Type 2 diabetes is one of the most common long-term health conditions in the world. Millions of people depend on daily medications to keep their blood sugar levels under control and reduce the risk of serious complications.
If diabetes is not treated properly, it can damage the heart, blood vessels, kidneys, eyes, and nerves over time.
For many years, doctors have usually started treatment with a drug called metformin. Metformin is considered the standard first treatment because it is affordable, effective, and generally safe for most people.
However, many patients eventually need a second medication because metformin alone is no longer enough to control their blood sugar. Some people also cannot take metformin because of side effects or other medical problems.
Now, a new study from Northwestern University suggests that two commonly used second-line diabetes drugs may increase the risk of serious heart problems. The findings are raising concerns because these medications are still widely prescribed to millions of people.
The researchers studied six popular second-line diabetes treatments to see how they affected heart health in real-life patients. The study included more than 132,000 adults with type 2 diabetes who had started taking one of these medications after metformin treatment.
The results were worrying. Around 60% of the patients were taking either sulfonylureas or basal insulin. These two older medications were linked to a much higher risk of serious cardiovascular problems, including heart attacks, strokes, heart failure, and even amputations.
The researchers compared these drugs to DPP-4 inhibitors, which are newer diabetes medications. They found that people taking sulfonylureas had a 36% higher risk of major heart-related problems. The risk was even greater for people taking basal insulin, whose risk was about twice as high.
The numbers become even more concerning when translated into real-world impact. According to the study, for every 37 people taking basal insulin over a two-year period, one person would likely experience a serious cardiovascular event. For sulfonylureas, one out of every 103 people would face a similar problem.
This is especially important because diabetes itself already increases the risk of heart disease. People with diabetes are much more likely to suffer from heart attacks and strokes than people without the condition.
If some diabetes treatments further increase those risks, doctors may need to rethink which medicines should be used most often.
The study was led by Dr. Matthew O’Brien, who believes the findings support a major shift in diabetes care. He and his team suggest that doctors should consider using newer medications more often after metformin treatment.
These newer drugs include GLP-1 receptor agonists, such as liraglutide, SGLT-2 inhibitors like empagliflozin, and DPP-4 inhibitors such as sitagliptin. Previous research has suggested that these medications may not only help control blood sugar but also protect the heart in some patients.
GLP-1 drugs work by helping the body release insulin more effectively and reducing appetite. SGLT-2 inhibitors help the kidneys remove extra sugar through urine.
DPP-4 inhibitors improve the body’s natural ability to lower blood sugar after meals. Because these drugs work differently from older treatments, they may have fewer harmful effects on the heart.
However, there is a major challenge. The newer drugs are often much more expensive than older medications like sulfonylureas.
Many patients continue using older drugs simply because they are cheaper and more widely covered by insurance. For people without strong health insurance, cost can strongly influence treatment decisions.
This creates a difficult situation for both doctors and patients. A medication may lower blood sugar effectively but still increase the chance of serious long-term health problems. Doctors must balance affordability with safety, especially for patients who already have a high risk of heart disease.
One important strength of the new study is that it used real-world evidence instead of only relying on tightly controlled clinical trials.
The researchers examined actual medical records and patient outcomes from everyday healthcare settings. This approach gives scientists a clearer picture of what happens in normal life outside laboratory conditions.
The findings were published in the medical journal JAMA Network Open. The study adds to growing evidence that diabetes treatment should focus on more than simply lowering blood sugar numbers. Long-term health outcomes, especially heart health, may be just as important.
The researchers hope the findings will encourage doctors, healthcare systems, and policymakers to think carefully about which diabetes treatments should be recommended most often. They also believe that making safer medications more affordable could improve health outcomes for millions of people.
For patients, the study is an important reminder not to stop or change medications without talking to a doctor. Diabetes treatment is highly personal, and the best medication depends on many factors, including age, overall health, heart disease risk, and cost.
Still, the research offers an important warning. Medicines that have been commonly used for years may not always be the safest choice in the long run. As scientists continue learning more about diabetes and heart disease, treatment approaches may continue to change to better protect patients’ overall health.
For more information about health, please see recent studies that Vitamin D deficiency can increase heart disease risk, and results showing Zinc and vitamin B6 linked to lower death risk in heart disease.
For more information about heart health, please see recent studies about more coffee linked to heart rhythm disease, and results showing Zinc and vitamin B6 linked to lower death risk in heart disease.
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