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Biomedical subjects

B Rosner

Publications and source records attributed to B Rosner.

At least 91 records · Page 5Linked to original sources
PubMed1995

Alcohol consumption and mortality among women.

BACKGROUND: Studies in men suggest that light-to-moderate alcohol intake is associated with a reduction in overall mortality, due primarily to a reduced risk of coronary heart disease. Among women with similar levels of alcohol consumption, an increased risk of breast cancer has been noted that complicates the balance of risks and benefits. METHODS: We conducted a prospective study among 85,709 women, 34 to 59 years of age and without a history of myocardial infarction, angina, stroke, or cancer, who completed a dietary questionnaire in 1980. During the 12-year follow-up period, 2658 deaths were documented. RESULTS: The relative risks of death in drinkers as compared with nondrinkers were 0.83 (95 percent confidence interval, 0.74 to 0.93) for women who consumed 1.5 to 4.9 g of alcohol per day (one to three drinks per week), 0.88 (95 percent confidence interval, 0.80 to 0.98) for those who consumed 5.0 to 29.9 g per day, and 1.19 (95 percent confidence interval, 1.02 to 1.38) for those who consumed 30 g or more per day, after adjustment for other predictors of mortality. Light-to-moderate drinking (1.5 to 29.9 g per day) was associated with a decreased risk of death from cardiovascular disease; heavier drinking was associated with an increased risk of death from other causes, particularly breast cancer and cirrhosis. The benefit associated with light-to-moderate drinking was most apparent among women with risk factors for coronary heart disease and those 50 years of age or older. CONCLUSIONS: Among women, light-to-moderate alcohol consumption is associated with a reduced mortality rate, but this apparent survival benefit appears largely confined to women at greater risk for coronary heart disease.

Adult↗
PubMed1995

Prospective study of toenail selenium levels and cancer among women.

BACKGROUND: Inverse associations between selenium status and cancer risk have been observed in animal studies, ecologic studies, and some case-control and prospective studies. Whereas results of some prospective studies have suggested an overall inverse relationship between selenium levels and cancer, other prospective studies have failed to confirm this finding. Prospective data on women are particularly limited because fewer women than men have been studied prospectively. PURPOSE: The aim of this study was to prospectively examine the relationship between selenium levels in toenails (previously shown to reflect selenium intake) and incidence of cancer among women. METHODS: The Nurses' Health Study cohort began in 1976 with 121,700 female nurses aged 30-55 years living in 11 U.S. states. In 1982, we requested toenail clippings from the members of the cohort, and 62,641 participants with no history of cancer returned these clippings. During 41 months of follow-up, 503 cases of cancer other than breast cancer (results previously reported) or nonmelanoma skin cancer were analyzed. For each case patient, a control subject was chosen from women who remained free of diagnosed cancer, matched by age and by date of nail return. RESULTS: No inverse association was observed between selenium levels in toenails and cancer risk. The age- and smoking-adjusted relative risk (RR), comparing the highest with the lowest quintile of toenail selenium level, was 1.44 (95% confidence interval [CI] = 0.97-2.13), and the trend across quintiles was marginally significant (two-sided P = .06). Comparing the highest with the lowest decile, the RR (age- and smoking-adjusted) was 1.77 (95% CI = 1.04-3.02). When these data were combined with the data from 434 breast cancer case patients and their matched control subjects identified in parallel from this same cohort, the RR comparing the highest with the lowest quintile was 1.24 (95% CI = 0.93-1.65). Toenail selenium level was not inversely associated with cancer at any major site, including uterine cancer, colorectal cancer, melanoma, ovarian cancer, or lung cancer (after adjusting for smoking); in fact, nonsignificant positive associations were observed at several sites. CONCLUSIONS: Toenail selenium levels were not inversely associated with cancer risk in this study. IMPLICATIONS: These data, in conjunction with previous findings of no association between toenail selenium status and breast cancer risk, strongly suggest that higher selenium intake within the range consumed by most U.S. women (as reflected by toenail selenium levels) is not protective against overall cancer incidence in women.

