제2형 당뇨병 환자에서 당화혈색소와 가장 좋은 상관성을 보이는 일중 혈당치의 비교

Abstract

Background: We have designed a study to evaluate the relativ value of Capillary blood glucose measurement at different times of the day in comparison with HbA1c measurement in assessing the mean glycemic control of type 2 diabetic patients.

Methods: The 118 patients with type 2 diabetes, all of whom very regular visitors of the outpatient clinic of the Diabetic Center of the Yonsei University Hospital, were entered consecutively into the study. Three months before enrollment, the dietary habits of each participant were checked, and the patients received recommendations for continuing their usual diet throughout the entrie period of the study. The first sample was examined before breakfast at 6:00 A.M. (prebreakfast glucose and HbA1c); the second, at noon (prelunch glucose); and the third, at 5:00 P.M.(presupper glucose). The last sample was examined at 10:00 P.M. (bedtime glucose). The capillary whole blood glucose was used to determine bloodl glucose concentrations (by Surestep). A high-pressure liquid chromatography assay(VARIANT Ⅱ, BIO-RAD) was used to make all determinations of HBA1c(normal range,4~6%). Simple linear regression analysis was used to examine the relationship between capillary blood glucose and HbA1c at each time point. Multiple linear regression analysis was performed to determine which of the values of various capillary blood glucoses were significant and independent predictors HbA1c.

Results: Mean concentration of capillary blood glucose at 6 A.M. is significantly different between three groups classified by levels of HaA1c, but not at other times. Simple linear regression analysis demonstrated that R-squares between the blood glucose and HbA1c were 0.187(6:00 A.M.), 0.035(noon), 0.116(5:00 P.M.), and 0.108(10:00 P.M.). Levels of the blood glucose at 6:00 A.M.;5:00 P.M.; 10:00 P.M. were correlated with HbA1c, but that at noon was not. Multiple regression analysis demonstrated that the standardized coefficients(β) of the glucose levels at 6:00 A.M.; noon; 5:00 P.M.; and 10:00 P.M. were 0.348(P<0.05), -0.091(P=0.369), 0.168(P=0.418), and 0.013(P=0.338), respectively. Only, the blood glucose at 6:00 A.M. influenced to HbA1c.

Conclusions: In type 2 diabetes, the blood glucose at 6:00 A.M. have most strong correlation with HbA1c, and is better predictor of glycemic control than those of other times.