# Towards optimizing the diagnosis of Lewy body dementia: Lessons from the NACC

## TL;DR

This study shows that Lewy body dementia is often misdiagnosed as Alzheimer's disease, especially in women with memory-related symptoms.

## Contribution

The study identifies patterns in misdiagnosis of LBD using autopsy data and clinical features.

## Key findings

- Less than half of LBD cases were correctly diagnosed before death.
- Alzheimer's disease was the most frequent misdiagnosis for LBD cases.
- Misdiagnosed cases were more likely to be female and have memory-related symptoms.

## Abstract

The diverse presentations and co‐pathologies of Lewy body dementia (LBD) present a diagnostic challenge. Utilizing the National Alzheimer's Coordinating Center (NACC) dataset, this study aimed to evaluate the concordance of premorbid diagnoses of LBD in individuals with autopsy‐confirmed neocortical Lewy body disease.

Demographics, clinical and neuropsychological presentations, Lewy body pathology, and Alzheimer's disease (AD) co‐pathology were related to clinical diagnosis.

Diagnosis of LBD had high specificity but low sensitivity, with fewer than half of autopsy‐confirmed cases having received an LBD diagnosis. AD was the most common misdiagnosis. Participants diagnosed with AD were more likely to be female, to have a more amnestic phenotype, and to harbor a higher burden of AD co‐pathology, and were less likely to have documented clinical features characteristic of LBD.

These results highlight the need to improve LBD diagnosis in research and clinical settings, a need that emerging biomarkers may help address.

Less than half of cases with neocortical Lewy bodies were diagnosed with Lewy body dementia (LBD)Alzheimer's disease (AD) was the most common misdiagnosisCases misdiagnosed were more likely to be femaleCases diagnosed with AD presented with a more amnestic phenotypeCases diagnosed with AD had more AD co‐pathology

Less than half of cases with neocortical Lewy bodies were diagnosed with Lewy body dementia (LBD)

Alzheimer's disease (AD) was the most common misdiagnosis

Cases misdiagnosed were more likely to be female

Cases diagnosed with AD presented with a more amnestic phenotype

Cases diagnosed with AD had more AD co‐pathology