Personality traits in people with multiple sclerosis: A systematic review and meta-analysis

Objective: Although numerous studies have investigated personality traits in people with multiple sclerosis (PwMS), a thorough systematic review and meta-analysis of this evidence has not been conducted. This review aimed to elucidate the personality profile of PwMS relative to healthy controls (HCs) and to assess the overall correlations between personality traits and mood, cognitive performances, fatigue, and physical function in PwMS. Methods: PubMed/MEDLINE, Scopus, Embase, and Web of Sciences were systematically searched up to 18 August 2024, to identify studies (1) comparing personality traits, including Agreeableness, Conscientiousness, Extraversion, Neuroticism, and Openness, between PwMS and HCs or (2) assessing the correlation between personality traits, anxiety, depression, cognition, fatigue, and physical function in PwMS. The pooled standardized mean differences (SMDs) or correlations were estimated. Results: Sixty-three studies on 8068 PwMS and 1588 HCs were included. PwMS exhibited different personality traits, notably higher Neuroticism, compared to HCs. Furthermore, Neuroticism showed the most significant pooled correlations with mood and fatigue, while Conscientiousness demonstrated the greatest pooled correlations with disability and cognitive performance in PwMS. The meta-analysis confirmed these findings, revealing that PwMS have higher Neuroticism (SMD = 0.35) than HCs. Additionally, higher Neuroticism was significantly linked to increased anxiety (r = 0.78), depression (r = 0.53), and fatigue (r = 0.35), and Conscientiousness was significantly correlated with decreased Expanded Disability Status Scale (EDSS) (r = -0.21) and Symbol Digit Modalities Test (SDMT) (r = 0.13). Conclusions: PwMS exhibited distinct personality traits compared to healthy individuals. Additionally, personality traits, particularly Neuroticism and Conscientiousness, had relationships with mood, cognitive performance, fatigue, and physical function of PwMS.