HbA1c levels are better predicted by prebreakfast than postbreakfast blood glucose self-analyses in type 2 diabetes. Influence of duration of diabetes and mode of treatment.Acta Diabetol. 2007 Jun; 44(2):55-9.AD
The present study aimed at assessing the capability of both prebreakfast and postbreakfast home blood glucose self-analyses to predict HbA1c in type 2 diabetic individuals and the influence of duration of diabetes or mode of treatment in this regard. Two hundred and twenty-seven type 2 diabetic individuals consecutively attending our diabetes clinic between January 2000 and December 2002 (42.3% placed on oral drugs and 57.7% receiving insulin therapy, either alone or as a combination with oral drugs) were retrospectively selected and three more recent values regarding both home prebreakfast and one-hour postbreakfast blood glucose self-analyses were averaged. Patients were classified by their mode of treatment (submission or not to insulin therapy) and by quartile of duration of diabetes. The correlations of HbA1c levels with either prebreakfast or postbreakfast blood glucose self-analyses were performed in the whole group and in every subset considered. HbA1c values had a stronger correlation with prebreakfast blood glucose self-analyses (r=0.53, p<0.001) than with one-hour postbreakfast home glucose self-analyses (r=0.39, p<0.001). Prebreakfast (but not onehour postbreakfast) blood glucose self-analysis was selected as independently associated to HbA1c levels in a multiple regression analysis performed upon the whole study group as well as in most of the subsets considered. HbA1c values had a stronger correlation with prebreakfast glucose self-analyses in individuals with a shorter duration of diabetes (r=0.71, p<0.001) and not submitted to insulin therapy (r=0.59, p<0.001). Increasing age characterised individuals with the highest postbreakfast glucose excursions (one-way ANOVA, p<0.01). These data suggest that prebreakfast blood glucose self-analyses are more closely related to HbA1c levels than one-hour postbreakfast blood glucose self-analyses in most of the clinical spectrum of type 2 diabetes mellitus.