Lewy Body Dementia
Lewy body dementia is a neurodegenerative disorder in which abnormal structures called “Lewy bodies” are found in the brain when an autopsy is completed after death. While the Lewy Body proteins were discovered in the the early 1900s it was not until 1996 when a group of physicians and scientists developed a consensus report on the diagnosis of LBD that the diagnosis became more well known. This diagnostic criteria was refined in 2007.
People with Lewy body dementia have symptoms of both Alzheimer’s disease and Parkinson’s disease. Symptoms develop differently in each individual. Some people develop the Parkinson’s symptoms first and the confusion and memory loss come later. However other people develop memory loss and confusion initially and Parkinson’s symptoms come later. This variation in initial symptoms complicates the diagnostic process and often it will take several years before a diagnosis of Lewy body dementia (LBD)is made by your physician. This delay in diagnosis or change in diagnosis is very frustrating to the person with LBD and their family. However it is this gradual development of new symptoms that helps to clarify and refine the diagnosis.
Parkinson’s symptoms in LBD:
- loss of spontaneous movement (bradykinesia)
- rigidity (muscles feel stiff and resist movement)
- tremor (less common in LBD than in Parkinson’s disease)
- shuffling walk
- face has a flat, unexpressive look
Alzheimer's disease symptoms in LBD:
- memory loss
- decision making capacity declines
- confusion & memory loss fluctuate more than in Alzheimer’s disease
- visual hallucinations and/or delusions are common
- Rapid Eye Movement (REM) sleep behavior disorder
Families often report being very confused by the terminology related to Lewy body dementia. At times the disease is referred to as dementia with lewy body’s (DLB) or Parkinson’s disease dementia (PDD. The symptoms of Lewy body dementia vary from individual to individual. The earlier stages of the disease in particular are difficult to differentiate. However the symptoms usually begin as either movement (Parkinson’s) symptoms or memory (Alzheimer’s) symptoms.
The diagnostic workup for Lewy body dementia is the same as for Alzheimer’s disease and generally include familial history, neuropsychological testing, bloodwork, neurological exam, medical history and MRI scan.
There is no medication developed specifically for Lewy body dementia. However based on your symptoms the physician will initiate treatment. The medications for Alzheimer’s disease which are cholinesterase inhibitors may be initiated by your physician. The cholinesterase inhibitors include donepezil (Aricept), Rivastigmine (Exelon) or Galantamine (Razadyne) These medications can be helpful to many people with Lewy body dementia.
Should movement symptoms be primary your physician may start treatment with Carbidopa/Levodopa, a commonly used medication for Parkinson’s disease. While some people with Lewy body dementia are helped by Carbidopa/Levodopa others develop hallucinations. Often if the Carbidopa/Levodopa is stopped the hallucinations with stop also. However if movement symptoms were helped by the Carbidopa/Levodopa you and your physician will need to discuss how to proceed.
Hallucinations or delusions are frequent symptoms in Lewy body dementia even in the absence of Carbidopa/Levodopa. Behavioral interventions are usually the first step in managing these symptoms in Lewy Body dementia. Families learn new ways to respond to these hallucinations or delusions. However there may be a time when an antipsychotic medication is the only options. The common treatment for these symptoms are antipsychotic medications. However for many people with Lewy body dementia antipsychotic medications are dangerous and carry a black box warning. The newer antipsychotics are usually the first prescribed because they have less side effects. Once prescribed the person needs to be monitored closely for side effects and report these to your physician immediately.