Inter-individual responses to a hybrid walking program in patients with peripheral arterial disease - an exploratory analysis of the PROSECO study

Background/Introduction Walking programs are recommended to enhance walking capacity and alleviate symptoms in peripheral arterial disease (PAD). However, not every individual experiences the same benefits following walking therapy. Therefore, early identification of good and poor responders is essential for better personalizing treatments, optimizing resource allocation and improving patient outcomes. Purpose To compare inter-individual variation in patient and clinical characteristics associated with clinically meaningful improvement in a 6-minute walk test following a walking intervention. Methods This is an exploratory analysis of the PROSECO-study including 41 patients with PAD [32 men, mean age=70.3±9.2 yrs, ankle-brachial index=0.66±0.26]who completed a 12 week progressive hybrid walking program. The intervention included one in-hospital supervised exercise session and two home-based walking sessions per week, aiming for 150 minutes of walking at moderate pain intensity. Patient and clinical characteristics, including cardiac autonomic function via heart rate variability, pain free walking distance (PFWD) and maximal walking distance (MWD) by means of a progressive treadmill test and functional capacity by means of a 6-minute walk test (6MWT), were assessed at baseline and following completion of the intervention. Based on an established minimally clinically relevant change in 6MWD, patients were divided into two groups: poor responders (∆6MWT<24 m) and good responders (∆6MWT≥24 m). Results Twenty three patients (56%) were identified as poor responders (median age 75 years, 73.9% male), while 18 patients (44%) were classified as good responders (median age 67.5 years, 83.3% male). 6MWD remained unchanged in the poor responders (median 6MWD pre 391 meters vs. post 389.50 m) and increased in the good responders (median 6MWD pre 478 vs post 501 m (Figure 1D). As shown in Table 1, good responders were younger and presented with a better PFWD at baseline. Good responders showed also a better improvement in PFWD (m), MWD (m) (Figure 1C-D-E) and an improvement in autonomic function (Figure 1A-B). Conclusions Our findings suggest that a significant proportion of patients do not show a significant improvement in functional capacity after walking therapy only. Further investigation is needed to better characterize patients that are more likely to respond favorably to walking therapy thereby enhancing personalisation of effective PAD treatment.