OBJECTIVE: To investigate personality traits in patients with Alzheimer disease, 
compared with mentally healthy control subjects. We compared both current 
personality characteristics using structured interviews as well as current and 
previous personality traits as assessed by proxies.
METHOD: Fifty-four patients with mild Alzheimer disease and 64 control subjects 
described their personality traits using the Structured Interview for the 
Five-Factor Model. Family members filled in the Revised NEO Personality 
Inventory, Form R, to evaluate their proxies' current personality traits, 
compared with 5 years before the estimated beginning of Alzheimer disease or 5 
years before the control subjects.
RESULTS: After controlling for age, the Alzheimer disease group presented 
significantly higher scores than normal control subjects on current neuroticism, 
and significantly lower scores on current extraversion, openness, and 
conscientiousness, while no significant difference was observed on 
agreeableness. A similar profile, though less accentuated, was observed when 
considering personality traits as the patients' proxies remembered them. 
Diachronic personality assessment showed again significant differences between 
the 2 groups for the same 4 domains, with important personality changes only for 
the Alzheimer disease group.
CONCLUSIONS: Group comparison and retrospective personality evaluation are 
convergent. Significant personality changes follow a specific trend in patients 
with Alzheimer disease and contrast with the stability generally observed in 
mentally healthy people in their personality profile throughout their lives. 
Whether or not the personality assessment 5 years before the current status 
corresponds to an early sign of Alzheimer disease or real premorbid personality 
differences in people who later develop Alzheimer disease requires longitudinal 
studies.