Erythropoietin and vascular endothelial growth factor as risk markers for severe hypoglycaemia in type 1 diabetes
Peter Lommer Kristensen1, Ulrik Pedersen-Bjergaard1, Niels Vidiendal Olsen2, Caper Schalkwijk3 & Birger Thorsteinsson1,4
Aims/hypothesis: Circulating erythropoietin (EPO) and vascular endothelial growth factor (VEGF) increase during hypoglycaemia and may represent a protective hormonal counter-regulatory response. We tested the hypothesis that low levels of EPO and VEGF are associated with a higher frequency of severe hypoglycaemia in a cohort of patients with type 1 diabetes.
Methods: Two hundred and nineteen patients with type 1 diabetes (41% females, age 46±13 years (mean±S.D.), duration of diabetes 21±12 years, and HbA1c (8.5±1.1%) were followed in a 1-year observational study. Plasma EPO and serum VEGF levels were measured at baseline with ELISA. Events of severe hypoglycaemia defined by third party assistance were recorded and validated in telephone interviews within 24 h.
Results: Two hundred and thirty-five episodes of severe hypoglycaemia (1.1 episode per patient-year) were reported by 82 patients (37%). At baseline plasma EPO was 8.6 (3.134.3) U/l (median (range)) and serum VEGF was 52.2 (6.6337) pg/ml. Levels of EPO and VEGF were not associated with frequency of severe and mild hypoglycaemia. Levels of EPO were not associated with age, sex, duration of diabetes, body mass index, HbA1c, C-peptide level or hypoglycaemia awareness status. Levels of VEGF were positively associated with age and female sex.
Conclusions/interpretation: Although several studies suggest that VEGF and EPO may affect brain function during hypoglycaemia, this study does not support random VEGF or EPO levels to determine future risk of severe hypoglycaemia in people with type 1 diabetes.