Function of ß-cells and insulin resistance in long-standing type 2 diabetes mellitus
Introduction. Every patient with type 2 diabetes mellitus secretes less insulin than necessary for his/her level of insulin sensitivity, and many of them have some degree of insulin resistance. The mix of insulin defi ciency and insulin resistance is different for each patient and, in any patient, it may vary during the course of the disease. The aim of our study was to examine the degree of -cells function and the presence of insulin resistance in patients with a long-standing type 2 diabetes. Methods. The study included 30 patients of both sexes (12 males, 18 females), with the mean values of age 59 years (SD=7.88) and the disease duration of 10 years (SD=5.36). The mean value of BMI was 31 kg/m2 (SD=4.74). The fasting glucose and insulin concentrations and HbA1c in the blood were determined by the standard laboratory methods. The percentages of functional -cells in the pancreas (HOMA%B), insulin sensitivity (HOMA-%S) and insulin resistance (HOMA-IR) were calculated using a HOMA calculator v2.2. Then, the data were analyzed by statistical software SPSS 19. Results. The mean HbA1c was 10 % (SD=1.52) and FBG 12 mmol/L (SD=4.15). The mean insulin was 13 μmol/L (SD=6.11) and HOMA-%B 31 % (SD=18.99). The median value of HOMA-%S was 49% (32.2-82.4) and HOMA-IR 2 (1.2-3.1). 87% of patients had a HOMA-IR >1. Conclusion. The highly reduced -cells function and the consequent insulin defi ciency, usually combined with the moderate insulin resistance was determined in the patients with a long-standing type 2 diabetes mellitus.