The impact of walk advice and exercise strategies on daily physical activity in patients with intermittent claudication - a randomized controlled trial

Abstract

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Research and Development Council for Southern Gothenburg and Bohuslän and the Healthcare Board, Region Västra Götaland, Sweden. The Swedish state under the agreement between the Swedish government and the county councils, the ALF agreement. Introduction Exercise is a first-line treatment in intermittent claudication (IC). However, as the real impact of exercise interventions on daily physical activity (PA) behaviour remains largely undetermined, it is important to include objectively measured PA as an additional endpoint in clinical trials. Purpose The aim of this study was to investigate the impact of unsupervised Nordic pole walk advice (WA) alone or in combination with hospital-based supervised exercise (SEP) or home-based structured exercise (HSEP) with 1year follow up, on daily PA in patients with IC. Methods In this pre-specified analysis from an RCT, a total of 166 patients with IC (mean age 72 (7.4), 41% women) were randomized to three IC-treatment strategies: WA, WA+SEP or WA+HSEP. All patients received Nordic poles and the advice to walk for 30 min, 3 times weekly (WA strategy). Patients allocated to HSEP, and SEP were offered to participate in an additional 6 month exercise program with muscle resistance and aerobic walking exercises. During the following 7-12 months, patients continued with the exercise program at home, with no further feedback. PA was measured through wearable accelerometer recordings for 7-days consecutive periods at baseline, 3, 6, and 12 months. Studied PA outcomes were steps/day, time spent within a stepping cadence ≥100 steps/min, time spent in upright position (standing still and stepping), number of sit to stand transitions, number of sitting bouts of >30 min and >60 min. Intergroup comparisons were performed with one-way analysis of variances ANOVA and intragroup comparisons by paired sample t-test. Results No statistically significant intergroup differences were observed in steps/day over time. HSEP and SEP numerically improved in steps/day at 3 months (HSEP: +472 steps, 95% CI: -146 to 1090; SEP: +241 steps, 95% CI: -282 to 764) but again declined at 6 and 12 months, while WA improved in steps/day at 1year (+89 steps, 95% CI: -568 to 747). At 3 months, a significant improvement were observed in favour of HSEP vs. WA in time spent within a stepping cadence ≥100 steps/min (P=.01) and at 6 months, a significant decrease in favour of SEP vs. WA in number of sitting bouts (>60 min; P=.01). Conclusion Compared to WA alone, receiving additional exercise strategies resulted in a trend toward increased steps/day and time spent within a stepping cadence ≥100 steps/min at 3 months. The opposite pattern occurred at 1year follow-up with a trend for WA to increase in steps/day, while the exercise strategies declined. No firm conclusions can be drawn on the impact of HSEP, SEP and WA strategies on daily PA, and future studies should focus on elaborating on factors that increase daily PA levels in patients with IC. Such studies also need to attach a high priority to develop exercise interventions that translate to more sustainable improvements in daily PA levels in this target population.