Toronto Dementia NetworkLewy Body DementiaLewy body Dementia is a form of progressive dementia identified by abnormal structures in brain cells called “Lewy bodies*”. These are distributed in various areas of the brain. A major component of Lewy bodies is a protein called alpha synuclein. The mechanism that leads to the formation of Lewy bodies is unknown. Unlike Alzheimer's disease where eventually massive numbers of neurons die, in Lewy body Dementia, only 10-15% of neurons disappear, although function is eventually impaired in the surviving neurons. Certain areas of the brain are affected in Lewy body Dementia that are not usually affected in Alzheimer's disease. Lewy body Dementia can occur by itself, or together with Alzheimer or Parkinson’s Disease. It accounts for 15-20% of all dementias. Other names for Lewy body Dementia include: Diffuse Lewy body Disease, Cortical Lewy body Disease, Lewy body Disease, Senile Dementia of Lewy Type, Dementia with Lewy bodies and Lewy body variant of Alzheimer's disease. *(The disease was discovered in 1912 by Dr. Levi, which
became “Lewy” in the translation from German.) How does Lewy Body Dementia affect the person?In Lewy body Dementia, there is progressive loss of memory, language, reasoning and other higher mental functions, such as calculation. The person may have difficulty with short-term memory, finding the right word and sustaining a train of thought. An individual may also experience depression and anxiety. Lewy body Dementia usually has a rapid progression. Memory difficulties may not be an early symptom, but can develop as Lewy body Dementia progresses. Marked fluctuations in confusion can vary from hour to hour or week to week. Visual hallucinations (seeing things which are not real) are common and can be worse during times of increased confusion. The visual hallucinations are often recurrent and typically consist of people, children or animals intruding into the home. People with the disease may also make errors in perception, for example, seeing faces in a carpet pattern. Some features of Lewy body Dementia can resemble Parkinson’s Disease. These include rigidity (stiffness of muscles), tremors (shaking), stooped posture and slow shuffling movements. Sensitivity to medication, especially some sedatives, may exaggerate these symptoms. How is Lewy body Dementia assessed?Assessment should include a neurological exam that emphasizes gait, posture and the degree of rigidity. Blood pressure will also be taken and cognitive functioning should be tested. Who does Lewy body Dementia affect?Lewy body Dementia is more common in men than in women. What causes Lewy body Dementia?At present, there is no known cause of Lewy body Dementia and risk factors have not been identified. In rare cases, the disease is passed from generation to generation. Is there a treatment for Lewy Body Dementia?At present, there is no cure for Lewy body Dementia. It is sometimes possible to treat symptoms such as depression, and unpleasant hallucinations can be reduced with medication. Parkinson symptoms can also be treated. However, due to the multiple features of Lewy body Dementia with Parkinson symptoms, management of these diseases can be difficult because treatment of one symptom may be achieved at the expense of another. Treatment is often individualized for each person focusing on treating the symptoms in order of severity to avoid or prevent over-medication. For more information:
The contents of this document are provided for information purposes only, and do not represent advice, an endorsement or a recommendation, with respect to any product, service or enterprise, and/or the claims and properties thereof, by the Alzheimer Society of Canada. The Information Sheet is not intended to replace clinical diagnosis by a health professional. Source: May 2005 - Research- Related Dementia - Lewy Body Dementia - Alzheimer Society of Canada. Toronto Dementia Network. 2007 |