The use of Event Related Potentials to predict amyloid PET status among patients from a memory disorders clinic
Myna Chadalavada, Anna Marin, Kylie A Schiloski, Cheongmin Suh, Prayerna Uppal, Rocco Palumbo, Andrew E Budson, Katherine W Turk- Psychiatry and Mental health
- Cellular and Molecular Neuroscience
- Geriatrics and Gerontology
- Neurology (clinical)
- Developmental Neuroscience
- Health Policy
- Epidemiology
Abstract
Background
Amyloid PET scans provide in vivo evidence of Alzheimer’s Disease (AD) however, due to high cost and limited insurance coverage, they are not available as part of standard clinical care. Event Related Potentials (ERPs) are inexpensive, and non‐invasive method to directly measure brain physiology that may allow an alternative method for detection of AD pathology.
Method
We investigated whether ERPs together with neuropsychological data are predictors of amyloid PET status in patients with memory complaints. Older veterans aged 50‐100 were recruited from a memory disorders clinic at VA Boston Healthcare System. Participants underwent a standard neuropsychological battery and an ERP auditory oddball protocol. Twenty‐eight patients had a positive amyloid PET scan, and thirty‐nine patients had a negative amyloid PET scan.
Results
Two neuropsychological measures (CERAD Delayed Recall and MMSE) were predictors of amyloid PET status. Increased P200 target amplitude (Figure 1B), and decreased P200 standard latency (Figure 1A) in patients with amyloid PET positive scan were found. ERP‐P200 amplitude in response to target tones and ERP‐P200 latency in response to standard tones were also predictors of amyloid PET status. The highest classification accuracy was obtained when combining CERAD Delayed Recall, MMSE and ERP‐P200 standard latency.
Conclusion
ERP‐P200, especially when combined with cognitive measures of delayed memory and overall cognitive function, was predictive of amyloid beta (Aβ) load in the brain of patients from a memory disorder clinic. Increased P200 amplitude, and decreased P200 latency in patients with amyloid PET positive scan might suggest hyperactivation of perceptual bottom‐up processes to compensate for AD‐related synaptic loss in the fronto‐parietal networks.