The HIMALAYAS Trial and Lifestyle Changes in Pediatric, Adolescent and Young Adult Cancer Survivors Study: A Multicentre Randomized Controlled Trial

Pediatric, adolescent and young adult cancer survivors (PAYA-CS) are at higher risk of cardiovascular (CV) morbidity and mortality. This is a consequence of prior cancer-related therapies that have the potential of producing cardiac dysfunction, reducing cardiorespiratory fitness (reduced VO2peak) and psychosocial morbidities (i.e., anxiety and depression). A reduction of physical activity levels can evoke functional limitations resulting in a vicious cycle of reduced exercise tolerance and physical deterioration. To date, there is limited evidence on the use of non-pharmacological strategies such as Cardio-Oncology Rehabilitation (CORE) including structured exercise, behavioural support and risk factor management to improve the outcomes of this underserved population. The HIMALAYAS study is a randomized controlled trial designed to evaluate the impact of a CORE intervention (consisting of six-months home and onsite-based structured moderate to high-intensity aerobic exercise training and CVD risk factor management) on CV and psychosocial health, and the cardiovascular disease risk in PAYA-CS with mild heart dysfunction (stage B heart failure) compared to standard of care (i.e. providing guidance on the current exercise recommendations for cancer survivors). The primary objective of the HIMALAYAS study is to determine whether a six-month supervised CORE intervention, consisting of individualized moderate to high-intensity aerobic exercise training, CVD risk factor modification and enhanced online behavioral support, improves cardiorespiratory fitness (VO2peak; primary outcome), cardiac function, CVD risk factors and biomarkers, and patient-reported outcomes (PROs) at six- months follow-up compared to standard of care (CON) in PAYA-CS with stage B heart failure. The secondary objective is to assess the same outcomes at 12- and 24-months follow-up. We will recruit 336 patients across 5 sites in Canada and upto 134 patients at UHN in 3 years and conclude in 6 years.