What is Lewy body dementia?

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

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 some people develop LBD while others do not. There is no cure for LBD, but symptom management is possible with certain medications, like cholinesterase inhibitors (Aricept®, Exelon®) and levodopa. Many people also benefit from non-medical treatments like physical therapy and speech therapy. After diagnosis, people usually live an average of 5 to 7 years.

Who is most at risk for getting Lewy body dementia?

While anyone can develop 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 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.

What causes 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 some people develop LBD while others do not.

What are the symptoms of Lewy body dementia?

Lewy body dementia 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:

  • Changes in thinking, including the ability to remember things, to plan, to focus and to understand information in visual form
  • Visual hallucinations, or seeing things that are not there
  • Parkinsonism, a movement disorder of the central nervous system that might involve slowness, tremors, stiffness and/or trouble walking
  • Visuospatial difficulties, including decreased depth perception
  • Delusions, or beliefs with no basis in reality
  • Changes in behavior and sleep patterns

Many people with Lewy body dementia act out their dreams during a phase of sleep cycle called REM. Sometimes this happens years before their LBD diagnosis. Often called REM Sleep Behavior Disorder (RBD), this condition is characterized by frequent movements, such as flailing or punching, with yelling or speaking while sleeping. People living with RBD often have difficulty distinguishing dreams from reality when they awaken.

It is also possible to experience changes to normal body functions. Blood pressure may fluctuate, causing things like fainting episodes, and people may lose bowel and bladder control or have difficulty swallowing. Some people with LBD become more aggressive or depressed. Some people might have problems with body temperature—being too hot or too cold.

Many people with LBD become very sensitive to antipsychotic medications, like risperidone (Risperdal®). This sensitivity may mean they have more frequent hallucinations. It also can make cognitive function worse. In many cases, doctors avoid prescribing antipsychotic medications to people living with LBD. If symptoms develop from the medications, doctors will recommend an alternative treatment.

When should I call my doctor?

If you develop symptoms of Lewy body disease, contact your doctor for a thorough evaluation. Your doctor will develop a treatment plan based on your diagnosis and symptoms.

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