Obesity, estrone, and coronary artery disease in postmenopausal women

The link between obesity and endogenous estrogen with coronary artery disease (CAD) in postmenopausal women is uncertain. In this prospective study we analyzed the association of body mass index (BMI) and blood levels of estrone in postmenopausal women with known CAD or with a high risk factor score for CAD.

Participants were 251 female clinic patients aged 50-90 years who were postmenopausal and not using estrogen therapy. Clinical and behavioral characteristics and fasting blood for estrone and heart disease risk factors were collected at baseline, and again at 1 and 2 years. Women were grouped according to their BMI (kg/m2) as normal (18.5< or =BMI<25), overweight (25< or =BMI<30) or obese (BMI > or =30), and by low and high estrone levels (<15 and > or =15pg/mL, respectively). Fatal and nonfatal events were recorded for 2 years after baseline.

Women with a low estrone level were older, thinner, and had less hypertension, diabetes, and lower triglyceride and glucose levels. BMI was positively associated with estrone levels, hypertension, and diabetes and inversely associated with HDL cholesterol. There were 14 deaths, 8 attributed to CAD. The Kaplan-Meier survival curve showed a nonsignificant trend (p=0.074) of greater all cause mortality in women with low estrone levels (<15mL). In this model, adjusted for BMI, age [OR=1.08; p=0.03], C-reactive protein [OR=1.24; p=0.024] and hypertension [OR=6.22; p=0.003] were independent predictors of all cause mortality.

Postmenopausal women with low estrone levels (<15pg/mL) had a trend for increased mortality over the next 2 years. Larger, longer studies are needed.