Physical activity and risk of cancer mortality in patients with and without cancer: is there a dose-response...

The purpose of this study was to examine a dose-response association between aerobic physical activity (APA) and muscle-strengthening exercise (MSE) and their combinations with cancer mortality.

The final 575,439 participants involved in this study were derived from 1997 to 2018 longitudinal follow-up data collected in the National Health Interview Survey (NHIS). The APA and MSE were requested via self-reported questionnaires. These records are linked to the National Death Index and classified as cancer deaths based on the International Classification of Diseases (ICD-10). Statistical analysis was performed by Wilcoxon rank-sum test, chi-square test, and the Cox proportional hazards models.

After adjusting for all covariates, the results demonstrated that the cancer mortality risk for cancer survivors decreased by 23.2%, 35.8%, 42.5%, and 46.7% for those engaging in 0-7.4 MET hours/week, 7.5-14.9 MET hours/week, 15-29.9 MET hours/week, and 30 + MET hours/week, respectively. For non-cancer patients, the cancer mortality risk decreased by 6.9%, 11.9%, 15.1%, and 16.7%. Furthermore, the results showed that the cancer mortality risk for cancer survivors decreased by 34.9%, 30.2%, 32.3%, and 10% for those engaging in 2-3 times/week, 4-5 times/week, 6-7 times/week, and 8 + times/week. For non-cancer patients, the cancer mortality risk decreased by 17.4%, 23.7%, 9.5%, and 10.6%. Among non-cancer patients with insufficient MSE, there was no significant negative correlation between APA and cancer mortality.

The optimal dose response in reducing the risk of cancer mortality may occur at higher levels of APA with MSE 4-5 times/week and 2-3 times/week for primary and secondary prevention. In addition, primary prevention derives a greater advantage from MSE, and a protocol of APA should be emphasized in secondary prevention.