BACKGROUND: Breast cancer is the leading cause of cancer mortality among women, with an estimated 43,700 deaths in the US in 2023. Clinical factors, such as higher stage, greater lymph node involvement, and poor treatment adherence are known to influence survival; however, less is known about the effects of lifestyle factors at diagnosis, such as physical activity (PA). According to the American College of Sports Medicine, survivors should engage in at least 150 minutes of moderate intensity aerobic activity and 2 days of muscle strengthening per week to improve physical function, health-related quality of life, and weight management, among other health benefits. Despite this, 53-83% of cancer survivors do not meet guidelines, and PA is not part of standard cancer care. Therefore, this study aims to determine the effect of PA at diagnosis on mortality in women with breast cancer. METHODS: Participants were recruited from 2004-2017 as part of the ongoing Strength and Range of Motion cohort study. Women were eligible if they had recently been diagnosed with stage 0-IV breast cancer and were scheduled to receive surgery. The primary outcome was defined as all-cause mortality, collected via electronic health record. PA exposure was assessed using the Godin Leisure-Time Exercise Questionnaire (GLTEQ). Participants were asked to report frequency, intensity (mild, moderate, or strenuous), and duration of PA each week during the previous month, and the number of days for each intensity are weighted to produce a total activity score. Data will be analyzed using Cox proportional hazards models to estimate the hazard ratio for the association between PA exposure at diagnosis and all-cause mortality, adjusting for demographic and clinical covariates. ANTICIPATED RESULTS: At diagnosis, women (n=392) were, on average, 57.1±11.9 years old and overweight (M BMI=29.2±6.2 kg/m2) with early-stage breast cancer diagnosis (45.6% Stage I). Across a median follow-up period of 151 months, 73 deaths have been recorded thus far. Participants reported low levels of PA (M GLETQ=15.8±19.6) at time of diagnosis. Once analyses are complete, it is expected that meeting PA guidelines at time of diagnosis will be associated with improved survival in women diagnosed with breast cancer. If findings support the hypothesis, this would provide evidence to support early PA promotion efforts in women with breast cancer.

This document is currently not available here.