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Lewy Body Dementia (LBD)

LBD, also called Dementia with Lewy Bodies (DLB), is a neurodegenerative disease. It’s the second most common type of dementia after Alzheimer’s. About 1.4 million people in the US and 10+ million worldwide are afflicted. 

Table of Contents

What is Lewy Body Dementia?

Let’s start with the name. Lewy is named after scientist Dr. Fritz Lewy. In 1912, Dr. Lewy was researching Parkinson’s Disease (PD). 

He noticed deceased patients had unusual clumps of proteins in their brains, which were called Lewy bodies. Back then, Lewy bodies were associated exclusively with PD.

Then in 1976, Dr. Kenji Kosaka first identified Lewy Body Dementia as a unique disease. Both PD and LBD patients have Lewy bodies as a pathological signature.

LBD is an elusive and lesser understood brain disease than Alzheimer’s and Parkinson’s. It causes a progressive decline in both cognitive and movement abilities.

According to the National Institute of Health, LBD is associated with the toxic accumulation of a misfolded protein called alpha-Synuclein in the brain.  

Normal Synuclein is a protein produced by most brain cells. Occasionally, these healthy proteins can change their structure and become what’s called misfolded proteins, aka prions.

We refer to prions as Proteins Gone Rogue. In this case, misfolded Synuclein is also called alpha-Synuclein. 

Misfolded Synuclein may induce other healthy Synuclein to misfold. As this process self-replicates and accumulates in the brain, they form Lewy bodies.

Lewy bodies cause brain cell death.

This short video explains prions, which play a significant role in Lewy Body Dementia.

What Causes Lewy Body Dementia?

Why Lewy bodies form is still unknown. 

Prion build-ups keep your brain from making the right amount of two important chemicals:

  • Acetylcholine affects cognitive functions, including memory and learning abilities.  
  • Dopamine affects movement, emotion, and sleep.

Risk Factors


The gene ApoE4 increases the risk for Alzheimer’s. It also increases the risk of Lewy Body Dementia.

Family History

People with two or more immediate family members with LBD have a higher risk. This can be due to epigenetic or genetic links. More research studies are needed to understand the connection better.  


Similar to other brain diseases, aging also increases the risk of LBD.


In short, massive cell death in two regions of the brain triggers the disease.

People with LBD often experience confusion due to cell death in the neocortex. This brain region controls memory, associations, and learning.

Cell death in the midbrain region causes motor symptoms similar to people with Parkinson’s.

Furthermore, research studies found that over 50% of LBD late-stage patients also show two other types of misfolded proteins:

  • Misfolded Abeta, and
  • Misfolded Tau

Misfolded Abeta and Tau are known to drive Alzheimer’s Disease.

Scientists and researchers have yet cracked the code on what causes normal proteins to misfold.

First Signs of Lewy Body Dementia

LBD initially presents as an atypical Alzheimer’s with motor control issues or atypical Parkinson’s with cognitive symptoms.

One striking early sign is visual hallucinations. There can also be sound, smell, or touch hallucinations.

These symptoms often recur and are uncharacteristic in people with pure Alzheimer’s or Parkinson’s.

Four Stages of Lewy Body Dementia

Here are the four stages with major symptoms:

  1. Prodromal stage
    Symptoms include sleep disorders, hallucinations, depression, and dizziness.

  2. Early-stage
    Symptoms often overlap with Alzheimer’s or Parkinson’s. These include memory loss, occasional disorientation, stiffness/tremors, and loss of balance.

  3. Intermediate stage
    Early-stage symptoms become more pronounced.

  4. Late-stage
    Patients are unable to function independently and may require 24-hour care. In addition, poor nutrition, infections, falling, and pneumonia may lead to terminal illness.

Lewy Body Dementia Symptoms

Active Dreaming

Physically acting out dreams; punching, kicking and yelling. As a result, falling out of bed often occurs. This condition is called REM sleep behavior disorder (RBD).


A condition associated with a lack of motivation and indifference to one’s surroundings. 


Struggling to differentiate what is real and what is not. For example, a person might believe others are out to get them when they are just trying to help.

Difficulty Concentrating

Adults often find concentration increasingly difficult as they age. But this is far more pronounced in people with LBD, with a twist! For instance, they may be able to concentrate on a complex matter and yet, struggle with a simple task.


A growing, persistent feeling of sadness.

Fluctuating attention

Wide range of attention swings. These include bouts of drowsiness, prolonged periods of blank stares, long daytime naps, or jumbled speech.


Various kinds of hallucinations, including visual, audio, scent, and/or feel.


Did you know your face has 43 muscles to help express emotions? Through the nervous system, the brain controls these muscles to respond accordingly.

Unfortunately, people with LBD often develop hypomimia, aka Parkinson’s mask – an expressionless face.

High Sensitivity to Medication

Extreme sensitivity to antipsychotic treatments. These drugs can elevate body tremors, muscle stiffness, further deteriorate mental sharpness, and worsen hallucinations.

Impairment of Visuospatial Ability

Our two eyes work together for triangulation to help judge direction and distance. Unfortunately, people with Lewy Body Dementia lose this ability. As a result, even reaching for the remote can be difficult.

Loss of Balance

The diminishing ability to judge distance and depth causes balance loss. As a result, stumbles and falls happen more often, leading to broken/fractured bones, concussions, and more.

