Physical activity on prescription in patients with hip or knee osteoarthritis: A randomized controlled trial

Objective: To evaluate whether physical activity on prescription, comprising five sessions, was more effective in increasing physical activity than a one-hour advice session after six months. Design: Randomized, assessor-blinded, controlled trial. Setting: Primary care. Subjects: Patients with clinically verified osteoarthritis of the hip or knee who undertook less than 150 minute/week of moderate physical activity, and were aged 40-74 years. Interventions: The advice group (n = 69) received a one-hour session with individually tailored advice about physical activity. The physical activity on prescription group (n = 72) received individually tailored physical activity recommendations with written prescription, and four follow-ups during six months. Main measures: Patients were assessed at baseline and six months: physical activity (accelerometer, questionnaires); fitness (six-minute walk test, 30-second chair-stand test, maximal step-up test, one-leg rise test); pain after walking (VAS); symptoms (HOOS/KOOS); and health-related quality of life (EQ-5D). Results: One hundred four patients had knee osteoarthritis, 102 were women, and mean age was 60.3 +/- 8.3 years. Pain after walking decreased significantly more in the prescription group, from VAS 31 +/- 22 to 18 +/- 23. There was no other between groups difference. Both groups increased self-reported activity minutes significantly, from 105 (95% CI 75-120) to 165 (95% CI 135-218) minute/week in the prescription group versus 75 (95% CI 75-105) to 150 (95% CI 120-225) in the advice group. Also symptoms and quality of life improved significantly in both groups. Conclusion: Individually tailored physical activity with written prescription and four follow-ups does not materially improve physical activity level more than advice about osteoarthritis and physical activity.