Hippocampal Sclerosis in the Oldest Old: A Finnish Population-Based Study

J Alzheimers Dis. 2018;63(1):263-272. doi: 10.3233/JAD-171068.

Abstract

Background: There are only few population-based studies that have systemically investigated the prevalence of hippocampal sclerosis (HS) in the very old. The frequency of unilateral versus bilateral HS has been rarely studied.

Objective: We investigated the prevalence and laterality of HS and its association with other neurodegenerative and vascular pathologies in a population-based sample of very elderly. Furthermore, the concomitant presence of immunoreactivity for TDP-43, p62, and HPtau was studied.

Methods: The population-based Vantaa 85+ study includes all inhabitants of the city of Vantaa, who were >85 years in 1991 (n = 601). Neuropathological assessment was possible in 302 subjects. Severity of neuronal loss of CA sectors and subiculum was determined bilaterally by HE- staining. Immunohistochemistry performed using antibodies for TDP-43, p62, and HPtau.

Results: Neuronal loss and pathological changes in the hippocampus sector CA1 and subiculum were observed in 47 of the 302 individuals (16%), and 51% of these changes were bilateral. HS without comorbid neurodegenerative pathology was found in 1/47 subjects with HS (2%). Dementia (p < 0.001) and TDP-43 immunopositivity of the granular cell layer of the dentate fascia (p < 0.001) were strongly associated with HS. The CERAD score, immunopositivity for HPtau and p62 in the granular cell layer of the fascia dentate were also associated.

Conclusion: HS is prevalent (16%) in the oldest old population, but HS without any comorbid neurodegenerative pathology is rare. The high frequency of unilateral HS (49%) implied that bilateral sampling of hippocampi should be routine practice in neuropathological examination.

Keywords: Dementia; TDP-43; hippocampal sclerosis; hippocampal sclerosis without any comorbid neurodegenerative pathology; laterality; population-based; very old.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged, 80 and over
  • Aging / pathology*
  • Community Health Planning
  • DNA-Binding Proteins / metabolism
  • Female
  • Finland / epidemiology
  • Functional Laterality
  • Hippocampus / pathology*
  • Humans
  • Male
  • Neurodegenerative Diseases / epidemiology*
  • Neurodegenerative Diseases / pathology*
  • Sclerosis / epidemiology
  • Sequestosome-1 Protein / metabolism
  • tau Proteins / metabolism

Substances

  • DNA-Binding Proteins
  • SQSTM1 protein, human
  • Sequestosome-1 Protein
  • TARDBP protein, human
  • tau Proteins