Physical Fitness and Frailty in Males after Allogeneic Hematopoietic Stem Cell Transplantation in Childhood: A Long-Term Follow-Up Study

SIMPLE SUMMARY: The prevalence of frailty is increased among young adult childhood cancer survivors and is associated with early morbidity and mortality. The aim of our study was to analyze physical fitness, physical activity and the prevalence of frailty in male long-term survivors of pediatric allogeneic hematopoietic stem cell transplantation. We observed significantly lower muscle strength and muscle endurance in the hand-grip and sit-to-stand tests compared to the age and sex matched normative reference values of the tests. Furthermore, 30% of the survivors were considered pre-frail or frail. Chronic graft-versus-host disease, shorter stature, higher body fat mass and hazardous drinking predicted prefrail/frail status. Common cardiovascular risk factors were associated with poor physical fitness and low physical activity level. These results indicate a need for cardiometabolic follow up as well as health education in the decades following HSCT. ABSTRACT: Purpose and methods: To analyze physical fitness, physical activity and the prevalence of frailty in male long-term survivors of pediatric allogeneic hematopoietic stem cell transplantation (HSCT). We performed a Nordic two-center study of 98 male survivors (mean age 28.7 years, range 18.5–47.0) treated with pediatric allogeneic hematopoietic stem cell transplantation (HSCT) 1980–2010 in denmark or finland. physical fitness was evaluated by the dominant hand grip-strength, timed up-and-go, sit-to-stand, gait speed and two-minute walk tests. Results: Survivors presented significantly lower muscle strength and muscle endurance in the dominant hand-grip strength (median Z-score −0.7, range −4.3–3.9) and sit-to-stand tests (median Z-score −1.5, range −3.5–2.5) compared to age and sex matched normative values of the tests. However, mobility and gait speed were not affected on a group level. The prevalence of frailty (pre-frail 20% or frail 10%) was high among the survivors. In multiple regression analysis, chronic graft-versus-host disease, shorter stature, higher body fat mass and hazardous drinking predicted prefrail/frail status. Common cardiovascular risk factors, such as increased levels of serum triglycerides, higher resting heart rate and diastolic blood pressure, were associated with lower physical fitness. Conclusion: Low muscle strength and a high incidence of frailty were observed in survivors of pediatric HSCT. There is a predominant risk of cardiovascular and metabolic diseases in the long-term.