ABSTRACT
INTRODUCTION: Insulin remains the only recommended medical treatment for cystic fibrosis related diabetes (CFRD) Whilst there is an established role for orally bioavailable incretin mimetic agents such as the dipeptidyl peptidase-4 inhibitors (DPP4-I) in Type 2 diabetes mellitus, there exists little data on their utility in CFRD. AIM: To examine the use of DPP4-I therapy in patients with CFRD at a single large adult cystic fibrosis center. METHOD: People with CFRD prescribed a DPP4-I were identified from our specialist CFRD clinic and records were retrospectively examined for indication for therapy, tolerability and effectiveness. Analysis of continuous glucose monitoring data Libre 2 was done for these patients (CGM) pre and at least 3 months post therapy was performed. RESULTS: 23 people with CF (PwCF) with a mean (SD) age of 35.0 ± 2.4 years were included in this analysis . In 21 patients DPP4-I was prescribed as a monotherapy and it was given in combination with insulin in 2 others. Indications for therapy included reactive hypoglycaemia (n = 10) post prandial hyperglycaemia (8), insulin avoidance (3), metformin intolerance (1) and unclear (1). Therapy was well tolerated with no discontinuations due to adverse effects. Significant improvements were noted in Time in Range- Pre vs Post: 78.0 [67.5 - 84.0] vs 89.0 [79.8 - 96.0]%, p = 0.005, Time above Range -Pre vs Post: 19.5 [12.5 - 30.8] vs 6.0 [2.5 - 16.5]%, p = 0.006 and glucose variability Pre versus Post: 28.3 [25.4 - 31.1] vs 26.9 [23.1 - 31.3], p = 0.021, Of the 10 subjects who initiated therapy for hypoglycaemia, 7 reported an improvement in symptoms. No significant difference was found in weight pre and post: 61.5 ± 15.0 kg vs 62.5 ± 15.3 kg, p = 0.326 or Hba1c pre vs post: 41.0 [36.0 - 53.3] mmol/mol versus 40.5 [36.8 - 47.3], p = 0.727. CONCLUSION: DPP4-I is well tolerated in CFRD and can lead to an improved glycaemic control in these patients with significant improvement in validated CGM metrics.