Dementia Services Information and Development Centre

Dementia with Lewy bodies

Dementia with Lewy body (DLB) is a form of dementia that occurs because of abnormal deposits of a protein called ‘lewy bodies’ inside the brain's nerve cells. Frederich Heinrich Lewy first described these abnormal clumps in 1912. Dementia with Lewy body usually affects the areas of the brain that involve thinking and movement. It accounts for between 5-15% of all dementias.

Other names for Lewy body dementia include:

  • Lewy body disease 
  • Dementia with Lewy bodies 
  • Lewy body variant of Alzheimer's disease
  • Diffuse Lewy body disease 
  • Cortical Lewy body disease 

Symptoms of Lewy body Dementia

DLB usually progresses quickly and a person with this illness may have symptoms akin to Parkinson's disease and Alzheimer's disease.  These include: 

  • Changes in thinking and reasoning
  • Short term memory impairments
  • Parkinson's symptoms, such as rigid and stiff muscles, tremors, loss of dexterity, stooped posture and shuffling movement. 
  • Visual hallucinations, vivid and occurring frequently. 
  • Delusions
  • Language difficulties
  • Psychological symptoms such as depression and anxiety

Diagnosis of Lewy body Dementia

No single test can diagnose Lewy body dementia. Doctors diagnose the condition by differential diagnosis, ruling out other possibilities. Assessment may include physical and neurological examinations. 

Risk factors for Lewy body dementia

Lewy body dementia is more common in men than women and affects people at a slightly younger age than Alzheimer’s disease.  We still do not know what exactly causes this illness.  It may be linked to Parkinson’s disease and Alzheimer’s disease as lewy bodies are often found in the brains of people with Parkinson's disease or Alzheimer's disease. If a family member has Lewy body dementia, there may be a higher risk of developing Alzheimer’s disease. 

Treatment for Lewy body Dementia 

There is no cure yet for Lewy body dementia. Sometimes doctors prescribe medications to treat symptoms such as those associated with Parkinson's disease, cognitive impairment and hallucinations. Recent research suggests that acetyl cholinesterase inhibitors (anti-dementia drugs) can benefit people with a diagnosis of DLB.

It is very important that all medications are monitored because some drugs adversely affect some people with Lewy body Dementia. Neuroleptic anti psychotic medications (such as haloperidol) and benzodiazepines (such as Valium) can cause extreme reactions in some individuals with DLB. Side effects include motor related symptoms, loss of cognitive function and/or development of muscle rigidity.

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