Physical Activity Disparities Contribute To Inequitable Health-related Quality Of Life Among Black Individuals With Knee Osteoarthritis

Knee osteoarthritis (KOA) is the most common form of arthritis, which is a leading cause of disability. While there is no cure for KOA, physical activity has been shown to slow down progress and reduce symptoms, which can improve an individual’s health-related quality of life (HR-QOL). However, racial disparities exist for participating in physical activity (PA), which can result in Black individuals with knee osteoarthritis experiencing lower HR-QOL compared with their white counterparts. PURPOSE. The purpose of this study was to understand disparities of PA, and related determinants, specifically pain and depression, and how these constructs explain why Black individuals with knee osteoarthritis experience lower HR-QOL. METHODS. Data was analyzed from the Osteoarthritis Initiative, which is an NIH funded longitudinal multi-center observational study that collected data from individuals with KOA. The present study analyzed change scores (across 24 months) in pain (WOMAC scale), depression (CES scale), physical activity (PASE), and HR-QOL (SF-12) which was found to be complete among 1658 participants. RESULTS. A MANCOVA model at baseline found Black race to be predictor of high pain, depression, and lower physical activity and HR-QOL, F (4, 2299) = 59.21, p < .001. The findings supported the prospective multi-mediation model which found race to predict pain (β = .39, p < .001), pain to predict depression (β = .13, p < .001), depression to predict physical activity (β = -.10, p < .001), and physical activity to predict quality of life (β = .00, p < .001). The entire indirect pathway was found to be significant (β = -0.18, 95% CI [−0.268, -0.1001]), while direct pathway was no longer significant (β = 0.11, 95% CI [−0.005, 0.222]), denoting total mediation effect. CONCLUSION. The study highlights disparities experienced among Black patients with KOA (higher pain, depression, and lower PA) and explains why they experience lower HR-QOL compared with their white counterparts. Future effective and equitable interventions should address higher levels of pain concerns and depression among Black patients, which would alleviate burden for PA. The program would also need to include additional inequitable barriers of PA experienced among Black individuals such as safety, access, and cost, as identified in the literature.