Endocrine Abstracts

Introduction: There is strong evidence that adult survivors of childhood cancer have excess premature vascular morbidity and mortality, the pathophysiological mechanism of which remains unresolved.

Methods: We undertook a cross sectional study to assess cardiovascular risk in long-term survivors of brain tumours following cranial irradiation compared with healthy matched controls. The following cardiovascular markers were measured: full lipid profile, fasting glucose and parameters of body composition. Basal anterior pituitary hormone profile and dynamic pituitary tests (ITT or GST) were also undertaken in the patient group.

Results: 36 patients (mean age 30.9±13.9 years) and 36 controls (mean age 31.5±13.4 years) were assessed. Evidence of hypopituitarism was present in 91.2% of patients (severe GHD 64.7%, partial GHD 26.5%, LH/FSH deficiency 17.6%, severe ACTH deficiency 8.8%). No significant difference was found in the TSH (P=0.2) and free T₄ (P=0.4) values between patients and controls. Total and LDL-cholesterol were significantly higher in patients compared with controls (5.3±1.1 mmol/l vs 4.6±1.0 mmol/l, P=0.007 and 3.1±0.8 mmol/l vs 2.7±0.9 mmol/l, P=0.011 respectively). Body composition analysis showed patients had significantly elevated waist circumference (93.9±15.6 cm vs 80.3±10.9 cm, P<0.001), waist-hip ratio (0.88±0.08 vs 0.82±0.08, P<0.001), fat mass (FM) and FM% (24.0±12.2 kg vs 15.7±6.6 kg, P=0.003 and 29.6±9.7% vs 22.1±8.3%, P<0.001), truncal FM and truncal FM% (13.0±6.7 kg vs 8.2±3.7 kg, P=0.004 and 29.4±10.0% vs 21.0±8.1%, P<0.001) and summative (suprailiac, infrascapular, biceps, triceps) skinfold thickness (75.7±32.3 mm vs 42.5±16.4 mm, P<0.001) when compared with controls. No differences were found in the HDL, triglycerides, glucose, BMI and lean body mass between the two comparison groups.

Conclusion: Our results show that cancer survivors following cranial irradiation demonstrate an adverse lipid and body composition profile, which may contribute to the increased cardiovascular risk of these patients. The high prevalence of hypopituitarism in the patient group may explain at least partially the alterations observed in the cardiovascular risk markers.