Physical Activity Together for Multiple Sclerosis (PAT-MS): A randomized controlled feasibility trial of a dyadic behaviour change intervention.

Background: Many people with advanced multiple sclerosis (MS) and their care-partners do not engage in sufficient physical activity (PA) for health benefits. We developed "Physical Activity Together for MS (PAT-MS)", a 12-week dyadic behavioural intervention, to promote PA among these dyads. Herein, we evaluated the feasibility of PAT-MS before a definitive trial.

Methods: A randomized controlled feasibility trial, with 1:1 allocation into the intervention or wait-list control condition. Predefined progression criteria included rates of , , , and . Changes in self-reported and accelerometer-measured PA were assessed at baseline and post-intervention using mixed-factor ANOVAs. Effects sizes were calculated as Cohen's .

Results: The rate (i.e., 20 participants in 10 months) was not acceptable. However, (80%) was acceptable. No events were reported. There were high levels of with the intervention (content (median = 6 out of 7), facilitator (median = 7 out of 7), and delivery (median = 5 out of 7)) and a (92% of the group sessions, 83% of the individual support calls, and 80% of the practice activities were completed). There were statistically significant time-by-condition interactions on self-reported PA, steps/day, and %wear time and minutes in sedentary behaviour, and moderate-to-vigorous PA from baseline to post-intervention in people with MS and their family care-partners.

Conclusion: PAT-MS appears feasible, safe, and efficacious for PA promotion in MS dyads. We established effect size estimates to power a future definitive trial and identified necessary methodological changes to increase the efficiency of study procedures and improve the quality of the intervention.

Trial Registration: ClinicalTrials.gov NCT04267185; Registered February 12, 2020, https://clinicaltrials.gov/ct2/show/NCT04267185.