What is Lewy Body Dementia?

Facts

Lewy body dementia (LBD) is a progressive brain disease and the second leading cause of degenerative dementia in the elderly. The clinical name, “dementia with Lewy bodies” (DLB), accounts for up to 20% of all dementia cases, or 800,000 patients in the US. Over 50% of Parkinson’s disease patients develop “Parkinson’s disease dementia” (PDD), which accounts for at least 750,000 patients. (PDD is also a Lewy body dementia.)

Other names for the Lewy body dementias are:

• Lewy body disease (LBD)
• Diffuse lewy body disease (DLBD)
• Cortical Lewy body disease (CLBD)
• Lewy body Variant of Alzheimer's (LBV)(LBVA)
• Parkinson's disease with dementia (PDD)

In the early 1900’s, while researching Parkinson's disease, the scientist Friederich H. Lewy discovered abnormal protein deposits that disrupt the brain's normal functioning. These Lewy body proteins are found in an area of the brain stem where they deplete the neurotransmitter dopamine, causing Parkinsonian symptoms. In Lewy body dementia, these abnormal proteins are diffuse throughout other areas of the brain, including the cerebral cortex. The brain chemical acetylcholine is depleted, causing disruption of perception, thinking, and behavior. Lewy body dementia exists either in pure form, or in conjunction with other brain changes, including those typically seen in Alzheimer's disease and Parkinson's disease.

Diagnosing LBD

Diagnosis

An experienced clinician within the medical community should perform a diagnostic evaluation. If one is not available, the neurology department of the nearest medical university should be able to recommend appropriate resources or may even provide an experienced diagnostic team skilled in Lewy body dementia.

A thorough dementia diagnostic evaluation includes physical and neurological examinations, patient and family interviews (including a detailed lifestyle and medical history), and neuro-psychological and mental status tests. The patient’s functional ability, attention, language, visuospatial skills, memory and executive functioning are assessed. In addition, brain imaging (CT or MRI scans), blood tests and other laboratory studies may be performed. The evaluation will provide a clinical diagnosis. Currently, a conclusive diagnosis of LBD can be obtained only from a postmortem autopsy for which arrangements should be made in advance. Some research studies may offer brain autopsies as part of their protocols. Participating in research studies is a good way to benefit others with Lewy body dementia.

Medications

Medications are one of the most controversial subjects in dealing with LBD. A medication that doesn't work for one person may work for another person.

Prescribing should only be done by a physician who is thoroughly knowledgeable about LBD. With new medications and even “over-the-counter,” the patient should be closely monitored. At the first sign of an adverse reaction, consult with the patient's physician. Consider joining the online caregiver support groups to see what others have observed with prescription and over-the-counter medicines.

Risk Factors

Advanced age is considered to be the greatest risk factor for Lewy body dementia, with onset typically, but not always, between the ages of 50 and 85. Some cases have been reported much earlier. It appears to affect slightly more men than women. Having a family member with Lewy body dementia may increase a person’s risk. Observational studies suggest that adopting a healthy lifestyle (exercise, mental stimulation, nutrition) might delay age-associated dementias.

Clinical Trials

The recruitment of LBD patients for participation in clinical trials for studies on LBD, other dementias and Parkinsonian studies is now steadily increasing.

For those interested in participating in LBD research, please check our clinical trials page.

Prognosis and Stages

No cure or definitive treatment for Lewy body dementia has been discovered as yet. The disease has an average duration of 5 to 7 years. It is possible, though, for the time span to be anywhere from 2 to 20 years, depending on several factors, including the person’s overall health, age and severity of symptoms.

Defining the stages of disease progression for LBD is difficult. The symptoms, medicine management and duration of LBD vary greatly from person to person. To further complicate the stages assessment, LBD has a progressive but vacillating clinical course. It is typical to observe a significance progression, followed by regression back to a higher functioning level. Downward fluctuations are often caused by medications, infections or other compromises to the immune system, but may also be due to the natural course of the disease