Adult↗
PubMed1995

Evidence for a positive linear relation between blood pressure and mortality in elderly people.

Many studies of blood pressure in the elderly have found higher death rates in groups with the lowest blood pressure than in those with intermediate values. In a large community study, we examined whether these findings are real or artifacts of short follow-up, co-morbidity, or low blood pressure in people near death. In 1982-83, we assessed drug use, medical history, disability, physical function, and blood pressure in 3657 residents of East Boston, Massachusetts, aged 65 and older. We identified all deaths (1709) up to 1992 and followed up survivors for an average of 10.5 (range 9.5-11.0) years. After adjustment for confounding variables (including frailty and disorders such as congestive heart failure and myocardial infarction) and exclusion of deaths within the first 3 years of follow-up, higher systolic pressure predicted linear increases in cardiovascular (p < 0.0001) and total (p < 0.0007) mortality. Higher diastolic pressure predicted increases in cardiovascular (p = 0.006) but not total (p = 0.48) mortality. These results differed from those for the first 3 years, during which groups with the lowest systolic and diastolic pressures had the highest death rates. In the long term, lower blood pressure in old age, as in middle age, is associated with better survival. Short-term findings may differ because of associations of co-morbidity and frailty with blood pressure near death. Overall, the findings support recommendations to treat high blood pressure in elderly people.

Aged↗
PubMed1995

Weight, weight change, and coronary heart disease in women. Risk within the 'normal' weight range.

OBJECTIVE--To assess the validity of the 1990 US weight guidelines for women that support a substantial gain in weight at approximately 35 years of age and recommend a range of body mass index (BMI) (defined as weight in kilograms divided by the square of height in meters) from 21 to 27 kg/m2, in terms of coronary heart disease (CHD) risk in women. DESIGN--Prospective cohort study. SETTING--Female registered nurses in the United States. PARTICIPANTS--A total of 115,818 women aged 30 to 55 years in 1976 and without a history of previous CHD. MAIN OUTCOME MEASURE--Incidence of CHD defined as nonfatal myocardial infarction or fatal CHD. RESULTS--During 14 years of follow-up, 1292 cases of CHD were ascertained. After controlling for age, smoking, menopausal status, postmenopausal hormone use, and parental history of CHD and using as a reference women with a BMI of less than 21 kg/m2, relative risks (RRs) and 95% confidence intervals (CIs) for CHD were 1.19 (0.97 to 1.44) for a BMI of 21 to 22.9 kg/m2, 1.46 (1.20 to 1.77) for a BMI of 23 to 24.9 kg/m2, 2.06 (1.72 to 2.48) for a BMI of 25 to 28.9 kg/m2, and 3.56 (2.96 to 4.29) for a BMI of 29 kg/m2 or more. Women who gained weight from 18 years of age were compared with those with stable weight (+/- 5 kg) in analyses that controlled for the same variables as well as BMI at 18 years of age. The RRs and CIs were 1.25 (1.01 to 1.55) for a 5- to 7.9-kg gain, 1.64 (1.33 to 2.04) for an 8- to 10.9-kg gain, 1.92 (1.61 to 2.29) for an 11- to 19-kg gain, and 2.65 (2.17 to 3.22) for a gain of 20 kg or more. Among women with the BMI range of 18 to 25 kg/m2, weight gain after 18 years of age remained a strong predictor of CHD risk. CONCLUSIONS--Higher levels of body weight within the "normal" range, as well as modest weight gains after 18 years of age, appear to increase risks of CHD in middle-aged women. These data provide evidence that current US weight guidelines may be falsely reassuring to the large proportion of women older than 35 years who are within the current guidelines but have potentially avoidable risks of CHD.

Adult↗
PubMed1995

Controlled trial of fish oil for regression of human coronary atherosclerosis. HARP Research Group.

