EVALUATION OF GLUCOSE-TOLERANCE AND INSULIN-SECRETION IN CYSTIC-FIBROSIS PATIENTS

Blood glucose profile and insulin levels during the oral glucose toler ance test were retrospectively analyzed in 52 cystic fibrosis (CF) pat ients aged 10-33 years (mean 18 years). Thirty-seven subjects (71.1%)h ad normal glucose tolerance; 6 patients (11.5%) had impaired glucose t olerance and 9 patients (17.3%), with fasting blood glucose levels bel ow 7.2 mmol/l were classified as diabetic, according to WHO diagnostic criteria. No significant differences in the total amount of secreted insulin (expressed as area under the curve) were detected in CF patien ts with or without glucose intolerance, but a significant delay in the insulin peak time appeared to be related to a compromised nutritional status. Our data indicate a significantly increased risk of glucose m etabolism impairment related to poor nutritional condition (RR 5.40; 9 5% CI: 1.5-19.7) and worse clinical status (RR 4.27; 95% CI: 1.05-17.2 ). In particular, glucose tolerance abnormalities were found in 50% of CF patients with an unsatisfactory nutritional condition versus 15.6% of CF patients with good nutritional status. Conclusions: Since CF-re lated diabetes is often underdiagnosed and associated with deteriorati on in patients' overall clinical status, it is very important to ident ify subjects at risk of developing diabetes by strict monitoring of gl ucose metabolism when deterioration in nutritional and clinical condit ions is seen which cannot be otherwise explained.