Introduction

Lewy bodies represent the unusual buildup of proteins in the brain (also known as alpha-synuclein). When these proteins cluster, they interfere with the chemical signals needed for movement and cognitive function. Lewy body dementia (LBD) is a common type of dementia, characterised by the presence of Lewy bodies. It is a degenerative disease of the brain meaning that it progressively becomes worse over time.¹

If caught early, it is possible to slow the progression of the disease and improve outcomes for patients living with Lewy body dementia, although unfortunately there is no cure.² The Lewy Body Society, is a charity dedicated solely to Lewy body dementia. Alzheimer’s Research equally has useful resources on Lewy body dementia, as does Dementia UK.

This article will flag the important signs to look out for if you suspect that someone close to you may be in the early stages of Lewy body dementia. 

Cognitive symptoms

Cognition refers to the ability to learn, think, reason and make decisions. Cognitive ability is usually impaired by Lewy body dementia as the protein that accumulates causes changes to the brain, resulting in some of the behaviours listed below.³

Fluctuations in attention and alertness

A person affected by Lewy body dementia may periodically experience feelings of confusion and drowsiness, and lose the ability to focus on tasks.^4,5 Examples of some specific behaviours to look out for include:

• Being unable to concentrate
• Appearing ‘zoned out’ or unaware of their surroundings
• Alternatively, being unusually alert
• Falling asleep in the daytime 

Memory impairment

Problems with short-term memory can occur as a result of Lewy body dementia. Short-term memory specifically refers to the retention of recent information. This can manifest as:

• Forgetting recent events
• Not being able to recall information from a recent conversation
• Misplacing objects
• Being unable to find the right words 

Visual hallucinations

Hallucinations are when you see things that aren’t there (such as animals, people or other objects), although they appear realistic. People with Lewy body dementia can experience these hallucinations.⁶ 

Motor symptoms

Motor symptoms relate to issues with movement, both intentional and involuntary.

Parkinsonism

Motor symptoms of Lewy body dementia can overlap with the triad classically associated with Parkinson’s disease, namely:

• Tremors (trembling or shaking)
• Rigidity (stiffness)
• Bradykinesia (slow movement, like a shuffling walk)

Half of people affected by Lewy body dementia will exhibit these symptoms in the early stages of the disease. The overlap between Parkinson’s disease and Lewy body dementia can make it challenging to diagnose, but only one of the symptoms in the Parkinson’s triad is required to consider Lewy body dementia as a diagnosis.⁷

Balance issues and falls

Coordination can also be affected in Lewy body dementia. Individuals may have trouble balancing when standing, or difficulty walking in a straight line, resulting in more frequent falls.

Sleep disturbances

As mentioned before, people with Lewy body dementia may have trouble sleeping. There are two particular signs to be aware of if you suspect someone has Lewy body dementia:

REM sleep behaviour disorder (RBD)

This is a core symptom of Lewy body dementia that is often found earlier than other manifestations of the disease. Also known as dream enactment, individuals may physically act out their dreams, by yelling or flailing around. This arises as muscle paralysis that usually occurs during rapid eye movement sleep doesn’t take place in the normal way.⁵

Excessive daytime sleepiness

People with Lewy body dementia are more prone to feeling tired throughout the day, even if they had adequate sleep the night before. Take note of behaviours that reflect this, such as:

• Frequent naps during the daytime
• Sudden episodes of sleep

Sleep disturbances tend to be an early sign, preceding the more severe symptoms seen in the later stages of Lewy body dementia.

Mood and behavioural changes

Lewy body dementia can affect the mind in many different ways, including altering our emotional state.

Depression and anxiety

People with Lewy body dementia may experience changes to their mood, such as feelings of sadness and anxiety. They may mask this by putting up a facade of happiness, but it should be noted to look for these symptoms:

• Isolation from others or avoiding social events
• Not engaging in hobbies or losing interest in things that previously made them happy
• Restlessness
• Irritability

Apathy

Apathy is a lack of motivation or interest in daily activities. It is one of the most frequent changes in behaviour that can be seen in people with Lewy body dementia.⁸ This can manifest as:

• Being reliant on others to engage socially
• Disinterest in activities
• Reduced interactions with loved ones 

Changes in personality

Personality changes are one of the most noticeable symptoms of Lewy body dementia. You may notice personality shifts in someone or them behaving out of character. Look for signs such as:

• Having a short temper and lashing out verbally or physically
• Being suspicious of others
• Fear and paranoia

Autonomic nervous system dysfunction

Long-term accumulation of Lewy bodies in the brain results in changes to the autonomic nervous system, which governs involuntary processes in the body. 

Blood pressure fluctuations

People with Lewy body dementia may experience a drop in their blood pressure when they stand up, known as orthostatic hypotension. It can lead to dizziness and fainting spells as the brain temporarily doesn’t get enough blood to function properly. Blurred vision is another symptom that can occur as a result.

Bladder and bowel issues

A further sign that someone might have Lewy body dementia is loss of control when urinating or issues with bowel movements, such as:

• Constipation
• Leaking faeces by accident when passing wind
• Urinary incontinence
• Difficulty urinating

Summary

Lewy body dementia has multiple signs, ranging from behavioural, physical and cognitive changes. If you notice these early signs in someone close to you, contact your GP or another healthcare professional to help reach a diagnosis. This can bring peace of mind to you and your loved ones. Early intervention in Lewy body dementia can be helpful for a patient’s quality of life and managing symptoms.