Long-term prognostic role of functional limitations among women with breast cancer

Abstract

Background The long-term prognostic role of functional limitations among women with breast cancer is poorly understood. Methods We studied a cohort of 2202 women with breast cancer at two sites in the United States, who provided complete information on body functions involving endurance, strength, muscular range of motion, and small muscle dexterity following initial adjuvant treatment. Associations of baseline functional limitations with survival were evaluated in delayed entry Cox proportional hazards models, with adjustment for baseline sociodemographic factors, body mass index, smoking, physical activity, comorbidity, tumor characteristics, and treatment. Difference in covariates between women with and without limitations was assessed with Pearson χ 2 and Student t tests. All statistical tests were two-sided. Results During the median follow-up of 9 years, 112 deaths were attributable to competing causes (5% of the cohort) and 157 were attributable to breast cancer causes (7% of the cohort). At least one functional limitation was present in 39% of study participants. Proportionately, more breast cancer patients with functional limitations after initial adjuvant treatment were older, less educated, and obese (P