Characteristics of patients with cystic fibrosis-dependent diabetes mellitus in childhood according to the register of patients with cystic fibrosis of the Russian Federation in 2021

BACKGROUND : In recent decades, the life expectancy of patients with CF has increased, which leads to an increase in the frequency of conditions associated with impaired carbohydrate metabolism. AIM : to analyze the impact of cystic fibrosis-associated diabetes mellitus (CFDM) in children and adolescents on the course of cystic fibrosis according to the 2021 register of patients with cystic fibrosis of the Russian Federation (RF). MATERIALS AND METHODS : the data of the register of patients with cystic fibrosis of the Russian Federation for 2021 were analyzed. The study included 122 patients with diabetes mellitus requiring the use of insulin — 33 children (27%) and 89 adults (73%), the average age of children was 13.5±4.1, the average age of adult. patients aged 18 years and older was 27.4±6.6. To compare the course of cystic fibrosis in patients with and without diabetes mellitus, groups were formed that were comparable in age, gender, genotype — the group of patients without diabetes included 827 patients, 33 patients made up the group of patients with CFRD using insulin. Diagnostic criteria, indicators of respiratory function, microbiological status, nature of complications, volume of therapy were compared. RESULTS : Patients with CFRD have a lower FEV1 compared to children without diabetes mellitus — M±SD FEV1 (%) 85.2±27.5 in the group of patients without diabetes mellitus and M±SD FEV1 (%) 72.4±26.0 in patients with diabetes mellitus (p < 0.016), compared in the microbiological seeding groups — a trend towards more frequent chronic growth of Pseudomonas aeruginosa 54.50% versus 39.4% in the group without CFRD. An increase in MRSA was also more often detected — 9.1% compared with the group of children without diabetes — 3.1%. Antibacterial therapy is more commonly used — inhaled in 54.6% of patients without diabetes mellitus while children with CFRD received inhaled antibiotic therapy in 75.8% (p=0.017). There was a significant difference in the used antibacterial tablet therapy (p=0.013). A significant difference in the number of patients on oxygen therapy in the group with CFRD — 12.1%, versus 3.4% without CFRD (p=0.01) confirms a more severe course of cystic fibrosis in patients with CFRD. CONCLUSION : The prevalence of CFDM with the need for insulin therapy among children in the Russian Federation is 1.3%. Cystic fibrosis-associated diabetes mellitus significantly worsens the course of cystic fibrosis in terms of lung function, the growth of gram-negative and resistant flora, the presence of severe complications and the frequent use of antibiotic therapy, which is obviously associated with frequent exacerbations of the bronchopulmonary process in cystic fibrosis in patients with developed cystic fibrosis-associated diabetes mellitus.