OBJECTIVES: This randomized clinical trial tested whether fish oil supplements can improve human coronary atherosclerosis. BACKGROUND: Epidemiologic studies of populations whose intake of oily fish is high, as well as laboratory studies of the effects of the polyunsaturated fatty acids in fish oil, support the hypothesis that fish oil is antiatherogenic. METHODS: Patients with angiographically documented coronary heart disease and normal plasma lipid levels were randomized to receive either fish oil capsules (n = 31), containing 6 g of n-3 fatty acids, or olive oil capsules (n = 28) for an average duration of 28 months. Coronary atherosclerosis on angiography was quantified by computer-assisted image analysis. RESULTS: Mean (+/- SD) baseline characteristics were age 62 +/- 7 years, plasma total cholesterol concentration 187 +/- 31 mg/dl (4.83 +/- 0.80 mmol/liter) and triglyceride levels 132 +/- 70 mg/dl (1.51 +/- 0.80 mmol/liter). Fish oil lowered triglyceride levels by 30% (p = 0.007) but had no significant effects on other plasma lipoprotein levels. At the end of the trial, eicosapentaenoic acid in adipose tissue samples was 0.91% in the fish oil group compared with 0.20% in the control group (p < 0.0001). At baseline, the minimal lumen diameter of coronary artery lesions (n = 305) was 1.64 +/- 0.76 mm, and percent narrowing was 48 +/- 14%. Mean minimal diameter of atherosclerotic coronary arteries decreased by 0.104 and 0.138 mm in the fish oil and control groups, respectively (p = 0.6 between groups), and percent stenosis increased by 2.4% and 2.6%, respectively (p = 0.8). Confidence intervals exclude improvement by fish oil treatment of > 0.17 mm, or > 2.6%. CONCLUSIONS: Fish oil treatment for 2 years does not promote major favorable changes in the diameter of atherosclerotic coronary arteries.

Adipose Tissue↗
PubMed1995

Micronutrients and HIV-1 disease progression.

OBJECTIVE: To determine whether nutritional status affects immunological markers of HIV-1 disease progression. DESIGN: A longitudinal study, to evaluate the relationship between plasma levels of nutrients and CD4 cell counts, along and in combination with beta 2-microglobulin (beta 2M; AIDS index) over an 18-month follow-up. METHODS: Biochemical measurements of nutritional status including plasma proteins, zinc, iron and vitamins B1, B2, B6, B12 (cobalamin), A, E, C and folate and immunological markers [lymphocyte subpopulations (CD4) and beta 2M] were obtained in 108 HIV-1-seropositive homosexual men at baseline and over three 6-month time periods. Changes in nutrient status (e.g., normal to deficient, deficient to normal), were compared with immunological parameters in the same time periods using an autoregressive model. RESULTS: Development of deficiency of vitamin A or vitamin B12 was associated with a decline in CD4 cell count (P = 0.0255 and 0.0377, respectively), while normalization of vitamin A, vitamin B12 and zinc was associated with higher CD4 cell counts (P = 0.0492, 0.0061 and 0.0112, respectively). These findings were largely unaffected by zidovudine use. For vitamin B12, low baseline status significantly predicted accelerated HIV-1 disease progression determined by CD4 cell count (P = 0.041) and the AIDS index (P = 0.005). CONCLUSIONS: These data suggest that micronutrient deficiencies are associated with HIV-1 disease progression and raise the possibility that normalization might increase symptom-free survival.

Adult↗
PubMed1995

Relationship of alcohol intake with blood pressure in young adults.

