Purpose: The association of recreational physical activity (RPA) with mortality is well established only for breast and colon cancers and few studies have evaluated relationships for exercising before and after diagnosis, across multiple disease sites. We examined the joint associations of pre- and post- diagnosis RPA with mortality in a cohort of 5,807 patients enrolled in the Data Bank and BioRepository at Roswell Park.
Methods: Patients were classified into one of four activity categories (habitually active, increased activity after diagnosis, decreased activity after diagnosis, habitually inactive). Cox proportional hazards models were used to estimate the associations of activity status with mortality.
Results: In comparison to patients who were habitually inactive, habitually active patients experienced a 39% decreased hazard of all-cause mortality (HR = 0.61, 95% CI 0.54-0.69) and a 36% decreased hazard of cancer-specific mortality (HR = 0.64, 95% CI 0.56-0.73). Previously inactive patients who began exercising after diagnosis experienced a 28% decreased hazard of all-cause (HR = 0.72, 95% CI 0.59-0.89) and cancer-specific mortality (HR = 0.72, 95% CI 0.57-0.91) in comparison to patients who remained inactive. Patients engaging in 3-4 sessions/week experienced the greatest survival advantages, but 1-2 sessions/week also yielded significant survival advantages in comparison to inactivity.
Conclusion: Low-to-moderate frequency pre- and post-diagnosis RPA was associated with significantly decreased mortality in patients diagnosed with a variety of malignancies. These observations solidify the clinical and public health importance of the message that some regular activity is better than inactivity, which is particularly encouraging, given that cancer survivors can be overwhelmed by current daily physical activity recommendations.
Keywords: Mortality; Physical activity; Survival.