A new review of medical literature suggests alpha blockers may be useful in patients with large kidney stones. The study was published online Dec. 1 in The BMJ. http://www.bmj.com/content/355/bmj.i6112

A 2015 multicenter study of 1,136 subjects in the U.K. questioned the effectiveness of alpha blockers to facilitate kidney stone passage, and the authors of the new review wanted to put the 2015 study into the context of other kidney stone research.

“If we can facilitate kidney stone passage without surgery, it allows our patients to avoid extra pain and risks that come with a surgical procedure,” says first author John M. Hollingsworth, M.D., associate professor of urology at the University of Michigan Medical School. “When the 2015 study did not show a significant difference between alpha blockers and placebos, we wanted to explore the issue further.”

Pooling the research

Hollingsworth and his pooled a total of 55 randomized controlled trials comparing alpha blockers to placebo or control. They then considered stone size and location in the 5,990 study subjects to see if either one was a factor in successfully passing the stone.

“We found alpha blockers were successful, but the benefit is primarily in patients with larger kidney stones,” said co-author Benjamin K. Canales, MD, associate professor of urology at the University of Florida College of Medicine.

Researchers report a 57% higher risk of stone passage for larger stones with an alpha blocker, but no benefit for smaller stones. Location did not make a difference, nor did type of alpha blocker used.

“It’s important not to discount low-risk options for patients who may benefit from them,” said senior author Philipp Dahm, MD, professor of urology at the University of Minnesota Medical School. “Our findings suggest providers consider prescribing a course of an alpha blocker.”

Because so many different kinds of physicians see kidney stones, the treatment guidelines are especially important, Hollingsworth said.

“There had been a fair amount of ambiguity following the UK trial. However, our findings help solidify surrounding guideline recommendations on alpha blockers in patients with stones,” he said.