MINDFUL WALKING IN KNEE OSTEOARTHRITIS: A FEASIBILITY RANDOMIZED CONTROLLED TRIAL

ABSTRACT

Purpose: Current walking interventions for people with knee osteoarthritis (OA) focus on either reducing knee joint loading or on increasing physical activity. There is a need for interventions that could address both quality and quantity of walking for people with knee OA. The goal of this randomized controlled trial (clinicaltrials.gov # NCT03064139) was to determine the feasibility of a mindful walking intervention to improve quality and quantity of walking in people with knee OA. Methods: Individuals with symptomatic knee OA were recruited from the community using advertisements. Study criteria are shown in Table 1. [Formula presented] During enrollment, the more symptomatic knee, or a knee selected at random in case of equal symptoms, was designated as the study knee. After the baseline visit, participants were randomized to either a mindful walking group (MWG) or an attention-matched self-management group (SMG). Participants in both groups received 11 intervention sessions delivered over a 6-month period (4 in 1 st month, 2 each in 2nd and 3rd months, 1 each in 4th, 5th, and 6th months). Interventions were delivered via in-person groups (4-10 in each group) and each session was 1.5-3 hours in duration. For MWG, a certified instructor provided training in mindful walking that includes whole-body movement retraining and mindful body-awareness skill building. Biomechanical elements include shorter stride length, higher cadence, greater toe-in, and more aligned posture. Participants were coached to progressively increase their mindful walking activity each week. Mindfulness elements include mindful body-awareness skills to increase sensitivity and awareness of deviations from the taught techniques. The approach is based on “ChiWalking®” so called because the movement approaches are drawn in part from T’ai Chi. For SMG, a researcher delivered a curriculum consisting of education and self-management techniques (e.g., importance of physical activity and exercise, nutrition, weight-management, etc.). This information was also provided to MWG in a condensed form. Gait analyses and physical performance tests were completed at baseline and 6-months. Physical activity was assessed using a commercial wrist-worn activity monitor (Charge 3, Fitbit Inc, San Francisco, CA). Participant-reported outcomes (PROs) were completed at baseline and every 3-months. Participants were remotely followed for an additional 6-months after the end of the intervention. Given the feasibility nature of the study, primary outcomes included recruitment, adherence, retention and number of adverse events. Secondary outcomes included peak external knee adduction moment [KAM], daily step count, Knee injury and osteoarthritis outcome score (KOOS) Pain, Five Facet Mindfulness Questionnaire (FFMQ), Arthritis Self-Efficacy Scale (ASES), 30-second chair stand test (30STS), 40-meter fast paced walk test (40FPW), and Stair Climbing Test (SCT). Analyses were conducted on intention-to-treat basis with all randomized participants included and missing values were not imputed. Results: Participants were recruited between March 2019 and January 2020. During this period, ∼450 individuals completed pre-screening questionnaires (∼41 per month), 66 completed in-person screening visits, 47 were enrolled, and 44 were randomized (Table 2). Interventions for 19 participants were interrupted, delayed for 3-months, and then transitioned to virtual format due to the COVID-19 pandemic. While the original recruitment goal was 62, the trial was halted earlier due to COVID-19. [Formula presented] Attendance is shown in Table 3. On average, MWG group attended 63% of the sessions vs. 70% in the SMG group. Among those who attended at least 1 session, MWG group attended 69% vs. 77% for SMG. Among those who attended at least 3 sessions, MWG group attended 75% vs. 84% for SMG. Post-intervention, 65% (n=15) and 87% (n=20) of MWG completed the in-person visits and PROs, respectively. In SMG, 81% (n=17) completed in-person visits and PROs. At 12-months, 91% (n=21) and 71% (n 15) completed the PROs for MWG and SMG, respectively. [Formula presented] Participant feedback at 6- and 12-months showed that the intervention was acceptable (Table 4). There were no serious adverse events related to the intervention in either group. Within group and between group differences for secondary outcomes are shown in Table 5. [Formula presented] [Formula presented] Conclusions: Our benchmarks were recruitment over 1.5 years, attendance of 75% in MWG group, and retention of 80% of participants at 6-months. While all of these benchmarks were negatively impacted by COVID-19, the recruitment rates over the period studied, adherence in those who attended at least 3 sessions, and retention for some secondary outcomes were acceptable. Participants in both groups found the interventions helpful, enjoyable, and rated it highly. At 12-month follow-up, MWG participants continued to practice mindful walking 1-2 days a week. Between group differences for secondary outcomes were small. Given the feasibility nature of the study, conclusions regarding efficacy cannot be made and larger trial would be needed. Our results show that our methods are appropriate for conducting such a larger trial.