Background: Chronic pain (CP) is an important public health problem because of its high prevalence and its effects on the physical and psychological well-being of individuals. The association between CP and physical activity (PA) has been discussed in previous literature. However, in most studies, the assessments of PA is done via self report, which can be affected by substantial bias and measurement error. In recent years, the use of wearable technology allowed the objective quantification of the frequency, duration, and intensity of PA. The current study is focused on assessing the associations between objectively measured PA chronic upper limb pain, chronic spinal pain, and chronic lower limb pain in U.S. adults.
Methods: The sample was comprised of U.S. adults aged between 25 and 85 years from the 2003-2004 National Health and Nutritional Examination Survey data (NHANES, N = 2, 516), and was stratified into age- and gender-specific groups. PA data obtained via hip-worn accelerometry were summarized into 6 objective measures of volume and 2 measures of fragmentation. Survey-weighted regression models were conducted which regressed each PA measure on location-specific pain indicator, with and without adjustment for potential confounders, including age, race/ethnicity, behaviors, and medical conditions.
Results: Chronic upper limb pain, chronic spinal pain, and chronic lower limb pain showed higher prevalence among females and middle-aged study participants. All three types of CP were strongly associated with lower levels of physical activity in 45-65 years old females. Males aged 25-45 or 65-85 years old with either CP in spine or leg also engaged in less physical activity than those without pain. The statistical significance of the associations remained, even after adjusting for relevant covariates.
Conclusion: This study identified statistically significant associations between objectively measured PA and self-reported CP. The magnitude of the signal varies with the reported location of CP, gender, and age category. These findings may inform that clinical management could be targeted by the CP location. Moreover, results emphasized the importance of wearable technology for providing objective and reproducible measurements in health-related research
