Neurofibrillary pathology in Alzheimer disease with Lewy bodies: two subgroups

Arch Neurol. 1999 Feb;56(2):203-8. doi: 10.1001/archneur.56.2.203.

Abstract

Background: While NFT frequency is reportedly reduced in AD+DLB, we often encounter abundant neocortical NFTs in such cases and decided to investigate this discrepancy.

Objective: To compare neurofibrillary tangle (NFT) frequency in Alzheimer disease with concomitant dementia with Lewy bodies (AD+DLB) with NFT frequency in "pure" AD.

Methods: Neurofibrillary tangle frequency, as well as regional staging of neurofibrillary degeneration modified from Braak, was scored in 160 autopsy cases of primary dementia (80 AD+DLB cases and 80 pure AD cases).

Results: Neurofibrillary tangle and modified Braak scores were lower in AD+DLB, as reported previously. Yet, neocortical NFT scores assumed markedly different patterns in the 2 groups (P = .001). In pure AD, NFT scores of "frequent" were predominant: more cases exhibited frequent than moderate or sparse NFTs. In AD+DLB, the distribution of NFT scores was bimodal: NFTs were either frequent or few to absent. Neocortical NFT scores in the AD+DLB group tended to parallel the severity of other types of tau cytopathology (neuropil threads and tau-positive plaque neurites).

Conclusions: Cases of AD+DLB may be divided into 2 subgroups based on the extent of neocortical neurofibrillary pathology. These findings could have implications for disease pathogenesis and treatment.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / pathology*
  • Female
  • Frontal Lobe / pathology
  • Humans
  • Immunohistochemistry
  • Lewy Bodies / pathology*
  • Male
  • Middle Aged
  • Neurofibrillary Tangles / pathology*
  • Parietal Lobe / pathology
  • Temporal Lobe / pathology