The objective of this study was to examine the relationship of usual current alcohol intake with systolic and diastolic pressures among young adults. Participants were 316 men and women, aged 18 to 26 years, from East Boston, Mass. At each of three weekly visits we obtained three blood pressure measurements on each subject using a random-zero sphygmomanometer. Using an interviewer-administered questionnaire, we obtained information about quantity and frequency of alcohol intake during the previous month. The lowest systolic pressure levels were in subjects consuming 1 to < 2 drinks per day. Adjusted for age, sex, and body mass index, systolic pressure was higher by 4.0 mm Hg (95% confidence interval [CI], 0.5 to 7.6 mm Hg) in abstainers, 3.6 mm Hg (95% CI, 0.5 to 6.6 mm Hg) in those who drank < 1 drink per day, 0.4 mm Hg (95% CI, -4.7 to 5.5 mm Hg) in those who drank 2 to < 3 drinks per day, and 8.1 mm Hg (95% CI, 2.9 to 13.4 mm Hg) in those who drank > or = 3 drinks per day. Levels of diastolic pressure were lowest in those consuming 2 to < 3 drinks per day. Adjustment for pulse rate, smoking, medication use, and family history of hypertension did not alter the results. These results suggest a J-shaped association of alcohol intake with blood pressure level in young adults, with the lowest levels in consumers of 1 to 3 drinks per day.

Adolescent↗
PubMed1995

Airway hyperresponsiveness to histamine associated with accelerated decline in FEV1.

An increased level of airway responsiveness has been proposed as a risk factor associated with the onset and prognosis of chronic airway obstruction. To determine this, longitudinal studies are necessary, with measurement of both the level of airway responsiveness and of additional risk factors, such as cigarette smoking, made before measurement of pulmonary function decline. The association of airways responsiveness with decline in FEV1 has been prospectively studied in a random sample of the Dutch population. Longitudinal data from 921 males, providing 2,376 paired observations, and 698 females, providing 1,682 paired observations, were used for analysis. Differences between responders and nonresponders (PC10 < or = 16 mg/ml of histamine) were estimated from linear regression analyses stratified by gender and smoking status, with adjustment for age, residential area, the presence of respiratory symptoms, indicators for each interval, and residuals of FEV1 at the beginning of the interval. Responders had a greater mean yearly decline in FEV1, and the differences between responders and nonresponders were similar for all gender and smoking subgroups. In an overall regression model, subjects with airway hyperresponsiveness had a significantly steeper decline in FEV1, independent of the other variables (males: beta = -12.5 ml/yr, SEM = 3.22, p < 0.001; females: beta = -11.50 ml/yr, SEM = 2.98, p < 0.001). The current analyses conclusively demonstrated that increased airway responsiveness is an independent risk factor for an accelerated decline in FEV1 and, hence, for the development of chronic obstructive lung disease. The mechanisms by which increased airway responsiveness leads to an accelerated decline in FEV, are imperfectly understood and require further study.

Adolescent↗
PubMed1995

A prospective study of diet and adult-onset asthma.

A role for diet in the pathophysiology of asthma may be mediated by altered immune or antioxidant activity with consequent effects on airway inflammation. We evaluated associations between several dietary factors assessed by a semiquantitative food frequency questionnaire, and incidence of asthma over a 10-yr period in 77,866 women 34 to 68 yr of age. Women in the highest quintile of vitamin E intake from diet, but not from supplements, had a risk of 0.53 (95% confidence interval [CI] = 0.33 to 0.86) compared with women in the lowest quintile. This relationship, however, was attenuated when the contribution from nuts, a major source of vitamin E in these data and a possible allergen, was removed (relative risk = 0.74 [0.50 to 1.10], p for trend = 0.007). Positive associations were found for vitamins C and E from supplements, but appeared to be explained by women at high risk of asthma initiating use of vitamin supplements prior to diagnosis. A nonsignificant inverse association with carotene intake was noted, but no clear relations with asthma were demonstrated for intake of linoleic acid or omega-3 fatty acids. These data suggest that antioxidant supplementation and intake of various fats during adulthood are not important determinants of asthma, although vitamin E from diet may have a modest protective effect.

Adult↗
PubMed1995

Menopause, postmenopausal estrogen preparations, and the risk of adult-onset asthma. A prospective cohort study.

