Dementia with Lewy bodies (DLB) is a type of progressive dementia that leads to a decline in thinking, reasoning and independent function because of abnormal microscopic deposits that damage brain cells over time.  Symptoms of Lewy disease closely resemble those of Alzheimer’s and Parkinson’s disease.  Doctors often find it difficult to make a definitive diagnosis of Lewy body disease because the symptoms of the three diseases are so  similar.

Dementia with Lewy bodies  is caused by a build-up of Lewy bodies – accumulated bits of alpha-synuclein protein in an area of the brain that controls particular aspects of memory and motor control.  Symptoms include a progressive cognitive decline combined with three defining features:

  1. pronounced fluctuations in alertness and attention such as a frequent drowsiness, periods of time spent staring into space or disorganized speech.
  2. recurrent visual hallucinations, and
  3. Parkinsonian motor symptoms such as rigidity and the loss of spontaneous movement.

Researchers have not yet identified any specific causes of dementia with Lewy bodies. Most people diagnosed have no family history of the disorder, and no genes linked to this form of dementia  have been conclusively identified.  While there is no cure for dementia of Lewy bodies, early diagnosis and a comprehensive medical treatment approach can extend the quality of life and independence for individuals with this diagnosis.