Mild behavioral impairment is associated with progression to Alzheimer's disease: A clinicopathological study.

Abstract

Mild behavioral impairment (MBI) is characterized by later-life emergence of neuropsychiatric symptoms. Investigating its relationship with progression to Alzheimer's disease (AD) would provide insight on its importance as a predictor of AD. Cognitively normal participants (N=11,372) from the National Alzheimer's Coordinating Center were stratified by MBI status, using the Neuropsychiatric Inventory-Questionnaire. We investigated whether MBI and its domains were predictors of progression to clinically-diagnosed AD. MBI as a predictor of progression to neuropathology-confirmed AD was also investigated in those with neuropathological data. Six percent (N=671) of participants progressed to AD. MBI (N=2765) was a significant predictor of progression to clinically-diagnosed (hazard ratio [HR] = 1.75) and neuropathology-confirmed AD (HR = 1.59). MBI domains were also associated with clinically-diagnosed AD, with psychosis having the greatest effect (HR = 6.49). These findings support the biological underpinnings of MBI, emphasizing the importance of later life behavioral changes in dementia detection and prognostication.