Combination of Blood Pressure Drugs May Harm Kidneys
Research shows ACE inhibitors or ARBs may help control kidney disease symptoms, but not when taken together.
Angiotensin-converting-enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are two commonly prescribed medications for blood pressure control. Studies in recent years have also shown that, individually, the drugs can help protect against the worsening of kidney disease symptoms.
However, recent research has also shown that the two medications lose their protective benefits when patients take both of them. And in fact, the combination of an ACE inhibitor and an ARB may contribute to serious health complications.
The NEPHRON-D study, reported in the New England Journal of Medicine, found that the combination of the two drugs may lead to serious adverse effects in patients with diabetic nephropathy. In simplest terms, diabetic neuropathy is kidney damage caused by diabetes.
Nephrologist Joseph Nally, MD, Director of the Chronic Kidney Disease program at Cleveland Clinic, says the NEPHRON-D study and other major trials suggest that it is time to stop prescribing the combination of drugs to patients with kidney disease and diabetes.
The combination of ACE inhibitors and ARBs can contribute to high potassium levels in the bloodstream. One of the main jobs of the kidneys is to control potassium and sodium levels, but blood pressure drugs can lead to an imbalance of the two minerals.
“They’re both renal protective, which is a good thing,” Nally says. “They’re both cardio-protective for patients with heart failure, too, but not together. The NEPHRON-D study results demonstrating no benefits but increased risk with combination therapy asked the question, ‘Is this the end of combination therapy with ACE and ARB?’ The answer is yes.”
Another recent study, conducted by British researchers and published in the journal PLoS ONE, suggests that the use of ARBs and ACE inhibitors may lead to higher hospitalization rates for kidney failure.
How these drugs work
An ACE inhibitor helps relax blood vessels by preventing an enzyme in the body from narrowing the blood vessels and releasing hormones that raise blood pressure. An ARB blocks the action of that same enzyme.
While the drugs may pose a threat to people who take both of them, they can be safe and effective when paired with other anti-hypertensive medications, Dr. Nally explains. “Either an ACE or an ARB plus a diuretic is a good combination,” he says. Thiazide-type diuretics, which help lower blood pressure by reducing sodium and fluid levels in the body, are often first-line treatments for hypertension. But new blood-pressure treatment guidelines suggest that first-line treatments could also include ACE inhibitors, ARBs and calcium channel blockers.
ACE inhibitors tend to be more commonly prescribed because generic versions of these drugs are more widely available than generic ARBs.
Dr. Nally recommends that if you have been prescribed both ACE inhibitors and ARBs, you should talk with your doctor about the risks associated with the combination, and whether an alternative drug could be prescribed.