title: Dynamics of blood electrolytes in repeated hyper- and/or hypoglycaemic events in patients with type 1 diabetes.
abstract: OBJECTIVE
  Electrolyte disturbances are well-known consequences of the diabetic pathology. However, less is known about the cumulative effects of repeated changes in glycaemia, a characteristic of diabetes, on the electrolyte balance. We therefore investigated the ionic profiles of patients with type 1 diabetes during consecutive hyper- and/or hypoglycaemic events using the glucose clamp.
  
  
  METHODS
  In protocol 1, two successive hyperglycaemic excursions to 18 mmol/l were induced; in protocol 2, a hypoglycaemic excursion (2.5 mmol/l) was followed by a hyperglycaemic excursion (12 mmol/l) and another hypoglycaemic episode (3.0 mmol/l).
  
  
  RESULTS
  Blood osmolarity increased during hyperglycaemia and was unaffected by hypoglycaemia. Hyperglycaemia induced decreases in plasma Na(+) Cl(-) and Ca(2+) concentrations and increases in K(+) concentrations. These changes were faithfully reproduced during a second hyperglycaemia. Hypoglycaemia provoked rapid and rapidly reversible increases in Na(+), Cl(-) and Ca(2+). In sharp contrast, K(+) levels displayed a rapid and substantial fall from which they did not fully recover even 2 h after the re-establishment of euglycaemia. A second hypoglycaemia caused an additional fall.
  
  
  CONCLUSIONS
  Repeated hyperglycaemia events do not lead to any cumulative effects on blood electrolytes. However, repeated hypoglycaemias are cumulative with respect to K(+) levels due to a very slow recovery following hypoglycaemia. These results suggest that recurring hypoglycaemic events may lead to progressively lower K(+) levels despite rapid re-establishment of euglycaemia. This warrants close monitoring of plasma K(+) levels combined with continuous glucose monitoring particularly in patients under intensive insulin therapy who are subject to repeated hypoglycaemic episodes.
  
  
  BACKGROUND
  Clinicaltrial.gov NCT01060917.
authors.affiliation: Solianis Monitoring AG, Leutschenbachstrasse 46, CH-8050 Zürich, Switzerland. andreas.caduff@solianis.com
authors.forename: A
authors.initials: A
authors.lastname: Caduff
authors.forename: H U
authors.initials: HU
authors.lastname: Lutz
authors.forename: L
authors.initials: L
authors.lastname: Heinemann
authors.forename: G
authors.initials: G
authors.lastname: Di Benedetto
authors.forename: M S
authors.initials: MS
authors.lastname: Talary
authors.forename: S
authors.initials: S
authors.lastname: Theander
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D002118:Calcium / Q000097:blood; D002712:Chlorides / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006943:Hyperglycemia / Q000097:blood*; D007003:Hypoglycemia / Q000097:blood*; D008297:Male; D011188:Potassium / Q000097:blood; D012964:Sodium / Q000097:blood; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D002712:Chlorides; D012964:Sodium; D011188:Potassium; D002118:Calcium