News & Research

Metformin establishes itself as an effective and safe medication in people with type 2 diabetes and kidney dysfunction. By Nils Ekström and colleagues. BMJ Open 2012;2:e001076

What is the problem and what is known about it so far?

Metformin is often the first medication prescribed to people with type 2 diabetes because of its long track record of safety and efficacy. However, there are concerns that metformin raises the risk of lactic acidosis, the buildup of lactic acid in the blood that can cause nausea and weakness, particularly in people with heart and kidney problems for whom the risk for lactic acidosis is already raised.

Why did the researchers do this particular study?

Because metformin has proven itself such a beneficial medication, the researchers wanted to determine the long-term effects of metformin relative to other treatment options in a wide swath of people, including those with kidney issues.

Who was studied?

The researchers studied 51,675 men and women with type 2 diabetes who were registered in the Swedish National Diabetes Register and taking glucose-lowering medications.

How was the study done?

Doctors monitored patient health between 2004 and 2010, tracking the incidences of death, heart disease, and acidosis, along with medication use. The researchers analyzed the data to determine how different medications altered the risk for these various health issues.

What did the researchers find?

The study’s participants who took metformin were at a lower risk for heart disease, acidosis, and death than insulin users. Metformin use was also associated with a lower risk of death than other oral blood glucose–lowering medications, such as sulfonylureas. When looking at only those patients with kidney dysfunction, metformin performed the same as it did in the wider population.

What were the limitations of the study?

There were only 8 cases of lactic acidosis among the participants, so the conclusions regarding acidosis are not statistically strong. Also, the researchers were unable to monitor whether certain participants switched medications during the study, which may have affected the results.

What are the implications of the study?

The study’s authors conclude that doctors can take a less strict approach to prescribing metformin to people with kidney problems, offering up the possibility that many more people with type 2 diabetes can have access to this drug.

FOR MORE INFORMATION

Diabetes A to Z, 6th Edition

Metformin: A New Shine on an Old Medication

Metformin Is the First Choice in Type 2 Meds