Epidemiological analysis of obesity-related comorbidities and mortality among postmenopausal women with endometrial cancer: Findings from the Women’s Health Initiative randomized controlled trials and observational study

Introduction: Obesity is a well-established risk factor for endometrial cancer (EC). Postmenopausal women with EC frequently present with obesity-related comorbidities or develop them after diagnosis, which may impact survival. Objectives: This study aimed to identify modifiable comorbidities (diabetes, cardiovascular disease, hypertension, and fractures) among postmenopausal EC survivors and evaluate the relationship between obesity-related comorbidities and all-cause mortality after an EC diagnosis. Design: Prospective cohort analysis of overall mortality risk in relation to obesity-related comorbidities in women diagnosed with EC. Population and Setting: Postmenopausal women recruited across 40 clinical sites within the Women’s Health Initiative (WHI) observational and clinical trials and experiencing a new diagnosis of EC. Methods: Adjusted Cox proportional hazards regression models were used to evaluate the relationship between comorbidities and all-cause mortality among women with incident EC. Results: A total of 1,661 incident cases of EC were identified. The overall mortality rate was 55.5%. The prevalence of each comorbidity increased from baseline to 18 years of follow-up. Regression analyses for incident EC indicated that severe obesity (hazard ratio [HR] = 2.13; 95% confidence interval [CI]: 1.52–2.97), cardiovascular disease (HR = 1.50; 95% CI: 1.26–1.78), and fracture (HR = 1.17; 95% CI: 1.07–1.27) were associated with greater overall mortality. Conclusion: Obesity-associated comorbidities are common and associated with higher mortality in postmenopausal women diagnosed with EC. Interventions to reduce the risk of comorbidity among EC survivors may improve survival and should be evaluated (ClinicalTrial.gov identifier: NCT00000611).