Chronic obstructive pulmonary disease is a multifactorial disease characterized by gene-gene interaction as well as environmental effects. The incidence of type 2 diabetes mellitus is proved to be higher in the presence of chronic obstructive pulmonary disease than in the case of its absence.

We aimed to study the genotypes of MDR1 (C3435T) gene polymorphism and its relationship with clinical, instrumental, and laboratory parameters in chronic obstructive pulmonary disease associated with type 2 diabetes mellitus.

All the patients were divided into two groups. The first group included 53 patients with chronic obstructive pulmonary disease, and the second group included 49 patients with chronic obstructive pulmonary disease with comorbid type 2 diabetes mellitus. The COPD assessment test (CAT), 6-minute walk test, BODE integral index, spirometry, and bioimpedansometry were used for examination. Lipid spectrum, carbohydrate metabolism, endothelial functional status, leptin, adiponectin, and serum levels were also determined by means of enzyme immunoassay.

Our study results showed no significant difference between the genotypes of the control group of healthy individuals and patients with chronic obstructive pulmonary disease and comorbid type 2 diabetes mellitus. Though, a certain association of this gene polymorphism with clinical findings by CAT-test, specific parameters of carbohydrate (fasting glucose) and lipid metabolism (total cholesterol and low-density cholesterol lipoproteins), endothelial functional state (nitrate/nitrite level) with the minor allele T available was found.