Physical Inactivity as an Early Sign of Frailty in Young Adult Survivors of Childhood Acute Lymphoblastic Leukemia.

Young adult survivors of childhood leukemia have been reported with increased likelihood of age-related comorbidities compared with the general population. We compared the prevalence of frailty in young adult survivors of childhood acute lymphoblastic leukemia (n=58, median age=23 y, median survival time=18 y) with age-matched and sex-matched controls without history of cancer. Frailty phenotypes were determined using Fried frailty model. Association between frailty status and cardiometabolic conditions, systemic inflammation, and T-cell immunophenotype changes were also examined. Frailty and prefrailty were more common among survivors compared with controls (58.6% vs. 34.5%, P=0.019). Physical inactivity (39.7%) was the most frequently observed frailty criterion among the survivors. Prevalence of cardiometabolic conditions was comparable between the robust and frail/prefrail survivors. Robust survivors had a higher level of T-cell activation than the prefrail/frail survivors (P<0.05), but no significant difference was observed for systemic inflammatory markers (IL-6 and C-reactive protein) and percentage of terminally differentiated T cells. Signs of frailty, especially physical inactivity, was detected in childhood acute lymphoblastic leukemia survivors early in their third decade of life. Survivors who were prefrail/frail also had altered T-cell activation; however, the role of such changes in T-cell phenotype in the etiology of frailty warrant further investigation.