Lewy body dementia symptoms usually come as a mix: seeing things that are not there, acting out dreams while asleep, thinking and alertness that rise and fall through the day, and movement changes that look like Parkinson’s. Doctors look for this combination when they are deciding whether someone has Lewy body dementia (LBD), and no single sign settles it. If you are reading this because of something you have seen in a relative or yourself, the sections below walk through each sign, how the diagnosis is made, and what the options look like.
How Lewy body dementia differs from Alzheimer’s disease
Alzheimer’s disease and Lewy body dementia are listed as different types of dementia, though UCSF Health says researchers don’t yet understand whether dementia with Lewy bodies is a distinct disease or a variation of Alzheimer’s or Parkinson’s disease. The National Institute on Aging lists Lewy body dementia alongside Alzheimer’s, frontotemporal dementia and vascular dementia as the main types.
Lewy body dementia can also occur alone or alongside Alzheimer’s or Parkinson’s disease, according to UCSF Health’s Lewy body dementia page. If you want a plain comparison of the two dementias, read alzheimer disease vs dementia next.
What is Lewy body dementia?
MedlinePlus, the National Library of Medicine’s consumer health site, describes LBD as one of the most common types of dementia in older adults. It happens when Lewy bodies, abnormal deposits of a protein called alpha-synuclein, build up in parts of the brain that control memory, thinking and movement. MedlinePlus also says researchers don’t know exactly why these deposits form.
There are two types. Dementia with Lewy bodies (DLB) starts with thinking problems that look similar to Alzheimer’s disease, and movement and other symptoms follow. Parkinson’s disease dementia starts as a movement disorder and develops into dementia later. MedlinePlus notes that both types cause the same changes in the brain.
What triggers Lewy body dementia?
No single trigger has been identified. What researchers know is where the changes happen and what they are made of: protein deposits in the brain cells that control memory, thinking, movement and visual perception. The NHS says it is not clear why the deposits develop or exactly how they damage the brain. Age and family history are the known risk factors, covered in the next section.
At what age does Lewy body dementia typically start?
MedlinePlus says the biggest risk factor is age, and most people who get it are over 50. People with a family history of LBD are also at higher risk. The NHS says that DLB usually occurs in people with no family history of the condition, though there have been very rare cases that seem to run in families. The NHS page (last reviewed March 2023) says dementia is rare in people under 65.
What are the first signs of Lewy body dementia?
The Lewy Body Resource Center lists nine early warning areas. The table below pulls the main ones together with the other guides. Not everyone has every sign, and they can appear in different combinations and at different times.
| Sign | What it looks like |
|---|---|
| Visual hallucinations | Detailed, real-seeming visions, often of people, children, animals or moving patterns. They usually happen when the person is awake and alert. The Lewy Body Resource Center calls them one of the first and most distinctive signs. |
| Acting out dreams | Talking, shouting, punching or thrashing during sleep, sometimes leading to falls. MedlinePlus calls this REM sleep behavior disorder and says it may be the earliest symptom in some people, appearing several years before others. |
| Changing alertness and thinking | Clear and capable at one hour, drowsy or confused at another. MedlinePlus says these changes usually happen from day to day but can also happen within the same day. |
| Movement changes | Slowness, shorter shuffling steps, stiff arms and legs, less arm swing when walking, and sometimes a resting tremor. The NHS lists slow movement, stiff limbs and tremors. |
| Trouble with space and reading | Misjudging distances, bumping into doorframes, getting lost in familiar places, and losing your place when reading. |
| Mood and behavior | Depression, anxiety and apathy (loss of interest in daily activities), which the LBDA lists as extremely common in LBD. Delusions (false beliefs) and paranoia can also occur. |
| Blood pressure and body temperature | Dizziness or fainting when standing up, sweating or feeling too hot or cold, constipation, and urinary problems. |
| Reaction to some medicines | A severe reaction to antipsychotic drugs. UCSF Health notes that people with LBD tend to be highly sensitive to drugs that affect the brain. |
If several of these sound familiar, the Lewy Body Resource Center suggests writing down what you see, when it started, how often it happens, and any patterns, and bringing those notes to your appointment.
Is there a 3 minute test for Lewy body dementia?
There is no single test for it. MedlinePlus says a doctor usually takes a detailed history from the patient and a caregiver, does physical and neurological exams, rules out other conditions with blood tests and brain imaging, and runs neuropsychological tests of memory and thinking. The NHS describes the same workup, including a number of tasks and questions to assess mental abilities. If someone offers you a short test, ask what it measures and how it fits into that full assessment.
What is the 1 year rule for Lewy body dementia?
