Normal Pressure Hydrocephalus (NPH): The Reversible Form of Dementia You Need to Know
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Quick Answer: 5 Essential Facts About NPH
Normal pressure hydrocephalus (NPH) is a buildup of cerebrospinal fluid that presses on brain tissue while pressure inside the skull stays normal. [1] It causes walking problems, urinary incontinence and cognitive difficulties, mostly in adults over 65. [1] The main treatment is surgery to implant a shunt that drains the fluid, and it is often treatable and sometimes reversible with early care. [1]
Feature | Details |
Primary cause | A buildup of cerebrospinal fluid (CSF) that presses on brain tissue while pressure inside the skull stays in the normal range. [1] |
Key symptoms | Hakim's triad: walking (gait) problems, urinary incontinence, and cognitive difficulties. [1] |
Typical patient | Most common in adults over 65. The average age of onset is around 70. [1] |
Main treatment | Surgery to implant a shunt that drains the extra fluid. [1] |
Outlook | Often treatable and sometimes reversible. The best results come with early diagnosis and treatment. [1] |
What the research says
Shunt surgery probably improves walking in the short term. A Cochrane review of 4 randomized trials (140 people, average age 75) found that CSF shunting probably improves gait speed within six months (standardized mean difference 0.62, 95% CI 0.24 to 0.99) and probably reduces disability (risk ratio 2.08, 95% CI 1.31 to 3.31). The effect on thinking and memory was very uncertain, and there were no longer-term trial data. (Pearce et al., Cochrane Database Syst Rev, 2024) [2]
Most people improve after surgery, but not everyone, and complications are common. A pooled analysis of 54 studies and 4,811 people with idiopathic NPH found that more than 74% improved after CSF diversion surgery (95% CI 70% to 78%). Gait improved in 72%, while bladder control and thinking each improved in about 50%. Complications occurred in 20.6% of cases, and 15.1% needed revision surgery. (Salih et al., EClinicalMedicine, 2024) [3]
NPH is likely underdiagnosed. A systematic review of 21 studies found a pooled prevalence of 1.3% in people older than 65 in studies designed to detect NPH, almost 50 times higher than estimates from door-to-door surveys of dementia or parkinsonism. The authors concluded that idiopathic NPH appears to be extremely underdiagnosed. (Martín-Láez et al., World Neurosurg, 2015) [4]
What Is Normal Pressure Hydrocephalus (NPH)?
Normal pressure hydrocephalus (NPH) happens when fluid builds up inside or around the brain and disrupts how it works. That can affect thinking and concentration, memory, movement, and more. [1] The symptoms look very much like those of dementia, but NPH is sometimes reversible. [1]
Cerebrospinal fluid (CSF) is a clear fluid that surrounds the brain and spinal cord. It brings nutrients, carries away waste, and cushions the brain. [1] Adults have only about 150 milliliters (5 fluid ounces) of it [1], and the body constantly makes, circulates, and reabsorbs it to keep that amount steady. [1] In NPH, this balance is disrupted. Fluid builds up slowly, and the fluid-filled spaces in the brain (the ventricles) enlarge and press on the tissue around them.
The term "normal pressure" is used because the pressure inside the skull rises slowly and usually stays within the normal range. [1] Even so, if the fluid keeps building up, the brain starts to compress. If that compression goes on too long, it can permanently damage or destroy brain tissue. [1]
What are the three main symptoms of normal pressure hydrocephalus (NPH)?
NPH symptoms usually start gradually and get worse over three to six months. [1] The three main symptoms are known as Hakim's triad. Between 50% and 75% of people with NPH have all three at the same time. [1]
1. Gait and Movement Issues
Walking problems are the most common of the three, affecting about 80% to 95% of people with NPH. [1] A hallmark is "magnetic feet," the feeling that your feet are stuck to the floor. [1] Steps become shorter, unsteady, and shuffling, which makes tripping and falling more likely. [1] People may freeze when starting to walk, hesitate on turns, turn their toes outward, and walk with feet wide apart. [1] Unlike Parkinson's disease, NPH symptoms typically affect only the legs and feet. [1]
2. Urinary Incontinence
The second part of the triad is loss of bladder control. Early on, it often shows up as needing to pee often or having an unusually strong urge that is hard to control. [1] Later, urine may leak unintentionally. Some people do not seem to notice or feel embarrassed by accidents, which may be linked to the thinking changes of NPH. [1]
3. Cognitive Difficulties
The third symptom type is a change in thinking that can resemble dementia. It can include mental and physical slowness, forgetfulness, trouble with focus, planning, and decision-making (executive dysfunction), and emotional changes such as apathy or losing interest in things you used to enjoy. [1]
What causes normal pressure hydrocephalus, and who is at risk?
