This population-based case-control study assessed the effect of current use of monophasic or triphasic oral contraceptives (OCs) on the risk of functional ovarian cyst development. The cases were all ...15-39-year-old enrollees in the Group Health Cooperative of Puget Sound who had either an inpatient primary diagnosis of functional ovarian cyst in 1988 or 1989 (N = 67) or an outpatient primary diagnosis of functional ovarian cyst from March 1988 through August 1989 at one of five Group Health Cooperative primary care clinics (N = 39). Controls were randomly selected enrollees matched to the cases for age, primary care clinic, and enrollment date (N = 255). Subjects with previous hysterectomy or oophorectomy were excluded from this analysis. Pharmacy and medical record review showed that 16% of cases and 19% of controls were currently using monophasic OCs, whereas 11% of cases and 9% of controls were using triphasic OCs. Compared with women not using hormonal contraception, the relative risks of a diagnosed functional ovarian cyst among women currently using OCs were 0.8 (95% confidence interval CI 0.4-1.8) for users of monophasic OCs and 1.3 (95% CI 0.5-3.3) for users of triphasic OCs. In contrast to previous studies of monophasic OCs containing higher steroid dosages, the results of this study suggest that current use of low-dose monophasic OCs does not substantially decrease a woman's risk of functional ovarian cyst formation. In addition, our results do not support recent speculation that current use of triphasic OCs appreciably increases the risk of functional ovarian cysts.
Data from a population-based case-control study conducted in Washington State and Utah were used to assess whether obesity is associated with an altered risk of epithelial ovarian cancer. Quetelet ...index, defined as weight (kg) at age 30 years divided by height (m) squared, was calculated for each woman, and the values for all subjects were divided into five categories of approximately equal size. Compared with women in the lowest category, women in the highest category had an odds ratio of 1.7 (95 per cent CI 1.1-2.7). Risks for women in the three intermediate Quetelet index categories also exceeded the risk for women in the lowest group, but to a much smaller degree. Among women with serous tumors, those in the highest Quetelet index category were at a greater than twofold excess risk (OR = 2.2, 95 per cent CI 1.1-4.2), but the risk was not increased in the intermediate categories. For endometrioid tumors, risk increased consistently with increasing Quetelet index, and the odds ratio in the highest category was 4.7 (95 per cent CI 1.0-22.7). For both serous and endometrioid tumors, the excess risk was largely confined to premenopausal women. The results of this analysis suggest that for at least some types of ovarian tumor, obesity may warrant further attention as a possible etiologic factor.
We interviewed 327 women who had been 50 to 74 years of age when treated for fracture of the hip of lower forearm, to determine their use (or lack of use) of estrogen preparations. Their responses ...were compared with those in a random sample of 567 women who were of similar age and from the same region. The risk of fracture was 50 to 60 per cent lower in women who had used these drugs for six years or longer than in women who hadnot used them (95 per cent confidence interval of relative risk, 0.3 to 0.6); those using them for shorter periods received less benefit, if any. A decreased risk of fracture was clearly evident only in women still taking estrogens and evident at either common daily dose (0.625 and 1.25 mg). In conjunction with the finding that estrogens can retard the development of osteoporosis in postmenopausal women, our data argue that lowering of the risk of hip and forearm fractures must be weighed as a benefit of long-term estrogen use.
Electric blankets are an important domestic source of electromagnetic fields (EMF) because of the relatively high intensity of emission, prolonged exposure, and intimate contact with the source. In a ...case-control study of testicular cancer in western Washington during 1981 to 1984, the relation between EMF exposure from electric blankets and the occurrence of testicular cancer was examined. The respective proportions of cases and controls who reported the use of an electric blanket were almost identical (age-adjusted rate ratio (RR) = 1.0, 95% confidence interval (CI) 0.7-1.4). Distributions of the duration of use were also very similar in cases and controls. Compared with controls, the frequency of use of an electric blanket was slightly lower in men with seminoma (RR = 0.7, 95% CI 0.5-1.2) and slightly higher among men with nonseminoma germ cell tumors (RR = 1.4, 95% CI 0.9-2.3). Overall, the results of this study suggest that increased exposure to EMF from electric blankets contributes little, if at all, to the risk of testicular cancer in adult white men.
