Increased glucose excursion in cystic fibrosis and its association with a worse clinical status.
BACKGROUND
Abnormal glucose tolerance is a frequent co-morbidity in cystic fibrosis patients (CF), and is associated with a worse prognosis. The objectives are to investigate (a) the relative contribution of insulinopenia and insulin resistance (IR) for glucose tolerance and (b) the association between various glucose parameters and CF clinical status.


METHODS
Oral glucose tolerance tests were performed in 114 consecutive CF patients not known to be diabetic as well as 14 controls similar for age and BMI.


RESULTS
Abnormal glucose tolerance was found in 40% of patients with CF: 28% had impaired glucose tolerance (IGT) and 12% had new cystic fibrosis related diabetes (CFRD). Compared to control subjects, all CF patients were characterized by an increased glucose excursion (AUC). While reduced early insulin release characterised CF, IGT and CFRD patients also present IR thus both mechanisms significantly contribute to glucose tolerance abnormalities. Increased glucose AUC and reduced early insulin release but not glucose tolerance categories were associated with a reduced pulmonary function (FEV(1)).


CONCLUSIONS
In CF, early insulin secretion defect but also IR contribute to glucose intolerance. Early in the course of the disease, increased glucose AUC and reduced early insulin secretion are more closely associated with a worse clinical status than conventional glucose tolerance categories.
Costa
Myriam
M
Diabetes Research group, CHUM Research Center Hôtel-Dieu, Montreal QC, Canada H2W 1T7.
Potvin
Stéphanie
S
Hammana
Imane
I
Malet
Arnaud
A
Berthiaume
Yves
Y
Jeanneret
Alphonse
A
Lavoie
Annick
A
Lévesque
Renée
R
Perrier
Joëlle
J
Poisson
Danielle
D
Karelis
Antony D
AD
Chiasson
Jean-Louis
JL
Rabasa-Lhoret
Rémi
R
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D003550:Cystic Fibrosis / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism*; D005260:Female; D018149:Glucose Intolerance / Q000150:complications / Q000378:metabolism*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D008297:Male; D011379:Prognosis; D013997:Time Factors
D001786:Blood Glucose; D007328:Insulin