Chronic Pain, Physical Activity, and All-Cause Mortality in the US Adults: The NHANES 1999-2004 Follow-Up Study

Purpose: The purposes of this study were (1) to examine the relationship between chronic pain and the risk of all-cause mortality and (2) to explore the role of physical activity (PA) in this relationship. Design: Prospective cohort study. Setting: The National Health and Nutrition Examination Survey (NHANES) conducted between 1999 and 2004. Participants: A total of 7384 adults aged ≥40 years old. Measures: Chronic pain and PA were assessed based on the responses to miscellaneous pain and leisure-time PA questionnaires collected during the household interview. The 2011 mortality data from the National Center for Health Statistics were linked to the NHANES participants. Analysis: Cox proportional hazard analyses after accounting for the complex sampling design of the NHANES. Results: After adjusting for several key covariates including sociodemographic variables, chronic health conditions, and unhealthy lifestyle behaviors, individuals with localized or widespread chronic pains showed greater risk of all-cause mortality when compared to individuals with no chronic pain (hazard ratios [HRs] = 1.26 and 1.41, respectively). However, the association was attenuated by further adjustment of PA levels, where engagement of PA ≥150 min/wk was associated with reduced risk of mortality regardless of chronic pain conditions ( P for trends between <.001 and .028). The joint analysis further demonstrated that individuals with localized or widespread chronic pains who had PA ≥150 min/wk had lower risk of mortality (HRs = 0.53 and 0.58, respectively) when compared to those without chronic pain who reported no leisure time PA. Conclusion: This study highlighted the important role of PA in reducing the risk of mortality for individuals with chronic pain. Further public health efforts to promote PA in this vulnerable population group are required.