Recreational drug (marijuana, lysergic acid diethylamide or LSD, speed, cocaine, and "other") exposures of women with primary infertility were compared with those of a matched control group of women ...with proven fertility. Women who reported smoking marijuana had a slightly elevated risk for infertility due to an ovulatory abnormality (RR = 1.7, 95% CI = 1.0 to 3.0). The risk was greatest among women who had used marijuana within one year of trying to become pregnant (RR = 2.1, 95% CI = 1.1 to 4.0). No consistent frequency or duration of use effects could be demonstrated, and the risk was confined to low-frequency users. Risks associated with the use of other drugs were not elevated. The risk of infertility from a tubal abnormality associated with cocaine use was greatly increased (RR = 11.1, 95% CI = 1.7 to 70.8). Our results are consistent with animal studies suggesting that smoking marijuana may cause a transient disruption of ovulatory function. The possibility that cocaine exposure influences the development of tubal infertility needs further investigation.
This population-based case-control study examined the risk of multiple myeloma in relation to socioeconomic status. Subjects included 689 cases with newly diagnosed multiple myeloma during 1977-1981 ...from four U.S. populations and 1,680 controls selected from residents of these same populations. We collected lifetime occupational histories and coded them according to the 1970 Duncan Socioeconomic Index and Nam-Powers Socioeconomic Status scores. We classified scores for the occupations held the longest, highest ever held, and held most recently into quartiles based on the distribution among controls. After adjusting for age group, race, and study site, risk of multiple myeloma was inversely associated with socioeconomic status scores in both men and women. Risk among persons in the lowest quartile of scores was 63% higher (95% confidence interval 21%-119%) than that among those in the highest quartile when the highest Nam-Powers score was used. Similar trends were evident for all three methods of classifying occupational history and for both Duncan and Nam-Power scores. These results changed little after removing from analyses occupations previously associated with increased risk. The occupation-based scores were stronger predictors of risk than years of education. As a proxy measure of occupational, environmental, or life-style factors, socioeconomic status may be a clue to etiologic factors for multiple myeloma.
Risk factors for hip fracture among patients with end-stage renal disease.
Although bone disease is well described among end-stage renal disease (ESRD) patients, little attention has been paid to the ...occurrence of fracture. We sought to identify factors that are associated with hip fracture among ESRD patients.
Data from patients who participated in the United States Renal Data System Dialysis Morbidity and Mortality Study Wave 1 were used for this study. Hip fractures occurring among these patients between 1993 and 1996 were identified from Medicare claims data available from the United States Renal Data System. Cox proportional hazards models were used to estimate the risk of hip fracture associated with demographic and medical variables.
Of the 4952 patients included in this analysis, 103 sustained a hip fracture. In the multivariate analysis, age (per increasing decade, RR = 1.40, 95% CI 1.20, 1.64), female gender (RR = 2.26, 95% CI 1.48, 3.44), race (blacks compared with whites, RR = 0.58, 95% CI 0.37, 0.91), body mass index (per 1 unit increase, RR 0.89, 95% CI 0.86, 0.93), and the presence of peripheral vascular disease (RR 1.94, 95% CI 1.29, 2.92) were independently associated with hip fracture. Serum intact parathyroid hormone (iPTH), aluminum, diabetes, and bicarbonate levels did not appreciably influence the risk of hip fracture.
Demographic and other characteristics that predict risk of hip fracture in the population at large also do so in ESRD patients. However, we could identify no characteristics of ESRD or its treatment that were independently related to hip fracture incidence.
PDF
