Objective: To analyze direct medical costs among US adults with arthritis and estimate the proportion associated with inactivity.
Methods: In the 1987 National Medical Expenditure Survey, arthritis was defined using questions on self-reported, doctor-diagnosed arthritis or rheumatism. Physical activity was defined using a self-report question on level of activity. Inactivity-associated medical costs were derived by subtracting costs for active adults from costs for inactive adults after controlling for functional limitation.
Results: Among 5,486 adults with arthritis, inactive persons had higher medical costs than did active persons in all demographic groups examined. In multivariate models adjusting for key covariates, the proportion of costs associated with inactivity averaged 12.4% ($1,250 in 2000 dollars) and ranged from 7.8% to 14.3% among various demographic groups.
Conclusion: Inactivity-associated medical costs among persons with arthritis are considerable. Physical activity interventions may be a cost-effective strategy for reducing the burden of arthritis.