Dementia with Lewy Bodies
Dementia with Lewy bodies is a complex brain disorder caused by abnormal protein deposits that affects thinking, movement, behavior, and sleep. It is one of the most common types of dementia, yet many people have never heard of it.
Table of contents
- What is dementia with Lewy bodies?
- What causes this condition?
- Signs and symptoms
- Who gets dementia with Lewy bodies?
- How is it diagnosed?
- Treatment options
- What to expect over time
What is dementia with Lewy bodies?
Dementia with Lewy bodies is one of the most common types of dementia (a decline in mental abilities that gradually gets worse over time). After Alzheimer’s disease, it is the second most common form of dementia. The condition is estimated to affect more than 1 million people in the United States and approximately 1.4 million individuals according to different sources.[1][2][3]
The name comes from Dr. Friedrich Lewy, a neurologist who discovered abnormal protein deposits while working in Dr. Alois Alzheimer’s laboratory during the early 1900s. These deposits are now called Lewy bodies.[1][3]
Dementia with Lewy bodies is sometimes confused with other brain diseases because it shares symptoms with both Alzheimer’s disease and Parkinson’s disease. This can make diagnosis challenging, especially in the early stages.[1]
LBD, DLB, Lewy body dementia, diffuse Lewy body disease
What causes this condition?
Dementia with Lewy bodies happens when clumps of a protein called alpha-synuclein build up inside brain cells. These abnormal deposits are called Lewy bodies. They form in areas of the brain that control thinking, memory, movement, and behavior.[1][2]
When Lewy bodies accumulate, they interfere with how brain cells work. The protein deposits damage neurons (nerve cells) in the brain and cause them to not work well and eventually die. Certain chemicals in the brain that act as messengers between cells are also affected.[1][4]
Scientists do not yet fully understand what causes these protein clumps to form or why some people develop them while others do not.[4]
Signs and symptoms
Dementia with Lewy bodies causes a mix of symptoms that can affect thinking, movement, mood, sleep, and automatic body functions. The degree of symptoms can vary widely from person to person, and not everyone will have every symptom.[4][5]
Changes in thinking and mental abilities: People may have trouble with attention, concentration, planning, problem-solving, and understanding visual information. Memory problems can occur but may not be as noticeable early on compared to Alzheimer’s disease.[4][5]
Fluctuations in alertness and attention: A distinctive feature of this condition is unpredictable changes in concentration, attention, alertness, and wakefulness. Someone may seem confused or distant one moment and then suddenly become more alert and focused. These fluctuations can happen over minutes or hours and may occur regularly.[2][4]
Visual hallucinations: Seeing things that are not really there is very common, occurring in up to 80% of people with this condition, often early on. People may see shapes, animals, or people that do not exist. Hallucinations involving sounds, smells, or touch are also possible but less common.[2][4]
Movement problems: Many people develop symptoms similar to Parkinson’s disease, including slow movement, stiff muscles, tremors (shaking), a shuffling walk, trouble with balance, and a lack of facial expression. These movement difficulties can increase the risk of falls.[2][4]
Sleep disorders: A common early symptom is REM sleep behavior disorder, where people lose the normal muscle paralysis that occurs during dream sleep and physically act out their dreams. This may appear years or even decades before other symptoms. People may also feel very sleepy during the day, have trouble falling or staying asleep, or experience restless legs at night.[4][5]
Behavioral and mood changes: Depression, anxiety, apathy (lack of interest), agitation, paranoia, and false beliefs (delusions) can all occur.[4][5]
Problems with automatic body functions: The part of the nervous system that controls automatic functions (the autonomic nervous system) can be affected. This may cause sudden drops in blood pressure when standing up, dizziness, fainting, problems with digestion and bowel movements (constipation is very common), difficulty controlling bladder and bowel function, trouble regulating body temperature, and changes in sweating. Loss of sense of smell may also occur and can be an early indicator of the disease.[2][4][5]
Symptoms typically start slowly and worsen over time. Some symptoms may come and go, and poor sleep can make other symptoms worse.[1][5]
Who gets dementia with Lewy bodies?
Dementia with Lewy bodies typically begins at age 50 or older, although sometimes younger people may develop it. The median age at diagnosis is around 76 years. The condition appears to affect slightly more men than women.[1][5]
Most cases are not inherited, and it rarely runs in families. However, having a biological family history of dementia with Lewy bodies or Parkinson’s disease can raise your risk. Certain genes, such as APOE and GBA, may also increase the chances of developing the condition, but having these genes does not mean you will definitely get the disease.[4][5]
How is it diagnosed?
