CYSTIC FIBROSIS-RELATED DIABETES

Abstract

Introduction: Cystic Fibrosis-Related Diabetes (CFRD) is classified as a specific type of diabetes due to disease of the exocrine pancreas. It is estimated that 15-30% of adults with Cystic Fibrosis (CF) develop CFRD, and the risk of Diabetes Mellitus (DM) in CF is 20 times higher than in the general population. Although it is not as highly prevalent as type 1 DM and type 2 DM, early diagnosis and treatment of CFRD are also essential to prevent complications and reduce morbidity and mortality in patients with this disease. Objective: To conduct a literature review on DM as a comorbidity of Cystic Fibrosis. Methods: Literature review by searching the terms "Cystic fibrosis", "Diabetes" from PubMed and Scielo of the most relevant articles of the last 15 years. Results and Discussion: CFRD is the most common extrapulmonary comorbidity in people with CF. The main risk factors are female gender and advancing age. CFRD is associated with increased frequency of pulmonary exacerbations, greater reduction in lung function, and poorer nutritional status. Genetic variants in the CFTR gene cause depolarization of β cells, interfering with insulin release and causing postprandial hyperglycemia; reduction in the volume of islets; increased protein concentrations in the pancreatic duct, leading to its obstruction; oxidative stress, among other effects. Therefore, postprandial hyperglycemia alone, ESRD without fasting hyperglycemia, and ESRD with fasting hyperglycemia may develop, and these categories may be switched between. CFRD screening is recommended annually from 10 years of age in patients with CF. The most used test for screening and diagnosis is the Oral Glucose Tolerance Test (OGTT). The treatment is multidisciplinary, based on insulin therapy and, in addition, a high-calorie diet is recommended. Conclusion: In patients with CFRD, complications, especially pulmonary exacerbations, are more frequent. The diagnosis is challenging due to the dynamic profile of blood glucose in these patients and, to date, there are no specific cut-off points for CFRD, and diagnostic parameters based on data from adults with type 2 DM are used.