ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

To compare the efficiency of male-to-female and female-to-male sexual transmission of human immunodeficiency virus (HIV), we studied 524 female partners of HIV-infected men and 206 male partners of HIV-infected women in 16 Italian clinical centers. All of the partners had had a sexual relationship with the index case lasting for at least 6 months and presented no other risk factor than sexual exposure to the HIV-infected partner. Among the 730 couples, 24% of the female partners were HIV positive, in comparison with 10% of the male partners. Using logistic regression analysis, including gender and controlling for condom use, frequency of intercourse, anal sex, partner's CD4+ cell count and clinical stage, sexually transmitted diseases, genital infections, and contraceptive use, we found that the efficiency of male-to-female transmission was 2.3 (95% confidence interval = 1.1–4.8) times greater than that of female-to-male transmission. Between-gender differences in the contact surfaces and the intensity of exposure to HIV during sexual intercourse are possible reasons for the difference in efficiency of transmission. (Epidemiology 1994;5:570–575)

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The positive association between alcohol consumption and blood pressure is well known. Little is known, however, about effect modification by age, gender, and smoking on the alcohol-blood pressure association. We used data of a cross-sectional study conducted in the Netherlands to investigate the association between alcohol consumption and blood pressure. Between 1987 and 1990, we examined about 30,000 men and women age 20–59 years. After adjustment for age, body mass index, and smoking, we found that in men systolic and diastolic blood pressure increased by 0.9 and 0.6 mmHg per daily drink, respectively. In women, systolic and diastolic blood pressure were 2 and 1 mmHg higher in those who consumed 2 or more glasses per day compared with nondrinkers, respectively. We observed a stronger association between alcohol and blood pressure in older men compared with younger men and in male and female smokers compared with nonsmokers. These data show that gender, age, and smoking all are important effect modifiers of the alcohol-blood pressure relation.

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Consumption of maté, a tea-like infusion of the herbIlex paraguariensis, is common in South America. Drinkers have high risks of upper aerodigestive tract cancers, but it is conceivable that this high risk may be attributable to confounding by smoking, alcohol other exposures. To test this hypothesis, we analyzed the data from a case-control study of upper aerodigestive tract cancers conducted in Southern Brazil. We matched noncancer controls (N = 756) to cases (N = 378) on the basis of age, sex period of admission. We estimated the effect of maté consumption by conditional logistic regression with adjustment for smoking, alcohol, sociodemographics several dietary items, considered as confounders. The unadjusted relative risk (RR) for all upper aerodigestive tract cancers was 2.1 [95% confidence interval (CI) = 1.6–2.7]. Some excess risk persisted after adjustment for potential confounders (RR = 1.6; 95% CI = 1.2–2.2). Most of the excess risk for maté drinkers was for oral (RR = 1.9; 95% CI = 1.1–3.3) and laryngeal (RR = 2.2; 95% CI = 1.1–4.5) cancers. There was no evidence of associations with coffee and tea drinking. We conclude that the association of maté consumption with upper aerodigestive tract cancer risk is unlikely to result from insufficient control of confounding by critical exposures. Owing to its high prevalence in Southern South America, maté drinking may be linked to as many as 20% of all cases occurring in this region.

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Older drivers have the second highest risk for motor vehicle collisions of any age group, after adolescents. Psychoactive medications may place older drivers at increased risk for injurious motor vehicle collisions. We conducted a population-based matched case-control study of older drivers who were involved in injurious crashes during 1987 and 1988. The 234 cases and 447 controls were members of a large Seattle-based health maintenance organization. Use of antidepressants and opioid analgesics by older drivers was associated with increased risk for injurious motor vehicle collisions. Compared with non-users, current users of cyclic antidepressants had an adjusted relative risk (RR) of 2.3 [95% confidence interval (CI) = 1.1–4.8]. Opioid analgesic use was also associated with an elevated crash risk (adjusted RR = 1.8; 95% CI = 1.0–3.4). We found no evidence of a doserelated effect with either class of drug. Current use of benzodiazepines or sedating antihistamines had little association with increased risk for injurious collisions. (Epidemiology 1994;5:591–598)