We prospectively evaluated the association of hormone replacement therapy and asthma incidence in a cohort of pre- and postmenopausal women 34 to 68 yr of age. During 582, 135 person-years of follow-up between 1980 and 1990, 726 new cases of asthma were documented. Postmenopausal women who were never users of replacement hormones had a significantly lower age-adjusted risk of asthma than premenopausal women (relative risk = 0.65; 95% confidence interval [CI] = 0.46 to 0.92). Among naturally menopausal women, the age-adjusted relative risk of asthma for ever use of postmenopausal hormones was 1.49 (95% CI = 1.10 to 2.00); for current use of hormones (conjugated estrogens with or without progesterone), 1.50 (95% CI = 0.98 to 2.30); and for past use, 1.52 (95% CI = 1.08 to 2.13), compared with never use of hormones. Ever users of 10 or more years' duration had twice the age-adjusted risk of asthma compared with women who never used postmenopausal hormones (95% CI = 1.39 to 2.87). Among current users of conjugated estrogens, there was a positive dose-response demonstrated between daily dose and asthma risk (p for trend = 0.007). While confirmatory studies are warranted, these data suggest that estrogen plays a role in the pathophysiology of asthma and that long-term use and/or high doses of postmenopausal hormone therapy increase subsequent risk of asthma.

Adult↗
PubMed1995

Cigarette smoking and incidence of chronic bronchitis and asthma in women.

STUDY OBJECTIVE: To examine the relation of smoking habits and development of asthma in a large cohort of US women. DESIGN: Prospective cohort study. PARTICIPANTS: Among 74,072 women, 34 to 68 years of age, who were free of major diseases, we documented 671 incident asthma cases and 798 incident cases of chronic bronchitis during 10 years of follow-up. METHODS: Age-adjusted relative risk estimates for smoking categories were calculated separately for chronic bronchitis and asthma. RESULTS: Risk of chronic bronchitis was significantly higher in current smokers than in never smokers (relative risk [RR] = 2.85; 95% confidence interval [CI] = 2.45 to 3.32) and increased with the number of cigarettes smoked per day (p for trend < 0.0001). Approximately 5 years after quitting, chronic bronchitis risk in past smokers approached that in never smokers. In contrast, current smokers were at significantly lower risk for asthma than women who never smoked (RR = 0.57; 95% CI = 0.46 to 0.71) and women who quit (RR = 0.50; 95% CI = 0.40 to 0.62), possibly because individuals with sensitive airways are less likely to become regular smokers, and smokers who develop respiratory symptoms of any etiology tend to quit. Asthma risk in past smokers initially increased compared with that in never smokers, possibly because of quitting prior to diagnosis in response to symptoms of any etiology, but decreased with time since quitting (p for trend = 0.007); within approximately 5 years, the risk did not differ between past and never smokers. CONCLUSION: These data suggest that smoking in adults may not be an independent cause of asthma but could exacerbate or be perceived as exacerbating asthma symptoms in susceptible individuals.

Adolescent↗
PubMed1995

Red blood cell membrane phosphatidylethanolamine fatty acid content in various forms of retinitis pigmentosa.

In order to test the hypothesis that retinitis pigmentosa (RP) is associated with fatty acid abnormalities within cell membrane phospholipids, red blood cell membrane (RBC) phosphatidylethanolamine (PE) fatty acid content (% of total fatty acids) was measured using high performance liquid chromatography and capillary column gas chromatography in 155 patients from separate families with different genetic types of RP and 101 normal subjects. After controlling for the effects of age and sex, patients with all genetic forms of RP had significantly (P < 0.001) reduced mean RBC PE 22:6 omega 3 (n-3) (docosahexaenoic acid, DHA) content, and significantly (P < 0.001) elevated mean RBC PE dimethyl acetal (DMA) forms of 16:0, 18:0, and 18:1 omega 9 (n-9) as compared with normal subjects. RBC PE content of 22:5 omega 3 (n-3) (a precursor to DHA) and 18:2 omega 6 (n-6) (the major dietary essential fatty acid) were not significantly different in RP than in controls. Analysis by genetic types of RP showed that the mean RBC PE DHA percentages were significantly reduced by 24%, 14%, 30%, and 17%, respectively, in dominant, recessive, X-linked, and isolate forms of RP. The relative amounts of plasmalogens as indicated by DMA forms of 16:0 and 18:0 were significantly (P < 0.01) increased in dominant (by 33% and 25%), recessive (by 36% and 25%), and isolate cases (by 32% and 26%) of RP as compared with normal subjects. No such differences were seen in X-linked cases versus controls. Our data indicate that RBC PE DHA content is decreased in all genetic types of RP patients as compared to control subjects, and that RBC PE plasmalogens are increased in dominant, recessive, and isolate forms of RP. These data raise the possibility that membrane phospholipid fatty acid abnormalities may contribute to the pathogenesis of RP.

