Machine learning reveals the most important psychological and social variables predicting the differential diagnosis of rheumatic and musculoskeletal diseases.

There is an ongoing debate about the importance and the extent to which psychological and psychopathological factors, adverse childhood experiences, and socio-demographic characteristics are associated with the development of certain types of rheumatic disease. With the aim of contributing to knowledge on the subject, the present study uses machine learning modeling to determine the importance of 20 psychological and social variables in predicting two classes of rheumatic disease: inflammatory rheumatic and musculoskeletal diseases (RMD) (rheumatoid arthritis = RA, spondyloarthritis = SA, and Sjögren's syndrome = SS) versus non-inflammatory RMD, namely fibromyalgia = FM). A total of 165 French women with FM, RA, SA, and SS completed an inventory of personality traits, a psychopathology diagnosis questionnaire, and a fatigue/pain questionnaire. They also answered questions about adverse childhood experiences and socio-demographic characteristics. Random forest and logistic regression machine learning algorithms were used for data analysis. The main findings suggest that mistreatment during childhood ((MDA = 10.22), the agreeableness personality trait (MDA = 3.39), and somatic disorder (MDA = 3.25) are the main psychological and social predictors of the type of rheumatic disease diagnosed. The first two predictors (OR = 18.92 and OR = 6.11) are also more strongly associated with FM than with RA-SA-SS. Overall, adverse childhood experiences seem relatively more important than personality traits, psychopathological or demographic variables. The results of this study suggest that traumatic childhood experiences may lead to psychopathological disorders in adulthood, which in turn might underlie, at least in part, the development of FM. Since there are no imaging or biological markers of FM, the present findings contribute to the scientific literature offering information to help patients with FM understand their pathology. They may also provide physicians with more diagnostic information.

A Comparative Study of Fibromyalgia, Rheumatoid Arthritis, Spondyloarthritis, and Sjögren's Syndrome; Impact of the Disease on Quality of Life, Psychological Adjustment, and Use of Coping Strategies.

BACKGROUND: Fibromyalgia, rheumatoid arthritis, spondyloarthritis, and Sjögren's syndrome are chronic rheumatic diseases with very different clinical characteristics, but which share symptoms such as pain and fatigue. The aim of the study was to examine the impact of the disease on psychological adaptation in fibromyalgia compared with other rheumatic diseases (rheumatoid arthritis, spondyloarthritis, and Sjögren's syndrome). METHODS: In a multicenter study, 165 women with rheumatic diseases (48 with fibromyalgia, 47 with rheumatoid arthritis, 47 with spondyloarthritis, 23 with Sjögren's syndrome) completed the General Health Questionnaire-28 (emotional distress), Fatigue Severity Scale (fatigue), Fibromyalgia Impact Questionnaire (impact of the disease), Coping Strategies Questionnaire (coping), and Mini International Neuropsychiatric Interview (comorbidity with DSM IV axis-I disorders). We used the Kruskal-Wallis test, Mann-Whitney U test, and chi2 test to compare comorbid anxiety and depressive disorders and to compare the impact of the disease on patients' mental well-being and daily life and adjustment (coping strategies). RESULTS: Anxiety and depressive disorders were more common in fibromyalgia patients; they had higher scores on impact of the disease, physical symptoms, pain, and fatigue than rheumatoid arthritis patients and reported more fatigue than patients with spondyloarthritis. Overall, they used more maladaptive coping strategies (less use of distancing from pain than patients with rheumatoid arthritis and spondyloarthritis, less use of ignoring pain sensations, and more use of catastrophizing than those with rheumatoid arthritis). No differences were found between fibromyalgia and Sjögren's syndrome on impact and adjustment. CONCLUSIONS: Compared with other rheumatic diseases, fibromyalgia has a greater impact on daily life; patients have more difficulty adjusting to the disease and generally use poorer strategies to cope with pain.

Comparison of the Big Five personality traits in fibromyalgia and other rheumatic diseases.

INTRODUCTION: 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. METHODS: 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. RESULTS AND DISCUSSION: 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.