A new clinical study has shown that shunting — the diversion of the extra fluid buildup in the brain — restores mobility and results in walking improvements in older adults with a type of hydrocephalus. The findings, published in The New England Journal of Medicine, help resolve decades of debate on whether shunts help patients with this condition.
Poor mobility and frequent falls are common in older adults. These symptoms can sometimes be dismissed as typical signs of aging. However, the imbalance and walking issues may be caused by idiopathic normal pressure hydrocephalus (NPH) — the buildup of cerebrospinal fluid in the brain.
"This landmark trial is the result of a global collaboration among top academic medical centers. It shows with a high level of evidence that for elderly patients with hydrocephalus, shunting can help regain independence and balance," said Kiarash Shahlaie, professor and chair of the UC Davis Department of Neurological Surgery and coauthor on the study. UC Davis Health is one of the research sites for this clinical study.
Avoiding a missed diagnosis
Frequent falls and walking issues due to untreated NPH could result in the loss of independence, nursing home placement and higher mortality risk. Surgical implantation of a shunt is the only effective treatment to manage cerebrospinal fluid drainage.
Despite its potential for treatment, this condition is often overlooked as a diagnosis. Only 1 in 5 patients who could benefit from a shunt surgery for NPH are referred for evaluation.
"Diagnosis boils down to a clinical suspicion. Progressive walking difficulty, cognitive problems and urinary issues are some of the telltale signs of normal pressure hydrocephalus. Yet, it has long been underrecognized, leaving many older adults struggling with a preventable disability," said UC Davis neurosurgeon Branden Cord. Cord did the surgeries to implant the shunts in the participants enrolled at UC Davis Health.
Timely diagnosis and proper treatment can mean a better quality of life for patients.
About the study
The trial enrolled 99 patients across 17 centers in the U.S., Canada and Sweden. All participants had surgery and received a programmable shunt.
In half of the participants, the shunt worked as a placebo that was set not to function during the trial. In the other half, the shunt setting was open, allowing it to work. Neither the patients nor their doctors knew which group they were in.
The study examined walking speed in both groups.
After three months, participants in the open-shunt group walked significantly faster than before surgery. In the placebo group, gait speed stayed the same.
Patients in the open-shunt group also had improved balance and reported fewer falls. In the open-shunt group, 25% of patients reported falling during the trial, compared with 46% of those in the placebo group.
"For patients and families, the most powerful outcome of this trial is hope," Cord said. "We are deeply grateful for the commitment of the patients who generously volunteered to participate in this trial. At UC Davis, we are proud to contribute to research that advances neurosurgical science and changes lives in very tangible ways."
The Placebo-Controlled Effectiveness in iNPH Shunting (PENS) Trial was led by researchers at Johns Hopkins University. It was funded by the National Institutes of Health and the National Institute of Neurological Disorders and Stroke.
