The Neurologist Is In

Monthly insights and advice from a stroke specialist, a movement disorder expert, and a neuromuscular physician.

Wednesday, October 26, 2016

Lewy Body Dementia Is Often Unknown and Unrecognized

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BY MELISSA ARMSTRONG, MD, MSC, FAAN

I recently evaluated a patient—I'll call him "John" to protect his privacy—who came to my clinic with his wife. They described three years of memory problems starting around John's 65th birthday, when he retired from his job as an accountant. On any given day he had moments where he was like his "old self" and moments where he was very confused.

Over the last few years, he had slowed down more and had fallen twice in his home, thankfully without getting injured. Six months earlier he started hallucinating, seeing strange children running around his house. He was diagnosed with a urinary tract infection, which was treated at the time, but the hallucinations never went away. A doctor told the couple that John had "dementia" but offered no other explanation.

In their search for a more complete explanation, the couple ended up at my clinic where I took a full history. Based on John's decline in memory and thinking, problems with walking and movement, fluctuating confusion, and hallucinations, I was able to diagnose him with Lewy Body dementia. I also explained that even though Lewy body dementia is the second-most common dementia after Alzheimer's disease dementia it remains poorly recognized. People often experience long delays and many evaluations before they get a diagnosis—and some people are never diagnosed. For example, in 2014, comedian and actor Robin Williams was diagnosed with the disease only after his death.

Important Terminology

Lewy body dementia is an umbrella term that includes two related conditions that can be diagnosed by physicians: dementia with Lewy bodies and Parkinson's disease dementia. These two conditions overlap in terms of symptoms and what is happening in the brain. Both have Lewy bodies, particular protein clumps, in the brain which are seen on autopsy and which give Lewy body dementia its name.

Characteristic Symptoms

Symptoms of dementia with Lewy bodies and Parkinson's disease dementia include difficulties in memory and thinking severe enough to impact day-to-day life, ups and downs in attention and concentration, hallucinations, and physical difficulties such as slowness, stiffness, and trouble walking. In dementia with Lewy bodies, the difficulties with memory and thinking typically start before or at the same time as the movement problems.

In Parkinson's disease dementia, memory and thinking problems often develop many years after the diagnosis of Parkinson's disease.

Lewy body dementia affects more than just movement and thinking. It can affect sleep, behavior, mood, and other aspects of health. The diagnosis is made based on the history, exam, and sometimes other tests (blood tests or brain scans) to make sure there isn't another cause of the problems. Finding the right diagnosis helps patients and families know what to expect.

How LBD Is Treated

Sometimes patients with Lewy body dementia respond particularly well to drugs approved for use in Alzheimer's disease, including donepezil (Aricept), rivastigmine (Exelon), and galantamine (Razadyne). Only rivastigmine is approved by the US Food and Drug Administration (FDA) for people with Lewy body dementia. These medications may improve thinking to a modest extent; in Lewy body dementia, they can ease symptoms like hallucinations, too. In 2016, the FDA approved pimavanserin, an atypical antipsychotic that does not work through dopamine pathways, to treat hallucinations in patients with Parkinson's disease dementia. This medication has not been formally studied in people with dementia with Lewy bodies. It is important for patients with Lewy body dementia to avoid antipsychotic medications that work through dopamine pathways, when possible, as these drugs can cause worsening of some symptoms.

A Push for More Research

More research is needed to understand the brain changes in Lewy body dementia, to improve recognition and diagnosis, and to find treatments.

If you think that you or a loved one may have unrecognized Lewy body dementia, request a consultation with a neurologist, dementia specialist, or movement disorders specialist.

For more information on Lewy body dementia, see "A Different Kind of Dementia" (April/May 2015, bit.ly/NN-DifferentDementia),  "Dementia 101" (December 2015/January 2016, bit.ly/NN-dementia101), or contact the Lewy Body Dementia Association—a patient organization that provides outreach and support for families affected by LBD as well as educational programs and resources—at lbda.org.

Armstrong_Melissa (1).JPGDr. Armstrong is a movement disorders specialist at the University of Florida Health Center for Movement Disorders and Neurorestoration in Gainesville. She is also involved in the American Academy of Neurology's evidence-based guideline program.