Watch us move: Towards optimal physical functioning in pediatric oncology: determinants and monitoring

Abstract

Despite improved survival rates, children with cancer often experience adverse effects affecting their physical functioning during treatment. They are also vulnerable to low levels of physical activity and poor nutritional status. However, knowledge regarding the incidence of physical impairments, associated risk factors and effective strategies to optimize physical functioning remains limited. The overall aim of this thesis was therefore to investigate physical functioning in children with cancer during specific treatments, identify determinants for physical decline and explore methods to monitor and optimize physical functioning. Research in children with acute lymphoblastic leukemia (ALL) showed that a substantial proportion experienced temporary walking inability around the time of diagnosis and during early treatment. Younger age, weight loss and longer hospitalizations were identified as important risk factors, although all children eventually regained independent walking ability. In pediatric patients undergoing hematopoietic stem cell transplantation (HSCT), physical performance was impaired 100 days after the transplantation. Better pre-transplant physical performance was positively associated with post-transplant outcomes, highlighting the potential value of prehabilitation interventions. To improve insight into physical activity during treatment, the feasibility and validity of smartwatches for long-term monitoring were examined. While smartwatch-based heart rate measurements showed promising validity, step count was underestimated. Long-term feasibility depended strongly on the child’s physical condition, motivation, perceived value and user experience, emphasizing the importance of a personalized monitoring approach. Finally, a literature review revealed a lack of evidence on the effects of protein supplementation on anthropometrics, body composition and physical fitness in children with cancer. Limited evidence from chronically and critically ill pediatric populations suggests potential benefits, but high-quality studies in children with cancer are urgently needed. This thesis provides important insights into the early identification and support of physical problems in children with cancer. As physical decline has a major impact on functional independence and daily life, these findings may ultimately contribute to an improved quality of life for children with cancer.