Mild Behavioural Impairment and Everyday Functioning in Cognitively Unimpaired Older Adults: Evidence From the CAN-PROTECT Study

Abstract

Background: Recognizing early clinical signs of dementia is key to optimizing emerging therapies, including monoclonal antibodies. Mild behavioural impairment (MBI) characterizes later-life emergent and persistent nropsychiatric symptoms linked to greater dementia risk, representing a behavioural manifestation of the underlying neurodegenerative disease for some. The association of MBI with functional ability may therefore reveal subtle functional decline as an additional early risk marker in cognitively unimpaired (CU) older adults.

Methods: Baseline data from 1714 CU participants from the CAN-PROTECT study were analyzed. MBI was assessed using the MBI Checklist (MBI-C) (continuous and dichotomized, MBI+ ≥8). Functional ability was assessed using the SAGEA scale capturing instrumental and basic activities. Negative binomial models examined associations between MBI and function, adjusting for demographics, cognition, and physical/sensory limitations.

Results: Higher MBI-C scores (count ratio [CR] = 1.07; 95%CI: 1.06-1.07) and MBI+ status (CR = 2.64; 95%CI: 2.36-2.95) were associated with greater global and domain-specific functional impairments.

Conclusion: Findings highlight the importance of assessing both behavioural and functional changes in CU adults to identify at-risk individuals for timely interventions.