GCK-MODY diabetes course in persons over 18 years of age: prospective observation

Abstract

Most young patients with hyperglycemia have type 1 diabetes and type 2 diabetes but up to 10% of all cases of the disease occur in MODY (Maturity Onset Diabetes of the Young). Published abstracts show features of the debut, laboratory and genetic characteristics of MODY in the Russian population. However there is a small amount of data on the clinical course of this nosology in the Russian Federation.Aim: To investigate the characteristics of the 3-year course of GCK-MODY diagnosed after 18 years.Materials and methods: 85 probands and 46 relatives of the first and second degrees of kinship with a clinical diagnosis of GCK-MODY were examined: biochemical and hormonal blood tests, ultrasound, molecular genetic studies. Patients were invited for a follow-up visit 3 years after verification of the pathogenic mutations associated with GCK-MODY. Examination, biochemical and hormonalanalyzes , ultrasound were done in second visit.Results: The diagnosis GCK-MODY was verified by a molecular genetic study in 25 probands (29.4%). In 33 of 46 (71.7%) relatives of patients with GCK-MODY were diagnosed identical mutations. In 31 patients with GCK-MODY diagnosed after 18 years, a dynamic observation was performed for three years. Most patients over 18 years of age did not have clinical manifestations of carbohydrate metabolism disorders when diagnosing GCK-MODY and follow up visit. Skin rashes and allergic reactions prevailed among concomitant pathologies. Patients with GCK-MODY had preserved β-cell secretion, HbA1c targets were achieved. Low fasting hyperglycemia prevailed which persisted even after treatment correction. Among the characteristics of carbohydrate metabolism, biochemical, lipid and hormonal parameters during GCK-MODY verification and after three years of observation no significant differences were obtained, which indicates a stable course of the disease. Half of the patients achieved normoglycemia by rational nutrition, two people with GCK-MODY within three years after determining the diagnosis were transferred from insulin therapy to oral glucose-lowering drugs. Among oral glucose-lowering drugs prior to GCK-MODY verification most patients used metformin, 3 years later — dipeptidyl peptidase-4 inhibitors.Conclusion. The results of a three-year follow-up of a group of patients with GCK-MODY demonstrate a non-progressive course of this type of diabetes with stable indicators of carbohydrate metabolism and low fasting hyperglycemia that persists after 3 years of observation. With the verification of GCK-MODY and the achievement of the target values of glycated hemoglobin and postprandial glycaemia by rational nutrition, even if a low level of fasting hyperglycemia is determined, the prescription of oral glucose-lowering drugs is not indicated in most cases.