Background/Purpose: Current guidelines emphasize an active lifestyle in the management of knee osteoarthritis (OA), but up to 90% of OA patients are inactive. Several modifiable risk factors are associated with low physical activity participation, including lack of motivation, doubts about effectiveness of exercise, and lack of health professional advice regarding ways to adjust their activities based on symptoms. Our study aimed to assess the efficacy of a wearable-enabled physical activity counselling program for improving activity participation and disease status in people with knee OA.

Methods: Eligible participants had a self-reported knee OA diagnosis, or symptoms of knee OA based on a validated questionnaire. After baseline assessment and randomization, the Immediate Intervention Group (II) received group education, a Fitbit, and 4 biweekly phone calls by a physiotherapist to counsel activity goals over a 2-month period. The Delayed Intervention (DI) Group received the program 2 months later. Participants were assessed at baseline (T0) and the end of 2, 4 and 6 months (T1, 2, and 3). Outcome measures included: 1) mean moderate/vigorous physical activity (MVPA) time measured with a SenseWear® monitor; 2) mean daily step count; 3) mean sedentary behaviour time; 4) Knee Injury & OA Outcome Score (KOOS). Analysis of covariance (ANCOVA) was used to evaluate the effect of the group type on the outcome measures at T1, 2, and 3, after adjusting for T0. We assessed three planned contrasts of changes: 1) compared T0–T1 between the two groups to determine if II was superior to DI (the control); 2) compared T0–T2 in II against T0–T3 in DI; 3) compared T0–T2 in II against T1–T3 in the DI. The last 2 models assessed whether the two-month delay had an impact on the effect of the intervention.

Results: In 2015–2016, we recruited 61 participants (II: n=30, 73% women; DI: n=31, 90% women). Both groups were similar in age (II: 61.3 (9.4) years; DI: 62.1 (SD 8.5)] and body mass index [II: 29.2 (5.5); DI: 29.2 (4.8)]. Figure 1 summarizes the results. Pre-specified contrast analyses revealed a significant effect whereby the II group improved in the MVPA time at T0–T1 compared to the DI (contrast coefficient: 25.2; 95% CI 5.5, 44.9; p = 0.01). A significant effect was also found in the mean daily steps at T0–T1 (contrast coefficient: 1,519; 95% CI 256.2, 2,782.3; p = 0.02). We found no significant effect in any outcome measures in the other contrast analyses.

Table 1: Results of outcome measures

Conclusion: Our wearable-enabled counselling program improved MVPA time and step counts in people with a diagnosis or symptoms of knee OA. The finding is important since an active lifestyle is recognized as an important component of successful self-management.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/efficacy-of-a-wearable-enabled-physical-activity-counselling-program-for-people-with-knee-osteoarthritis/