Clinical and neuropathological characteristics of hippocampal sclerosis: a community-based study.
BACKGROUND
Hippocampal sclerosis (HS) is a neuropathologic finding characterized by neuronal loss and gliosis in the CA-1 and subiculum of the hippocampus. Previous studies of HS have shown that this is a common postmortem finding in elderly subjects with dementia. However, these studies were from selected samples and therefore are not necessarily representative of patients seen in the general medical community.


OBJECTIVE
To examine the clinical and pathologic characteristics of HS in a community-based case series of dementia and to compare these characteristics with those observed in subjects with Alzheimer disease (AD) from the same study sample.


METHODS
One hundred thirty-four autopsy cases were available from a community-based registry of dementia. Sixteen cases (12%) had a postmortem diagnosis of HS. Thirty-two comparison control cases with a neuropathologic diagnosis of AD were selected from the same files. Each case of HS was reviewed for HS neuropathologic features, including severity, distribution, and additional pathologic processes. Blinded review of clinical characteristics for the HS and control groups was performed to assess risk factors.


RESULTS
There was a wide range of severity and distribution of HS lesions between cases and substantial variability in lesion severity and age within individual cases. Serial neuropsychologic and behavioral assessments revealed similar clinical features and rates of dementia progression between HS and AD groups. Of all neuropsychologic tests performed at enrollment, only enhanced performance on Trails A differentiated the HS from the AD group (64 seconds, 0 errors vs 114 seconds, 0.6 errors; P< or = .05). The number of AD cases with at least 1 apolipoprotein epsilon 4 allele was significantly greater than the HS cases (61% vs 31%; chi(2) = 3.81, P< or = .05). Although medical record review indicated higher frequencies of clinical stroke and neuroradiologic white matter abnormalities in the HS group, risk factors for vascular disease and neuropathologic evidence of cerebrovascular disease did not differ between the groups.


CONCLUSIONS
Our results suggest that HS is a frequent pathologic finding in community-based dementia. Individuals with HS have similar initial symptoms and rates of dementia progression to those with AD and therefore are frequently misclassified as having AD. Our clinical and pathologic findings suggest that HS has characteristics of a progressive disorder although the underlying cause remains elusive.
Leverenz
James B
JB
Veterans Affairs Northwest Network Mental Illness Research, Education, and Clinical Center, Veterans Affairs Puget Sound Health Care System, 1660 S Columbian Way, 116 MIRECC, Seattle, WA 98108, USA. leverenz@u.washington.edu
Agustin
Christina M
CM
Tsuang
Debby
D
Peskind
Elaine R
ER
Edland
Steven D
SD
Nochlin
David
D
DiGiacomo
Lillian
L
Bowen
James D
JD
McCormick
Wayne C
WC
Teri
Linda
L
Raskind
Murray A
MA
Kukull
Walter A
WA
Larson
Eric B
EB
D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000235:genetics / Q000473:pathology* / Q000523:psychology; D001057:Apolipoproteins E / Q000235:genetics; D003704:Dementia / Q000235:genetics / Q000473:pathology* / Q000523:psychology; D005260:Female; D005838:Genotype; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008297:Male; D008499:Medical Records; D009483:Neuropsychological Tests; D012042:Registries; D012189:Retrospective Studies; D012598:Sclerosis; D012720:Severity of Illness Index
D001057:Apolipoproteins E