Obesity, diabetes, and other factors in relation to survival after endometrial cancer diagnosis

Endogenous and exogenous sources of estrogen and characteristics altering these hormone levels have been related to endometrial cancer risk; however, their relationship to survival following diagnosis is less clear. In a population‐based study, we examined whether mortality after endometrial cancer diagnosis was affected by prediagnosis obesity, diabetes, smoking, oral contraceptive use, parity, or postmenopausal hormone (PMH) use. Eligible women, aged 40–79 years, diagnosed from 1991–1994 with incident invasive endometrial cancer and identified through the Wisconsin statewide mandatory cancer registry were invited to participate. Of 745 eligible cases, 166 women were deceased after 9.3 years of follow‐up, with 43 attributable to endometrial cancer, based upon vital records linkage. Hazard rate ratios (HRR) and 95% confidence intervals were adjusted for age at diagnosis, menopausal status, stage of disease, and other exposures of interest. Obese women (body mass index [BMI] ≥30 kg/m2) prior to endometrial cancer diagnosis had an increased risk of both all‐cause (HRR = 1.6, 95% CI 1.0–2.5) and endometrial cancer (HRR = 2.0, 95% CI 0.8–5.1) mortality, compared with nonoverweight women (BMI < 25 kg/m2). Endometrial cancer cases with diabetes also had an increased risk of all‐cause mortality compared with nondiabetic women (HRR = 1.7, 95% CI 1.1–2.5), although there was no association with endometrial cancer mortality. There were no associations between PMH use, oral contraceptive use, parity, or smoking and mortality from any cause. The results suggest that history of obesity and diabetes may increase risk of mortality after endometrial cancer diagnosis; modification of these characteristics may improve survival after endometrial cancer diagnosis.