MRI-based Alzheimer's disease-resemblance atrophy index in the detection of preclinical and prodromal Alzheimer's disease

Aging (Albany NY). 2021 May 25;13(10):13496-13514. doi: 10.18632/aging.203082. Epub 2021 May 25.

Abstract

Alzheimer's Disease-resemblance atrophy index (AD-RAI) is an MRI-based machine learning derived biomarker that was developed to reflect the characteristic brain atrophy associated with AD. Recent study showed that AD-RAI (≥0.5) had the best performance in predicting conversion from mild cognitive impairment (MCI) to dementia and from cognitively unimpaired (CU) to MCI. We aimed to validate the performance of AD-RAI in detecting preclinical and prodromal AD. We recruited 128 subjects (MCI=50, CU=78) from two cohorts: CU-SEEDS and ADNI. Amyloid (A+) and tau (T+) status were confirmed by PET (11C-PIB, 18F-T807) or CSF analysis. We investigated the performance of AD-RAI in detecting preclinical and prodromal AD (i.e. A+T+) among MCI and CU subjects and compared its performance with that of hippocampal measures. AD-RAI achieved the best metrics among all subjects (sensitivity 0.74, specificity 0.91, accuracy 85.94%) and among MCI subjects (sensitivity 0.92, specificity 0.81, accuracy 86.00%) in detecting A+T+ subjects over other measures. Among CU subjects, AD-RAI yielded the best specificity (0.95) and accuracy (85.90%) over other measures, while hippocampal volume achieved a higher sensitivity (0.73) than AD-RAI (0.47) in detecting preclinical AD. These results showed the potential of AD-RAI in the detection of early AD, in particular at the prodromal stage.

Keywords: MRI; amyloid and tau PET; preclinical Alzheimer’s disease; prodromal Alzheimer's disease; volumetric segmentation tool.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Alzheimer Disease / diagnosis*
  • Alzheimer Disease / diagnostic imaging*
  • Alzheimer Disease / pathology
  • Atrophy
  • Cognitive Dysfunction / complications
  • Cognitive Dysfunction / diagnostic imaging
  • Cohort Studies
  • Female
  • Hippocampus / pathology
  • Humans
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Prodromal Symptoms*
  • Temporal Lobe / pathology