Abstract Details

Title Dissecting the Neurodegenerative Causes of Rapidly Progressive Dementia: An Autopsy Study

Topic Aging and Dementia

Presentation(s) S20 - Aging and Dementia 2 (2:36 PM-2:48 PM)

Poster/Presentation
Number 009

Background Most series exploring the causes of RPD rely on clinical diagnoses, with limited pathological confirmation. This approach may underestimate the contributions of Alzheimer disease and related dementias to RPD, recognizing challenges associated with extrapolating clinical phenotypes to neuropathological diagnoses. A clearer understanding of the neuropathological causes of RPD is needed to inform the diagnosis and treatment of patients.

Objective To determine the neuropathological causes of rapidly progressive dementia (RPD) in a neurodegenerative brain bank.

Design/Methods Patients with disease duration <4.0 years (symptom-onset to death-due-to-dementia) were identified within the Mayo Clinic neurodegenerative brain bank (1998-2020). Available clinical records were reviewed, and details extracted including demographics, family history, dominant symptoms/signs at onset, and common comorbidities (depression, psychoses, sleep disturbance). Neuropathological diagnoses were assigned following standard protocols.

Results 310/8586 (3.6%) cases met RPD criteria. Relative to typically progressive cases, prion disease most commonly presented as RPD (74%, 32/43), followed by progressive supranuclear palsy/corticobasal degeneration (PSP/CBD: 7.5%, 142/1894), other frontotemporal lobar degeneration (FTLD: 5.7%, 32/561), Lewy body disease (LBD: 4.1%, 49/1202), and Alzheimer disease (AD: 1.8%, 48/2687). Average age-at-symptom onset was 69.5±10.4 years. Patients with rapidly progressive AD were older than others (p<0.01), except LBD. Patients with FTLD were younger than others (p<0.05), except prion disease. Average disease duration was 2.9±1.0 years: prion diseases had the most rapid disease course (1.6±1.3 years). Comorbid cerebrovascular disease (25.5%), and clinically symptomatic depression (41.3%), psychoses (37.1%) and sleep disturbances (39.4%) were common across groups. Only psychosis was associated with shorter disease duration (β=-0.31 years, CI95% [-0.53, -0.082]; controlling for age-at-symptom onset).

Conclusions Rapidly progressive forms of neurodegenerative diseases accounted for 3.6% of cases in this neurodegenerative brain bank. Although prion disease commonly presented as RPD, atypical presentations of more prevalent neurodegenerative diseases accounted for most cases. Atypical (rapidly progressive) variants of typical neurodegenerative diseases warrant consideration in clinical practice.

Authors/Disclosures
Evelyn Lazar, MD (JFK Medical Center) PRESENTER	Dr. Lazar has nothing to disclose.
	No disclosure on file
Shanu Roemer	Shanu Roemer has nothing to disclose.
Neill R. Graff-Radford, MD, FAAN (Mayo Clinic Jacksonville)	The institution of Dr. Graff-Radford has received research support from Biogen. The institution of Dr. Graff-Radford has received research support from Lilly. The institution of Dr. Graff-Radford has received research support from Novartis. The institution of Dr. Graff-Radford has received research support from AbbVie. Dr. Graff-Radford has received publishing royalties from a publication relating to health care.
Dennis W. Dickson, MD (Mayo Clinic)	Dr. Dickson has nothing to disclose.
Gregory S. Day, MD, MSc, FAAN (Mayo Clinic)	Dr. Day has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Parabon Nanolabs. The institution of Dr. Day has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Eli Lilly. Dr. Day has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Arialys Therapeutics. Dr. Day has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Ionis. Dr. Day has received personal compensation in the range of $500-$4,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for DynaMed (EBSCO Health). Dr. Day has stock in ANI Pharmaceuticals. The institution of Dr. Day has received research support from National Institutes of Health / NIA. The institution of Dr. Day has received research support from Chan Zuckerberg Initiative. The institution of Dr. Day has received research support from Alzheimer's Association. The institution of Dr. Day has received research support from National Institutes of Health / NINDS. The institution of Dr. Day has received research support from Horizon Therapeutics. The institution of Dr. Day has received research support from AVID Radiopharmaceuticals. Dr. Day has received personal compensation in the range of $500-$4,999 for serving as a Presenter at Annual Meeting (CME) with American Academy of Neurology. Dr. Day has received personal compensation in the range of $500-$4,999 for serving as a Content Development (CME) with PeerView, Inc. Dr. Day has received personal compensation in the range of $5,000-$9,999 for serving as a Content Development (CME) with Continuing Education, Inc. Dr. Day has a non-compensated relationship as a Clinical Director with AntiNMDA Receptor Encephalitis Foundation that is relevant to AAN interests or activities.