title: Erythropoietin during hypoglycaemia in type 1 diabetes: relation to basal renin-angiotensin system activity and cognitive function.
abstract: OBJECTIVE
  Preservation of cognitive function during hypoglycaemic episodes is crucial for patients with insulin-treated diabetes to avoid severe hypoglycaemic events. Erythropoietin has neuroprotective potential. However, the role of erythropoietin during hypoglycaemia is unclear. The aim of the study was to explore plasma erythropoietin response to hypoglycaemia and the relationship to basal renin-angiotensin system (RAS) activity and cognitive function.
  
  
  METHODS
  We performed a single-blinded, controlled, cross-over study with induced hypoglycaemia or maintained glycaemic level. Nine patients with type 1 diabetes with high and nine with low activity in RAS were studied. Hypoglycaemia was induced using a standardized insulin-infusion.
  
  
  RESULTS
  Overall, erythropoietin concentrations increased during hypoglycaemia. In the high RAS group erythropoietin rose 29% (p=0.032) whereas no significant response was observed in the low RAS group (7% increment; p=0.43). Independently, both hypoglycaemia and high RAS activity were associated with higher levels of erythropoietin (p=0.02 and 0.04, respectively). Low plasma erythropoietin at baseline was associated with poorer cognitive performance during hypoglycaemia.
  
  
  CONCLUSIONS
  Hypoglycaemia triggers a rise in plasma erythropoietin in patients with type 1 diabetes. The response is influenced by basal RAS activity. Erythropoietin may carry a neuroprotective potential during hypoglycaemia.
authors.affiliation: Endocrinology Section, Department of Cardiology and Endocrinology, Hillerød Hospital, Dyrehavevej 29, DK-3400, Hillerød, Denmark. pelk@hih.regionh.dk
authors.forename: Peter Lommer
authors.initials: PL
authors.lastname: Kristensen
authors.forename: Thomas
authors.initials: T
authors.lastname: Høi-Hansen
authors.forename: Niels Vidiendal
authors.initials: NV
authors.lastname: Olsen
authors.forename: Ulrik
authors.initials: U
authors.lastname: Pedersen-Bjergaard
authors.forename: Birger
authors.initials: B
authors.lastname: Thorsteinsson
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000097:blood; D003071:Cognition / Q000502:physiology*; D003404:Creatinine / Q000097:blood; D018592:Cross-Over Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000503:physiopathology / Q000523:psychology; D004921:Erythropoietin / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007003:Hypoglycemia / Q000097:blood* / Q000523:psychology; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D012084:Renin-Angiotensin System / Q000502:physiology*; D016037:Single-Blind Method
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D003404:Creatinine; D004921:Erythropoietin; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin