Regular vigorous exercise and increased exercise over 8 years significantly improved mortality risk among adult survivors of childhood cancer, according to a study published in JAMA Oncology.
Adult survivors of childhood cancers have a higher risk of mortality and have a life expectancy that is generally 10 years less than the general population. Regular, vigorous exercise has been associated with improved cardiovascular health and reduced mortality, but whether or not it modifies risk in cancer survivors has not been clarified.
For this retrospective cohort analysis, researchers evaluated the outcomes of 15,450 adult cancer survivors with a cancer diagnosis before age 21. Eligible participants survived 5 years beyond their initial diagnosis, and were older than 18 at the time of baseline enrollment. Vigorous exercise was measured using the Youth Risk Behavior Surveillance Survey, which measured their weekly metabolic equivalent tasks (METs). The average age of study patients was 25.9 years, and the median follow-up was 9.6 years.
After 15 years, results showed that the cumulative incidence of all-cause mortality improved with increasing exercise. For patients who exercised 0 MET-hours/week, 3-6 MET-h/week, 9-12 MET-h/week, and 15-21 MET-h/week, the cumulative incidence of all-cause mortality was 11.7%, 8.6%, 7.4%, and 8.0%, respectively (P<.001).
After adjusting for chronic health conditions and treatment exposures, researchers observed a significant inverse relationship across different measures of exercise and all-cause mortality (P=.02). A further analysis of a subset of 5689 survivors revealed that increased exercise measured over 8 years was associated with a significant 40% reduction in all-cause mortality (P =.001).
The authors concluded that “these findings may be of importance for the large and rapidly growing global population of adult survivors of childhood cancer at substantially higher risk of mortality due to multiple competing risks.”
Scott JM, Li N, Liu Q, et al. Association of exercise with mortality in adult survivors of childhood cancer[published online June 3, 2018]. JAMA Oncol. doi: 10.1001/jamaoncol.2018.2254