Introduction
Obesity is an increasing problem in the United States, with one in five adolescents obese,1 and a leading cause of morbidity and mortality. The negative consequences of obesity on health has been well documented in the literature,2,3 prompting clinical and public health measures for both treatment and prevention.4 Further, certain individuals, such as survivors of childhood malignant diseases including acute lymphoblastic and myeloid leukemias (ALL and AML) have demonstrated increased risk for obesity5–8 and cardiometabolic disease9–11 in comparison to their corresponding age group in the general population. This increased susceptibility for weight gain has been noted early in treatment, throughout treatment, and well beyond.12
Hematopoietic cell transplantation (HCT) is a well-established and widely utilized treatment for a variety of malignant and non-malignant conditions.13 Efforts to better understand and predict the impacts of comorbidities on transplant outcomes have led to the creation of the HCT comorbidity index, which includes obesity as one of the factors for risk assessment and prediction of nonrelapse mortality and survival.14 With recent studies demonstrating an association between obesity and reduced survival in adult15 and pediatric16 HCT recipients, the growing interest on body habitus, a potentially modifiable risk factor, and its effects on HCT outcomes have prompted research on the converse – the influence of HCT on body mass index (BMI). Thus far, the literature has demonstrated that pediatric HCT recipients may experience a reduction in BMI after transplantation,17 as well as an increase.18 As the data on the weight status of children after HCT is limited and inconsistent, further exploration in this field is needed.
In this study, we sought to characterize the interactions between pediatric BMI and HCT outcomes at our institution. We have included longitudinal data during the pre-transplant period up to 5 years post-transplantation, to investigate the trends in weight status and outcomes throughout the pre-transplant, immediate post-transplant, and long-term post-transplant periods.