer (relative risk, 1.01; 95 percent...

Journal ArticleDOI
01 Mar 1992-Thorax
TL;DR: To the authors' knowledge, this is the first report of an association between carboxyhaemoglobin concentrations and KCO in a population of never smoking men and women.
Abstract: BACKGROUND: Data on reference values of transfer factor variables in general populations of asymptomatic never smokers are limited. The aim of this study was to examine the relation between test variables and age, height, haemoglobin concentration and carboxyhaemoglobin concentration. METHODS: Measurements of single breath transfer factor for carbon monoxide (TLCO) were obtained for a randomly selected sample of never smokers in north western Europe who were 18-73 years old and had no respiratory symptoms or disorders. Two recordings of TLCO with a ratio of inspiratory vital capacity to forced vital capacity of greater than 0.09 were obtained by standardised techniques for 304 subjects. RESULTS: The measurement errors expressed as a percentage of the common mean value of TLCO, volume adjusted TLCO (KCO), and alveolar volume (VA) were 4.5%, 4.2%, and 2.4% respectively. Multiple linear regressions showed sex specific effects of height and age on TLCO, and, in addition, of haemoglobin and carboxyhaemoglobin concentrations on KCO. VA was associated with height but not with age. The 5th and 95th centiles for TLCO and KCO in men and women were between 78% and 82% and between 120% and 127%, respectively, of predicted values when age and height were taken into account. CONCLUSION: Reference equations and normal values for transfer test variables in a large healthy population of never smokers are described in relation to age, height, and haemoglobin concentrations. To our knowledge, this is the first report of an association between carboxyhaemoglobin concentrations and KCO in a population of never smoking men and women.


Journal ArticleDOI
TL;DR: It is concluded that nasal disorders are associated with lower respiratory tract symptoms in children in a random population of 718 children in East Boston, Massachusetts.
Abstract: We examined the relationship of nasal disorders, defined as frequent colds and sinus trouble, to lower respiratory tract symptoms in a random population of 718 children aged 4 to 11 years in East Boston, Massachusetts. Frequent colds were significantly associated with maternal smoking (odds ratio (OR) = 3.00; 95% confidence interval (Cl) = 1.97, 4.58), and so was sinus trouble (OR = 4.73; 95% Cl = 1.78, 12.51). After adjustment for maternal smoking, age and sex, frequent colds (OR = 2.88; 95% Cl = 1.87, 4.42) and sinus trouble (OR = 4.95, 95% CI = 1.83, 13.39) remained significant predictors of lower respiratory tract symptoms in separate logistic regressions. If one restricted the cohort to the 513 children who also had personal smoking information and adjusted for this variable as well, the results for colds were unchanged (OR = 2.94; 95% Cl = 1.78, 4.84) but the results for sinus trouble were now not statistically significant (OR = 2.30, 95% Cl = 0.67, 7.94). We conclude that nasal disorders are associated with lower respiratory tract symptoms in children. © 1992 Wiley-Liss, Inc.

Journal ArticleDOI
TL;DR: Vasectomy is not associated with an increase in overall mortality or mortality from cardiovascular disease, but there was an apparent increase in the risk of cancer 20 or more years after vasectomy that requires further study.
Abstract: Background Vasectomy is a reliable and widely accepted method of contraception, but there is some uncertainty and few data about a possible long-term adverse effect on health. Methods We examined the relation between vasectomy and mortality rates from cardiovascular disease, cancer, and all causes in a retrospective cohort of husbands of members of the Nurses' Health Study. In 1989 we obtained data by questionnaire on 14,607 men who had undergone vasectomy as of 1976 and 14,607 men who had not. Results Among the men who were free of cancer at the start of the study, 1052 died: 446 of cardiovascular disease, 341 of cancer, and 265 of other causes. Vasectomy was associated with reductions in mortality from all causes (age-adjusted relative risk, 0.85; 95 percent confidence interval, 0.76 to 0.96) and mortality from cardiovascular disease (relative risk, 0.76; 95 percent confidence interval, 0.63 to 0.92). Vasectomy was unrelated to mortality from all forms of cancer (relative risk, 1.01; 95 percent...


