Objective: To determine the association of insulin sensitivity and pancreatic beta-cell function parameters assessed by the homeostasis model assessment (HOMA) and glycemic control, and their potential utilization in the clinical care of patients with type 2 diabetes mellitus.
Material and Method: The HOMA indices were assessed in 204 (62 males, 142 females) type 2 diabetic outpatients aged 60.7 + 10.9 years. All patients were non-insulin treated for their diabetes. The correlation between variables including logarithmically transformed HOMA-%S and HOMA-%B, body mass index (BMI) and duration of diabetes to glycemic control were assessed. The value of the disposition index (HOMA-%SxHOMA-%B) that best discriminated patients with good glycemic control (HbA1C < 7%) from those without (HbA1C > 7%) was determined.
Results: Both log (HOMA-%S) and log (HOMA-%B) were inversely related to HbA1C with comparable degrees of association (beta = -0.62, p < 0.001 and beta = -0.61, p < 0.001, respectively). The log-transformed disposition index of at least 3.57 had a sensitivity of 74.2% and a specificity of 67.6% in classifying patients as having HbA1C < 7%. The result suggested that in order to achieve acceptable glycemic control, oral hypoglycemic agents should be adjusted to maximize the likelihood of the log-transformed disposition index reaching 3.57.
Conclusions: Glycemic control in diabetic patients partially depends on both insulin sensitivity and pancreatic beta-cell function. Assessing both parameters with the HOMA model is likely to result in a more rational approach for achieving better glycemic control in type 2 diabetic patients. 

Keywords: Homeostasis model assessment (HOMA),Glycemic control, T2DM