Normal pressure hydrocephalus has two distinct forms, and they happen at about equal rates. [1]
Type | Cause and characteristics |
Primary (idiopathic) NPH | The cause is unknown. Experts suspect age-related problems with how the body makes, circulates, or reabsorbs CSF. About half of NPH cases are idiopathic. [1] |
Secondary NPH | Caused by another medical event that affects CSF, such as a brain aneurysm, bleeding in or around the brain, a brain tumor, an infection like meningitis or encephalitis, a stroke, or a traumatic brain injury. [1] |
Increasing age is the only factor that makes NPH more likely, and the odds do not change by ethnicity, race, or sex. [1] NPH is very rare under age 65, affecting about 0.003% of people in that age group. It affects about 0.2% of people between 70 and 80 and about 5.9% of people over 80, according to Cleveland Clinic. [1] NPH can also happen alongside other brain conditions. About 30% of people with NPH also have Alzheimer's disease or a similar degenerative brain condition. [1]
How is normal pressure hydrocephalus diagnosed?
NPH is often hard to diagnose because it shares symptoms with dementia and other age-related conditions, and it commonly happens at the same time as they do. [1] Because the thinking changes can make it hard to notice symptoms in yourself, family and friends may be the ones who notice them. [1]
A healthcare professional uses a mix of a physical and neurological exam, questions about your symptoms and history, and imaging. An MRI scan is the most important tool, since it shows the brain and the areas of fluid buildup. [1] A CT scan can help rule out other conditions but is not usually helpful for diagnosing NPH. [1] A spinal tap (lumbar puncture) cannot diagnose NPH by itself, but it can help rule out other conditions. [1] Removing extra CSF during a spinal tap may temporarily ease symptoms, and symptoms that improve this way make a good outcome more likely. [1]
How is normal pressure hydrocephalus treated, and what is surgical recovery like?
NPH usually does not respond to medicines, although medicines may treat some related symptoms. [1] The most common and most effective treatment for idiopathic NPH is surgery to implant a shunt. [1] A shunt is a drainage system made of two thin tubes (catheters) with a valve between them. When there is too much fluid in the brain, it flows into the inflow catheter, through the valve, and out through the outflow catheter. The outflow tube runs under the skin and most often drains into the abdomen, where the body absorbs the fluid. It can also drain into the chest. [1]
Some modern valves are programmable, so your healthcare team can adjust the settings without another surgery, and some are MRI-safe. [1] Secondary NPH may be curable if the underlying cause can be treated. [1]
Shunt surgery is major surgery. Possible complications include infection, shunt malfunction or failure, shifts in the position of the valve or tubes, and too much fluid draining, which causes low CSF pressure. [1] Most people notice improvement within hours or days, and chances are better when diagnosis and treatment come sooner. Most people also need several days or weeks to recover from the operation. [1] According to Cleveland Clinic, with treatment:
These figures are higher than the pooled results of the studies above (72% for gait and about 50% for bladder control and thinking) [3], so results vary from person to person. Your healthcare team can tell you what to expect.
Why does early treatment matter for normal pressure hydrocephalus?
NPH is unusual among dementia-like conditions because it is often reversible. [1] But it does not go away on its own and it keeps getting worse. If it is left untreated, it eventually causes severe, permanent brain damage and makes it harder, and in time impossible, to live independently. It can also contribute to dangerous complications such as falls. [1]
A few things make a good outcome more likely:
A good outcome is less likely with delayed treatment, thinking problems that start early or are severe, or another degenerative brain condition such as Alzheimer's disease. [1]
When should people with an NPH shunt get help fast?
People with a normal pressure hydrocephalus shunt should get urgent care for worsening headaches, fever, chills, neck stiffness or sudden severe pain near the outflow tube. Tell your team right away if symptoms of NPH return, because that can mean a problem with the shunt. [1] Seek urgent medical attention for:
What is the bottom line on normal pressure hydrocephalus?
Normal pressure hydrocephalus offers a rare chance of recovery from dementia-like symptoms. By recognizing the signs of Hakim's triad, especially the sticky, shuffling "magnetic" walk, families and caregivers can push for early evaluation and treatment. If you or a loved one has trouble walking, new bladder control problems, and changes in thinking, don't write them off as normal aging. Ask a healthcare professional to look for NPH.
Noticing walking, bladder, and memory changes in someone you love? Talk to a healthcare professional soon. A neurological exam and an MRI can help find the cause, and early treatment gives the best chance of recovery.
Frequently Asked Questions
Is NPH the same as Alzheimer's disease?
