Trial of Intradialytic Cycling as Kidney Exercise Rehabilitation for cardiac Stunning in Hemodialysis (TICKERS_HD)

Most people with kidney failure require hemodialysis treatment three times per week to clear toxins from the blood. Even though hemodialysis helps to remove waste from the body, it can cause low blood flow to vital organs during dialysis which decreases the travel of oxygen and nutrients to the heart and other organs. The low blood flow causes parts of the heart to pump poorly (called "stunning") and is associated with troublesome symptoms that are difficult to treat such as fatigue, cramping and poor cognition. Heart stunning also leads to more heart damage over time and higher rates of heart disease and death. In our previous studies, exercise during hemodialysis decreased the amount of heart stunning that occurred with treatment. In this study, we will look at the effect of cycling during hemodialysis on heart stunning over a longer time and see whether decreases in heart stunning with exercise improve fatigue after dialysis, symptom burden (the number and severity of symptoms) and other outcomes over 3 months. Since the treatment of heart disease and managing symptoms in individuals on dialysis has been identified as a research priority in Canada, we hope to address an important knowledge gap with this study. We will enrol 160 volunteers who are receiving hemodialysis in 7 centres in Canada, the US and Australia. Half will be randomized to receive usual care. The other half will be randomized to receive usual care plus 3 months of cycling 3 times per week during dialysis. We will assess heart function, fatigue after dialysis and symptom burden between groups over time. The information provided by this study will help us better treat people on dialysis and improve their well-being. Results will also help us plan and design a future study looking at the effect of exercise on longer term outcomes such as cardiac disease and death. Improvements in such outcomes are important for individual health and could also reduce burden and costs to the health care system.