01 Jan 1992
TL;DR: Cigarette smoking causes an accelerated annual loss of pulmonary function that may be underestimated by cross-sectional studies, and the benefits of cessation may be greatest among the youn­ gest smokers.
Abstract: SUMMARY Data from a random sample of 8,191 men and women selected In six U.S.cities and examined on three occasions over a 6-yr follow-up period were analyzed by longitudinal methods to describe the effects of smoking history and current smoking behavior on rate of loss of pulmo­ nary function during adult life. Former smokers had age- and height-adjusted rates of decline (34.3 ml/yr for men and 29.6 ml/yr for women) comparable with those of never smokers (37.8mllyr for men and 29.0ml/yr for women) but much smaller than those of continuing smokers (52.9 ml/yr for men and 38.0 ml/yr for women). The accelerated rate of loss of FEV 1 among smokers depended linearly on the number of cigarettes smoked per day during the interval between examinations. The estimated Increase in rate of loss associated with smoking was 12.6ml/yr per pack/day for men and 7.2ml/yr per pack/day for women. These longitudinal estimates of the effects of smoking were approximately 50% larger than estimates obtained from cross-sectional analysis of the initial pul­ monary function examination. Men who started smoking had accelerated rates of loss (55.9 ml/yr) as did women (43.1 ml/yr). ,Smokers who stopped smoking between examinations had reduced declines (41.2 ml/yr for men and 28.7 ml/yr for women) compared with continuing smokers. The age-specific rates of loss suggest that the benefits of cessation may be greatest among the youn­ gest smokers. The changes associated with starting or cessation of smoking were much smaller than those found In cross-sectional analyses of these data. In summary, cigarette smoking causes an accelerated annual loss of pulmonary function that may be underestimated by cross-sectional studies. Those who stop smoking will experience only a small recovery in pulmonaryfunction level, but they will cease to lose pulmonary function at an accelerated rate. AM REV RESPIR DIS 1992; 146:1345-1348 As a part of the Six Cities Study of Air Pol­ lution and Health, we selected a random sam­ ple of adult residents of Six Cities in the east­ ern United States and examined them at 3-yr intervals over a 6-yr period (1). In a previous report, we described analyses of the baseline spirometric data showing that levels of FVC and FEV1 in both current and former smokers depended linearly on total pack-years of cig­ arette smoking. Current cigarette smokers had an additional deficit relative to former smokers with the same smoking history as measured in pack -years, This report uses data obtained during a 6-yr follow-up of this co­ hort to obtain longitudinal estimates of the effects of current smoking behavior on the rate of loss of pulmonary function between examinations.


Journal ArticleDOI
TL;DR: In this article, the authors examined the relation between vasectomy and mortality rates from cardiovascular disease, cancer, and all causes in a retrospective cohort of husbands of members of the Nurses' Health Study.
Abstract: Background Vasectomy is a reliable and widely accepted method of contraception, but there is some uncertainty and few data about a possible long-term adverse effect on health. Methods We examined the relation between vasectomy and mortality rates from cardiovascular disease, cancer, and all causes in a retrospective cohort of husbands of members of the Nurses' Health Study. In 1989 we obtained data by questionnaire on 14,607 men who had undergone vasectomy as of 1976 and 14,607 men who had not. Results Among the men who were free of cancer at the start of the study, 1052 died: 446 of cardiovascular disease, 341 of cancer, and 265 of other causes. Vasectomy was associated with reductions in mortality from all causes (age-adjusted relative risk, 0.85; 95 percent confidence interval, 0.76 to 0.96) and mortality from cardiovascular disease (relative risk, 0.76; 95 percent confidence interval, 0.63 to 0.92). Vasectomy was unrelated to mortality from all forms of cancer (relative risk, 1.01; 95 percent...