Physical activity and pain in people with and without cancer.

ABSTRACT

BACKGROUND: Performing physical activity may provide analgesic benefit, although this effect is more established for noncancer pain rather than cancer pain. The relationship between physical activity and pain outcomes in adults with and without a history of cancer was examined. METHODS: Totals of 51,439 adults without a cancer history and 10,651 adults with a cancer history from the Cancer Prevention Study II Nutrition Cohort were included. Exposures included self-reported moderate to vigorous physical activity (MVPA) as well as 2-year change in MVPA. Pain outcomes included pain intensity (primary outcome) and analgesic use (secondary outcome). RESULTS: MVPA was inversely associated with pain intensity for adults with (odds ratio [OR], 0.84 [≥15 metabolic equivalent of task (MET) h/week vs. <7.5 MET h/week]; 95% confidence interval [CI], 0.76-0.93) and without (OR, 0.79; 95% CI, 0.75-0.82) a history of cancer. Compared to remaining inactive, participants who became sufficiently active (cancer OR, 0.76; 95% CI, 0.68-0.86; no cancer OR, 0.73; 95% CI, 0.69-0.77), became inactive (cancer OR, 0.79; 95% CI, 0.71-0.88; no cancer OR, 0.84; 95% CI, 0.80-0.89), or remained sufficiently active (cancer OR, 0.66; 95% CI, 0.60-0.72; no cancer OR, 0.62; 95% CI, 0.60-0.65) also reported less pain. Physical activity was not related to analgesic use. CONCLUSIONS: The relationship between physical activity and pain intensity was not substantially different between people with and without a history of cancer. Cancer survivors who perform more activity, or who increase their activity, may experience less pain than cancer survivors who consistently perform less. PLAIN LANGUAGE SUMMARY: People who have had cancer often experience ongoing pain. Being physically active may help reduce the intensity of the pain they experience.