The timing of movement and thinking problems decides which type a person has. MedlinePlus says that if cognitive symptoms start within a year of movement problems, the diagnosis is dementia with Lewy bodies. If cognitive problems start more than a year after the movement problems, the diagnosis is Parkinson’s disease dementia. MedlinePlus adds that knowing the type helps the doctor understand how the disease is likely to affect the person over time.
Lewy body dementia symptoms vs Parkinson’s disease
The two conditions share movement symptoms, and the order in which they appear is the main clue. The Penn Memory Center explains the two types of Lewy body dementia, and the Lewy Body Resource Center describes the timing difference.
| Feature | Lewy body dementia (DLB) | Parkinson’s disease |
|---|---|---|
| Timing of movement and thinking problems | Movement problems develop around the same time as thinking problems or shortly after | Movement problems usually appear years before any thinking changes |
| Where it starts | Thinking problems that look similar to Alzheimer’s disease | Slowed movement, muscle stiffness, tremor and a shuffling walk |
| Other features | Visual hallucinations, sleep disorders, fluctuating alertness | Movement is the central feature; Parkinson’s disease dementia develops later for some people |
If you are trying to tell them apart, a movement disorder neurologist or behavioral neurologist has more experience with LBD than a general practitioner, according to the Lewy Body Resource Center.
Lewy body dementia symptoms in women
The symptoms above are the ones the NHS and MedlinePlus describe for anyone with LBD. If you are a woman noticing these signs in yourself or someone close to you, the next step is the same: write down what you see and when, and take it to a GP.
Lewy body dementia symptoms checklist
The Lewy Body Dementia Association publishes an LBD Diagnostic Symptom Checklist. The first page is a patient-friendly list of symptoms that can be completed in advance and taken to a doctor. The second page has the physician-oriented diagnostic criteria. Bringing it to a first appointment gives the doctor a clear record of what you have noticed.
Do people with Lewy body dementia know they have it?
Sometimes, at least early on. The Lewy Body Resource Center says people with LBD sometimes know that their visions are not real, and that this insight can fade as the disease progresses. Many people do not remember the sleep episodes the next morning, because they happen during deep sleep. Family members are often the ones who notice the changes first, which is why the Lewy Body Resource Center encourages writing down specific examples.
How fast does Lewy body dementia progress?
The sources do not agree on pace. The NHS says LBD tends to develop slowly and get gradually worse over several years. UCSF Health says that unlike Alzheimer’s disease, LBD often starts rapidly, with a fast decline in the first few months, and that later there may be some leveling off. The NHS also says how quickly it gets worse varies from person to person. MedlinePlus describes it as progressive: symptoms start slowly and get worse over time.
Life expectancy with Lewy body dementia
The NHS page (last reviewed March 2023) says the average survival time after diagnosis is around 5 to 7 years. The NHS adds that this is highly variable and some people live much longer. UCSF Health gives the same range: a patient can survive from five to seven years with the disease. Treat those numbers as averages, not a forecast for any one person.
What is the last stage of Lewy body dementia like?
MedlinePlus says in the early stages symptoms can be mild and people can function fairly normally. In the later stages, people need more help with thinking and movement, and they often cannot care for themselves. The NHS says home-based help will usually be needed, and some people will eventually need care in a care home. The Penn Memory Center links a home safety checklist and NIH legal and financial planning resources.
What treatments are available for Lewy body dementia?
There is no cure. The NHS says there is currently no cure for dementia with Lewy bodies and no treatment that will slow it down, but there are treatments that can help control some of the symptoms, possibly for several years. Which options fit you is a decision for you and a neurologist or GP.
| Option | What the sources say | Limits to know |
|---|---|---|
| Medicines for symptoms | The NHS lists medicines to reduce hallucinations, confusion, drowsiness, movement problems and disturbed sleep. | UCSF Health says medicines must be closely monitored, because people with LBD can have adverse effects from drugs that affect the brain. Doses are usually started low and raised slowly. |
| Cholinesterase inhibitors | UCSF Health says patients have been especially responsive to these, which are used to treat Alzheimer’s, to improve memory and cognition and reduce hallucinations. | Only a clinician can decide whether one is suitable. |
| Parkinson’s medicines | UCSF Health says levodopa or other Parkinson’s medicines may be given to ease stiffness and improve walking. | Also reviewed by a clinician because of sensitivity. |
| Antipsychotics | UCSF Health says tranquilizers and antipsychotics are sometimes used to lessen agitation or hallucinations. | The Lewy Body Resource Center warns that standard antipsychotics can cause sudden worsening of movement symptoms, extreme sedation, high fever or neuroleptic malignant syndrome. |
| Therapies | The NHS lists physiotherapy, occupational therapy and speech and language therapy, plus cognitive stimulation. MedlinePlus says music or art therapy may reduce anxiety. | Therapies target symptoms such as movement, daily tasks and communication, per the NHS. |
| Supplements | The NCCIH ginkgo page says a large study called GEM, of more than 3,000 people age 75 or older, found no difference in dementia rates between ginkgo and placebo over a median of 6 years. It also says ginkgo extract may have a modest benefit for dementia symptoms, but the evidence is inconsistent. | The GEM study measured dementia of any type and Alzheimer’s disease. |
| Clinical trials | The National Institute on Aging says volunteers are needed for clinical trials exploring diagnosis, treatment and prevention strategies for various types of dementia. | Eligibility varies by trial. |
The NIH Office of Dietary Supplements says some research links more omega-3 from food with lower dementia risk, but not all studies agree. That finding concerns food intake and dementia risk, not treatment for LBD. See the NIH omega-3 fact sheet.
