Vascular endothelial growth factor (VEGF) in children, adolescents and young adults with Type 1 diabetes mellitus: relation to glycaemic control and microvascular complications

Aims To evaluate serum levels of vascular endothelial growth factor (VEGF) in a large group of children, adolescents and young adults with Type 1 diab etes mellitus to investigate whether increased VEGF concentrations are asso ciated with long-term glycaemic control and microvascular complications. Methods The study involved 196 patients with Type 1 diabetes mellitus (age range 2-24 years, onset of diabetes before the age of 12 years, duration of disease longer than 2 years), without clinical and laboratory signs of mic rovascular complications: they were divided into three groups (group 1 - n = 37, age < 6 years; group 2 - n = 71, age 6-12 years; group 3 - n = 88-age < 12 years). Fifty-three adolescents and young adults (age 16.1-29.7) with different grades of diabetic retinopathy and microalbuminuria were also se lected (group 4). A total of 223 healthy controls were matched fur age and sex with each group of patients with diabetes mellitus. Results VEGF serum levels were significantly increased in pre-school and pr epubertal children with diabetes as well as in pubertal patients compared t o controls. VEGF concentrations were markedly increased in adolescents and young adults with microvascular complications compared with both healthy co ntrols and diabetic patients without retinopathy or nephropathy. Multivaria te analysis showed that elevation of VEGF in serum was an independent corre late of complications. One-year mean HbA(1c) values were significantly corr elated with VEGF concentrations (r = 0.372; P < 0.01). Children with HbA(1c ) levels greater than 10% had significantly higher VEGF concentrations when compared with matched patients whose HbA(1c) levels were lower than 10%. I n poorly controlled diabetic children (HbA(1c) > 10%), long-term (2 years) improvement of glycaemic control (aiming at HbA(1c) < 7%) resulted in a sig nificant reduction of VEGF levels. Conclusions VEGF serum concentrations are increased in prepubertal and pube rtal children with diabetes. Glycaemic control influences VEGF serum levels . Severity of microvascular complications is associated with marked increas e of VEGF concentrations in the serum of these patients.