Shunts Safe And Effective For Rare Brain Condition In Elderly, Clinical Trial Concludes

A simple shunt can restore walking ability and independence in elderly people with a rare brain condition, a major new clinical trial has found.

Implanting a shunt to drain excess cerebrospinal fluid significantly improved walking and mobility among seniors with idiopathic normal pressure hydrocephalus (NPH), researchers reported Sept. 16 in The New England Journal of Medicine.

The condition is caused by a buildup of fluid in between the brain and spine and a person’s skull, researchers said. Left untreated, it leads to walking and balance problems, memory decline and bladder control issues.

Doctors have known about normal pressure hydrocephalus since 1965, and for decades have been using surgically implanted shunts to relieve pressure on patients’ brains. Shunts are thin, surgically implanted tubes that allow excess fluid to drain off.

However, there’s been ongoing debate regarding the use of shunts, and even the existence of NPH, researchers said.

“If there’s one thing this study does, it resolves a controversy that’s been around for many, many years,” said co-lead researcher Dr. Michael Willams, a professor of neurology and neurological surgery at the University of Washington School of Medicine in Seattle. “There’ve been a lot of physicians who doubt that the disorder exists or that treatment with the surgical implantation of a shunt is either effective or safe.”

This trial puts that to rest, he said in a news release.

“Our hope is that now, more neurologists, more neurosurgeons, more doctors will entertain the possibility of (NPH) as a diagnosis for their patients, take them through appropriate diagnostic steps and treat them when hydrocephalus is found,” Williams said.

Idiopathic normal pressure hydrocephalus affects about 1.5% of people in their late 60s, and up to nearly 8% of those in their 80s, researchers said in background notes. Idiopathic means the cause for the pressure increase is unknown.

Researchers estimate that as many as 20% of patients who could benefit from a shunt are referred for evaluation, because their symptoms are dismissed as normal signs of aging.

Symptoms become more severe and death more likely the longer the condition remains untreated, researchers said.

For the new trial, researchers enrolled 99 patients at 17 hospitals in the U.S., Canada and Sweden.

All the patients received a functioning shunt, but in half chosen at random the shunt was adjusted so that it didn’t drain away fluid, creating a placebo condition.

The shunt used in the study could be turned on or off and the flow adjusted using a magnetic device, researchers said. Neither the patients nor the doctors treating them knew whether they’d been chosen to have an active shunt.

After three months, patients with active shunts walked significantly faster than they did before surgery, while the group with non-active shunts showed no change.

In fact, walking speed in the shunt group improved by more than double the threshold considered to be clinically meaningful, researchers said.

In all, 80% of patients with active shunts achieved meaningful improvement in walking and mobility, compared to 24% of those in the placebo group.

About 25% of patients with an active shunt reported a fall during the trial, compared with 46% of those with a non-working shunt, results showed.

“When a person walks better and doesn’t fall, everything improves: their independence, their safety and their quality of life,” co-lead researcher Dr. Mark Luciano, director of the Johns Hopkins Hydrocephalus and Cerebral Fluid Center in Baltimore, said in a news release.

Results also showed improvement in cognitive function and bladder control, but those benefits were not statistically significant.

Identifying seniors with normal pressure hydrocephalus who might benefit from a shunt can be simple, Luciano said.

“If there appears to be imbalance that’s increasing, or memory loss that’s increasing, it’s a diagnosis that can be explored with a routine brain scan,” he said.

At the end of the trial’s first phase, all of the placebo patients’ shunts were turned on so they could potentially receive the same benefits, researchers said.

Researchers will continue to follow the clinical trial’s participants to measure long-term outcomes and see if they achieve gains beyond walking and mobility.

“It has always been suspected that cognitive changes take longer to improve and need more detailed testing,” Luciano said. “At the 12-month period, we’ll have more to say not only about cognition, but how much patients are improving in their activities and independence.”

But Williams suspects that shunt treatment for normal pressure hydrocephalus might be embraced by the medical community based on these results alone.

“If our study has influence, we should see an increase in the number of people who are being found to have iNPH and who are getting treated,” Williams said. “That’s going to be a lot of improvement for the elderly population.”

Researchers also presented their findings this week at the annual meeting of the American Neurological Society in Baltimore.

More information

The Cleveland Clinic has more on normal pressure hydrocephalus.

SOURCES: Johns Hopkins Medicine, news release, Sept. 16, 2025; American Neurological Association, news release, Sept. 16, 2025; New England Journal of Medicine, Sept. 16, 2025

Source: HealthDay