Continuous Glucose Monitoring in Cystic Fibrosis Patients According to the Glucose Tolerance

Abstract

Cystic fibrosis (CF) is associated with a long preclinical state of abnormal glucose tolerance. The aim of this study was (i) to evaluate the profile of glucose tolerance in young adults with CF and (ii) to compare these results with those obtained by a continuous subcutaneous glucose monitoring (CGMS). CF subjects with fasting glycemia inferior to 126 mg/dl were included in the study. An oral glucose tolerance test (OGTT) identified the subjects either with a normal glucose tolerance (NGT), or impaired glucose tolerance (IGT), or diabetes. CGMS (Medtronic) was performed during 3 days to analyze mean glucose level, high glucose excursions, and glucose area under the curve (AUC). Forty-nine patients were included in the study. NGT (n=22), IGT (n=17), and diabetes groups (n=10) were comparable except with regard to age and BMI (p<0.001). HbA1c values in diabetes group were significantly higher (p<0.001) than in NGT and IGT groups. CGMS revealed peaks of glucose values superior to 200 mg/dl at least once after a meal in 8 patients (36%) with NGT, in 9 patients (52%) with IGT, and in all patients with diabetes (p<0.01). Mean CGMS glucose and glucose AUC values increased in patients with diabetes compared to patients with NGT and IGT (p<0.05). Peak of CGMS glucose reached 182+/-60 mg/dl in NGT group despite the normal glucose profile at OGTT. In conclusion, CGMS revealed pathological glucose excursions not only in patients with impaired glucose tolerance at OGTT but also in patients with a normal glycemic profile. CGMS could be a useful tool for the early detection of hyperglycemia in patients with CF.

Abnormal glucose tolerance in children with cystic fibrosis: the predictive role of continuous glucose monitoring system

“…Similar to our findings, relative to an entirely paediatric cohort, adult CF subjects with NGT at OGTT have been shown to have diabetic glucose excursions at CGMS in 33-36% of the cases (11,13). Moreover, in selected high-risk adolescents with CF and NGT or IGT, pathological CGMS glucose excursions were reported in around 50-70% of the cases (10,12).…”

“…There is now evidence that the OGTT method, evaluating fasting and 2-h postload glucose, may miss episodes of hyperglycaemia. It has been demonstrated recently that the continuous glucose monitoring system (CGMS) is a useful and valid tool in defining glucose metabolism in children and adults affected by CF with early glucose derangements (10)(11)(12)(13)(14)(15).…”

Screening for cystic fibrosis-related diabetes: a systematic review.

“…Nine studies 174,[183][184][185][186][187][188][189]205 (one in German 174 ) provided sufficient data for 2 × 2 tables with actual numbers, not just per cent, so that CIs could be produced. Full details are given in the data extraction forms in Appendix 4.…”

“…Moreau et al, 187 from Strasbourg, compared the ROGTT with CGM in 49 patients. CGM involved 288 readings of tissue glucose per day.…”

Cystic fibrosis-related diabetes: links, challenges, and future directions

“…In one study of 22 CF subjects with NGT, a peak CGM glucose level of 182 mg/dL was identified, and observed post-prandial glucose peaks .200 mg/dL in one-third of CF subjects with NGT, half of IGT subjects, and all patients with CFRD. 80 Glucose excursions .200 mg/dL on CGM successfully predicted the development of IGT or CFRD as diagnosed by OGTT in a 2.5-year period. 81 Hameed 82 confirmed the validity and reproducibility of CGM in over 100 children with CF.…”