Lewy Body Dementia
Lewy body dementia (LBD) is a neurodegenerative disorder in which abnormal structures called Lewy bodies are found in the brain when an autopsy is completed after death. The Lewy body proteins were discovered in the early 1900s; however, 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 well known. The diagnostic criteria for LBD was then 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. Oher people develop memory loss and confusion first and then the Parkinson’s symptoms come later. This variation in initial symptoms complicates the diagnostic process. Often it will take several years before a diagnosis of LBD is made by a physician.
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
- Confusion
- Decision making capacity declines
- Confusion and memory loss fluctuate more than in Alzheimer’s disease
- Visual hallucinations and/or delusions are common
- Depression
- 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 diagnostic workup for LBD generally includes collection of family history, neuropsychological testing, bloodwork, neurological exam, medical history, and a magnetic resonance imaging (MRI) scan. There is no medication developed specifically for Lewy body dementia but, based on present symptoms, the physician will initiate treatment.
The medications for Alzheimer’s disease, which are cholinesterase inhibitors, may be initiated by the attending physician to help treat LBD. The cholinesterase inhibitors include donepezil (Aricept), Rivastigmine (Exelon) or Galantamine (Razadyne). Should movement symptoms be primary, the 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. If movement symptoms were helped by the Carbidopa/Levodopa, the patient and 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 LBD. This means families or the patient’s support network learn new ways to respond to these hallucinations or delusions; however there may be a time when an antipsychotic medication is the only options. For many patients, though, antipsychotic medications are dangerous and carry a black box warning. The newer antipsychotics are generally prescribed first, because they have less side effects. Once prescribed, the patient needs to be monitored closely for side effects. All side effects should be reported to the physician immediately.