Dementia with Lewy Bodies: More Than Just Memory Loss

A mysterious mind, a body in protest, and the search for answers.

The Second Most Common Dementia You've Probably Never Heard Of

Dementia with Lewy bodies is a complex brain disorder caused by the accumulation of abnormal protein deposits, called Lewy bodies, inside the brain's nerve cells. These deposits are primarily made of a misfolded protein called alpha-synuclein 2 7 . This clumping of alpha-synuclein disrupts normal cell communication and eventually leads to the death of brain cells.

1M+

Americans affected by DLB

2nd

Most common progressive dementia

α-syn

Key protein involved

Dr. Denise Compton, a geriatrics neuropsychologist, notes that DLB is "widely underdiagnosed," meaning many may be living with the condition without a correct diagnosis 1 .

DLB exists on a spectrum of what clinicians call "Lewy body disease," which also includes Parkinson's disease and Parkinson's disease dementia. The distinction often comes down to a timeline of symptoms: if cognitive symptoms appear before or within a year of movement problems, it's DLB; if movement problems come first and cognitive decline follows later, it's diagnosed as Parkinson's disease dementia 5 .

Lewy Body Disease Spectrum

Deciphering the Symptoms: More Than Just Memory Loss

While memory loss can occur in DLB, the most salient features often lie elsewhere. Clinicians look for a specific set of core and supportive symptoms to piece together the diagnostic puzzle 2 4 .

Core Symptoms
  • Fluctuating Cognition
    Dramatic variations in attention and alertness 5 7
  • Vivid Visual Hallucinations
    Detailed, well-formed visions of people or animals 1
  • REM Sleep Behavior Disorder (RBD)
    Physically acting out dreams, often violently 1
  • Spontaneous Parkinsonism
    Slow movement, rigid muscles, tremors 2 5
Supportive Features
Feature Category Specific Symptoms
Autonomic Dysfunction Constipation, dizziness upon standing, urinary incontinence 2 7
Neuropsychiatric Symptoms Apathy, anxiety, depression, delusions 4 7
Other Physical Signs Severe sensitivity to antipsychotic medications, frequent falls, loss of smell 2 5

Symptom Prevalence in DLB Patients

The Air Pollution Connection: A Groundbreaking Experiment

A landmark study from Johns Hopkins Medicine, published in September 2025, revealed for the first time a potential molecular connection between air pollution and an increased risk of developing Lewy body dementia 6 .

Human Data Analysis

Analysis of 56.5 million U.S. hospital admissions between 2000 and 2014, using ZIP code data to estimate long-term exposure to PM2.5.

Animal Model Exposure

Exposed different groups of mice to PM2.5 samples from China, Europe, and the U.S. every other day for up to 10 months.

Biophysical Analysis

Used advanced techniques to study structural changes, cell death, and alpha-synuclein clumps in mouse brains.

Increased Risk from PM2.5 Exposure
Key Findings from PM2.5 Exposure
Mouse Model Outcome After PM2.5 Exposure
Normal Mice Developed brain atrophy, cell death, and cognitive decline similar to DLB symptoms 6
Mice lacking alpha-synuclein Showed no significant brain changes 6
Mice with hA53T mutation Developed widespread abnormal alpha-synuclein after just 5 months 6

"This suggests that pollution may not only trigger the build-up of toxic proteins but also drive disease-related gene expression changes in the human brain," said Dr. Shizhong Han, a lead investigator on the study 6 .

The Scientist's Toolkit: Essential Reagents in DLB Research

Tool or Reagent Primary Function in DLB Research
Alpha-Synuclein Seed Amplification Assays (SAA) A breakthrough diagnostic tool that detects misfolded alpha-synuclein in cerebrospinal fluid 4
Thioflavin Dyes Fluorescent dyes used in SAAs that bind to aggregated proteins 4
Cholinesterase Inhibitors Frontline pharmacological treatment for cognitive decline in DLB 4
Monoclonal Antibodies Investigational antibody-based therapies designed to target protein aggregates 1 4
123I-MIBG Cardiac Scintigraphy Biomarker test that assesses autonomic nerve function 2

From the Lab to the Clinic: Treatment Today and Hope for Tomorrow

Current management of DLB is primarily symptomatic, as there are no approved treatments that can slow or stop the underlying disease progression 4 5 .

Current Management
Pharmacological Approaches
  • Cholinesterase inhibitors for cognitive and psychiatric symptoms 4
  • Careful management of movement symptoms
  • Avoiding antipsychotics due to severe sensitivity 5
Non-Pharmacological Strategies
  • Creating consistent routines
  • Fall prevention and safety measures
  • Comprehensive caregiver support 1
Promising Drug Trials
Neflamapimod (RewinD-LB trial) Phase 2
CT1812 (SHIMMER trial) Phase 2
Zervimesine Phase 2
Ambroxol & Memantine Repurposing Studies

Other global trials are exploring the repurposing of existing drugs 8 .

Clinical Trial Pipeline for DLB

Preclinical Research

Identification of targets and drug candidates

Phase 1 Trials

Safety and dosage studies in small groups

Phase 2 Trials

Efficacy and side effects (Neflamapimod, CT1812, Zervimesine)

Phase 3 Trials

Confirmatory studies in larger populations

Regulatory Approval

FDA and international agency review

A Future of Hope

The journey to understand Dementia with Lewy bodies is accelerating. Researchers are moving ever closer to unlocking the mysteries of this complex condition—from identifying potential environmental triggers like air pollution to developing sensitive diagnostic tests and targeted therapies.

Early Diagnosis

Improved biomarkers and detection methods

Targeted Therapies

Drugs addressing underlying pathology

Patient Support

Enhanced care and quality of life

"Our lives are absolutely more enriched," Susan says after James's participation in a clinical trial 9 . His story is a powerful testament to the dual value of research: it offers personal hope today while building a foundation of knowledge for a cure tomorrow.

For more information and support, please contact the Lewy Body Dementia Association (lbda.org) or the Alzheimer's Association (alz.org).

References