An investigation of the usefulness of HbA1 as an index of control of diabetes: from the viewpoint of progress of diabetic retinopathy.
To suppress the progression of diabetic microangiopathies, good control of blood glucose levels must be maintained. We examined the usefulness of glycosylated hemoglobin as an index of control of diabetes using the Markov process for the analysis of the prognosis of retinopathy. Two hundred and ninety-nine diabetics who were followed for over 3 years period in our clinic and whose control states were steady during the observation period were selected for this study. Grade of retinopathy was classified into 4 stages according to Scott's criteria (Stage 1: no retinopathy, Stage 2: Scott Ia and IIa, Stage 3: Scott IIIa and IIIb, Stage 4: Scott IV and V). Glycosylated hemoglobin was measured as Hemoglobin A1 (HbA1), and patients were divided into 4 groups according to their levels of HbA1: Group A: HbA1 less than or equal to 8%, Group B: 8% less than HbA1 less than or equal to 10%, Group C: 10% less than HbA1 less than or equal to 12% and Group D: 12% less than HbA1. We estimated the transitional probability for the course of retinopathy from Stage 1 to Stage 4. After 10 years, Group A was expected to distribute to Stage 1 67%, Stage 2 29%, Stage 3 3% and Stage 41%, Group B to Stage 1 49%, Stage 2 45%, Stage 3 5% and Stage 4 1%, Group C to Stage 1 53%, Stage 2 30%, Stage 3 12% and Stage 4 4%, and Group D to Stage 1 24%, Stage 2 36%, Stage 3 23% and Stage 4 16% respectively (P less than .001).(ABSTRACT TRUNCATED AT 250 WORDS)
D001786:Blood Glucose / Q000032:analysis; D003920:Diabetes Mellitus / Q000097:blood; D003930:Diabetic Retinopathy / Q000097:blood*; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D011379:Prognosis
D001786:Blood Glucose; D006442:Glycated Hemoglobin