UCalgary researchers show brain shunts significantly benefit older adults with hydrocephalus

When Jill Knaus shuffled into the Adult Hydrocephalus Program she was hoping to find answers to her health concerns. She suddenly required the use of a cane or a walker. Her gait and balance were off, way off. Life wasn’t the same. 

“I wasn’t walking anymore, not properly. I wore through five pair of shoes because my feet were dragging when I tried to step,” says Knaus. “I couldn’t go for daily walks with my dog, Lucy.”

Knaus chose to move into an assisted living facility. A move she thought was way too soon, but she was worried about falling. She wanted the security of knowing someone could come and help her if she needed it. 

Use of shunts in treatment produces significant improvements 

Dr. Mark Hamilton, MD, Director of the Calgary Adult Hydrocephalus Program at the Cumming School of Medicine, says Knaus’ experience is like that of many people who are living with undiagnosed, and untreated idiopathic Normal Pressure Hydrocephalus (iNPH). A debilitating brain condition that can cause gait and balance disturbances, cognitive decline, and loss of bladder control. The condition results from a buildup of cerebrospinal fluid (CSF) in the brain’s ventricles. Unlike other forms of hydrocephalus, which may be caused by trauma or bleeding, iNPH has no known cause.

It is estimated that 1.5 per cent of people in their late 60s and 7.7 per cent in their mid-eighties are affected. That means one in 13 people at age 86 likely has iNPH. If untreated, iNPH can lead to falls and loss of independence, with eventual severe neurological disability and early death.

A groundbreaking double-blind, placebo-controlled trial - A Randomized Trial of Shunting for Idiopathic Normal-Pressure Hydrocephalus - published in the New England Journal of Medicine, demonstrates that surgical treatment with a shunt (a small tube used to divert CSF from the brain) produced significant improvements in walking speed and balance after just three months. The benefit to those in the group where the shunt was activated and functioning was so improved that the trial was halted early due to its efficacy. 

"Completing this randomized clinical trial was necessary because many neurologists and neurosurgeons were unsure if shunts could effectively treat iNPH, which greatly affected patient access to diagnosis and care,” says Hamilton, neurosurgeon at the Foothills Medical Centre and one of three principal investigators on the paper. “Now, there is no doubt. Shunt surgery for iNPH has been confirmed to improve walking and balance, decrease falls, and restore independence. Shunt surgery for iNPH is both safe and effective."

The study was conducted at 17 sites in Canada, the U.S., and Sweden. 

Diagnosis and surgery gives hydrocephalus patient their life back

Eighty percent of the 49 participants in the open valve group showed significant and meaningful clinical improvement in walking speed and balance. Other cognitive function assessments also improved. The 50 participants in the placebo group experienced minimal or no improvement in their gait velocity or other outcomes. 

Knaus says the diagnosis and surgery done in 2024 have changed her life for the better.

“I’m walking my dog again up to four-times a day without the use of a cane or walker. I’ve lost 20 pounds,” says the 79-year old Knaus. “I feel much younger, and happier. I’ve got my life back.”

The study was supported by the National Institutes of Health.