[Features of glycemic variability in men with different types of obesity]

Obesity generally determines the metabolic basis for the development of type 2 diabetes. Therefore the analysis of glycemic variability in obese individuals, especially in its different phenotypes, acquires particular relevance.

To investigate the features of glycemic variability in men with different adipose tissue distribution topography within usual dietary conditions.

The study enrolled 43 men aged 25-65 years. Group 1 (n=17) represented obese men with subcutaneous fat distribution (SFD) while group 2 (n=16) consisted of obese men with abdominal fat distribution (AFD) and group 3 (comparator) included 10 male subjects with normal body weight (NBW). A 2-day continuous glucose monitoring (CGM) under condition of usual diet, work and physical activity was performed in each study subject. A number of parameters, indices and ratios had been assessed describing glycemic variability (GV) for daytime (6.00-23.59) and night (0.00-5.59) hours.

Comparative analysis of key parameters and indices describing daytime and night GV in NBW and obese men without fat distribution adjustment did not reveal statistically significant differences. After fat distribution adjustment  significantly higher mean glucose levels, standard deviation of glycemic levels and coefficient of variation were found in AFD group; also statistically significant differences were revealed in CONGA index and J-index. An analysis of the LBGI and HBGI indices that are respectively reflecting the risks of hypo- and hyperglycemia showed that the LBGI index was higher in obese men with SFD while the НBGI index was higher in men with AFD. A comparative analysis of GV parameters showed that daytime indicators values were significantly higher relative to nighttime. However the ambiguous changes in the mean glucose levels was found between study groups. Specifically in NBW men daytime and nighttime glycemia didn't differ, whereas in AFD group there was a trend to decrease in night glucose levels (p = 0.08) while in men with SFD night decrease in glycemia became statistically significant (p=0.005).

Results of glycemic variability assessment in obese men suggest that abdominal and subcutaneous types of fat distribution are associated with specific features of carbohydrate metabolism and determine different risk levels for developing type 2 diabetes in patients with AFD and SFD.