Stepped Exercise Program for Patients With Knee Osteoarthritis : A Randomized Controlled Trial

Abstract

Background: Evidence-based models are needed to deliver exercise-related services for knee osteoarthritis efficiently and according to patient needs.

Objective: To examine a stepped exercise program for patients with knee osteoarthritis (STEP-KOA).

Design: Randomized controlled trial. (ClinicalTrials.gov: NCT02653768).

Setting: 2 U.S. Department of Veterans Affairs sites.

Participants: 345 patients (mean age, 60 years; 15% female; 67% people of color) with symptomatic knee osteoarthritis.

Intervention: Participants were randomly assigned in a 2:1 ratio to STEP-KOA or an arthritis education (AE) control group, respectively. The STEP-KOA intervention began with 3 months of an internet-based exercise program (step 1). Participants who did not meet response criteria for improvement in pain and function after step 1 progressed to step 2, which involved 3 months of biweekly physical activity coaching calls. Participants who did not meet response criteria after step 2 went on to in-person physical therapy visits (step 3). The AE group received educational materials via mail every 2 weeks.

Measurements: Primary outcome was Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. Scores for the STEP-KOA and AE groups at 9 months were compared by using linear mixed models.

Results: In the STEP-KOA group, 65% of participants (150 of 230) progressed to step 2 and 35% (81 of 230) to step 3. The estimated baseline WOMAC score for the full sample was 47.5 (95% CI, 45.7 to 49.2). At 9-month follow-up, the estimated mean WOMAC score was 6.8 points (CI, -10.5 to -3.2 points) lower in the STEP-KOA than the AE group, indicating greater improvement.

Limitation: Participants were mostly male veterans, and follow-up was limited.

Conclusion: Veterans in STEP-KOA reported modest improvements in knee osteoarthritis symptoms compared with the control group. The STEP-KOA strategy may be efficient for delivering exercise therapies for knee osteoarthritis.

Primary funding source: Department of Veterans Affairs, Health Services Research and Development Service.

Figure 1:

CONSORT Diagram Note: Some participants could not be contacted at one time point but did not withdraw and were successfully contacted at a later time point. Therefore, the follow-up numbers at 6 and 9 months include some people who were not included at the prior time point.

Figure 2:

Numbers of Participants Meeting Criteria for Clinically Relevant Response by Time Point in STEP-KOA Group

Figure 3:

WOMAC Total Score By Study Group and Time Point