Specific changes in personality profiles may represent early symptoms of Alzheimer's disease (AD). Knowledge about relationship between personality changes and biomarkers of cerebral pathology can contribute to early diagnosis of AD.

To investigate to what extent the personality changes predict the cerebral AD pathology.

To describe the relationship between the personality changes and pathological cerebro-spinal fluid (CSF) biomarkers.

One hundred and ten subjects, of whom 57 patients with mild cognitive impairment (MCI), 9 subjects with mild dementia, and 44 healthy controls had an extensive medical and neuropsychological examination as well as lumbar puncture to evaluate concentrations of CSF biomarkers of AD pathology [amyloid-β1-42 (Aβ1-42), phosphorylated tau (ptau-181), and total-tau (tau)]. The proxies of the participants completed the Revised NEO Personality Inventory (NEO-PI-R) to assess subjects’ personality at the time being and 5 years retrospectively.

In a hierarchical multivariate regression analysis, including age, gender, education, Mini Mental State Examination (MMSE), and APOEe4 status, lower Aβ1-42 concentrations in CSF were associated with increasing neuroticism, and decreasing extraversion and conscientiousness. Decreasing extraversion, openness to experience and conscientiousness were associated with higher tau/Aβ1-42 ratio, and higher ptau-181/Aβ1-42 ratio was related to decreasing extraversion. Personality changes in the domain of agreeableness did not yield any significant effect as a predictor on any of CSF biomarkers.

Our findings suggest that early and specific changes in personality traits are associated with cerebral AD pathology, in particular with amyloid pathology, and may serve as clinical signs to consider when evaluating MCI and mild dementia.

The authors have not supplied their declaration of competing interest.