Cystic Fibrosis Related Diabetes

Abstract

Cystic fibrosis related diabetes (CFRD) is a common co-morbidity of cystic fibrosis. It is associated with diminishing lung function, poorer nutritional state, and a worse prognosis and its early diagnosis and treatment is important. In addition, the adverse pulmonary effects of CFRD may be present for up to 10 years prior to diagnosis. Prevalence increases with age from 1 to 2% below 10 years of age, 20% of adolescents and 40-50% by adulthood, and up to 90% of adults with CF will have some degree of glucose intolerance by 40 years of age. Although its pathophysiology is not well understood, the primary cause is thought to be the fatty infiltration of the pancreas leading to fibrosis and destruction of the pancreatic cells resulting in beta cell destruction and progressive insulin deficiency. Oral glucose tolerance testing (OGTT) remains the method of choice for a diagnosis of type I, type II and gestational diabetes; it is less discriminating in CFRD where early glucose trends are important, and continuous glucose monitoring may prove a more useful diagnostic and management tool. Diabetic complications occur in CFRD and annual screening for these is necessary. As life expectancy rises, diabetic complications may become more prevalent. This chapter discusses the diagnosis and treatment of CFRD and touches on devel‐ opments in research which will enhance the future management of this increasingly common and important manifestation of the CF condition.