제2형 당뇨병 환자에서 공복 및 식후 혈당의 전체 혈당에 대한 기여도와 결정인자에 대한 연구

Abstract

Background and aims: Previous studies showed progressive shift in relative contribution of fasting and postprandial hyperglycemia to overall hyperglycemia with diabetes worsening. However, it has never been studied in Korean diabetic patients. In addition, there have been few studies about determinant factors in postprandial and fasting glucose levels. Therefore, we assessed the relative contributions of PHG and FHG to the overall hyperglycemia and the influencing factors on PHG and FHG in Korean patients with type 2 diabetes.

Material and methods: We enrolled 194 Korean type 2 diabetic patients which did not take insulin or α-glucosidase inhibitor. They performed a seven-point self-monitoring of blood glucose (7-point SMBG) more than once during each month for 3 consecutive months. Glucose area under the curve (AUC) above 100 mg/dL (5.5 mmol/L) was defined as AUC (total) to represent the overall hyperglycemia. The area under the curve above fasting glucose level was considered the postprandial hyperglycemia (AUC (PHG)). The fasting hyperglycemia (AUC (FHG)) was calculated as [(AUC (total) - AUC (PHG)]. The relative contributions of PHG and FHG to overall hyperglycemia were respectively defined as the proportions of AUC (PHG) and AUC (FHG) to AUC (TOTAL).

Results: The relative contribution of PHG showed a significant difference and gradual decrement according to increasing tertiles of HbA1c (55.3±5.5, 42.0±4.4, 33.5±2.8%; P(ANOVA) = 0.002, P(TREND) <0.001). And the contribution of FHG was increased progressively with increasing tertiles of HbA1c (44.7±5.6, 58.0±4.4, 66.5±2.8%; P(ANOVA)=0.002, P(TREND)<0.001). AUC (PHG) was positively correlated to age (r=0.191; p<0.01), systolic blood pressure (r=0.185; p<0.01), duration of diabetes age (r=0.185; p<0.01), C-peptide (r=0.198; p<0.01), HbA1c (r=0.282; p<0.01), and hsCRP (r=0.145; p<0.05). AUC (FHG) was positively correlated to body weight (r=0.190; p<0.01), waist circumference (r=0.185; p<0.01), C-peptide (r=0.217; p<0.01), HbA1c (r=0.658; p<0.01), alanine aminotransferase (r=0.228; p<0.01), and triglyceride (r=0.278; p<0.01) but negatively correlated to age (r=-0.146; p<0.05). Using multiple linear regression to adjust for age, sex and other covariates, only age (β=0.181; p<0.05) remained significant variables of the AUC (PHG) and triglyceride (β=0.121; p=0.048), waist circumference (β=0.216; p=0.042) show significant correlation with AUC (FHG).

Conclusions : In Korean type 2 diabetic patients, postprandial hyperglycemia predominantly contribute to overall hyperglycemia at lower HbA1c level, whereas fasting hyperglycemia is a predominant contributor to it at higher HbA1c level. Age is only independent predictors of postprandial hyperglycemiae and plasma triglyceride, waist circumference have significant correlation with fasting hyperglycemiae, respectively