The Multifaceted Phenomenon of Anosognosia in Dementia and Its Relationship to Premorbid Personality Traits

OBJECTIVE: Anosognosia, the unawareness of a person's own neurological or psychiatric symptoms, is a common manifestation of dementia. Anosognosia may involve different cognitive or behavioral domains and may be influenced by factors such as premorbid personality traits. In this study, the authors investigated the relationship between premorbid personality traits and different anosognosia subtypes. Another objective was to assess the interrelationships among the anosognosia subtypes. METHODS: The authors evaluated individuals with mild cognitive impairment (MCI) and mild-to-moderate dementia. Anosognosia was evaluated by using differences in scores between questionnaires completed by the participants and by their informants (with positive indices indicating worse anosognosia). Several questionnaires were used to assess distinct cognitive domains. Premorbid personality traits were evaluated with the Big Five Inventory 2-short version. RESULTS: Data for 67 individuals with MCI or mild-to-moderate dementia were included. Agreeableness and the socioemotional anosognosia subtype were strongly and negatively correlated with each other (r=-0.627), and a strong positive correlation was detected between neuroticism and the behavioral anosognosia subtype (r=0.569) (both p<0.01, Bonferroni corrected). No significant correlation was observed between premorbid personality traits and functional, memory, and general cognition anosognosia subtypes. Correlations were moderate to strong for the functionality and memory (r=0.488) and socioemotional and behavioral (r=0.569) anosognosia subtypes (both p<0.01, Bonferroni corrected). CONCLUSIONS: The observed correlations of several anosognosia subtypes with predementia-onset personality traits and the absence of significant interrelationships among the anosognosia subtypes assessed suggest that cognitive-functional and behavioral-socioemotional anosognosias represent two relatively independent clusters, possibly driven by different neural and environmental mechanisms.