Lewy Body Disease

Original Editor - Henry Tan, Kevin Lam, Alex Mong, Andrew To as part of the Queen's University Neuromotor Function Project

Top Contributors - Henry Tan, Andrew To, Alex Mong, Lucinda hampton, Kim Jackson, Kevin Lam, Vidya Acharya, Claire Knott, 127.0.0.1, Evan Thomas and Lauren Lopez  

Introduction

As Parkinson's disease becomes the fastest-growing neurological condition worldwide, physiotherapists are increasingly encountering its complex cousin - Lewy Body Dementia (LBD). With up to 80% of Parkinson's patients developing dementia during their disease journey, understanding LBD is essential. LBD is a progressive degenerative brain disorder marked by dementia, psychosis, and symptoms of Parkinsonism and autonomic disturbances that cause a progressive decline in functional independence.

Two Faces, Same Challenge: LBD presents in two main forms that directly impact your treatment approach:

1. Parkinson's Disease Dementia (PDD): Movement problems first, then cognitive decline after a year or more
2. Dementia with Lewy Bodies (DLB): Cognitive issues appear first or within the first year of movement symptoms

Both conditions share the same underlying brain pathology - toxic alpha-synuclein protein clumps called Lewy bodies - but their different timelines create distinct rehabilitation needs.

The Physiotherapy Reality

These patients present unique challenges:

• Fluctuating function: Good days and bad days that affect exercise tolerance
• Complex symptoms: Combining movement disorders with cognitive changes
• Fall risk: Higher than typical Parkinson's due to cognitive-motor interactions
• Medication limitations: Poor response to standard Parkinson's treatments

Why This Matters Now

LBD represents the second most common neurodegenerative dementia, yet remains underdiagnosed and poorly understood. As physiotherapists, recognizing the signs early and adapting interventions accordingly can significantly impact patient outcomes and family quality of life.

The growing prevalence means LBD patients are moving from specialty clinics into mainstream physiotherapy practice.

Epidemiology

• Occurs in older patients (onset typically in 50-70 years of age), and is sporadic. However a family history of LBD and Parkinson disease will increase a person's risk.
• LBD is one of the most common causes of dementia (accounting for up to 20% to 30% of cases) along with Alzheimers disease (AD).

Etiology

The etiology of LBD is unknown. Genetics, environmental factors, and changes linked to aging, may have a role and research is still ongoing.

LBD has been found to be strongly linked to a protein called alpha-synuclein. The abnormal accumulation of this protein in certain regions of the brain causes dramatic cognitive and motor deficits affecting behaviour, mood, movement, and thinking.

Clinical Presentation

The clinical features of LBD are the consequence of the blockage of information transfer from the striatum to the cortex, more notably the frontal lobe.

Core features:

1. Fluctuating cognitive impairment, especially in executive function, attention and alertness
2. Visuospatial impairment, including visual hallucinations (detailed and vivid)
3. REM sleep disorder that may precede cognitive decline
4. Concurrent parkinsonian symptoms may be present but are less common, more frequently occurring years after the onset of dementia, e.g. early extrapyramidal features (dystonia, akathisia, muscle rigidity, bradykinesia, tremor, tardive dyskinesia

Dementia with Lewy body disease can be diagnosed if 2 or more core clinical features are present with or without the presence of indicative diagnostic biomarkers or presence of only one core clinical feature but with one or more indicative diagnostic biomarkers. The diagnosis should not be made on the basis of biomarkers alone. Watch this 3 minute video showing a personal story "It happened little by little. First he would forget things, then he'd lose track of what he was doing. LBD took over the life of the man you're about to meet."

Pathophysiology

The characteristic feature of dementia with Lewy bodies is the accumulation of Lewy bodies throughout the brain. These intracellular inclusions result from the aggregation of misfolded α-synuclein. Neurofibrillary tangles are also present, however they lack an amyloid core, as seen in AD.

Regions of the brain affected by LBD include: cerebral cortex, limbic cortex, hippocampus, midbrain, brainstem.

Source (http://labiotech.eu/major-cns-disease-milestones-in-biotech-2015/)

Diagnostic Procedures

It is important to realise that there is a significant overlap between many neurodegenerative diseases, and that a clear-cut distinction between entities is not always possible. No precise test can accurately diagnose LBD. A thorough assessment is useful to reach an alternative working diagnosis (or rules out similar conditions):

• Detailed history and examination
• Assessment of cognitive function
• Blood tests (e.g., vitamin B12 levels, chemistry panel, thyroid profile, syphilis, HIV) to rule out other causes of dementia

• Imaging studies (e.g., CT scan, MRI scan, SPECT scan, PET scan)
• Cerebrospinal fluid examinations have no significant role when conducted in these patients
• Sleep evaluation for REM sleep behavior disorder
• I-metaiodobenzylguanidine (MIBG) scintigraphy, a well-known tool to evaluate cardiac sympathetic denervation in the Lewy body-related disorders shows low uptake of MIBG in the Lewy body-related disorders, including Parkinson’s disease, dementia with Lewy bodies

Management

There is no effective treatment for LBD and the condition is progressive. Pharmacological Management includes cholinesterase inhibitors. They treat the cognitive symptoms of LBD and are central to treatment. eg rivastigmine, galantamine, and donepezil. Acetylcholine is an important neurotransmitter for memory. People with eg LBD have reduced levels present in their brains. Cholinesterase inhibitors inhibit this enzyme , improving brain network communication..

The other pharmacological agents are used to treat behavioural symptoms.

• Home care nurses play a crucial role in regularly assessing the patient and providing support services.
• Education of the caregiver is essential, the loved ones needing to be aware of the behavior changes, hallucinations, and fluctuations in cognition. Caregivers have to monitor the patient closely as they have a love level of functioning, with most unable to perform ADLs and are prone to falls and aspiration pneumonia.
• The pharmacist needs to educate caregivers that no medical therapy will cure the cognitive changes and the drugs simply manage behaviour and motor deficits ( and many have adverse effects).
• A mental health nurse is often needed as depression is common. Close communication between members of the interprofessional team is vital to improve outcomes.

Prognosis

LBD has a poor prognosis, with an average life expectancy from initial diagnosis to death 5-8 years. Death usually occurs from one of the many complications eg falls, immobility, cardiac complications, medication side effects, pneumonia, swallowing problems, suicide.

Physiotherapy Management

Balance training

Physiotherapy for Lewy Body Disease is similar to that of Parkinson’s Disease. It can help manage parkinsonism that is prevalent in LBD by providing intervention such as strengthening and flexibility exercises and gait training. Aerobic exercise should be included to optimise cardiovascular fitness. Physiotherapy is especially helpful in improving balance and postural stability to minimize the risk of falls. With the addition of exercise, non-motor symptoms such as cognition, sleep and fatigue will improve. As the disease progresses and the dementia increases, exercise can be hard to do. Therefore, it is important to incorporate exercise in the early and middle stages of Lewy Body Disease. A study suggests that a high-intensity functional exercise program has positive outcomes on balance in these patients.

Tips to help make exercise easier to maintain:

• Provide visual cues by demonstrating exercises
• Play upbeat music or music the person enjoys
• Arrange exercise classes or include the support/care-person
• Do exercises in sitting
• Make exercise fun and enjoyable