Diabetes Mellitus Treatment

In patients diagnosed with diabetes mellitus (DM), the therapeutic focus is on preventing complications caused by hyperglycemia. In the United States, 57.9% of patients with diabetes have one or more diabetes-related complications and 14.3% have three or more.[1] Strict control of glycemia within the established recommended values is the primary method for reducing the development and progression of many complications associated with microvascular effects of diabetes (eg, retinopathy, nephropathy, and neuropathy), while aggressive treatment of dyslipidemia and hypertension further decreases the cardiovascular complications associated macrovascular effects.[2-4] See the chapter on diabetes: Macro- and microvascular effects.

Glycemic Control

Two primary techniques are available to assess a patient’s glycemic control: Self-monitoring of blood glucose (SMBG) and interval measurement of hemoglobin A1c (HbA1c).
Self-Monitoring of Blood Glucose

Use of SMBG is an effective method to evaluate short-term glycemic control. It helps patients and physicians assess the effects of food, medications, stress, and activity on blood glucose levels. For patients with type 1 DM or insulin-dependent type 2 DM, clinical trials have demonstrated that SMBG plays a role in effective glycemic control because it helps to refine and adjust insulin doses by monitoring for and preventing asymptomatic hypoglycemia as well as preprandial and postprandial hyperglycemia.[2,5-7]

The frequency of SMBG depends on the type of medical therapy, risk for hypoglycemia, and need for short-term adjustment of therapy. The current American Diabetes Association (ADA) guidelines recommend that patients with diabetes self-monitor their glucose at least three times per day.[8] Those who use basal-bolus regimens should self-monitor before each meal and at bedtime (four times daily). Initially some patients require more frequent monitoring, including both preprandial and postprandial readings. Patients with gestational diabetes who are taking insulin should monitor their blood glucose three or more times daily. Patients should be educated on how to use real-time blood glucose values to adjust their food intake and medical therapy. Recently several companies developed continuous glucose monitors (CGM) that measure interstitial glucose levels and have been shown to improve glycemic control without increasing the risk of hypoglycemia. Patients still need to check their blood glucose levels two times a day to calibrate the CGM device.

It is commonly recommended that patients with type 2 DM who use insulin self-monitor their blood glucose levels, but the evidence to support the effectiveness of this practice is inconclusive. Initial studies showed that SMBG in type 2 DM patients reduced HbA1c, but the inclusion of health-improving behaviors, such as diet and exercise, in many of the analyses made it difficult to assess the degree of contribution of SMBG.[2,9] Follow-up studies that attempted to correct for this did not find a significant improvement in glycemic control after 12 months.[10,11]