Tailored Exercise Helps Knee Osteoarthritis, Even With Comorbidity

Tailored exercise therapy has been found to be a safe and efficacious strategy to improve physical functioning for patients who have knee osteoarthritis and a severe comorbidity.

Led by Mariette de Rooij, PhD, of Amsterdam Rehabilitation Research Centre in the Netherlands, a study team hypothesized that patients who have a severe comorbidity could exercise safely if certain adaptations were made in their exercise program.

“The beneficial results of the present study can be attributed not only to the high volume and frequency of the exercise, but also to the several adjustments to the exercise program,” wrote de Rooij and colleagues.

Exercise therapy is included in international guidelines as a recommendation for managing knee osteoarthritis. Specifically, exercise therapy helps reduce joint pain and improve physical functioning. But despite the benefits of exercise for patients with knee osteoarthritis, comorbidities often make it difficult for patients to exercise, which in turn lowers adherence.

Current guidelines do not provide guidance on how to implement exercise therapy for patients with knee osteoarthritis who also have a severe comorbidity. Consequently, both patients and clinicians may seek to reduce exercise as a way to avoid additional pain and aggravation of symptoms.

This, the first known study to evaluate exercise therapy tailored to comorbidity in this patient population, was published online April 24 in Arthritis Care & Research.

The study

This was a single-blind, randomized, controlled trial with 126 patients. Participants were recruited and identified by referral from healthcare providers and advertisements in local newspapers.

Inclusion criteria were a diagnosis of knee osteoarthritis according to the clinical criteria of the American College of Rheumatology and the presence of at least 1 of several target comorbidities-coronary disease, heart failure, type 2 diabetes mellitus, chronic obstructive pulmonary disease, and obesity-all with a diagnosis from a medical specialist. Participants also had to have a severity score of ≥ 2 for comorbidity on the Cumulative Illness Rating Scale.

Patients were randomized to the intervention or control group. The intervention group received exercise therapy, a 20-week individualized, or “tailored,” knee osteoarthritis exercise program that included 2 sessions of 30 to 60 minutes per week under the supervision of a physical therapist. The control group received the current standard of care and were placed on a waiting list for exercise therapy.

The primary outcomes were 2-fold: (1) physical functioning as assessed by the Western Ontario and McMaster Universities Osteoarthritis Index’s subscale physical functioning (WOMAC-pf, Dutch translation) and (2) the 6-minute walk test (6MWT). 

Most participants in the intervention group (86%) received at least two-thirds of the exercise sessions (27 of 40 sessions).

Significant differences between the intervention and control group were found for the WOMAC-pf (B= -7.43 [95% CI: -9.99, -4.87], P<0.001 and the 6MWT (B=34.16 [95% CI: 17.68, 50.64], P<0.001), favoring the intervention group. No serious adverse effects resulted from participation in the exercise therapy program.

“The results should encourage clinicians to consider exercise therapy as a treatment option for patients with knee OA, even in the presence of comorbidity,” the study team concluded.

Disclosures:

This research was supported by the Royal Dutch Society for Physical Therapy and Merck Sharp & Dohme.

Dr. Haverkamp has received grants from Mathys, Implantcast, Arthrex, and Carbylan (less than $10,000 each) and has received grants and/or honoraria from Citera and Imove (less than $10,000 each). Dr. Dekker has received a grant from Merck Sharp & Dohme (less than $10,000).

References:

de Rooij M, van der Leeden M, Cheung J, et al. “Efficacy of Tailored Exercise Therapy on Physical Functioning in Patients With Knee Osteoarthritis and Comorbidity: A Randomized Controlled Trial.” Arthritis Care Res (Hoboken). 2017;69:807-816. doi: 10.1002/acr.23013. Epub 2017 Apr 24.