Growth hormone deficiency and cardiovascular risk factors in childhood cancer survivors

Abstract

6614 Background: Childhood cancer survivors (CCS) have a high frequency of growth hormone deficiency (GHD) and risk of early cardiovascular disease (CVD). This study examined the relations between GHD and risk factors for CVD in CCS. Methods: Anthropometrics, blood pressure, lipids, growth hormone (GH) stimulation test, dual-energy x-ray absorptiometry, abdominal CT, and insulin resistance (IR) (euglycemic, hyperinsulinemic clamp - low M/lbm signifies IR) were obtained in 174 CCS, mean age 15±2 years and 89 healthy sibling controls, mean age 13.5±3 years. Linear regression evaluated the relations between GHD and CVD risk factors, adjusted for sex, age, pubertal stage, and body mass index (BMI) or visceral fat. Results: 62 CCS (36%) had GHD. There were no significant measurement differences between non-GHD CCS and controls. Compared to controls, GHD CCS who never received GH (N = 34) had greater BMI (24.8 vs 20.8 kg/m2, p < 0.0001), percent body fat (36.1% vs 25.8%, p < 0.0001), visceral fat (34.8 vs 19.6 cm2, p < 0.0001), and triglycerides (TG) (120.2 vs 83.8 mg/dL, p = 0.001) and were more IR (M/lbm 11.1 vs 14.2 mg/kg/min, p = 0.0006). Adjustment for BMI and visceral fat did not change the IR or TG results. GHD CCS currently on GH had lower BMI (21.9 kg/m2, p = 0.02), percent body fat (31.2%, p = 0.08), and visceral fat (26.5 cm2, p = 0.03) compared to those not treated. IR and TG were not different between treated and not treated GHD CCS. Conclusions: GHD is a common finding in CCS and is significantly associated with adiposity, IR, and elevated TG.There is a suggestion that GH treatment had a positive impact on adiposity, but not IR and TG levels. These study findings imply that CVD risk factors are present in CCS with GHD independent of body fatness, suggesting that the cancer diagnosis or treatments received may lead to early cardiovascular disease in childhood cancer survivors. No significant financial relationships to disclose.