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The objective of this study was to determine the effects of age and life-style factors on body mass index (BMI) in a longitudinal, community-based sample. A total of 568 men and 668 women (20–60 years of age) were randomly chosen from four Northern California communities and followed for up to 7 years. Age, sex, marital status, smoking status, hours of television watched, frequency of consumption of several food items physical activity were used to predict rate of change of body mass index (BMI-slope). BMI increased the most for both sexes through at least age 54. The BMI-slope was higher for women compared with men for smokers who stopped compared with those who never smoked or continued to smoke during the study. The BMI-slopes were lower for individuals who increased activity. Other life-style variables had weak or inconsistent effects on the BMI-slope. We conclude that the BMI-slope increases over age for both sexes and that increased physical activity may reduce the BMI-slope. (Epidemiology 1994;5:599–603)

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

We examined the relation between breast cancer, parity age at first and last births in a large national cohort of young women in Norway. We estimated relative incidence rates by Poisson regression analyses of person-years at risk with parity and age at last (most recent) birth as time-dependent variables. A total of 1,071,795 women were included in follow-up, contributing a total of 16,643,883 person-years in the age range 20–54 years. Follow-up times ranged from 1 month to 34.5 years. A total of 4,302 women were diagnosed with breast cancer during follow-up. With adjustment for age at first and last births, high parity was associated with an overall reduced risk of breast cancer (incidence rate ratio = 0.46; 95% confidence interval = 0.36–0.59 for women with five or more children vs uniparous women). Among women age 20–29 years, however, the results suggested an increase in risk with increasing parity (incidence rate ratio = 1.25; 95% confidence interval = 0.64–2.45 for women with three children vs uniparous women). The protective effect of high parity was particularly strong among women with first birth before the age of 20 years and rather weak among those with first birth at age 30 years or more. Low ages at first and last births were both associated with reduced breast cancer risk in analyses with adjustment for the other factor, with the association with age at last birth being slightly stronger. (Epidemiology 1994;5:604–611)

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Hierarchical regression attempts to improve standard regression estimates by adding a second-stage “prior” regression to an ordinary model. Here, we use hierarchical regression to analyze case-control data on diet and breast cancer. This regression yields semi-Bayes relative risk estimates for dietary items by using a second-stage model to pull estimates toward each other when the corresponding variables have similar levels of nutrients. Unlike classical Bayesian analysis, however, no use is made of previous studies on nutrient effects. Compared with results obtained with one-stage conditional maximum-likelihood logistic regression, our hierarchical regression model gives more stable and plausible estimates. In particular, certain effects with implausible maximum-likelihood estimates have more reasonable semi-Bayes estimates. (Epidemiology 1994;5:612–621)

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

The epidemiologic utility of mapping and ranking incidence rates is often questioned owing to instability of the observed incidence values in areas with small populations. Spurious fluctuations in the observed rates caused by this instability can mask true spatial and temporal trends in risk. To produce maps with the required level of geographic resolution, yet based on reliable estimates, it is desirable to reduce the random variation in the observed rates before mapping. In this paper, we describe the empirical Bayes approach for obtaining stabilized incidence estimates. We begin by deriving Bayes rate estimators and then illustrate how using the observed rates to estimate unknown distributional information leads to the empirical Bayes formulation. A drawback of the approach is that the histogram of the empirical Bayes rate estimates may be narrower than the true distribution of risk. We outline a constrained empirical Bayes approach that produces improved estimators for the true distribution of the unknown rates. We include discussions of relevant previous applications of empirical Bayes methods to rate mapping problems and an evaluation of the strengths and weaknesses of the approach. (Epidemiology 1994;5:622–630)

ISSN:1044-3983    

出版商:OVID    

年代:1994

数据来源: OVID