Cardiovascular Risks of Common Second-Line Type 2 Diabetes Drugs
A large recent study has raised important safety questions about two widely used drug classes for type 2 diabetes—sulfonylureas and basal insulin. Both are commonly prescribed after metformin when blood sugar remains uncontrolled, but they appear to carry higher risks of serious cardiovascular problems compared with several newer diabetes treatments.
Key Points at a Glance
- Sulfonylureas and basal insulin, two standard second-line therapies for type 2 diabetes, are associated with a higher risk of cardiovascular events.
- These drugs are often prescribed after metformin when additional blood sugar control is needed.
- Newer medication classes—including DPP-4 inhibitors, GLP-1 receptor agonists, and SGLT-2 inhibitors—generally show more favorable cardiovascular profiles.
- Clinicians are encouraged to factor in these cardiovascular risks when choosing diabetes therapies, especially for patients with existing heart disease or risk factors.
What the Study Found
The research, published in JAMA Network Open, evaluated health data from more than 130,000 adults with type 2 diabetes who were starting a second-line diabetes medication after metformin.
The analysis revealed:
- Patients treated with sulfonylureas had about a 36% higher risk of major cardiovascular events.
- Those started on basal insulin faced approximately double the risk of such events.
These cardiovascular events included:
- Heart attack
- Stroke
- Hospitalization for heart failure
- Amputation
Because sulfonylureas and basal insulin are prescribed so frequently, the impact at the population level could be substantial. Some estimates indicate that up to 60% of patients who need a second-line drug receive one of these two options.
The study further suggested:
- For sulfonylureas, about 1 in 103 patients treated over a two-year period may experience a cardiovascular event related to the drug.
- For basal insulin, the estimated risk increases to 1 in 37 patients over two years.
These numbers highlight why the findings are prompting serious discussion among healthcare providers.
Newer Drugs and Cardiovascular Safety
The study compared sulfonylureas and basal insulin with several newer classes of diabetes medications:
- DPP-4 inhibitors
- GLP-1 receptor agonists
- SGLT-2 inhibitors
DPP-4 inhibitors are generally considered cardiovascularly neutral, meaning they do not significantly increase or decrease cardiovascular risk. When newer drug classes were evaluated against DPP-4 inhibitors, they:
- Did not show an increased risk of cardiovascular harm.
- Often demonstrated similar or better cardiovascular safety profiles compared with sulfonylureas and basal insulin.
Although these newer medications can be more expensive, many experts believe they may be a safer option for blood sugar control in patients who also have, or are at high risk for, heart disease.
A Call for a Shift in Treatment Strategy
Lead author Dr. Matthew O’Brien and his colleagues argue that these findings should prompt a “paradigm shift” in how type 2 diabetes is treated, particularly beyond metformin.
Key implications include:
-
Early consideration of cardiovascular risk
When choosing add-on therapy after metformin, clinicians should weigh not only blood sugar–lowering effectiveness, but also the long-term impact on heart and vascular health. -
Re-evaluating the routine use of sulfonylureas and basal insulin
While these drugs have been mainstays of treatment for decades, their potential to increase cardiovascular events suggests they may not be the best second-line choice for many patients. -
Understanding differences between study types
The authors note that, in real-world observational data, newer drugs may not always show the same level of cardiovascular benefit seen in randomized clinical trials of patients with established cardiovascular disease. However, the key message is that they do not appear to carry the same level of cardiovascular risk as sulfonylureas and basal insulin.
What This Means for Patients and Providers
This research reinforces the importance of individualized treatment plans in type 2 diabetes care.
For Patients
- Long-standing medications such as glipizide (a sulfonylurea) and similar drugs have been effective at lowering blood glucose for many years, but:
- They may come with higher risks to the heart and blood vessels.
- These risks are especially relevant if you already have heart disease, high blood pressure, high cholesterol, or other cardiovascular risk factors.
- Patients should not stop their medications on their own, but are encouraged to:
- Talk with their healthcare provider about all available treatment options.
- Ask whether a newer drug class (DPP-4 inhibitor, GLP-1 receptor agonist, or SGLT-2 inhibitor) might be a safer alternative.
- Discuss cost, side effects, and insurance coverage, since newer agents can be more expensive.
For Healthcare Providers
- When intensifying therapy beyond metformin, consider:
- The cardiovascular risk profile of sulfonylureas and basal insulin.
- The neutral or favorable cardiovascular characteristics of DPP-4 inhibitors, GLP-1 receptor agonists, and SGLT-2 inhibitors.
- For patients with existing cardiovascular disease or multiple risk factors, prioritizing medications with proven or neutral cardiovascular effects may be especially important.
- Regularly reassess treatment regimens as new safety and effectiveness data emerge.
Sources
- “Common diabetes drug linked to heart disease: This is what the study says,” Times of India
- “Two Type 2 Diabetes Drugs Linked to Higher Risk of Heart Disease,” Northwestern University
- “Common diabetes drugs linked to higher heart disease risk,” AJC.com
- “Common Diabetes Drugs Linked to Higher Risk of Heart Attack and Stroke,” Diabetes In Control
- “Two common diabetes drugs linked to heart attack, stroke risk,” UPI.com
