Title: Improving cardiovascular health in patients with end stage renal disease using a structured programme of exercise.
Funder: Department of Health and Social Care

Abstract: Haemodialysis (HD) patients display hugely elevated rates of cardiac mortality, accounting for 43% of all cause deaths in this group. However, this rate of cardiovascular attrition is not driven by the same risk factors, or pathophysiological processes, that are important in the general population. According to the United States Renal Data System database, 64% of all cardiac mortality among HD patients is due to sudden cardiac death (SCD) or arrhythmias, around 100 times higher than the background population, and this is due to factors unique to HD patients. These include abnormalities in myocardial structure and function such as left ventricular hypertrophy (present in at least 75% of dialysis patients), interstitial fibrosis and microvascular disease. To date, efforts to address these factors have concentrated on medical therapies, which have yet to show positive benefits and further research into interventions to reduce SCD in dialysis patients is overdue. In the general population, lifestyle changes that result in increased physical exercise lower mortality. HD patients are less active than even sedentary healthy people withThis study aims to provide answers to unresolved questions regarding aspects of both safety and efficacy of an intradialytic exercise program in reducing the potential risk of cardiovascular disease and SCD in dialysis patients. The study will be a cohort-controlled trial between two out-patient dialysis units comparing the intervention of a structured 6-month intradialytic exercise programme (cycling) with a non-intervention control group. After recruitment, patients will first take part in a familiarisation session, included after consultation with patients, followed by the initial cardiovascular study session. Patients who commence the exercise program will have a run in of 1 month before the required study period of 6 months. Patients will then undergo an identical study session at which point the protocol will be complete. Patients will be offered the choice of continuing within the exercise program if desired. The benefit to patients will be immediate. Locally, this will help to facilitate the introduction of an exercise programme within an additional dialysis unit. This is part of our ongoing commitment to promoting healthy lifestyle in dialysis patients which has been driven by patient demand. Nationally and internationally, it will fill a crucial knowledge gap in the literature that will enable other centres to confidently adopt a safe and effective protocol that can be used by their patients. Ultimately, this will inform further studies into behavioural change to maximise safe patient participation in exercise.

Lay abstract: Haemodialysis patients die primarily of cardiovascular disease, the commonest of which is sudden cardiac death. Haemodialysis patients have a number of additional, non-traditional cardiovascular risk factors unique to their disease condition including muscle wasting, chronic malnutrition and inflammation. Intuitively, exercise has the potential to positively impact upon all of these problems but its incorporation into routine care has been slow as there are very few studies that have assessed the effectiveness, safety or feasibility of exercise programs in this high-risk population. There is widespread agreement that long-term, controlled studies into the safety and benefits of exercise training are desperately needed.

Research activity codes: 6.7 PHYSICAL
Health categories: CARDIOVASCULAR;RENAL AND UROGENITAL