Home-Based Exercise Program Can Improve Walkability in Peripheral Artery Disease

Results of the MOSAIC trial demonstrate participation in a home-based walking exercise program can lead to improvements in walking ability among adult patients with peripheral artery disease.

A multicenter randomized clinical trial, results of the study, which included 190 adult patients from the United Kingdom, indicate participation in a home-based walking program was associated with a 16.5-meter adjusted difference in 6-minute walking distance after 3 months compared to usual care, but investigators pointed out this failed to exceed the threshold for a large clinically important difference in patients with peripheral artery disease (PAD).

“Results of prior randomized clinical trials of home-based exercise therapy for people with PAD have been mixed, with multiple prior clinical trials showing benefits of home-based exercise for PAD but at least 2 showing no effect of a home-based exercise intervention for PAD,” wrote investigators. “The difference in 6-minute walking distance following this intervention was greater than a small minimal clinically important difference for people with PAD but did not meet the threshold for a large minimal clinically important difference in people with PAD.”

A multicenter randomized clinical trial launched with the intent of evaluating whether a home-based, walking exercise behavior change intervention delivered by physical therapists improved walking capacity, the Motivating Structured Walking Activity in People With Intermittent Claudication (MOSAIC) trial was conducted between January 2018 through September 2020 and randomized 190 patients in a 1:1 ratio to a walking intervention or usual care. The 190 patients randomized in the trial had a mean age of 68 years, 30% were women, 795 were White, and 148 completed the 3-month follow-up.

For inclusion in the study, patients needed to be at least 50 years of age or older, have a diagnosis of PAD determined by the consulting clinical, and have self-reported claudication identified using the San Diego Claudication Questionnaire. Patients were excluded if they had unstable PAD, walking more than 90 minutes per week, having contraindications to exercise determined by the consulting clinician, and completion of any prescribed supervised exercise in the previous 6 months or planned participation in prescribed supervised exercise in the next 6 months.

The primary outcome of interest for the study was 6-minute walking distance at the 3-month follow-up, with8-20 meters serving as the threshold for minimal clinically important difference. The trial also included 8 secondary outcomes of interest.

At the end of the trial, the 6-minute walking distance changed from 352.9 meters at baseline to 380.6 meters at 3 months in the intervention group and from 369.8 to 372.1 meters in the usual care group (adjusted mean between-group difference, 16.7 [95% CI, 4.2 to 29.2]; P=.009).Of the 8 secondary outcomes, only 3 achieved statistical significance. From baseline to 6 months, WELCH scores changed from 18.0 to 27.8 in the intervention group and from 20.7 to 20.7 in the usual care group (adjusted mean between-group difference, 7.4 [95% CI, 2.5 to 12.3]; P=.003), scores on the Brief Illness Perceptions Questionnaire changed from 45.7 to 38.9 in the intervention group and from 44.0 to 45.8 in the usual care group (adjusted mean between-group difference, −6.6 [95% CI, −9.9 to −3.4]; P <.001), and scores on the attitude component of the Theory of Planned Behavior Questionnaire changed from 14.7 to 15.4 in the intervention group and from 14.6 to 13.9 in the usual care group (adjusted mean between-group difference, 1.4 [95% CI, 0.3 to 2.5]; P=.02).

In a related editorial penned by Mary McDermott, MD, a professor of medicine in General Internal Medicine and Geriatrics at Northwestern Medicine, detailed the importance of supervised exercise in the treatment algorithm for patients with PAD and provided perspective into the potential impact of an effective, home-based program to improve walkability.

“A highly effective home-based exercise program has the potential to help millions of people with PAD, including those in rural areas without access to supervised exercise therapy and those unable to travel regularly to the facility to participate,” McDermott wrote. “By avoiding the need for an exercise facility or a coach during each exercise session, home-based exercise programs are likely to be less costly than supervised exercise. Given the absence of alternative highly effective noninvasive therapies for PAD, developing home-based exercise into first-line therapy for PAD is an imperative.”

This study, “Effect of a Home-Based, Walking Exercise Behavior Change Intervention vs Usual Care on Walking in Adults With Peripheral Artery Disease,” was published in JAMA.