Background: Scalable knee osteoarthritis programs are needed to deliver recommended education, exercise, and weight loss interventions.
Objective: To evaluate two 6-month, telehealth-delivered exercise programs, 1 with and 1 without dietary intervention.
Design: 3-group, parallel randomized (5:5:2) trial. (Australian New Zealand Clinical Trials Registry: ACTRN12618000930280).
Setting: Australian private health insurance members.
Participants: 415 persons with symptomatic knee osteoarthritis and a body mass index between 28 and 40 kg/m2 who were aged 45 to 80 years.
Intervention: All groups received access to electronic osteoarthritis information (control). The exercise program comprised 6 physiotherapist consultations via videoconference for exercise, self-management advice, and behavioral counseling, plus exercise equipment and resources. The diet and exercise program included an additional 6 dietitian consultations for a ketogenic very-low-calorie diet (2 formulated meal replacements and a low-carbohydrate meal daily) followed by a transition to healthy eating, as well as nutrition and behavioral resources.
Measurements: Primary outcomes were changes in knee pain (numerical rating scale [NRS] of 0 to 10, higher indicating worse) and physical function (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]; scale, 0 to 68, higher indicating worse) at 6 months (primary time point) and 12 months. Secondary outcomes were weight, physical activity, quality of life, mental health, global change, satisfaction, willingness to have surgery, orthopedic appointments, and knee surgery.
Results: A total of 379 participants (91%) provided 6-month primary outcomes, and 372 (90%) provided 12-month primary outcomes. At 6 months, both programs were superior to control for pain (between-group mean difference in change on NRS: diet and exercise, -1.5 [95% CI, -2.1 to -0.8]; exercise, -0.8 [CI, -1.5 to -0.2]) and function (between-group mean difference in change on WOMAC: diet and exercise, -9.8 [CI, -12.5 to -7.0]; exercise, -7.0 [CI, -9.7 to -4.2]). The diet and exercise program was superior to exercise (pain, -0.6 [CI, -1.1 to -0.2]; function, -2.8 [CI, -4.7 to -0.8]). Findings were similar at 12 months.
Limitation: Participants and clinicians were unblinded.
Conclusion: Telehealth-delivered exercise and diet programs improved pain and function in people with knee osteoarthritis and overweight or obesity. A dietary intervention conferred modest additional pain and function benefits over exercise.
Primary funding source: Medibank, the Medibank Better Health Foundation Research Fund, and a National Health and Medical Research Council Centre of Research Excellence.