Physical function and quality of life in patients with chronic GvHD: a summary of preclinical and clinical studies and a call for exercise intervention trials in patients

Allogeneic hematopoietic stem cell transplant, to reconstitute the hematopoietic and immune status of patients undergoing myeloablative therapy for hematologic disorders, has been of great benefit in minimizing or eradicating disease and extending survival. Patients who undergo allogeneic hematopoietic stem cell transplant (allo-HSCT) are subject to many comorbidities among which the most significant, affecting quality of life (QoL) and survival, are acute GvHD (aGvHD) and chronic GvHD (cGvHD), resulting from donor lymphocytes reacting to and damaging host tissues. Physical activity and exercise have clearly been shown, in both children and adults, to enhance fitness, improve symptomatology and QoL, reduce disease progression and extend survival for many diseases including malignancies. In some cases, vigorous exercise has been shown to be equal to or more effective than pharmacologic therapy. This review addresses how cGvHD affects patients' physical function and physical domain of QoL, and the potential benefits of exercise interventions along with recommendations for relevant research and evaluation targeted at incorporating this strategy as soon as possible after allo-HSCT and ideally, as soon as possible upon diagnosis of the condition leading to allo-HSCT.