No. Both can cause memory and thinking problems, but NPH is caused by fluid buildup and is often treatable or even reversible. Alzheimer's is a progressive degenerative disease. The two can also happen together: about 30% of people with NPH also have Alzheimer's or a similar condition. [1]
What does "magnetic feet" feel like?
It is the feeling that your feet are stuck to the floor, like magnets resisting when you pull them away from a magnetic surface. It makes it hard to lift your feet and start walking. [1]
Can NPH be treated without surgery?
NPH usually does not respond to medicines, although medicines may help with some related symptoms. [1] Shunt surgery is the most common and most effective treatment for idiopathic NPH. [1] Secondary NPH may be curable if the underlying cause can be treated. [1]
Is NPH surgery risky?
Shunt placement is major surgery. Possible complications include infection, shunt malfunction or failure, shifts in the position of the valve or tubes, and too much fluid draining. [1] Most people need several days or weeks to recover. Your healthcare team can help you weigh the benefits and risks for your situation.
How quickly do symptoms improve after surgery?
Most people show improvement within hours or days, and the odds are better when diagnosis and treatment happen sooner. Recovery from the operation itself usually takes several days or weeks. [1]
Is NPH hereditary?
Cleveland Clinic lists age as the only factor that makes NPH more likely, and it does not describe NPH as inherited. [1] Idiopathic NPH happens for reasons that are not yet known.
Can a regular X-ray diagnose NPH?
No. A regular X-ray cannot show the inside of the brain. An MRI is the most important test for diagnosing NPH, and a CT scan can help rule out other conditions. [1]
Does NPH cause headaches?
Headache is not one of the three main symptoms of NPH. [1] The name "normal pressure" refers to the pressure inside the skull staying in the normal range. After shunt surgery, though, a headache that starts or gets worse when you sit up or stand can be a sign of a shunt problem, so tell your healthcare team right away. [1]
What happens if NPH is left untreated?
NPH does not go away on its own and it keeps getting worse. Over time it can cause severe, permanent brain damage and make it impossible to live independently. [1] It can also lead to dangerous falls. [1]
Can NPH happen in young people?
It is extremely rare under age 65, affecting only about 0.003% of that age group. [1]
How common is NPH?
According to Cleveland Clinic, it affects about 0.2% of people between 70 and 80 and about 5.9% of people over 80. [1] Studies designed to look for it suggest it may be underdiagnosed. [4]
What is a VP shunt?
A ventriculoperitoneal (VP) shunt is a drainage system that moves extra fluid from the brain's ventricles to the abdominal cavity, where the body absorbs it. It has two thin tubes with a valve between them. [1]
Can NPH cause personality or emotional changes?
Yes. People with NPH can seem apathetic or lose interest in things they used to enjoy, and they may have trouble managing emotions and thoughts. [1]
Is urinary incontinence always present in NPH?
Not always. Gait problems are the most common symptom, affecting about 80% to 95% of people. [1] Between 50% and 75% of people with NPH have all three symptoms of Hakim's triad together. [1]
Can NPH be prevented?
Idiopathic NPH cannot be prevented. You can lower the risk of secondary NPH by treating infections promptly, wearing a helmet and other safety gear to avoid head injuries, and managing health conditions like high blood pressure, diabetes, and high cholesterol. [1]
Related Reading
Romberg Test: How It's Done, What It Checks and What Results Mean explains how this quick balance test checks your body's position sense.
References
Cleveland Clinic. Normal Pressure Hydrocephalus (NPH). Cleveland Clinic. Last updated October 30, 2022. https://my.clevelandclinic.org/health/diseases/15849-normal-pressure-hydrocephalus-nph
Pearce RKB, Gontsarova A, Richardson D, et al. Shunting for idiopathic normal pressure hydrocephalus. Cochrane Database Syst Rev. 2024;8(8):CD014923. PMID 39105473. https://doi.org/10.1002/14651858.CD014923.pub2
Salih A, Arif A, Varadpande M, et al. The effectiveness of various CSF diversion surgeries in idiopathic normal pressure hydrocephalus: a systematic review and meta-analysis. EClinicalMedicine. 2024;77:102891. PMID 39539993. https://doi.org/10.1016/j.eclinm.2024.102891
Martín-Láez R, Caballero-Arzapalo H, López-Menéndez LÁ, et al. Epidemiology of Idiopathic Normal Pressure Hydrocephalus: A Systematic Review of the Literature. World Neurosurg. 2015;84(6):2002-9. PMID 26183137. https://doi.org/10.1016/j.wneu.2015.07.005
Medical disclaimer
This article is for general informational purposes only and is not intended as medical advice. Always consult a qualified healthcare professional for diagnosis and treatment of any medical condition. If you are experiencing a medical emergency, contact your local emergency services immediately.
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