Acetals↗
PubMed1994

Effect on coronary atherosclerosis of decrease in plasma cholesterol concentrations in normocholesterolaemic patients. Harvard Atherosclerosis Reversibility Project (HARP) Group.

Lipid-lowering therapy ameliorates coronary atherosclerosis in patients with raised concentrations of low-density-lipoprotein (LDL) cholesterol. We have investigated whether a similar benefit can be obtained in normocholesterolaemic patients. We studied 79 normocholesterolaemic patients with coronary heart disease (70 male, 9 female), mean age 58 years, all non-smokers, with mean total cholesterol concentration 5.5 mmol/L. All patients received diet therapy and were randomly assigned placebo (39) or active treatment (40) with pravastatin, nicotinic acid, cholestyramine, and gemfibrozil stepwise as needed to reach the specified goal (total cholesterol < or = 4.1 mmol/L, ratio of LDL/high-density-lipoprotein [HDL] cholesterol < or = 2.0). Coronary angiograms at baseline and after 2.5 years of treatment were analysed by computer-assisted quantitative techniques. There was no significant difference in coronary atherosclerosis during follow-up between the active treatment and placebo groups; the mean minimum diameter narrowed significantly but to the same extent in both groups (change baseline to 2.5 years 0.14 [SD 0.42] and 0.15 [0.42] mm, respectively, both p < 0.001). Similarly, the change in percentage stenosis did not differ between the groups (2.1 [10.6] vs 2.4 [10.3]%). By multiple regression analysis, the adjusted difference between the groups was a 0.04 mm (95% CI -0.04 to 0.12 mm) increase in minimum diameter and a 0% (-1.7 to 1.7) change in percentage stenosis. The groups differed significantly in plasma lipids (% change in active minus % change in placebo group: -28% total cholesterol, -41% LDL-cholesterol, 13% HDL-cholesterol, -26% triglycerides, -31% apolipoprotein B, all p < 0.001). Thus, intensive pharmacological treatment of normocholesterolaemic patients has significant effects on plasma lipid concentrations but no angiographically measurable benefit on the coronary arteries.

Anticholesteremic Agents↗
PubMed1994

Comparison of alternative regression models for paired binary data.

We used simulated data, derived from real ophthalmologic examples, to evaluate the performance of alternative logistic regression approaches for paired binary data. Approaches considered were: standard logistic regression (ignoring the correlation between fellow eyes, treating individuals classified on the basis of their more impaired eye as the unit of analysis, or considering only right eyes); marginal logistic regression models fitted by the maximum likelihood approach of Lipsitz, Laird and Harrington or the estimating equation approach of Liang and Zeger; and conditional logistic regression models fitted by the maximum likelihood approach of Rosner or the estimating equation approach of Connolly and Liang. Taylor series approximations were used to compare conditional and marginal parameter estimates. Consideration of type I and II error rates found application of standard logistic regression to be inferior to methods that treated the eye as the unit of analysis and accounted for the correlation between fellow eyes. Among these latter approaches, none was uniformly superior to the others across the range of condition considered.

