Managing high blood pressure is one of the most important ways to slow kidney damage in people with type 2 diabetes. However, new research is raising questions about whether one commonly used class of blood pressure medications may not be the best choice for every patient.
Researchers reported that people with type 2 diabetes who were taking dihydropyridine calcium-channel blockers (DCCBs) had a higher risk of serious kidney complications compared with patients receiving other blood pressure treatments. The findings were presented at the 63rd European Renal Association Congress and have not yet undergone peer review.
While the results are attracting attention, specialists emphasize that the study shows an association rather than proof of cause and effect.
Why Blood Pressure Control Matters in Diabetes
Type 2 diabetes is a leading cause of chronic kidney disease. Persistently elevated blood sugar can damage the small blood vessels responsible for filtering waste from the bloodstream.
When high blood pressure is present at the same time, kidney damage often progresses more rapidly.
For this reason, treatment plans commonly include medications that lower blood pressure while also helping protect kidney function.
Current standard therapy frequently includes:
- Renin-angiotensin system inhibitors (RAS inhibitors), which help reduce pressure within the kidneys and slow disease progression.
- SGLT2 inhibitors, which lower blood sugar and provide additional protection for the kidneys and cardiovascular system.
Despite these therapies, many patients still require additional medications to achieve recommended blood pressure targets. DCCBs are among the most frequently prescribed options for this purpose.
Examining Real-World Outcomes
Researchers analyzed health data from 31,041 adults with type 2 diabetes treated between 2016 and 2021.
All participants were receiving both RAS inhibitors and SGLT2 inhibitors and required an additional blood pressure medication.
Among them:
- 11,841 patients (38.1%) were taking a DCCB.
- 19,200 patients (61.9%) were receiving another type of blood pressure medication.
Participants were followed for a median of 3.5 years.
During the study period:
- 482 patients experienced a major adverse kidney event.
- 2,066 patients died from various causes.
Higher Risk of Kidney Complications
After analyzing the data, researchers found that DCCB use was associated with a 33% higher risk of major adverse kidney events compared with alternative blood pressure treatments.
The findings contrast with some earlier research that suggested DCCBs might help reduce the risk of advanced kidney disease.
The new results therefore raise important questions about whether these medications remain the optimal choice for people already receiving modern kidney-protective therapies.
Researchers noted that most deaths observed during the study were related to cardiovascular disease or infections rather than kidney failure itself.
Why the Findings Need Confirmation
Experts caution against drawing immediate conclusions.
Because the study was observational, researchers cannot determine whether the medications themselves caused the increased risk. Patients prescribed DCCBs may differ from those receiving other treatments in ways that are difficult to fully account for in statistical analyses.
Residual confounding, treatment-selection bias, and other factors could have influenced the results.
As a result, specialists say larger studies — ideally prospective clinical trials — are needed before treatment guidelines should be reconsidered.
What Patients Should Do
Researchers stress that people currently taking DCCBs should not stop or change their medication without consulting their healthcare provider.
Blood pressure control remains one of the most effective ways to slow diabetic kidney disease and reduce the risk of heart attack, stroke, and kidney failure.
Treatment decisions should be individualized based on a patient’s overall health, kidney function, cardiovascular risk, and response to therapy.
Reducing Blood Pressure in Type 2 Diabetes
In addition to medication, lifestyle measures remain a cornerstone of treatment.
Strategies that can help lower blood pressure include:
- Maintaining a healthy weight
- Following a diet rich in fruits and vegetables
- Reducing sodium intake
- Increasing physical activity
- Limiting alcohol consumption
- Avoiding tobacco use
For patients who require additional medication beyond RAS inhibitors and SGLT2 inhibitors, clinicians have several options available. One alternative mentioned by researchers is thiazide diuretics, which are commonly used and generally considered effective, though they may require monitoring of kidney function and electrolyte levels.
What Comes Next?
Researchers are planning additional studies to determine whether the association seen in this analysis can be confirmed in other populations, including people without diabetes.
For now, the findings highlight the complexity of treating diabetic kidney disease and underscore the importance of continually evaluating whether established therapies remain the best option as new evidence emerges.
