Your dad has had odd spells for a year. Some days he's sharp and joking; other days he stares into space and can barely follow a conversation. He's mentioned seeing children in the backyard who aren't there, and your mom says he thrashes and shouts in his sleep. His walking has slowed, too. When the neurologist finally says "Lewy body dementia," it's almost a relief to have a name for it, followed quickly by a long list of questions.
Lewy body dementia, or LBD, is one of the most common types of dementia in older adults1. It affects thinking, movement, sleep and behavior, and its symptoms can look like Alzheimer's disease, Parkinson's disease or even a psychiatric illness. That makes it hard to diagnose and hard to live with. This guide explains what families need to know and how to help. It's general information. Your parent's doctors will guide treatment. For an overview of dementia types, see early signs of dementia.
What Lewy body dementia is
Lewy body dementia happens when abnormal deposits of a protein called alpha-synuclein, known as Lewy bodies, build up in parts of the brain that control memory, thinking and movement1. Researchers don't know exactly why the deposits form. The same protein builds up in Parkinson's disease1.
Age is the biggest risk factor, and most people who develop LBD are over 50. A family history raises the risk somewhat1. Dementia with Lewy bodies most often appears between ages 50 and 852.
Two types: dementia with Lewy bodies and Parkinson's disease dementia
LBD includes two related conditions that cause the same brain changes and, over time, similar symptoms. The main difference is which symptoms come first1:
- Dementia with Lewy bodies. Thinking problems come first, sometimes looking like Alzheimer's, with movement problems, hallucinations and sleep problems following1.
- Parkinson's disease dementia. Starts as Parkinson's disease, with slow movement, stiffness, tremor and a shuffling walk. Dementia develops later1.
If your parent already has Parkinson's, see our guide to Parkinson's care for older adults.
Symptoms of Lewy body dementia
- Fluctuating attention and alertness. Good days and bad days, or sudden changes within a day, including staring spells12.
- Visual hallucinations. Seeing things that aren't there, often people or animals2.
- Movement problems. Slowness, stiffness, trouble walking, tremor and poor balance1.
- REM sleep behavior disorder. Acting out dreams by talking, shouting or moving in sleep. It can appear years before other symptoms1.
- Thinking problems. Trouble with attention, planning, problem solving and judging distances. Memory may be less affected early on than in Alzheimer's12.
- Mood and behavior changes. Depression, anxiety and apathy1.
- Body changes. Dizziness or fainting when standing, constipation, bladder problems, drooling and a reduced sense of smell2.
Our guide to dementia hallucinations explains how to respond calmly when your parent sees things that aren't there.
How LBD differs from Alzheimer's and Parkinson's
In Alzheimer's disease, memory loss is usually the earliest and main symptom. In LBD, early problems with attention, alertness and visual thinking, plus hallucinations and acting out dreams, are more typical, while memory may hold up better at first2. In Parkinson's disease, movement problems come first and dementia, if it develops, comes years later1.
LBD can also occur alongside Alzheimer's changes in the brain. It's also different from vascular dementia, which is caused by strokes and other damage to blood flow, and from frontotemporal dementia, which usually starts younger with personality or language changes. Because the treatments and cautions differ, a careful diagnosis by an experienced doctor, often a neurologist, matters1. For how care needs change across dementias in general, see stages of dementia care needs.
How it's diagnosed
There's no single test for LBD. The doctor takes a detailed history from both the patient and family, does physical and neurological exams, and orders tests to rule out other causes1. Family observations matter a great deal. Keep notes on good and bad days, hallucinations, sleep behavior, falls and dizziness, and bring them to appointments.
Stages and life expectancy
LBD gets worse over time. Early on, symptoms may be mild and people can manage fairly well. As it progresses, people need more help because of problems with thinking and movement. In later stages, they often can't care for themselves1.
- Early stage. Sleep behavior changes, mild thinking problems, occasional hallucinations or confusion, maybe mild movement changes.
- Middle stage. More frequent fluctuations, more falls, more help with daily tasks, and growing movement problems.
- Late stage. Severe thinking and movement problems, trouble swallowing and speaking, and full-time care1.
