Myocardial Infarction and Non-contraceptive Estrogen Use

BACKGROUND:

The use of noncontraceptive estrogens declined after evidence was published that they increase the risk of endometrial cancer. Nonetheless, they are still used commonly and for long periods, especially by hysterectomized women. Use of the drugs has increased recently, perhaps because the drugs have been recommended as prophylaxis against osteoporosis. The drugs are also being promoted for use in conjunction with a progestin, because it is thought that the combination may protect against endometrial cancer. Little is known about the effects of these drug regimens on myocardial infarction risk, and some progestins (in particular the 19-norprogestins) are thought to influence lipid profiles unfavorably. Insofar as myocardial infarction is a major cause of morbidity and mortality in women beyond age 49, an effect of these drugs, either beneficial or adverse, on myocardial infarction risk is of considerable public health importance.

DESIGN NARRATIVE:

The design was that of a case-control study. Cases were selected from women admitted for the first episode of myocardial infarction to any of the participating hospitals in the Boston area. For each case, a control was selected from town lists of women living in the same neighborhood as the case and in the same five year age group. Cases were interviewed by telephone after discharge from the hospital, and the corresponding control was interviewed within a week or two of the case interview.

Information was obtained on: the timing and duration of non-contraceptive estrogen use, the names of the preparations and reasons for starting and stopping each episode of use; other drug use particularly oral contraceptives, aspirin, phenylpropanolamine; age at menopause; cigarette smoking; height and weight; histories of previous myocardial infarction, hypertension, pre-eclamptic toxemia, diabetes mellitus, angina pectoris and abnormal serum lipids; reproductive history; alcohol and coffee consumption; personality type based on the Framingham Type A Scale; family history of myocardial infarction; exercise; socioeconomic and life style factors; number of physician visits in last two years and total number of hospital admissions.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.