Assessment of the effects of severe obesity and lifestyle risk factors on stage of endometrial cancer

Abstract

Background: Lifestyle risk factors, including obesity, have been associated with increased risk of endometrial cancer (EC). Women with higher obesity levels tend to have less aggressive EC disease stage and histology. This study further investigated associations between nonmodifiable risk factors, such as age, race, and grade, and modifiable lifestyle factors, such as diet and physical activity expenditure, in relation to severe obesity and late versus early EC stage at diagnosis. Methods: Demographic, anthropometric, and lifestyle surveys were administered to 177 women with histologically confirmed EC. Logistic regression analyses assessed the relationship between obesity and other risk factors on EC stage at diagnosis. Results: In multivariate models, body mass index (BMI) < 35 was not significantly associated with late EC stage at diagnosis (OR = 1.67, P = 0.219) when adjusting for grade and age. Grade was significantly associated with EC stage when controlling for BMI and age (OR = 8.48, P = .000). Women more than the age of 60 had a fourfold increased risk of diagnosis at late versus early EC stage when adjusting for other risk factors. Age had a confounding effect on the obesity-EC stage association. Conclusions: Our results corroborate those of past studies showing that BMI is not an independent risk factor for EC stage and that age may have confounded the obesity-EC stage association. Because of mixed results and implications for treatment outcomes, however, further research examining these variables is warranted. Impact: Our results provide further insight into the obesity EC-stage association, especially the confounding effect of age. Future studies should examine modifiable lifestyle factors in larger and more diverse populations. ©2012 AACR.