Lewy Body Dementia

This week let’s investigate further into the third most common cause of dementia, Lewy body dementia. In 1912 a German neurologist named Friederich Lewy discovered clumps of an abnormal protein in persons with Parkinson's disease. These clumps of alpha-synuclein protein, now called Lewy bodies, gathered in places in the brain that are important for memory and movement, interfering with neuron (brain cell) function and eventually causing their death.

Overall Lewy body dementia causes up to 10% of all dementias, but is very challenging to diagnose because of the overlap with other causes. Lewy bodies can be found in persons with Alzheimer’s disease and with Parkinson’s disease dementia, so many of the symptoms of Lewy body dementia can be seen in those disorders. The average age of diagnosis is 75, and it much more commonly affects men over women at a 4:1 ratio.

The symptoms of Lewy body dementia are difficult to extricate from other dementias, but there are some “core” features:

• Cognitive fluctuations

• Visual hallucinations

• Rapid eye movement sleep disorder behaviors

• Parkinsonism

To keep it simple, persons affected by Lewy body dementia can have changes in thinking and awareness (sometimes very rapidly), hallucinations - usually of people or animals, trouble sleeping because they are moving and “acting out” dreams, and stiffness of muscles along with a tremor. If two of these four symptoms occur in the setting of dementia then a person is likely to have Lewy body dementia. Remember, dementia is a change in cognition that affects a person’s ability to function in their day to day life.

Lewy body dementia is an underrecognized cause of neurodegenerative dementia because of how prevalent Alzheimer’s disease is and the overlap between the two. It can be difficult to sort out between the two, and ultimately both are progressive and fatal diseases. After diagnosis a person with Lewy body dementia usually lives between 5-8 years depending on their specific health and other risk factors. Treatment of the disease is very challenging and there is limited data regarding anything effective. Medications used in Alzheimer’s disease like donepezil and memantine may be used but ultimately will not slow or stop progression. Person-centered behavioral strategies and nonpharmacologic treatments should be considered in all progressive neurodegenerative diseases, but particularly in Lewy body dementia. As always, it is critical to make Advance Care Plans and discuss what Matters with those that are important in your life!

Key Points:

• Lewy body dementia is the third most common cause of dementia, it is progressive and fatal

• Lewy body dementia has many similarities with other neurodegenerative diseases

• Discuss what Matters with those important to you and make Advance Care Plans