What is Lewy body dementia (LBD)?

Lewy body dementia (LBD), is a brain disorder in which proteins, called alpha-synucleins, build up inside certain neurons (brain cells). These clumps of proteins, called Lewy bodies, cause damage to neurons in areas of the brain that affect mental capabilities, behavior, movement and sleep.

In elderly patients, LBD is one of the most common causes of dementia. The symptoms of LBD may closely resemble those of other neurological disorders, including Alzheimer’s disease and Parkinson’s disease.

Doctors do not know why you or your loved one develop LBD while others do not. There is no cure for LBD, but your symptoms can be managed with certain medications, like cholinesterase inhibitors (Aricept®, Exelon®, Razadyne®) and levodopa. You or your loved one may also benefit from non-medical treatments like physical therapy and speech therapy.

Who is most at risk for getting Lewy body dementia (LBD)?

While anyone can develop Lewy body dementia (LBD), those most at risk are over the age of 50. Men are slightly more likely to develop LBD than women.

How common is Lewy body dementia (LBD)?

Lewy body dementia (LBD) is one of the most common causes of dementia in older people. It is estimated that as many as 1.4 million people live with this disorder in the U.S. Most diagnoses are in people over the age of 50.

What causes Lewy body dementia (LBD)?

Lewy body dementia (LBD) is a broad term covering two separate neurological disorders: dementia with Lewy bodies and Parkinson’s disease dementia. The same biological changes to the brain cause both disorders.

A buildup of Lewy bodies (proteins called alpha-synucleins) causes LBD. Lewy bodies build up in neurons located in certain areas of the brain that are responsible for behavior, movement, and cognitive ability.

Doctors do not know why you or your loved one develop LBD while others do not. There is some thought that the combination of mutation in a person’s genes, environmental risk factors and natural aging might lead to the development of LBD in some people. Research into specific causes is ongoing.

What are the symptoms of Lewy body dementia (LBD)?

Lewy body dementia (LBD) symptoms may resemble those of other neurological disorders, like Alzheimer’s disease and Parkinson’s disease. LBD affects each person differently, and symptoms vary in severity.

Common symptoms of LBD include:

  • Decline in thinking, including memory, planning, problem solving, decision making and ability to focus and to understand information in visual form.
  • Visual hallucinations, or seeing things that are not there.
  • Reduced alertness, attention and ability to concentrate.
  • Parkinsonism, a movement disorder with symptoms including slowness, tremors, stiffness, balance problems, soft voice, difficulty swallowing, reduced facial expression and shuffling walk.
  • Visuospatial difficulties, including decreased depth perception, trouble recognizing familiar objects and impaired hand-eye coordination.
  • Delusions, or beliefs with no basis in reality.
  • Changes in behavior and mood including anxiety, agitation, aggression, apathy, depression and paranoia.
  • Changes in sleep patterns.

Other symptoms include:

  • Acting out while sleeping. Your loved one may act out their dreams during a phase of sleep cycle called rapid eye movement (REM). Sometimes this happens years before their LBD diagnosis. Often called REM sleep behavior disorder (RBD), this condition is described as frequent movements, such as flailing or punching, with yelling or speaking while sleeping. People living with RBD often have difficulty separating dreams from reality when they wake up.
  • Changes in normal body functions. Body temperature may waver, blood pressure may fluctuate (causing fainting episodes and falls) and loss of bowel and bladder control.

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