Got Type 1? Type 2 Rx May Not Help

Metformin not linked to improved glycemic control in overweight teens with type 1 diabetes

/ Author:  / Reviewed by: Jennifer Gershman, PharmD, CPh

(RxWiki News) For overweight teens with type 1 diabetes, good blood sugar control can be hard to come by.

A new study found that metformin (brand names Glumetza and others) — when used in combination with insulin therapy for six months — did not improve blood sugar (glucose) control in overweight teens with type 1 diabetes. Metformin is a drug commonly used to treat type 2 diabetes.

Type 1 diabetes is a chronic condition in which the pancreas produces little or no insulin. Insulin is a hormone needed to allow sugar to enter the body's cells for energy. Unlike patients with type 2 diabetes, patients with type 1 need lifelong insulin therapy (given through regular injections or an insulin pump) to survive.

Type 1 diabetes can affect many of the body's organs, including the heart, blood vessels, nerves, eyes and kidneys. But keeping blood sugar levels close to normal can dramatically reduce the risk of serious complications.

Metformin is an oral glucose-lowering drug. According to the authors of this study, past studies that looked at the effects of metformin on blood sugar control in teens with type 1 diabetes were inconclusive.

To investigate, a team of researchers led by Kellee M. Miller, PhD, of the Jaeb Center for Health Research in Tampa, FL, looked at 140 teens with type 1 diabetes. In addition to insulin, these teens were randomly assigned to receive metformin or a placebo for six months. A follow-up was then conducted after 13 weeks.

These researchers found that, despite a small drop in HbA1c that favored metformin at 13 weeks, average HbA1c levels increased about 0.2 percent in both groups after six months. HbA1c is a blood marker used to identify average blood sugar control over the span of three months.

Metformin also failed to improve a number of risk factors for heart disease, including blood pressure and blood fat concentrations, in these patients. More gastrointestinal side effects were also reported among the metformin group than the placebo group.

The drug was tied to less weight gain, lower body fat and lower total daily insulin dose among these patients, however.

Dr. Miller and colleagues noted that it's not likely that different results would have been achieved with a longer treatment period.

This study was published Dec. 1 in the journal JAMA.

The Juvenile Diabetes Research Foundation and the National Institute of Diabetes and Digestive and Kidney Diseases funded this research. Several authors disclosed potential conflicts of interest.

Review Date: 
November 30, 2015
Last Updated:
December 1, 2015