Personality Changes

These behavior and mood changes include:

  • Lost interest in life-long hobbies
  • Becoming repetitive
  • Lowered general emotional response

Shifting Symptoms

One of the startling characteristics is how quickly and randomly the symptoms shift. They can dramatically change from day to day, hour to hour, even minute to minute.

Mixed Symptoms

People with Lewy Body Dementia (or Parkinson’s) have Lewy bodies in their brains. In addition, LBD patients may also develop plaques and tangles associated with Alzheimer’s.

The overlapping symptoms present an enormous challenge for accurate diagnosis. So let’s take a look at these mixed symptoms:

Alzheimer's-like Symptoms

Patients undergo progressive cognitive problems that can be indistinguishable from Alzheimer’s. These symptoms include:

  • Diminished reasoning
  • Loss of logic
  • Decline of executive function
  • Memory loss
  • Hallucinations

Parkinson's-like Symptoms

Simultaneously, patients exhibit the movement symptoms of Parkinson’s, including:

  • Rigid muscles
  • Movement disorders
  • A shuffling walk
  • Leaning toward one side
  • Sleep disorders
  • Autonomic changes affecting heart rate, blood pressure, and urinary incontinence

How is Lewy Body Dementia Diagnosed?

An Arduous Diagnostic Journey

Patients go through a painfully long diagnostic journey. The Lewy Body Dementia Association (LBDA) conducted an extensive survey. Nearly 1,000 caregivers participated, revealing these startling facts:

About 15% of patients saw at least five doctors before being accurately diagnosed.

  • On average, patients visited three doctors before receiving the correct diagnosis. 
  • 1 in 4 was correctly diagnosed within three months of symptom onset.
  • Only 23% were accurately diagnosed within a year.
  • For the other 50%, it took longer than one year for a correct diagnosis.

Overall, 10% of patients waited 3+ years to receive an accurate diagnosis!

Currently, doctors diagnose patients after symptoms appear. As a result, patients undergo a long asymptomatic stage, in which their brains suffer damage without detection.

So when the body shows signs of Lewy Body Dementia, it’s the late stage. The brain has suffered irreversible damage over a long period of time. Consider the case of Robin Williams

Robin Williams received confirmation that he had LBD after his autopsy, which has been the only method to confirm the diagnosis.

Our breakthrough SYNTap™️ Biomarker Test is poised to transform this sad reality through accurate early detection.

Robin Williams

Robin Williams received confirmation that he had LBD after his autopsy, which has been the only method to confirm the diagnosis.

Our breakthrough SYNTap™️ Biomarker Test is poised to transform this sad reality through accurate early detection.

Frequent Misdiagnosis

80% of LBD patients are misdiagnosed because of mixed disease symptoms.

Why has it been so challenging to detect Lewy Body Dementia accurately in the past? Here are two primary reasons:

  1. We could not detect misfolded Synuclein in the brain using conventional methods.
  2. Overlapping symptoms made accurate diagnosis nearly impossible without biomarker testing.

Consider the following scenarios:

Initially misdiagnosed as Alzheimer's

Let’s say a person shows memory loss and modest disruption of executive function.  Doctors would likely diagnose Alzheimer’s.

Later that same person also shows motor or autonomic symptoms; doctors would most likely change to an LBD diagnosis.

Blog Featured Image - Abeta plague Alzheimer's
Assay About Parkinson’s disease

Initially misdiagnosed as Parkinson's

Let’s say a person shows Parkinsonian motor issues. If there are no cognitive symptoms, doctors likely diagnose Parkinson’s.

If dementia signs appear after more than one year, doctors likely change the diagnosis to Parkinson’s Disease Dementia (PDD).

However, if the above scenario happens within one year, doctors likely change the diagnosis to Lewy Body Dementia.

As you see in these examples, brain disease diagnosis is subject to change as symptoms evolve.

Keep in mind the symptoms are far more complicated and challenging in real life. As a result, the frustrating diagnostic journey exasperates patients, loved ones, and the care team.

Misdiagnosis leads to mistreatment, causing more harm to patients due to drug side effects.

Beginning of the End for LBD

Thanks to scientific innovations, the SYNTap Biomarker Test is here! This breakthrough test identifies misfolded Synuclein in the brain.

Doctors can order the SYNTap Test to diagnose Lewy Body Dementia accurately.

Amprion’s groundbreaking biomarker test empowers research in racing to a cure!

Lewy Body Dementia Treatment

Currently, no drug can cure LBD. However, some medicines aim at improving symptoms.

Unfortunately, certain medications can make things worse. For example, antipsychotic treatments can exacerbate confusion, Parkinsonism, and sedation. Sometimes even death.

Due to these harmful side effects, Early Detection is key.

Knowing early gives people more options and precious time.

Using this extra time proactively, the person and the care team can:

  • Better navigate the disease journey
  • Delay symptom onset through early prevention
  • Make essential family planning
  • Create happy memories
  • Focus on things that truly matter

Care Team

People with Lewy Body Dementia often require a cross-disciplinary care team including: 

  • A neurologist specializing in Alzheimer’s
  • A neurologist specializing in Parkinson’s
  • A psychiatrist for behavior problems
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