Life expectancy varies. People with dementia with Lewy bodies typically live about five to seven years after diagnosis, though some live longer2. Ask your parent's doctor what to expect for them. Falls, pneumonia and swallowing problems often shape the later course, so preventing falls and watching for coughing at meals are two of the most useful things families can do. Regular check-ins with the care team help you adjust the plan as needs change.
Treatment and medicine cautions
There's no cure for LBD, but treatment can help with symptoms1:
- Medicines. Some can help with thinking, movement or psychiatric symptoms1.
- Physical therapy. For movement and balance problems.
- Occupational therapy. To make everyday activities easier.
- Speech therapy. For swallowing and for speaking loudly and clearly1.
- Counseling and support groups. For the person and the family1.
- Music or art therapy. May reduce anxiety and improve well-being1.
Daily care tips for families
- Plan around fluctuations. Schedule appointments and outings for your parent's best time of day, and expect bad days.
- Prevent falls. Clear walkways, add grab bars, and have your parent stand up slowly to avoid dizziness. See fall prevention.
- Keep sleep safe. Move furniture away from the bed and consider a lower bed if your parent acts out dreams.
- Respond calmly to hallucinations. If they aren't upsetting, there's often no need to argue.
- Watch swallowing. Coughing at meals can signal swallowing problems. Ask about a speech therapy evaluation.
- Manage constipation and bladder problems. Mention them to the doctor2.
- Keep a medicine list. Carry it with you, with a note about LBD sensitivity.
Person-centered approaches help with many behavior changes. See person-centered dementia care, sundowning and dementia anger and aggression.
Hospital stays and emergencies
Hospital stays can be especially hard for people with LBD. A new setting, poor sleep, infections and new medicines can all bring on sudden confusion, more hallucinations or a sharp drop in movement. Prepare a one-page sheet with the diagnosis, current medicines, medicines to avoid or use with caution, your parent's usual abilities, and your contact details. Give it to the emergency team and ask that it go in the chart.
Stay with your parent as much as you can, bring glasses and hearing aids, and ask the team to keep them moving and on a normal sleep schedule. If confusion gets worse, ask whether an infection, dehydration or a new medicine could be the cause. Our hospital discharge planning guide can help with the next step.
Driving, money and home safety
Problems with attention and judging distances can make driving unsafe even when memory seems fine. Talk with the doctor about a driving evaluation, and plan other ways to get around. See when should an older adult stop driving.
Fluctuating judgment can also make your parent vulnerable to scams and money mistakes. Set up automatic bill payments, watch accounts for unusual activity, and put a trusted person in charge of finances when needed. See managing an elderly parent's finances. At home, secure stairs, remove trip hazards, and add night lights for nighttime wandering. See dementia wandering.
Choosing care as needs grow
Many people with LBD live at home for years with family and paid help. As falls, nighttime behaviors and care needs increase, families often consider memory care or a nursing home. Ask any community how staff are trained to handle hallucinations, fluctuations and fall risk, and how they work with neurologists on medicines. See how to choose memory care and memory care vs. nursing home.
Late-stage care and hospice
In the late stage, people with LBD may have trouble swallowing, frequent infections and weight loss, and need full-time care1. Palliative care can help at any stage, and hospice when a doctor certifies six months or less to live34. Medicare contractors look at things like the ability to walk, speak and eat when judging hospice eligibility for dementia5. Read hospice for dementia and end-of-life signs in dementia.
Talking with your parent about the diagnosis
Many people with LBD understand their diagnosis, especially early on and on good days. Ask your parent how much they want to know, and let them take part in decisions. Hallucinations can be frightening or embarrassing, so reassure them that these are part of the illness and not a sign that they're losing their mind. Explaining the condition to grandchildren and friends in simple words helps everyone respond with patience. Keep talking with your parent about what matters most to them as the illness changes. Their wishes about where to live, which treatments to accept and how to spend their good days can guide the family through harder decisions later, and recording those wishes now spares everyone guesswork.
Planning and support
Because LBD can affect judgment early, plan legal and financial matters soon after diagnosis while your parent can take part. Put an advance directive and powers of attorney in place6. See power of attorney for an elderly parent.
Caring for someone with LBD is demanding, especially with unpredictable days and nighttime behaviors. Join a support group, accept help, and schedule breaks. See respite care and caregiver burnout.
