Exercise Adherence Improving Long-Term Patient Outcome in Patients With Osteoarthritis of the Hip and/or Knee

Objective. To determine the effect of patient exercise adherence within the prescribed physical therapy treatment period and after physical therapy discharge on patient outcomes of pain, physical function, and patient self-perceived effect in individuals with osteoarthritis (OA) of the hip and/or knee. Methods. We performed a prospective observational followup study in which 150 patients with OA of the hip and/or knee receiving exercise therapy were followed for 60 months. Data were obtained from a randomized controlled trial, with assessments at baseline and 3, 15, and 60 months of followup. The association between exercise adherence and patient outcomes of pain, physical function, and self-perceived effect was examined using generalized estimating equations analyses. Results. Adherence to recommended home exercises and being more physically active were significantly associated with better treatment outcomes of pain, self-reported physical function, physical performance, and self-perceived effect. The association between adherence and outcome was consistent over time. Adherence to home activities was only associated with better self-perceived effect. Conclusion. Better adherence to recommended home exercises as well as being more physically active improves the long-term effectiveness of exercise therapy in patients with OA of the hip and/or knee. Both within and after the treatment period, better adherence is associated with better patient outcomes of pain, physical function, and self-perceived effect. Since exercise adherence declines over time, future research should focus on how exercise behavior can be stimulated and maintained in the long term.