The blood-glucose-lowering drug metformin may reduce risk of death from any cause by as much as 24% in people with Type 2 diabetes, according to preliminary research presented at the 2010 meeting of the American Diabetes Association. Over 100 million people worldwide are currently prescribed metformin.
Earlier studies, including the landmark United Kingdom Prospective Diabetes Study (UKPDS) from 1999, have indicated that there might be a link between metformin and reduced mortality. To investigate the potential association, researchers in France analyzed data from the Reduction of Atherosclerosis in Health (REACH) registry, which included information on over 67,000 people from 44 countries. (REACH was designed to look at potential risk-management strategies in people at risk of a cardiovascular condition known as atherothrombotic disease.) From this group, the investigators looked at 19,699 people older than age 45 who had diabetes as well as cardiovascular disease or another atherothrombotic risk factor. Forty percent of the study group was being treated with metformin; those on the medicine were generally younger, heavier, and had better kidney function.
Over two years, 1,270 people died. The researchers found that people taking metformin had a 33% decrease in risk of death compared to those not taking metformin. After adjusting for various factors, overall reduction in the risk of death was still 24%.
According to lead study author Ronan Roussel, MD, PhD, “In secondary prevention patients, the use of metformin was associated with a significant reduction in all-cause mortality after two years of follow-up… this adds to the strength of evidence that suggests a mortality benefit.”
Roussel suggested that the protective effect may apply more to women, people between the ages of 40 and 80, people with a history of heart failure, and those who are using insulin in addition to metformin. He notes that the results of this study should be explored in future research.