Diagnosing dementia with Lewy bodies can be challenging because early symptoms are often confused with similar symptoms found in other brain diseases like Alzheimer’s disease or Parkinson’s disease. There is no single test that can diagnose the condition. Instead, diagnosis is based on symptoms, medical history, and ruling out other conditions.[1][7]
A diagnosis is typically made when someone has a gradual decline in thinking ability along with at least two of the following: fluctuations in alertness and attention, repeated visual hallucinations, movement problems similar to Parkinson’s disease, or REM sleep behavior disorder (acting out dreams during sleep).[4]
To make a diagnosis, healthcare professionals may use several approaches:[7][11]
- An assessment of symptoms and when they began
- A neurological and physical exam to check reflexes, strength, walking, muscle tone, eye movements, balance, and sense of touch
- Tests of mental abilities to assess memory, thinking skills, problem-solving, and language ability
- Blood tests to rule out other conditions with similar symptoms, such as vitamin deficiencies or thyroid problems
- Brain scans, such as MRI scans, CT scans, or SPECT scans, which can detect signs of dementia or other problems in the brain
A definitive diagnosis usually requires examining brain tissue after death (autopsy).[7]
Treatment options
Currently, there is no cure for dementia with Lewy bodies, and there are no treatments that can slow or stop the disease from progressing. However, symptoms can be treated, and many treatments can help control symptoms for several years.[1][7]
Medications for thinking and memory problems: Medicines called cholinesterase inhibitors are considered the standard treatment for cognitive symptoms. These include donepezil (Aricept), rivastigmine (Exelon), and galantamine (Reminyl). These drugs were developed to treat Alzheimer’s disease, but some researchers believe people with dementia with Lewy bodies may respond even better to them than people with Alzheimer’s. Rivastigmine is the only one approved by the FDA specifically for treating this condition. Another medication, memantine (Namenda), may also be helpful.[7][10]
Medications for movement problems: Movement symptoms may be treated with carbidopa/levodopa (Sinemet), a medication used for Parkinson’s disease. However, if symptoms are mild, it may be best not to treat them to avoid potential side effects.[10]
Medications for hallucinations and behavioral symptoms: If hallucinations are not disruptive or frightening, they may not need to be treated. When treatment is necessary, cholinesterase inhibitors are sometimes effective. Newer “atypical” antipsychotic medications may be used cautiously, with quetiapine or clozapine preferred by most experts. A newer medication, pimavanserin, was approved to treat psychosis in Parkinson’s disease and may be helpful.[10]
IMPORTANT WARNING: People with dementia with Lewy bodies are extremely sensitive to older “traditional” antipsychotic medications (such as haloperidol or thioridazine). Up to 50% of patients may have severe reactions, including worsening confusion, heavy sedation, immobility, or even a rare but life-threatening condition called neuroleptic malignant syndrome. These older antipsychotic medications should be avoided.[10][15]
Medications for sleep problems: For those who act out dreams during sleep, medications such as melatonin or clonazepam may help.[7][12]
Medications for other symptoms: Antidepressants may be given for depression, and medications may be used to help with blood pressure problems or other autonomic symptoms.[7][12]
Other therapies and support: In addition to medicines, several therapies and practical measures can help make life easier:[7][12]
- Occupational therapy to help with everyday tasks like getting dressed
- Speech and language therapy to improve communication or swallowing problems
- Physiotherapy to help with movement
- Psychological therapies, such as cognitive stimulation (activities and exercises designed to improve memory, problem-solving skills, and language ability)
- Relaxation techniques, such as massage, and music or dance therapy
- Social interaction, leisure activities, and memory cafes (drop-in sessions for people with memory problems and their caregivers to get support and advice)
- Home modifications, such as removing trip hazards, ensuring good lighting, and adding grab bars and handrails
What to expect over time
Dementia with Lewy bodies is a progressive disease, meaning symptoms start slowly and worsen over time. The disease lasts an average of five to seven years from the time of diagnosis to death, but the range can be anywhere from two to 20 years. How quickly symptoms develop and change varies greatly from person to person, depending on overall health, age, and severity of symptoms.[1][4]
In the early stages, symptoms can be mild and have less impact on daily functioning. As the disease worsens, people require more and more help with daily activities due to a decline in thinking and movement abilities. In the later stages, people may depend entirely on others for assistance and care.[1]
With proper treatment and support, many symptoms can be managed to improve quality of life. Research continues to improve our understanding of the disease, and advances in science may one day lead to better diagnosis, improved care, and new treatments.[1]
