Dementia with Lewy Bodies: Causes, Symptoms & Suggestions for Caregivers

Last Updated: September 01, 2018


People with Lewy Body Dementia (LBD), also called Dementia with Lewy Bodies (DLB), have a progressive decline in their memory and ability to think, similar to Alzheimer’s disease. However, the cognitive ability or alertness of a person with Lewy body dementia is more likely to fluctuate from one moment to the next, which is not like Alzheimer’s disease. Individuals with LBD also often have visual hallucinations (seeing things that aren’t there) and delusions (believing something that is not true). On the surface, people with LBD often have problems with movement that resemble Parkinson’s disease. This is because the same structures of the brain are affected in Lewy body dementia as in Parkinson’s disease.

There are several subtypes and different names for Lewy body dementia which include:

  • Diffuse Lewy body disease
  • Cortical Lewy body disease
  • Senile dementia of Lewy type
  • Lewy body variant of Alzheimer’s
  • Parkinson’s disease dementia (PDD)


How Common Is Lewy Body Dementia?

Dementia with Lewy bodies is the third most common type of dementia after Alzheimer’s disease and vascular dementia. According to the Lewy Body Dementia Association (LBDA), it is estimated that it affects 1.4 million individuals and families in the United States. The average age of onset is after 50 years of age, and most studies indicate the disease is slightly more common in men than women.

Lewy body dementia is progressive, like Alzheimer’s disease. This means that with current treatments, individuals who have it get worse with time in terms of function and ability. On average, a person diagnosed with LBD, lives approximately 5 to 8 years, although one can live as long as 20 years with the disease.

Approximately 50-80% of individuals with Parkinson’s disease go on to develop Parkinson’s disease dementia.


Causes of Lewy Body Dementia

Lewy body dementia is caused by the build-up of protein (alpha-synuclein), which forms abnormal deposits, named Lewy bodies, within the brain. Lewy bodies, named after the physician who discovered them, Friederich H. Lewy, are also found in the brains of those with Parkinson’s disease dementia and Alzheimer’s disease. Lewy bodies interrupt the normal function of brain cells by making it harder for them to communicate and by leading to cell death. Currently, the cause for the Lewy body protein buildup is not known. However, it is believed that environmental and genetic risk factors combined with aging play a role in the development of LBD.

It is also important to note that plaques and tangles that develop in the brains of people with Alzheimers disease are commonly found in the brains of people with Lewy Body Dementia and Parkinson’s dementia.

Having an immediate family member who had Lewy body dementia may increase your risk of getting this form of dementia. However, it often develops in persons who have no family history of the disease. Individuals may develop Lewy body dementia in combination with Alzheimer’s disease and/or Parkinson’s disease.


Symptoms of Lewy Body Dementia

In contrast to other forms of dementia that initially affect specific parts of the brain, Lewy bodies may develop in several different areas of the brain, which can cause a wider range of physical and behavioral symptoms. Common symptoms include difficulty with thinking, movement, sleep, memory, and depth and distance. There may be changes in mood and behavior, such as depression, anxiety, and agitation. In addition, bodily functions are also affected as the disease progresses, including the ability to regulate body temperature, bladder and bowel control, and blood pressure control. The range of possible symptoms includes many of the same ones seen in persons with Alzheimer’s disease and Parkinson’s disease.

Symptoms Similar to Parkinson’s Disease

  • Moving slowly and shuffling or shaking as the individual walks
  • Walking or standing very stiffly, with arms and legs flexed
  • Having a blank expression / stare into space
  • Balance issues / regular falls

Symptoms Similar to Alzheimer’s Disease

  • Having problems making new memories or recalling past memories
  • Becoming easily confused
  • Making odd or inappropriate decisions and actions

Symptoms Relatively Unique to Lewy Body Dementia

  • Symptoms becoming better or worse from moment to moment or hour to hour
  • Hallucinating, especially visually, as well as having delusions
  • Becoming active and violent at night, acting out dreams due to a condition that develops called rapid eye movement (REM) sleep disorder


Diagnosis of Lewy Body Dementia

It is often difficult for physicians to diagnose Lewy body dementia because it is similar to Alzheimer’s and Parkinson’s diseases. In addition, a patient may actually have a combination of these diseases. A person with Lewy body dementia may be diagnosed as having Alzheimer’s disease or vascular dementia when symptoms first appear.

