When It's Not Alzheimer’s: Little-Known Illness Mimics Dementia

Aug 14, 2013

The last thing most patients do when they receive an Alzheimer’s diagnosis is seek another diagnosis.

But research shows that up to 5 percent of dementia cases are misdiagnosed cases of a treatable but largely unknown condition called “normal pressure hydrocephalus.”

It is theorized that NPH arises from excess fluid building up in the brain. The cure is to drain the fluid with shunts.

In one case described in The Boston Globe, a Massachusetts man named Jim Lampert was confined to a nursing home, unable to control his bladder or bowels, read or even carry on a conversation.

Though diagnosed with Alzheimer’s, his wife was skeptical, and finally had her husband re-diagnosed and treated.

Dr. Mark Johnson runs the Adult Hydrocephalus Program at Brigham and Women’s Hospital in Boston and cared for Lampert.

After Johnson surgically inserted a shunt system into his brain to drain the excess fluid, Lampert got his mobility and his life back.

Johnson has treated a number of patients for NPH, but he is still awed by the outcome of the treatment.

“I still feel that way whenever I see this transformation in patients, after the shunt has been placed,” Johnson said. “And it’s a godsend for the patients and for their caregivers.”


  • Dr. Mark Johnson, brain surgeon and head of the Adult Hydrocephalus Program at Brigham and Women’s Hospital.
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If you have a loved one diagnosed with Alzheimer's, have you sought out a second opinion? Maybe not. The symptoms are so compelling - loss of memory, inability to speak or read, walking funny. But wait. Those are also some of the symptoms of a treatable, even curable illness called normal pressure hydrocephalus.

The Boston Globe recently profiled 72-year-old Jim Lambert, whose health severely declined over two years until he was eventually put in a nursing home or, as he says now, "they put me in a cupboard and forgot about me" - except for his wife, who never believed Jim had Alzheimer's.

And she finally found our next guest, who proved her right. Brain surgeon Mark Johnson heads the Adult Hydrocephalus Program at Brigham and Women's Hospital here in Boston. Doctor, welcome.

DR. MARK JOHNSON: Thank you. Thank you for having me.

YOUNG: So a misdiagnosis. How often does this happen that someone is diagnosed with Alzheimer's and they actually have this treatable illness?

JOHNSON: Well, current estimates are that 5 to 10 percent of patients with dementia actually have NPH; and most of those patients who have dementia are diagnosed with Alzheimer's or Parkinson's disease, or they have no diagnosis at all.

YOUNG: But they have this - as you say - NPH, normal pressure hydrocephalus. What is it?

JOHNSON: So it's thought to be caused by an excess of fluid in the brain, although there's some debate about whether that's really the problem. It's certainly the case that if you look at a CT scan of the brain or an MRI of the brain, these patients often have more fluid than normal. And if you drain that fluid, they get better.

YOUNG: Well, then that is the treatment. You put a shunt in and you literally drain it. And what happens? What do you see happen?

JOHNSON: So often these patients will come in with many months or even many years of walking problems. They often have incontinence. They may wet themselves, wet the bed at night. And often they have dementia, usually short-term memory problems. And after draining the fluid, the walking will improve. I've had many patients who've come in a wheelchair, unable to walk, and then after placement of the shunt, they're able to walk without assistance. The incontinence will often go away completely, and their memory will improve.

YOUNG: Well, one person who came to you was Florida philanthropist Susan Sontag, not to be confused with the author. She'd fought brain cancer, started a foundation, was having new health problems when she was coincidentally sitting next to you at a dinner, and you determined what?

JOHNSON: Right. Well, I have known the Sontags for quite some time. When I first established a brain tumor research laboratory at the Brigham and Women's Hospital, they supported my research. So I have known them, and have attended their scientific foundation meetings annually, for about 10 years. And over that time, I had observed her walking ability decline, and had also spoken with her and her husband about some memory issues that she was having.

And recently, the penny dropped in my own mind and I thought, you know, she looks like a person with normal pressure hydrocephalus. And I suggested that she be evaluated. Until that point, everyone had thought that this was simply the side-effects of her brain tumor treatment.

YOUNG: And that would be a reasonable conclusion because she did successfully fight brain cancer - but one would think, well, maybe this is an after-effect of that. And in the case of Jim Lambert - we mentioned him, the 72-year-old who was profiled by The Globe - it was discovered he had normal pressure hydrocephalus after he was so declined that he was in a nursing home, slumped in a wheelchair. What happened to both him and Susan Sontag when they had the shunts put in, to drain the fluid from their brains?

JOHNSON: That's right. So when I met Mr. Lambert, he was in a wheelchair. He could not stand on his own, required two people to assist him; and had been told that he had Alzheimer's disease. But in his case and in Susan Sontag's case, we placed a shunt, and their walking improved tremendously. Ms. Sontag was able to walk, but she was very unstable and required assistance, especially on uneven ground. And she, after the shunt was placed, was able to walk briskly down the hallway without any assistance.

YOUNG: It would seem miraculous to the family members, I would guess.

JOHNSON: You know, we all felt that way, too, and I still feel that way whenever I see this transformation in patients after the shunt has been placed. And it's a godsend for the patients and for their caregivers. It really makes a big difference.

YOUNG: Well, Jim Lambert is now back at home. His wife can care for him. He's moving around except for, you know, on occasion, he might need a cane. I mean, just quite something, home from the nursing home. We don't want to get people's hopes up, Dr. Johnson, but would you recommend that people who have received the diagnosis of Alzheimer's, that their family members check out normal pressure hydrocephalus?

JOHNSON: I think patients who have been diagnosed with Alzheimer's or Parkinson's disease, or any patients who have one or more of these symptoms that develop as they get older, should be evaluated. So the symptoms are problems walking.

YOUNG: Actually, that jumped out at us because it's problems walking, but also a pretty specific - like, a wide stance, shuffling gait.

JOHNSON: Yeah. They have something we sometimes call the magnetic gait. It's as if their feet are stuck to the floor. So they usually shuffle along. But I have seen some patients who just complain of being off-balance. So that's a major symptom of normal pressure hydrocephalus. Incontinence is another one and, as I mentioned, some memory difficulties. And some patients have one or two of these symptoms. You don't have to have all three. But if you find that you're developing these symptoms as you get older, I do think it's worth being screened to see whether it's NPH because that can be treated.

YOUNG: Quite something. Dr. Mark Johnson, who heads the hydrocephalus center at Brigham and Women's Hospital here in Boston. Dr. Johnson, are doctors aware of this across the country? It sounds like they will be more aware now. This is getting some publicity but I'm wondering, will doctors be aware?

JOHNSON: So there was a recent study - in 2008, which showed that somewhere between 10 and 30 percent of doctors have never actually heard of normal pressure hydrocephalus. So I do think it's important for doctors to learn more about this disorder, and for patients to raise these questions with their doctors.

YOUNG: Dr. Johnson, thanks so much.

JOHNSON: Thank you so much.

YOUNG: So is this raising alarms? Or maybe you've had this experience, Alzheimer's that was really this normal pressure hydrocephalus. Share that experience, or find more information on NPH at hereandnow.org. Other ways to reach us, by the way: facebook.com/hereandnowradio, on Twitter @hereandnow, @hereandnowrobin, @jeremyhobson. Transcript provided by NPR, Copyright NPR.