Millions of people around the world live with both type 2 diabetes and high blood pressure. These two conditions often occur together and can be especially dangerous because they increase the risk of kidney disease.
Over time, high blood sugar and high blood pressure can damage the kidneys, making it harder for them to remove waste and extra fluid from the body. When kidney disease becomes severe, some patients may eventually need dialysis or a kidney transplant.
Doctors have made major progress in treating diabetic kidney disease in recent years. Several newer medications have helped slow kidney damage and reduce the risk of kidney failure.
However, a new study suggests that one commonly used group of blood pressure medicines may not be as helpful as once believed for some patients with diabetic kidney disease.
The research was presented at the 63rd ERA Congress, one of the leading international meetings focused on kidney health.
Researchers examined whether a class of blood pressure medicines known as dihydropyridine calcium-channel blockers, often called DCCBs, affects kidney health in people with type 2 diabetes who are already receiving modern kidney-protective treatments.
DCCBs are widely prescribed around the world. These medicines help lower blood pressure by relaxing blood vessels and improving blood flow.
They are often added when a person’s blood pressure remains high despite initial treatment. Because controlling blood pressure is one of the most important ways to slow kidney damage, DCCBs have become a common choice for many patients.
To understand their long-term effects, researchers analyzed health information from 31,031 adults with type 2 diabetes between 2016 and 2021. Every participant was already receiving two important types of kidney-protective medicines.
One group of drugs, called RAS inhibitors, helps lower blood pressure and reduce stress inside the kidneys. Another group, called SGLT2 inhibitors, was originally developed to treat diabetes but has become widely recognized for its ability to protect kidney function and reduce the risk of kidney failure.
Among the participants, more than 12,000 people were also taking DCCBs, while nearly 19,000 were using other blood pressure treatments. The researchers followed patients for about three and a half years.
The results raised concerns. Patients taking DCCBs had a 33% higher risk of experiencing major kidney-related problems compared with those taking other blood pressure medicines. These problems included a major decline in kidney function or progression to end-stage kidney disease requiring dialysis or transplantation.
Researchers believe the findings may be linked to how DCCBs affect blood flow inside the kidneys. The kidneys contain millions of tiny filtering units that constantly clean the blood.
In people with diabetic kidney disease, these filtering units are already under stress. The researchers suggest that DCCBs may increase pressure inside these delicate structures, potentially leading to additional damage over time.
One surprising finding was that the increased risk remained even though patients were already taking modern kidney-protective medicines. Scientists had hoped that SGLT2 inhibitors would offset any potential negative effects, but that did not appear to happen.
The study’s lead author, Dr. Timna Agur, noted that DCCBs are commonly prescribed as second-line treatments for blood pressure control in people with diabetic kidney disease. Because of their widespread use, even a modest increase in kidney risk could affect a large number of patients worldwide.
The researchers emphasized that this was an observational study. This means it can identify links between medications and outcomes, but it cannot prove that DCCBs directly caused the worsening kidney disease. Other factors may also have contributed to the results.
Even so, the findings are important because they suggest doctors may need to look more carefully at which blood pressure medicines are best for patients with diabetic kidney disease. Future clinical trials will be needed to confirm whether these medications truly increase kidney risk and whether alternative treatments may provide better protection.
Analysis of the findings suggests the study raises an important clinical question rather than providing a final answer. The large number of participants strengthens the reliability of the results, but observational research cannot establish cause and effect.
Nevertheless, the findings challenge current assumptions about a commonly used medication class and highlight the need for more personalized treatment decisions.
If future studies confirm these results, doctors may reconsider the role of DCCBs in patients with diabetic kidney disease and potentially improve long-term kidney outcomes for millions of people.
If you care about high blood pressure, please read studies that early time-restricted eating could help improve blood pressure, and natural coconut sugar could help reduce blood pressure and artery stiffness.
For more health information, please see recent studies about added sugar in your diet linked to higher blood pressure, and results showing vitamin D could improve blood pressure in people with diabetes.
The findings were presented at the 63rd ERA Congress.
Source: ERA Congress.
