SUN-696 Effect of Night Shifts on Glycemic Variability in Patients with Type 2 Diabetes

The analysis of indicators of carbohydrate metabolism and variability of glycemia in patients with type 2 diabetes mellitus working in night shifts was carried out. As model patients with impaired circadian rhythm, the study included 34 patients, railway transport drivers, with shift mode and the presence of night shifts, with work experience of more than 5 years, the duration of type 2 diabetes mellitus (DM2) from 1 to 7 years, who are on oral therapy with hypoglycemic drugs. Simulation of different working conditions (day-night) was carried out in the simulator “driver’s cabin”. All patients underwent a study of the main indicators of carbohydrate metabolism (fasting glycemia, postprandial glycemia, glycated hemoglobin (HbA1c)), as well as continuous daily glucose monitoring (CGMS) using Medtronic MiniMed iPro2 system (from 3 to 7 days). Target glycemic levels were not achieved: fasting glycemia was 6.98±1.41 mmol/l; postprandial glycemia was 9.57±1.65 mmol/l; HbA1c was 7.23±1.62%. The analysis of CGMS revealed high variability of glycemic index MAGE-4.88±0.59 mmol/l. also calculated indicators SD - 1.52±0.63 mmol/l; Conga - 3.17±0.54 mmol/l; MODD - 2.27±0.12 mmol/l. The period of hyperglycemia (glucose value above 7.8 mmol/l) according to the results of CGMS was 43.5% (min 19-max 56). The duration of hypoglycemic States in patients without night shifts was 2.4% within 24 hours (min 0-max 6.6). Correlation analysis between carbohydrate metabolism and glucose variability revealed a significant strong relationship between the level of postprandial glycemia and modd (r=0.87, P=0.001) and MAGE (r=0.82, P=0.01), and also established a mean significant correlation between the level of postprandial glucose and Conga (r=0.52, P=0.01) and SD (r=0.61, P=0.05). Fasting glycemia and congas were moderately correlated (r=0.4, P=0.01). Weak reliable correlation was found only between HbA1c level and Conga variability index (r=0.27, P=0.04). Conclusions: the results of the study indicate the lack of adequate glycemic control in persons working night shifts, high variability of glycemia, which is an independent risk factor for cardiovascular disease in patients with DM2. The associative relationship of fasting glycemia and postprandial with the indicator of variability Conga shows that glucose fluctuations during the day in patients are constant.