Two widely used medicines for type 2 diabetes may carry greater risks for the heart than many people realize, according to a new study from Northwestern University.
The researchers found that two older treatments, called sulfonylureas and basal insulin, were linked to a higher chance of serious heart-related health problems than several newer diabetes medicines.
The study was published in JAMA Network Open.
Type 2 diabetes happens when the body cannot use insulin properly, causing blood sugar levels to stay too high. Over time, high blood sugar can damage blood vessels and organs, increasing the risk of heart disease, kidney disease, vision loss, and other serious health problems. Keeping blood sugar under control is an important part of reducing these risks.
For most people, treatment begins with metformin. This medicine has been used for many years because it is effective, affordable, and has a strong safety record. However, some people cannot take metformin because of side effects or other health conditions, while others need another medicine because metformin alone is no longer enough.
Doctors can choose from several medicines when a second treatment is needed. In many countries, sulfonylureas and basal insulin remain popular because they usually cost much less than newer drugs. Even so, there has been ongoing debate about whether these older medicines are as safe for the heart as newer options.
The Northwestern team examined real-world health records from more than 130,000 people with type 2 diabetes who started a second diabetes medicine after metformin. Instead of looking only at controlled clinical trials, the researchers studied how these medicines performed in everyday medical care, giving a clearer picture of what patients may experience in real life.
The results showed that people taking sulfonylureas were 36% more likely to develop major heart-related problems than people taking DPP-4 inhibitors. Those using basal insulin had an even greater risk, with about twice the chance of experiencing serious complications.
These complications included heart attacks, strokes, heart failure, and amputations. Because about 60% of patients who need a second diabetes medicine receive either sulfonylureas or basal insulin, the findings could affect a very large number of people around the world.
The researchers said doctors should carefully consider newer medicines, including GLP-1 receptor agonists, SGLT-2 inhibitors, and DPP-4 inhibitors, when choosing treatment after metformin. Although these medicines are often more expensive, they appear to offer better protection for heart health.
Lead researcher Dr. Matthew O’Brien said the findings should encourage doctors and patients to discuss all available treatment choices before deciding which medicine to use.
While controlling blood sugar remains essential, the researchers believe heart safety should also play a major role in choosing the best treatment for type 2 diabetes.
If you care about diabetes, please read studies about diabetes and vitamin B12, and the right diet for people with type 2 diabetes.
For more health information, please see recent studies about how to eat smart with diabetes, and turmeric and vitamin D: a duo for blood pressure control in diabetic patients.
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