Comparison of physical activity among different subsets of patients with knee or hip osteoarthritis and the general population.

To compare the amount of physical activity (PA) among patients with different subsets of knee or hip osteoarthritis (OA) and the general population. Secondary analyses of data of subjects ≥ 50 years from four studies: a study on the effectiveness of an educational program for OA patients in primary care (n = 110), a RCT on the effectiveness of a multidisciplinary self-management program for patients with generalized OA in secondary care (n = 131), a survey among patients who underwent total joint arthroplasty (TJA) for end-stage OA (n = 510), and a survey among the general population in the Netherlands (n = 3374). The Short QUestionnaire to ASssess Health-enhancing physical activity (SQUASH) was used to assess PA in all 4 studies. Differences in PA were analysed by multivariable linear regression analyses, adjusted for age, body mass index and sex. In all groups, at least one-third of total time spent on PA was of at least moderate-intensity. Unadjusted mean duration (hours/week) of at least moderate-intensity PA was 15.3, 12.3, 18.1 and 17.8 for patients in primary, secondary care, post TJA, and the general population, respectively. Adjusted analyses showed that patients post TJA spent 5.6 h [95% CI: 1.5; 9.7] more time on PA of at least moderate-intensity than patients in secondary care. The reported amount of PA of at least moderate-intensity was high in different subsets of OA and the general population. Regarding the amount of PA in patients with different subsets of OA, there was a substantial difference between patients in secondary care and post TJA patients.