All cases of endometrial cancer occurring among the residents of an affluent retirement community were compared with controls chosen from a roster of all women in the same community. Evidence of estrogen and other drug use and of selected medical conditions was obtained from three sources: medical records of the principal care facility, interviews, and the records of the local pharmacy. The risk ratio for any estrogen use was estimated from all available evidence to be 8.0 (95 per cent confidence interval, 3.5 to 18.1). and the for conjugated estrogen use to be 5.6 (95 per cent confidence interval, 2.8 to 11.1). Increased risk from estrogens was shown for invasive as well as noninvasive cancer, and a dose-response effect was demonstrated. For an estrogen user, the risk from endometrial cancer appeared to exceed by far the base-line risk from any other single cancer.

To determine whether the association with vasectomy might have a hormonal basis, we compared levels of testosterone (T) and testosterone binding globulin-binding capacity (TeBG-bc) in 33 of the vasectomized control men with levels in 33 non-vasectomized controls of the same age, weight and height. T levels were higher in vasectomized than in non-vasectomized controls (1-sided P=0.06). The ratio of T to TeBG-bc (an index of bioavailable T) was 13.5% higher in vasectomized men (1-sided P=0.03).

The association between menopausal estrogen therapy and hip fracture was studied in a retirement community. Ninety-one hip fracture cases during a 5-year period in female residents under age 80 were compared to age-and race-matched community controls. Estrogen use was recorded from the medical records of the outpatient care facility and personal interviews. The estimated risk ratio for use of oral estrogens in excess of 60 months was 0.42. This protective effect was largely limited to oophorectomized women for whom the risk ratio for a comparable duration of use was 0.14; the risk significantly decreased with increased duration, but no such trend existed with increased dosage. Diabetes mellitus, low Quetelet's index, tallness, prolonged immobilization or physical inactivity, use of corticosteroids, early age at menopause, low levels of sunlight exposure, and heavy cigarette smoking were each independent risk factors for hip fracture but none confounded the observed association with estrogen use.

No abstract

In an attempt to confirm three reports suggesting a causal link between rauwolfia antihypertensive drugs and female breast carcinoma, all cases of such cancer appearing among the residents of an affluent retirement community were compared with controls chosen from a roster of all women in the same community. Most residents use a single care facility, and patterns of hypertension diagnosis, rauwolfia and other drug use, and medical-care-system patronage were abstracted from medical records. The prevalence of recorded rauwolfia use among the controls were 20 per cent, and that of other drug use was correspondingly high. The risk ratio for rauwolfia use was estimated to be 1.2 (95 per cent confidence interval, 0.7 to 2.2). Risk ratios between 1.0 and 2.0 were also found for other drug use and for measures of care-system patronage. These results do not support the hypothesis that reserpine causes breast cancer.