To estimate the relationship between physical activity and health-related utility for people with knee osteoarthritis (OA) and implications for designing cost-effective interventions.
We used generalized estimating equation regression analysis to estimate partial association of accelerometer-measured physical activity levels with health-related utility after controlling for demographics, health status, knee OA severity level, pain, and functioning.
Moving from the lowest to the middle tertile of physical activity level was associated with a 0.071 (P < 0.01) increase in health-related utility after controlling for demographics and a 0.036 (P < 0.05) increase in utility after controlling for demographics, health status, knee OA severity level, weight, pain, and functional impairments.
Intervention programs that move individuals out of the lowest tertile of physical activity have the potential to be cost effective.