The personality of patients with fibromyalgia is still under debate. Some studies found high neuroticism associated with low extraversion, while others found that these traits do not differ from the normal population. Personality factors intervene in the emotional regulation and modulation of pain. The aim of the study was to determine the personality traits of patients with fibromyalgia compared to other rheumatic diseases.

In a multicentric study, women with fibromyalgia, rheumatoid arthritis, spondyloarthritis or Sjögren's syndrome were asked to complete the Big Five Inventory, which encompasses five main personality dimensions, namely (1) extraversion vs. introversion, (2) agreeableness vs. antagonism, (3) conscientiousness vs. impulsivity, (4) neuroticism vs. emotional stability, and (5) openness vs. closed-mindedness. Variance analysis (Student's t-test and ANOVA with post-hoc comparisons or Bonferroni correction) was performed. We also conducted hierarchical and non-hierarchical cluster analyses.

Participants were 163 women with fibromyalgia (n=48), rheumatoid arthritis (n=46), spondyloarthritis (n=46) and Sjögren's syndrome (n=23). The mean age was 47.18years (±10.81years, range 21 to 65). Patients with fibromyalgia had higher scores on agreeableness (F(3, 159)=3.39, P<0.05), neuroticism (F(3, 159)=3.79, P<0.05) and openness (F(3, 159)=4.32, P<0.01) than those with other rheumatic diseases. This study highlights the specificity of personality in fibromyalgia. It also underlines the protective role of personality traits: in the fibromyalgia group, high neuroticism and low conscientiousness (high impulsivity) were associated with a high level of chronic pain.