[O]ur findings indicate that adoption of regular exercise consistent with national vigorous exercise recommendations in currently sedentary survivors could confer substantial public health benefits in the rapidly growing population of survivors of childhood cancer.
—Lee W. Jones, PhD, and colleagues
In a report from the Childhood Cancer Survivor Study published in the Journal of Clinical Oncology,1 Lee W. Jones, PhD, of Memorial Sloan Kettering Cancer Center, and colleagues found that vigorous exercise reduces the risk of major cardiovascular events in adult survivors of childhood Hodgkin lymphoma.
In the study, 1,187 survivors of childhood Hodgkin lymphoma with a median age of 31.2 years completed a questionnaire evaluating vigorous-intensity exercise behavior, based on the response to the following question: “On how many of the past 7 days did you exercise or do sports for at least 20 minutes that made you sweat or breathe hard (eg, dancing, jogging, basketball, and so on).”
Data on cardiovascular events were collected in follow-up questionnaires. The primary endpoint was incidence of any major (grade 3 to 5) cardiovascular event.
Over a median follow-up of 11.9 years (range, 1.7–14.3 years), a total of 135 cardiovascular events were reported, including 21 cardiovascular-related deaths. Mean vigorous-intensity exercise behavior was 6.1 metabolic equivalent (MET) h/wk-1 ; 36% of survivors reported having participated in no vigorous-intensity exercise behavior.
The cumulative incidence of any cardiovascular event was 12.2% at 10 years for patients reporting 0 MET h/wk-1 vs 5.2% for those reporting ≥ 9 MET h/wk-1. In multivariate analysis adjusting for attained age, age at diagnosis, sex, race, smoking, education, cardiovascular risk factors, baseline grade 3 to 4 (noncardiovascular) chronic conditions, and anthracycline and chest radiation exposures, the incidence of cardiovascular events decreased across increasing MET categories (P = .002 for trend). Compared with survivors reporting 0 MET h/wk-1, the adjusted rate ratio for any cardiovascular event was 0.87 (95% confidence interval [CI] = 0.56–1.34) for 3 to 6, 0.45 (95% CI = 0.26–0.80) for 9 to 12, and 0.47 (95% CI = 0.23–0.95) for 15 to 21 MET h/wk-1.
Meeting the national vigorous-intensity exercise guideline for cancer of ≥ 9 MET h/wk-1 (ie, ≥ 3 sessions of vigorous intensity exercise/wk of ≥ 20 minutes in duration) was associated with a 51% reduction in risk of any cardiovascular event compared with not meeting the guideline (P = .002).
The investigators concluded: “Vigorous exercise was associated with a lower risk of [cardiovascular] events in a dose-dependent manner independent of [cardiovascular] risk profile and treatment in survivors of [Hodgkin lymphoma]…. [O]ur findings indicate that adoption of regular exercise consistent with national vigorous exercise recommendations in currently sedentary survivors could confer substantial public health benefits in the rapidly growing population of survivors of childhood cancer.” ■
Disclosure: The study was supported by the National Cancer Institute grants and American Lebanese Syrian Associated Charities. For full disclosures of the study authors, visit jco.ascopubs.org.
1. Jones LW, Liu Q, Armstrong GT, et al: Exercise and risk of major cardiovascular events in adult survivors of childhood Hodgkin lymphoma: A report from the Childhood Cancer Survivor Study. J Clin Oncol. October 13, 2014 (early release online).