应用动态血糖监测系统评估不同糖耐量个体血糖稳定性的特征

Characteristics of glycemic stability in subjects with different glucose tolerance:the results of continuous glucose monitoring

目的探讨不同糖耐量个体血糖稳定性的特征。方法应用动态血糖监测系统(CGMS)对153例受试者进行连续3d的血糖监测,其中正常糖调节(NGR)组48名,糖耐量受损(IGT)组36例,新诊断2型糖尿病组(N-T2DM组)69例;IGT组包括单纯IGT(I-IGT)亚组16例和空腹血糖受损(IFG)合并IGT(IGT/IFG)亚组20例。比较CGMS监测中连续48h的平均血糖水平(MBG)及其标准差(SDBG)、平均血糖波动幅度(MAGE)及日间血糖平均绝对差(MODD)。结果①IGT/IFG亚组的MBG为(6.55±0.70)mmol/L,显著高于I-IGT组的(6.02±0.50)mmol/L(P<0.05),而两组间MAGE、MODD的差异均无统计学意义(P值均>0.05)。②IGT组的MBG为(6.31±0.67)mmol/L,显著高于NGR组的(5.37±0.55)mmol/L(P<0.05);MAGE为(3.12±1.09)mmol/L,显著高于NGR组的(2.00±0.69)mmol/L(P<0.01);MODD为(0.89±0.29)mmol/L,与NGR组(0.81±0.29)mmol/L的差异无统计学意义(P>0.05)。③N-T2DM组的MBG、MAGE及MODD均显著高于NGR、IGT组(P值均<0.01)。④N-T2DM组中,MAGE与糖化血红蛋白(HbA_1c)、MBG均不相关(P值均>0.05),与SDBG呈显著正相关(r=0.81,P<0.01);SDBG与MBG呈显著正相关(r=0.43,P<0.01)。结论①IGT伴或不伴IFG患者已存在日内血糖波动显著增大,至糖尿病阶段,日内血糖波动进一步加大,同时伴有日间血糖波动的明显增大。②HbA_1c不能反映血糖稳定性的特征,MAGE和MODD有助于准确反映日内及日间血糖的波动幅度。

Objective To investigate the characteristics of glycemic stability in subjects with different glucose tolerance by continuous glucose monitoring system（CGMS）. Methods A total of 153 individuals including 48 individuals with normal glucose regulation（NGR）, 36 patients with impaired glucose tolerance（IGT） and 69 patients with newly diagnosed type 2 diabetes patients（N-T2DM） were observed by CGMS for three days. The IGT group included 16 patients with isolated impaired glucose tolerance（I-IGT） and 20 patients with IGT combined with impaired fasting glucose（IGT/IFG）. The mean blood glucose（MBG） and its standard deviation（SDBG）, mean amplitude of glycemic excursions（MAGE）, and absolute means of daily differences（MODD） for 48 h were calculated in each individual. Results （1） The levels of MBG in the IGT/IFG group was higher than that in the I-IGT group （[6.55 ± 0.70] mmol/L vs [6. 02 ± 0. 50] mmol/L, P 〈 0.01）. However, there was no difference in MAGE and MODD levels between IGT/IFG and I-IGT group（P 〉0.05）. （2） The levels of MBG and MAGE in the IGT group were （6.31 ± 0.67） mmol/L and （3. 12 ± 1.09） mmol/L, respectively, all higher than those of the NGR group （[5. 37 ± 0.55] mmol/L and [2. 00 ± 0. 69] mmol/L, P 〈 0.01 and P 〈 0.05, respectively）. There was no difference in MODD levels between IGT and NGR groups（[0.89 ± 0.29] mmol/L vs [0.81 ± 0.29] mmol/L, P 〉 0.05）. （3） The level of MBG, MAGE and MODD in the N-T2DM group were higher than those in the IGT and NGR groups（all P 〈 0.01）.（4） No correlation was detected between HbA1 c and MAGE or MODD（both P 〉 0.05） in the N-T2DM group. MAGE was positively correlated with SDBG（r = 0.81, P 〈 0.01 ）. There was a significant correlation between SDBG and MBG（r = 0.43, P 〈 0.01）. Conclusion （1） In IGT patients, combined with IFG or not, the amplitude of intraday glycemic excursions is higher than that in NGR subjects, and much higher in diabetic patients. The amplitude of day-to-day glycemic excursions also significantly higher in diabetic patients. （2） HbA1 c can not reflect the characteristics of glycemic stability. The MAGE and MODD revealed by CGMS profile can help characterize intraday glycemic excursion and day-to-day glycemic reproducibility.