Inflammation and insulin profiles in men assigned to exercise vs. usual care for prostate cancer: results from the active surveillance exercise (ASX) randomized controlled trial

OBJECTIVES: Physical activity is associated with reduced risk of prostate cancer (PCa) progression and death; changes in insulin sensitivity and inflammation are potential mediating mechanisms. This study examined whether exercise after PCa diagnosis affects insulin-related and inflammatory biomarkers. METHODS: The Active Surveillance Exercise (ASX) randomized controlled trial was assigned to men undergoing active surveillance for low-risk, localized PCa to a 16-week exercise intervention (home-based walking program; n = 26) or printed physical activity recommendations (control group; n = 25). Fasting blood samples were collected at baseline and after 16 weeks. Samples were analyzed for markers of insulinemia (insulin, C-peptide, adiponectin), inflammation (C-reactive protein (CRP)), and prostate-specific antigen (PSA). Biomarker changes over time and between arms were analyzed using linear mixed-effects models and intention-to-treat analysis. RESULTS: 22 (85%) intervention and 23 (92%) control participants, mean (SD) age of 63.6 (6.6) years, provided two blood samples. Average baseline biomarker values were within expected ranges. Analyses showed no changes within or differences in changes between intervention and control groups from baseline to 16 weeks for any biomarker (p > 0.05). CONCLUSIONS: We observed no changes in markers of insulinemia, inflammation, or PSA from a 16-week at-home walking intervention vs. control in individuals with low-risk PCa.