Although there are no specific tests for Lewy body dementia, doctors can make a diagnosis based on symptoms and behaviors. For diagnosis, patients must have experienced a progressive or continuing decline in the way they are able to function in daily life. If this requirement is met, then a person may either be diagnosed as having “probable” Lewy body dementia or “possible” Lewy body dementia. According to the LBDA, diagnosis of probable Lewy body dementia requires that 2 of the 3 following characteristics be present, in addition to dementia. A diagnosis of possible Lewy body dementia only requires that 1 of the 3 are present, in addition to presenting with dementia.

Fluctuating cognition: Has trouble with his or her memory or abilities to stay alert and attentive. However, these symptoms may seem to get better or worse at times.
Visual hallucinations: Experiences and reacts to hallucinations that seem very real to him or her.
Parkinsonisms: Has some of the problems with movement and action similar to those associated with Parkinson’s disease.

Apart from the differences already noted, approaches to diagnosis and treatment of Lewy body dementia are similar to those of other forms of dementia. To learn more about diagnosing dementia (general), click here.


Treatment of Lewy Body Dementia

There is no cure available for Lewy body dementia at this time. Currently, there are also no medications approved by the FDA that specifically target this form of dementia. However, many individuals with the disease seem to benefit from the use of cholinesterase inhibitors.

Cholinesterase Inhibitors

Cholinesterase inhibitors are a group of drugs commonly prescribed to individuals with Alzheimer’s disease and other forms of dementia in order to slow the progression of the disease. For individuals with dementia, brain function decreases in part because their brain cells are no longer able to communicate with one another as well as previously. Cholinesterase inhibitors act to increase levels of the neurotransmitter acetylcholine. This is a chemical that helps brain cells (neurons) communicate and function better and plays a significant role in memory and learning. In practical terms, one may find that their loved one may be better able to remember names and details or perform activities with fewer problems when taking these medications.

There are four main cholinesterase inhibitors on the market:

Aricept® (generic name: donepezil)
Razadyne®, formerly known as Reminyl (generic name: galantamine)
Exelon® (generic name: rivastigmine)
Cognex® (generic name: tacrine) is another option, but is less commonly prescribed due to its serious potential side effects.

These medications are typically prescribed to individuals in the early to middle stages of dementia. Aricept® has been approved to treat severe dementia as well. It is important to remember that they only slow the progression of dementia and Alzheimer’s disease; they do not stop or reverse their course. Additionally, as an individual’s dementia advances, these medications are not able to balance out the damage that has already occurred. These medications typically help for only months to a few years.

In general, individuals who use cholinesterase inhibitors experience few side effects. The most commonly experienced side effects are gastrointestinal problems, such as nausea, diarrhea, vomiting, and loss of appetite.

These drugs, originally developed for persons with Alzheimer’s disease, help improve the brain’s ability to function. In fact, these drugs may even be more effective for Lewy body patients than for Alzheimer’s patients. Parkinson’s disease medications, such as Sinemet®, Parcopa®, and Stalevo®, may also be prescribed in the event that the person has increasing trouble with movement.

Persons with Lewy body dementia should not take antipsychotic drugs unless otherwise directed by a physician. Even though these medications can help manage hallucinations, in Lewy body patients, these drugs can make movement problems worse.

To learn more about how dementia is treated, in general, click here.


Suggestions for Caregivers

The most important thing to realize when caring for someone with Lewy body dementia is there is a need for flexibility. A person with LBD’s symptoms may change from day to day, becoming better or worse, and this can be difficult for caregivers to explain and handle. Remind yourself and others that your loved one is not simply “acting up.”

As Lewy body dementia progresses, inflicted individuals will also have an increasingly difficult time maintaining balance and moving about safely. Some caregivers find that suggesting the use of a cane or a walker is helpful. Additionally, there are several things you can do around the house to make sure that your loved one is able to move about safely and easily in order to prevent future accidents.

As with Alzheimer’s disease, Lewy body dementia will continue to progress and reduce your loved one’s ability to make appropriate decisions. Be sure to review our pages on legal and financial issues to learn what can be done before your loved one reaches the later stages of the disease.