Review Article

Type 2 Diabetes Mellitus: Managing Hemoglobin A1c and Beyond

Authors: Grant C. Fowler, MD, Deepa A. Vasudevan, MD

Abstract

Comprehensive glycemic control, as demonstrated by desirable glycated hemoglobin A1c (HbA1c), postprandial glucose (PPG), and fasting plasma glucose (FPG) levels, is imperative for managing patients with type 2 diabetes mellitus (T2DM). It is important to minimize fluctuations in blood glucose levels, as they are thought to contribute to both the microvascular and macrovascular complications. The HbA1c measurement itself is not always indicative of the magnitude or frequency of glucose fluctuations during the course of a day. Therefore, treatment should be aimed at reducing not only HbA1c, but also PPG and FPG in order to achieve glycemic control. At the same time, patient safety should be a priority. Glycemic control also means minimizing hypoglycemic episodes, which elevate the risk for additional complications. In addition to being life-threatening, hypoglycemia may cause hypoglycemia unawareness and compromised counterregulatory mechanisms. It may also lead to serious short- and long-term effects, including cognitive impairment and dementia. As most patients are unable to maintain glycemic control on monotherapy, fortunately, effective combination regimens are available with agents having complementary mechanisms that act upon HbA1c, PPG, and FPG with minimal risk of hypoglycemia or weight gain.

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