Cross-sectoral rehabilitation intervention for patients with intermittent claudication versus usual care for patients in non-operative management - The CIPIC Rehab Study: study protocol for a randomised controlled trial

Introduction: Intermittent claudication (IC) caused by peripheral artery disease (PAD) is a common cardiovascular disease. Patients with IC have reduced walking capacity, restricted activity levels and mobility, and reduced health-related quality of life. The disease leads to social isolation, the risk of cardiovascular morbidity, and mortality. Non-operative management of IC requires exercise therapy and studies show that supervised exercise training is more effective than unsupervised training, yet many patients with IC lack motivation for changes in health behaviour. No studies investigating the effects of existing cardiac rehabilitation targeted patients with IC have been published. The aim of this article is to present the rationale and design of the CIPIC Rehab Study, which examines the effect of a cross-sectoral rehabilitation programme versus usual care for patients in non-operative management for IC. Methods and analysis: A randomised clinical trial aims to investigate whether cardiac rehabilitation for patients with IC in non-operative management versus usual care is superior to treatment as usual. The trial will allocate 118 patients, with a 1:1 individual randomisation to either the intervention or control group. The primary outcome is maximal walking distance measured by the standardised treadmill walking test. The secondary outcome is pain-free walking distance measured by the standardised treadmill walking test, healthy diet measured by a fat-fish-fruit-green score, and level of physical activity measured by an activity score within official recommendations. Statistical analyses will be blinded. Several exploratory analyses will be performed. A mixed-method design is used to evaluate qualitative and quantitative findings. A qualitative and a survey-based complementary study will be undertaken to investigate patients' post-discharge experiences. A qualitative post-intervention study will explore experiences of participation in rehabilitation. Discussion: The study is the first to assess the effect of a cardiac rehabilitation programme designed for patients with IC. The study will describe how to monitor and improve rehabilitation programmes for patients with IC in a real-world setting. Mixed-method strategies can allow for both exploration and generalisation in the same study, but the research design is a complex intervention and any effects found cannot be awarded a specific component. Trial Registration: Retrospectively registered in Clinicaltrials.gov identifier: NCT03730623.