Metformin Tops Sulfonylureas for Heart Health

The diabetes drug metformin offers more heart benefits than medicines in the sulfonylurea class, according to new research from Vanderbilt University. Cardiovascular disease is the leading cause of death in those with diabetes, with more than two-thirds of people with the condition dying of heart disease or stroke.


To compare the effects of metformin (brand name Glucophage and others) and sulfonylureas (glyburide [Diabeta, Glynase, Micronase], glipizide (Glucotrol), glipizide extended-release [Glucotrol XL], glimepiride [Amaryl]) on cardiovascular outcomes such as heart attack, stroke, and death, researchers looked at the charts of more than 250,000 veterans receiving health care at Veterans Health Administration hospitals across the United States. All subjects had Type 2 diabetes, and all had been started on either metformin or a sulfonylurea — either glyburide or glipizide, in this case of this study — for their condition. Roughly 155,000 took metformin, while approximately 100,000 were on a sulfonylurea.

After reviewing about a year’s worth of data on each participant, the researchers discovered that those who had been prescribed metformin had a lower risk of heart attack, stroke, and death than those who were prescribed a sulfonylurea, with those on metformin facing a 21% lower risk of being hospitalized due to a cardiovascular condition.

“We demonstrated that for every 1,000 patients who are using metformin for a year, there are two fewer heart attacks, strokes or deaths compared with patients who use sulfonylureas. I think this reinforces the recommendation that metformin should be used as the first medication to treat diabetes” noted lead author Christianne L. Roumie, MD, MPH.

The researchers noted that they could not determine whether metformin offers heart benefits or whether sulfonylureas pose a specific heart risk, adding that both could be possible. Limitations of the study include that subjects were not compared to a control group that was not taking oral medicines, and that 97% of the participants were males and 75% were white (meaning that researchers do not know whether the findings apply to women and racial minorities).

For more information, read the article “Popular Diabetes Meds Put to the Test,” or see the study’s abstract in the Annals of Internal Medicine. And to learn more about metformin, see our many pieces on the medicine.

Learn more about the health and medical experts who who provide you with the cutting-edge resources, tools, news, and more on Diabetes Self-Management.
About Our Experts >>

  • David Spero RN

    Thanks, Diane. The only reason I can see for anyone to prescribe or take sulfonylureas now is because they are cheap.

  • jim snell

    excellent article and data on metformin.

    I am not surprised as it is critical to keeping liver excess glucose riots under control on my body.

    ahmen to that.

  • Deb

    Metformin is working great for me so far. I’m glad to hear about the heart benefits. Wish my husband could still be on it.

  • jim snell

    One most important issue issue re:metformin is its operation:

    a) metformin slows the glucose release at source – liver as well as senitizing the insulin response in other tissues. This reduces the amount of glucose that has to be absorbed – taken from blood stream.

    b) sulfonylureas boot pancreas to increase the insulin being produced helping to absorb more into the skeletal muscles. Here again, one has to burn this excess off – sufficient exercise to prevent muscles being topped off -loaded to the hilt.

  • Ferne

    If only the side effects weren’t so offensive. I have to make my appts around the times I take metformin or if I can’t avoid such a time I have to wait and take it afterwards. This seems to affect so many diabetics.

  • Krishna Kumar Pillalamarri

    This is in response to comment from David Spero:

    I take 3 x 500mg Metformin a day, and my doctor has enforced further doses of Onglyza and Glimeperide (3 x 1 mg a day) since my diabetes was not being controlled by Metformin alone. In addition I exercise daily as well. The point I am making is that Metformin is not adequate in all cases. It worked for a while, and plateaued off.


    Metformin is the dietbetic medicine that I take on
    a regular basis twice a day, I just recently went
    back to work and getting my medication is really
    expensive, if there is a way to get samples or a
    discount remedy for low price Metformin it would
    be appreciated. Thanks.

  • lakshmi

    Is trajenta 5 mg is a good tablet to diabetes,and tell me the composition and how it works

  • Gisela Gomez

    I have a question? I can not take metformin becouse gives me diarrea why this happen? thsnk you.

  • 2sweet4me

    Once again another study based upon 97% male & 75% which were white!!! As a white female taking Metformin for the past 7+ yrs & managing my glucose levels very nicely, I find these studies very suspect in the over-all health of women. When will ‘women’, white or otherwise become important enough to do a longitundinal study re the benefits and/or risks in use of Metformin or any other oral diabetes medication?? As in cardiac risks & research were based on men, w/ thoughts & findings would correlate to women, but that has been found to be very false information. Women’s cardiac risks & symptoms are very different from men. Stop making MEN the top ‘priority’ subject matter & the ‘gold-standard’ for what benefits women. Women are important too!!

  • 2sweet4me

    Another comment from me. I work really hard to maintain a healthy glucose level. My last A1C was 5.3 in June 2012. I have recently lost 7# & am hoping this makes another positive difference in my diabetes care. See my Endocrinologist on 11/26 & hope for a decrease in my Metformin dosage. Last evening I heard that my cousin of 57-yrs old (2-yrs younger than I)had a massive stroke, is totally paralyzed on his right side, minimal speech, etc & will most likely require long-term care for his remaining days. He was hypertensive & insulin dependent, but sadly did not care for himself & abused his body w/ street drugs & alcohol. So very tragic. I can only imagine what thoughts are going through his brain now that he is trapped in his body. So, so very sad. I am just over-whelmned w/ this news.

  • regina

    I take both and never had any prmyoblems. On the other hand, my sister takes the same thing but she’s been in and out of the hospital 12 times while taking both. She has gotten very small and I’m losing weight like a normal person. I would like to lose weight a little faster. I feel fantastic taking both no matter how chubby I am. My A1c is 6.00 . My heart is fine, my cholesterol is normal, my BP is 120/50. I don’t have any medical problems for the exception of my teeth, that was damaged by the dentist while serving in the military.

  • Julia Eulenberg

    Sadly, I was taken off of Metformin and moved over to insulin. I had a rare reaction to metformin–elevated lactic acid levels. Had been very sick (some kind of virus) and doubled my metformin dose to 2000 mg/day. Among other things, I had the rare reaction. The insulin seems to be working out for me, but it was a bit scary for about a week there as I nearly lost the ability to walk and had temps 4 degrees over normal.

  • Sandra Maxwell

    I was diagnosed in 2003 as being a diabetic and put on Metformin. I am still on it and I feel very good with it. My doctor has suggested that if my cretin does not change soon, he will may want to toss out the Metformin and go another way. I do not want to change my med. So, I’m drinking a lot more liquids which should help.

  • Richard Gessford

    I test 3X a day ,have been for the last ten year’s now medicare tell me that they will only give strip to test once a day. what good this ! My Doc and I have fill out the Forms and still once a day.Is the Diabetes Ass. working on this

  • kathie howard

    love to hear from other dietbetics

  • dorothy

    A few years I was prescribed metaformin and had a very bad reaction. First gas would built up in my body and any bowel movements smell like sewer gas. I tried the medicine for about 2 months then decided if this medicine would cause this severe oder what was it doing to the in side of my body. I told my doctor I would not take it. Later on a newspaper article revealed that my doctor had receive over $300,000 for promoting this drug. These bonus should not be allowed. So check if your doctor isn ‘t doing the same game