Role of HbA1c in management of diabetes mellitus

OBJECTIVE: To represent that glycosylated hemoglobin (HbA1c) is not requested by the physicians in spite of its critical importance in the monitoring of glycemic control and prediction of complications due to diabetes.

METHODS: A cross-sectional study was conducted at the outpatient department of King Abdul-Aziz University Hospital, Jeddah, Kingdom of Saudi Arabia, between October 2002 and July 2003. Out of the 265 known patients with diabetes, 130 patients were included in the study, which had HbA1c levels registered in their medical records. Demographic features, smoking habit, presence of hypertension, hyperlipidemia were recorded. Detailed information on diabetes were recorded, which included duration, type (type I or type II) and pattern of treatment, degree of glycemic control (assessed by two-points blood sugar and HbA1c levels). Screening for microvascular complications was recorded.

RESULTS: Only 130 (49%) of the patients with diabetes were included in the study. Poor control was detected in the majority of the patients with diabetes. There was a difference in the detection of poor glycemic control by both methods; HbA1c levels showed poor control in 77% of the patients and by the two-point blood sugar (2-PBS) methods in 69% of the patients. Only 70% of the patients with poor glycemic control by HbA1C showed poor control by 2-PBS (p=0.7). Poor control was detected in 45% of the patients using insulin by measuring HbA1c levels, and by measuring 2-PBS in 34% of the patients (p=0.005, p=0.16). A significant relation was found between HbA1c levels, retinopathy and nephropathy (p=0.02, p=0.05).

CONCLUSION: Guidelines of the American Diabetic Association (ADA) regarding proper management of patients with diabetes should be followed to achieve the recommended outcome. Glycosylated hemoglobin levels should be checked every 3 months. Physicians and patients must be advised not to depend solely on 2-PBS results, especially for insulin dependant diabetics.