ACP recommends metformin as first-line therapy for type 2 diabetes

Physicians should prescribe oral metformin as a first-line therapy for most patients with type 2 diabetes, as well as for those whose blood sugar cannot be controlled with diet, exercise, and weight loss, according to new guidelines from the American College of Physicians (ACP).

The guidelines, published in the February issue of Annals of Internal Medicine, also recommend adding a second drug when monotherapy and lifestyle modifications do not control a patient’s disease.

The recommendations, written by ACP’s Clinical Guidelines Committee, led by Amir Qaseem, MD, PhD, MHA. ACP in Philadelphia, are based on two 2011 literature reviews lead by Wendy L. Bennet, MD, MPH, The Johns Hopkins University School of Medicine.

There are 11 different classes of drugs approved by FDA for the treatment of type 2 diabetes. All vary in cost and risk, and most patients with diabetes will receive more than 1 class of medication, the authors wrote. Therefore, in reviewing available data from 1996 through April of 2010, they sought to establish best-practice management strategies for the disease.

The new guidelines are graded according to the ACP clinical practice guidelines grading system. They are based on high-quality evidence gathered from a systematic evidence review, which evaluated English-language published literature using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials.

The outcomes assessed for the guidelines included all-cause mortality, cardiovascular morbidity and mortality, cerebrovascular morbidity, neuropathy, nephropathy, and retinopathy. All the recommendations are considered strong.

The authors concluded that metformin is an effective management strategy because it is cheaper than most other drugs, appeared more effective, and was associated with fewer side effects.

“The evidence shows that most diabetes medications reduced HbA1c levels to a similar degree,” the authors wrote. “Metformin was more effective than other medications as monotherapy as well as when used in combination therapy with another agent for reducing HbA_1c levels, body weight, and plasma lipid levels (in most cases).”

There was insufficient evidence to point to any difference in the effectiveness of medications by age, sex, or race.