Plasma Biomarkers and Clinical Indicators for Identifying Mild Cognitive Impairment in Older Adults With Psychiatric Disorders

Background Mild Cognitive Impairment (MCI) and Mild Behavioral Impairment (MBI) can be prodromal stages of neurodegenerative disease associated with plasma biomarkers of tau pathology and neuroaxonal damage. However, in psychiatric populations, the relationship between MCI, MBI and these plasma biomarkers remains unclear. Objective This study examined the association of MCI with plasma biomarkers of neurodegeneration (phosphorylated tau217 [p-tau217] and neurofilament light chain [NfL]), metabolic alterations, psychiatric disorder features, and MBI in older adults receiving psychiatric treatment. Methods Fifty-one non-demented patients ≥60 years, referred for mood or anxiety disorders, were enrolled and classified based on cognitive performance as MCI (n = 20) or non-MCI (n = 31). Assessments included psychiatric, cognitive, functional, and plasma biomarker measures. Results MCI patients exhibited higher p-tau217 ( P = .003) and NfL ( P = .042) levels, lower cognitive scores ( P < .001), and a trend toward reduced functioning ( P = .074). MCI was also associated with later onset of psychiatric symptoms ( P = .033) and greater prevalence of MBI ( P < .001). Logistic regression identified plasma NfL as a marker of MCI ( P < .05) in this sample. Conclusion Our findings suggest that integrating cognitive, psychiatric, and biomarker assessments may improve early detection of dementia risk.