Exercise and Risk of Major Cardiovascular Events in Adult Survivors of Childhood Hodgkin Lymphoma: A Report From the Childhood Cancer Survivor Study

PURPOSE: Survivors of Hodgkin lymphoma (HL) are at increased risk of treatment-related cardiovascular (CV) events; whether exercise modifies this risk is unknown. METHODS: Survivors of HL (n = 1,187; median age, 31.2 years) completed a questionnaire evaluating vigorous-intensity exercise behavior. CV events were collected in follow-up questionnaires and graded according to Common Terminology Criteria for Adverse Events (version 4.03). The primary end point was incidence of any major (grade 3 to 5) CV event. Poisson regression analyses were used to estimate the association between exercise exposure (metabolic equivalent MET hours/week(-1)) and risk of major CV events after adjustment for clinical covariates and cancer treatment. RESULTS: Median follow-up was 11.9 years (range, 1.7 to 14.3 years). Cumulative incidence of any CV event was 12.2% at 10 years for survivors reporting 0 MET hours/week(-1) compared with 5.2% for those reporting ≥ 9 MET hours/week(-1). In multivariable analyses, the incidence of any CV event decreased across increasing MET categories (Ptrend = .002). Compared with survivors reporting 0 MET hours/week(-1), the adjusted rate ratio for any CV event was 0.87 (95% CI, 0.56 to 1.34) for 3 to 6 MET hours/week(-1), 0.45 (95% CI, 0.26 to 0.80) for 9 to 12 MET hours/week(-1), and 0.47 (95% CI, 0.23 to 0.95) for 15 to 21 MET hours/week(-1). Adherence to national vigorous intensity exercise guidelines (ie, ≥ 9 MET hours/week(-1)) was associated with a 51% reduction in the risk of any CV event in comparison with not meeting the guidelines (P = .002). CONCLUSION: Vigorous exercise was associated with a lower risk of CV events in a dose-dependent manner independent of CV risk profile and treatment in survivors of HL.