Does informant‐based reporting of cognitive symptoms predict amyloid positivity on positron emission tomography?

Abstract

Abstract Introduction Researchers are searching for clinical instruments to predict amyloid positivity for disease classification. Informant‐based reports could detect disease status. This study compares subjective memory complaints captured by informant‐based reports between positron emission tomography (PET)–positive and PET‐negative patients and hypothesizes that amyloid PET positivity associates with increased informant‐based cognitive complaints. Methods Ninety‐eight amnestic mild cognitive impairment or mild dementia subjects were studied. Subjective report was captured by the informant‐driven Alzheimer's Questionnaire (AQ) administered before PET. Differences in demographics and AQ score by diagnostic status and amyloid status were measured, and a receiver‐operating characteristic curve was calculated. Results Sixty‐five mild cognitive impairment/Alzheimer's disease amyloid PET‐positive and 33 amyloid PET‐negative subjects were included. AQ was significantly higher (12.51 ± 4.95) for amyloid PET‐positive subjects (9.06 ± 3.65; P = .001). Conclusions Amyloid PET‐positive subjects with Alzheimer's disease or mild cognitive impairment have more informant‐based reports of cognitive decline, indicating utility for a brief informant measure.

Keywords

• Amyloid PET
• Informant‐based reporting
• Alzheimer's disease
• Dementia
• Disease classification