Survival benefits of varying physical activity levels in a heterogeneous colorectal cancer cohort: The Disparities and Cancer Epidemiology (DANCE) study

Background: Recreational physical activity has been shown to improve survival among colorectal cancer (CRC) patients. With a growing survivor population, it is necessary to understand whether there are survival benefits across physical activity levels and across sociodemographic and clinical features. Methods: Disparities and Cancer Epidemiology (DANCE) is a population-based cohort of CRC survivors from metro-Detroit and Louisiana. Self-reported moderate and vigorous recreational physical activity was modeled continuously and categorically as none, low (<7.5 MET-hrs/wk), and high (7.5+ MET-hrs/wk). Survival models estimated hazard ratios (HRs) for physical activity with all-cause and CRC-specific survival. Models were stratified by sociodemographic and clinical features; cross-product terms estimated interaction with physical activity. Results: Of 1,107 participants, 26.5% were inactive, 49.1% had low physical activity, and 24.5% had high physical activity. Compared to inactivity, low activity was associated with 44% higher overall survival (HR= 0.56, 95% CI: 0.42, 0.75), and high activity with 66% higher survival (HR=0.34, 95% CI: 0.22, 0.53; P-trend=0.01). Adjustment for comorbidities, quality of life, BMI, and BMI-change did not alter results. Results remained significant for CRC-specific survival (low: HR=0.65, 95% CI: 0.44, 0.96; high: HR=0.45, 95% CI: 0.25, 0.80). Associations were consistent across sociodemographic and clinical features other than BMI and race; survival benefits were larger among White survivors. Conclusion: Any recreational physical activity is associated with longer overall and CRC-specific survival, regardless of sociodemographic or clinical characteristics for the most part. Any physical activity may have survival benefits for CRC survivors, but meeting physical activity guidelines may have the greatest benefit.