The Penn Memory Center notes that doctors sometimes prescribe memory medicines that are often used for Alzheimer’s disease, and that some people may benefit from melatonin for sleep. It also says that because people with LBD are often sensitive to medications, all medications should be reviewed by a doctor and monitored for side effects.
Ask your clinician which of these medicines are licensed for LBD where you live, and which ones they would use and why.
What should people with Lewy body dementia avoid?
The biggest caution across these guides is antipsychotic medicine. The Lewy Body Resource Center says some people with LBD have severe reactions to antipsychotics, and that a past bad reaction to drugs like haloperidol or risperidone is a red flag for possible LBD. Mention any past reaction to a doctor, especially before a hospital visit. The Lewy Body Resource Center notes that some people are diagnosed only after such a reaction in an emergency room.
- Medicines that can affect thinking. The National Institute on Aging lists antihistamines for allergy relief, sleep aids, antipsychotics, muscle relaxants and some bladder and stomach-cramp medicines as drugs that can impair cognition in older adults.
- Alcohol. The National Institute on Aging advises limiting alcohol, and notes that some medicines can be dangerous when mixed with it.
- Stopping prescribed medicine on your own. The National Institute on Aging says not to stop any prescribed medicine without consulting your health care provider first.
Sleep problems are part of LBD for many people. The LBDA says evaluation by a sleep specialist can help identify and treat these issues, and that acting out dreams can cause injuries.
Can I do the everyday brain-health routine myself instead?
The routines below are general brain-health habits, not a treatment for LBD. The National Institute on Aging’s guidance on what is known about preventing Alzheimer’s disease says researchers can’t say for certain whether healthy lifestyle changes protect against dementia, but these steps may help reduce risk. The same guidance lists controlling high blood pressure, being physically active and making healthy dietary choices. The NIA’s cognitive health guide adds getting enough sleep, generally seven to nine hours each night, and treating hearing or vision loss. Penn Memory Center also lists staying socially and mentally active, managing mood and a heart-healthy diet. For more on general risk, see how to reduce dementia risk.
Because LBD symptoms such as hallucinations, movement changes and blood pressure swings need medical assessment, these routines work best alongside a diagnosis and a care plan.
Be careful with supplement ads for brain health
If a video or ad promises brain benefits from a supplement, remember that, unlike drugs, dietary supplements are not approved by the U.S. Food and Drug Administration before they are sold to the public. The Federal Trade Commission’s health products compliance guidance says the Dietary Supplement Health and Education Act of 1994 (DSHEA) governs structure and function claims in labeling, but the FTC assesses those claims in advertising separately. Ask what the claim is based on, and whether the study tested people with the condition you are dealing with.
Who to see and what to bring to the appointment
Start with your GP. The NHS says a GP can run simple checks and refer you to a memory clinic or another specialist for further tests. Movement disorder and behavioral neurologists have more experience with LBD than general practitioners, according to the Lewy Body Resource Center. UCSF Health and other academic centers provide comprehensive assessments. The National Institute on Aging’s ADEAR Center can help families find resources at 800-438-4380.
Bring your symptom notes and a current list of every medicine and supplement. Useful questions to ask:
- Which type of LBD do you think this is, and what timing are you basing that on?
- Which of my current medicines could affect my thinking, sleep or movement?
- Can I have a sleep evaluation?
- If a medicine is needed for agitation or hallucinations, what are the risks for me?
- Are there clinical trials or support groups you would suggest for my family?
The fastest next step is the one you can take this week: write down the symptoms you have seen, when they started and how often they happen, then book an appointment with your GP and ask for a referral to a specialist.
By the Global MH Summit Research Team
This article is for general information purposes only and does not constitute medical advice. Consult your doctor or qualified healthcare provider before making changes to your health routine.