Background: Obesity is prevalent in childhood cancer survivors and interacts with cancer treatments to potentiate risk for cardiovascular (CV) death. We tested a remote weight-loss intervention that was effective among adults with CV risk factors in a cohort of adult survivors of childhood acute lymphoblastic leukemia (ALL) with overweight/obesity.
Methods: In this phase 3 efficacy trial, survivors of ALL enrolled in the Childhood Cancer Survivor Study with body mass index (BMI)≥25 kg/m2 were randomized to a remotely-delivered weight-loss intervention versus self-directed weight loss, stratified by history of cranial radiotherapy (CRT). The primary endpoint was the difference in weight loss at 24-months in an intent-to-treat analysis. Analyses were performed using linear mixed effects models.
Results: Among 358 survivors (59% female, median attained age: 37 years, IQR: 33-43), baseline mean (SD) weight was 98.6 kg (24.0) for the intervention group (n=181) and 94.9 kg (20.3) for controls (n=177). Adherence to the intervention was poor; 15% of individuals in the intervention completed 24/30 planned coaching calls. Weight at 24-months was available for 274 (77%) participants. After controlling for CRT, sex, race/ethnicity, and age, the mean (SE) change in weight from baseline to 24-months was -0.4 kg (0.8) for intervention and 0.2 kg (0.6) for control participants (p=0.59).
Conclusions: A remote weight-loss intervention that was successful among adults with CV conditions did not result in significant weight loss among adult survivors of childhood ALL.
Impact: Future interventions in this population must be tailored to the unique needs of survivors to encourage engagement and adherence.