title: Relationship between glycosylated haemoglobin and mean plasma glucose concentration in cystic fibrosis.
abstract: BACKGROUND
  HbA(1c) is recommended for monitoring glycaemic control in people with cystic fibrosis-related diabetes (CFRD). However the relationship between HbA(1c) and mean plasma glucose concentration (MPG) has not been established in CFRD, as in other forms of diabetes mellitus.
  
  
  METHODS
  20 people (13 male, 29.7+/-8.8 years, 10 CFRD) with cystic fibrosis (CF) underwent HbA(1c) measurement and 48 h continuous glucose monitoring for estimation of MPG. The relationship between HbA(1c) and MPG was established and compared to the reported relationship for type 1 diabetes.
  
  
  RESULTS
  HbA(1c) was strongly correlated with MPG (R(2)=0.888, p<0.0001) in CF. The relationship of MPG to HbA(1c) was described by the equation MPG=(1.47xHbA(1c))-1.15, giving a 1.47 mmol L(-1) change in MPG per 1% change in HbA(1c). This equation predicts that MPG in people with CF and HbA(1c) <7.0% will be similar to MPG in people with type 1 diabetes who achieve the same HbA(1c) target.
  
  
  CONCLUSIONS
  These results imply that HbA(1c)<7.0% will predict good blood glucose control in CF as in type 1 diabetes. However, although HbA(1c) predicts complications in type 1 diabetes, further studies are required to establish the relationship between HbA(1c) and diabetic complications in people with CFRD.
authors.affiliation: Cardiac and Vascular Sciences (Respiratory), St George's, University of London, Cranmer Terrace, London, SW17 0RE, UK.
authors.forename: Amanda L
authors.initials: AL
authors.lastname: Brennan
authors.forename: Khin M
authors.initials: KM
authors.lastname: Gyi
authors.forename: David M
authors.initials: DM
authors.lastname: Wood
authors.forename: Margaret E
authors.initials: ME
authors.lastname: Hodson
authors.forename: Duncan M
authors.initials: DM
authors.lastname: Geddes
authors.forename: Emma H
authors.initials: EH
authors.lastname: Baker
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D003550:Cystic Fibrosis / Q000097:blood* / Q000150:complications; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D008297:Male; D011379:Prognosis; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin