Early and progressive insulin resistance in young, non-obese cancer survivors treated with hematopoietic stem cell transplantation

Background: It is unclear whether there is a causative relationship between the development of metabolic syndrome (MS) and increased risk of early cardiovascular morbidity in patients receiving hematopoietic stem cell transplantation (HSCT) during childhood. Early identification of risk factors associated with insulin resistance, MS, and abnormal glucose tolerance during childhood or adolescence in these patients could represent a useful tool for preventing cardiovascular disorders. Procedure: In a single-center, prospective, descriptive, cross-sectional study, we studied 45 survivors of hematological malignancies (age: 13.9±4.8 years) treated with HSCT before the age of 18 years and 90 matched healthy controls. We collected clinical, imaging, and laboratory data including oral glucose tolerance test (OGTT). Results: 7/45 patients (15.6%) showed abnormal glucose tolerance at OGTT, 1/45 (2.2%) was obese, and none fulfilled the criteria for MS. A waist/height ratio >0.5 was associated with patients with abnormal glucose tolerance (85.7% of cases), compared to patients with normal glucose tolerance (42.1%) and controls (23.3%). In patients with abnormal glucose tolerance, use of total body irradiation (TBI) as conditioning regimen was more common, and time elapsed from HSCT was longer. Conclusions: Patients treated with HSCT may develop insulin resistance early after transplantation. They do not show overt obesity, but have redistribution of fat tissue with central fat accumulation. The main factors associated with increased metabolic risk are TBI and time from HSCT. Evaluation of MS and glucose tolerance should be part of hormonal follow-up, which should be routinely proposed to these patients. Pediatr Blood Cancer 2015;62:1650-1655.