Absolute risk of cognitive impairment by Alzheimer's Disease amyloid stages

Music City Center 

Despite advances in Alzheimer's disease (AD) research, limited information exists regarding the absolute risk of mild cognitive impairment (MCI) in cognitively unimpaired (CU) individuals with abnormal AD biomarkers, particularly when accounting for competing risks of death. We included 5,858 participants from the Mayo Clinic Study of Aging (MCSA) to evaluate AD amyloid stage as a predictor of clinical progression to MCI or dementia. The data includes long-term follow-up information on death and dementia beyond active study participation, which mitigates potential bias due to dropout. We predicted 10-year and lifetime risks of MCI and dementia, accounting for the competing risks of death, given amyloid PET stages, sex, APOE4 status, and baseline age. Results are based on a hidden Markov model. AD amyloid staging based on amyloid PET Centiloid values was the strongest predictor of lifetime risk for MCI or for dementia. Higher Centiloid levels amplified age effects on the risk of MCI, whereas for dementia, amyloid stage effects surpassed age effects. For 10-year risk, age was the dominant factor, whereas for lifetime risk, amyloid stages had a greater influence.

Hidden Markov Models

Alzheimer's Disease

Absolute Risk 

Section on Statistics in Imaging