Age Factors↗
PubMed1994

Reproductive risk factors in a prospective study of breast cancer: the Nurses' Health Study.

A modification of the model of Pike et al. (Nature 1983;303: 767-70) was applied to 91,523 women in the Nurses' Health Study who did not report prevalent cancer initially and who were followed for 14 years (1,212,855 person-years and 2,341 incident breast cancers). The model took into account current age, age at all births, age at menopause, and age at menarche in predicting the annual and cumulative incidence of breast cancer. The authors found that ages both at first birth and at subsequent births have long-term influence on breast cancer incidence. The incidence density for parous women was greater than for nulliparous women for 20-30 years after the time of the first birth. However, cumulative incidence up to age 70 years was about 20% lower, 10% lower, or 5% higher for parous versus nulliparous women if their first birth was at age 20, 25, or 35 years, respectively. The authors also observed a significantly lower incidence after each additional birth as well as after menopause for women of the same age. Overall, the effect of reproductive factors (other than age at menarche) appears to influence cumulative incidence to age 70 years by a maximum of approximately 50% when women with multiple births with an early age at first birth are compared with women with a single birth at a late age.

Adult↗
PubMed1994

Smoking cessation and time course of decreased risks of coronary heart disease in middle-aged women.

BACKGROUND: We examined prospectively the relation of time since stopping smoking with risk of coronary heart disease in middle-aged women. METHODS: The study was based on 12 years' follow-up data (1976 through 1988) from the Nurses' Health Study, an ongoing prospective cohort study, in which information on smoking habits was updated every 2 years by a mailed questionnaire. The study population consisted of 117,006 female registered nurses aged 30 to 55 years in 1976 who were free of coronary heart disease, stroke, and cancer at baseline. The outcome measure used was incident coronary heart disease, defined as nonfatal myocardial infarction plus fatal coronary heart disease. RESULTS: A total of 970 incident cases of coronary heart disease (215 among participants who never smoked, 214 among former smokers, and 541 among current smokers) occurred during 1.37 million person-years of follow-up. The multivariate relative risk of total coronary heart disease among current smokers compared with participants who never smoked was 4.23 (95% confidence interval, 3.60 to 4.96). Risk of coronary heart disease was highest among smokers who started smoking before the age of 15 years (relative risk, 9.25; 95% confidence interval, 5.27 to 16.23). The relative risk among former smokers was 1.48 (95% confidence interval, 1.22 to 1.79). On stopping smoking, one third of the excess risk of coronary heart disease was eliminated within 2 years of cessation. Thereafter, the excess risk returned to the level of those who never smoked during the interval 10 to 14 years following cessation. CONCLUSION: Women who stop smoking will experience an immediate benefit as well as a further longer-term decline in excess risk of coronary heart disease to the level of those who never smoked.

Adult↗
PubMed1994

Reproducibility and validity of a self-administered physical activity questionnaire.

BACKGROUND: The reproducibility and validity of self-administered questionnaires on physical activity and inactivity were examined in a random (representative) sample of the Nurses' Health Study II cohort and a random sample of African-American women in that cohort. METHODS: Repeat questionnaires were administered 2 years apart. Past-week activity recalls and 7-day activity diaries were the referent methods; these instruments were sent to participants four times over a 1-year period. RESULTS: The 2-year test-retest correlation for activity was 0.59 for the representative sample (n = 147) and 0.39 for the African-American sample (n = 84). Correlations between activity reported on recalls and that reported on questionnaire were 0.79 and 0.83 for the representative and African-American samples, respectively. Correlations between activity reported in diaries and that reported on questionnaire were 0.62 and 0.59, respectively. Test-retest coefficients for inactivity were 0.52 and 0.55, respectively. Correlations between inactivity reported in diaries and that reported on questionnaire were 0.41 and 0.44, respectively. CONCLUSION: The simple, short questionnaires on activity and inactivity used in the Nurses' Health Study II are reasonably valid measures for epidemiological research.

Adult↗