Tributes have poured in for legendary actor Sir Patrick Stewart following his death at the age of 86, with his family revealing that he had been living with two forms of dementia.
The British actor, best known for portraying Captain Jean-Luc Picard in Star Trek and Professor Charles Xavier in the X-Men franchise, died at his Los Angeles home on October 28, 2026.
His death was announced the following day in a statement shared on his official social media accounts.
The statement confirmed that Stewart had experienced Alzheimer's disease and Lewy body dementia, conditions that had not previously been publicly disclosed.
His passing has prompted renewed attention to the signs of Lewy body dementia, particularly because the condition can sometimes be mistaken for other neurological disorders.
What are the nine symptoms of Lewy body dementia?
The nine signs highlighted by the Lewy Body Dementia Resource Center include visual hallucinations, acting out dreams, fluctuating alertness, Parkinson's-like movement changes, problems with spatial awareness, severe sensitivity to certain antipsychotic medications, mood and behavioural changes, difficulties regulating blood pressure or temperature, and subtle changes noticed by family members.
Not everyone with Lewy body dementia will experience all nine, and these symptoms can also have other causes.
Here is what each sign can involve.
1. Visual hallucinations
One of the more distinctive symptoms of Lewy body dementia is experiencing visual hallucinations.
A person may see people, animals or objects that are not actually present.
These experiences can appear remarkably realistic, making it difficult for the person to distinguish them from their surroundings.
Hallucinations can sometimes develop relatively early in the condition, even before significant memory problems become apparent.
2. Acting out dreams while sleeping
Another potential warning sign is REM sleep behaviour disorder.
During normal REM sleep, the body temporarily reduces most voluntary muscle activity, helping prevent people from physically acting out their dreams.
In people experiencing REM sleep behaviour disorder, this protective mechanism does not work as expected.
They may shout, kick, punch or make sudden movements while asleep.
In some cases, these behaviours can occur years before other symptoms of Lewy body dementia develop.
3. Sudden changes in alertness and thinking
People with Lewy body dementia may experience significant fluctuations in their ability to concentrate, remain alert or follow conversations.
Someone might appear relatively clear-headed at one point in the day before becoming noticeably confused or drowsy later.
These changes can occur over minutes or hours.
Family members may find the fluctuations particularly confusing because the person's abilities can seem to improve and deteriorate unpredictably.
4. Movement changes similar to Parkinson's disease
Lewy body dementia can also affect physical movement.
Symptoms may include muscle stiffness, slower movements, tremors and changes in walking patterns.
A person might begin taking shorter steps, shuffling while walking or experiencing difficulties with balance.
These symptoms can resemble those associated with Parkinson's disease.
Doctors consider the timing of movement and cognitive symptoms when distinguishing dementia with Lewy bodies from Parkinson's disease dementia.
5. Problems with spatial awareness and depth perception
Another possible sign involves difficulties interpreting visual information and judging distances.
Someone might struggle to navigate familiar spaces, reach accurately for objects or judge where furniture and doorways are positioned.
Everyday activities such as pouring a drink, getting dressed or moving around the home may become more challenging.
These difficulties can occur even when a person's eyesight itself has not significantly deteriorated.
6. Severe reactions to certain antipsychotic medications
People with Lewy body dementia can be unusually sensitive to some antipsychotic medications.
These medicines are sometimes prescribed for severe behavioural or psychological symptoms, but in people with Lewy body dementia they can occasionally cause serious adverse reactions.
Potential complications include worsening stiffness and movement problems, pronounced sedation and, in rare cases, life-threatening reactions.
Clinical guidance recommends particular caution when considering these medicines for people with Lewy body dementia.
This is an important treatment-related warning rather than a symptom that someone would necessarily notice before diagnosis.
7. Depression, anxiety and changes in motivation
Mood and behavioural changes can also occur in people living with the condition.
Some may experience depression, anxiety or apathy, including a reduced interest in activities they previously enjoyed.
Others may become increasingly withdrawn or struggle with motivation.
These symptoms can appear alongside changes in movement, sleep or thinking.
However, depression and anxiety are common conditions with many possible causes and do not, by themselves, indicate dementia.
8. Problems regulating blood pressure and body temperature
Lewy body dementia can affect the autonomic nervous system, which controls many involuntary bodily functions.
This may lead to blood pressure dropping when someone stands up, causing dizziness, lightheadedness or fainting.
Some people also experience changes in sweating or difficulty regulating their body temperature.
Other possible autonomic symptoms include constipation and urinary problems.
These symptoms should be assessed by a healthcare professional because they can also be caused by medications and other medical conditions.
9. A gradual sense that something has changed
The final sign highlighted in the original report is less specific but may be familiar to some families.
Relatives sometimes recall noticing subtle changes in a loved one's behaviour, attention or everyday abilities before understanding what was happening.
These observations might involve a person seeming less engaged, becoming unusually confused or struggling with tasks they previously managed comfortably.
However, a general feeling that something is wrong is not a recognised diagnostic symptom on its own.
Persistent changes in thinking, behaviour or daily functioning are worth discussing with a healthcare professional.
What is Lewy body dementia?
Lewy body dementia is a progressive neurological condition associated with abnormal deposits of a protein called alpha-synuclein in the brain.
These deposits, known as Lewy bodies, interfere with the normal functioning of brain cells.
The broader term includes dementia with Lewy bodies and Parkinson's disease dementia.
Although it shares some symptoms with Alzheimer's disease, Lewy body dementia often involves more prominent changes in alertness, visual perception, sleep and movement.
Memory problems can develop, but they may be less noticeable during the early stages than in Alzheimer's disease.
There is currently no cure, although treatments and supportive care can help manage certain symptoms.
What did Sir Patrick Stewart's family say?
Stewart's family confirmed his death in a statement released on October 29.
The announcement said the actor had died at home in Los Angeles, cared for by his wife, Sunny Ozell, following a period living with Alzheimer's disease and Lewy body dementia.
It also paid tribute to his extraordinary acting career and the impact he had on audiences around the world.
Stewart became internationally recognised for his portrayal of Captain Jean-Luc Picard in Star Trek: The Next Generation, later reprising the character in several films and the series Star Trek: Picard.
He was also widely admired for playing Professor Charles Xavier in the X-Men films and for his extensive Shakespearean stage career.
His family did not disclose when he received either dementia diagnosis.
When should someone seek medical advice?
Anyone experiencing persistent changes in memory, thinking, movement, sleep or behaviour should consider speaking with a healthcare professional.
The NHS advises arranging a GP appointment if someone may be showing early signs of dementia.
A doctor can assess symptoms, consider other possible explanations and arrange further investigations where appropriate.
Experiencing one or more of the signs listed above does not necessarily mean a person has Lewy body dementia.
Nevertheless, recognising concerning changes and seeking professional assessment can help people access appropriate treatment, advice and support.
Sources: UNILAD, October 30, 2026; Sir Patrick Stewart family statement; NHS guidance on dementia with Lewy bodies; National Institute on Aging; Lewy Body Dementia Resource Center; NICE clinical guidance.
