Associations of personality traits and work-related stress with positive somatic symptom disorder screening – A cross-sectional study

BACKGROUND: Empirical evidence on psychological factors associated with somatic symptom disorder (SSD) is scarce so far, but could provide a better understanding of the psychological embeddedness of SSD. The current study targeted this research gap. METHODS: This cross-sectional study included 1536 participants of an inpatient psychosomatic unit between 2018 and 2024. A set of different self-report questionnaires was applied to evaluate SSD, depression and anxiety, narcissism, alexithymia, overcommitment, effort-reward imbalance (ERI), and burnout. A hierarchical multivariable binary logistic regression, applying a multiple imputation (MI) model considering missing data and a complete case model, was used to analyse associations between positive SSD screening and these psychological factors. Complementary analyses were conducted to further assess associations with the self-report questionnaires' subscales. RESULTS: 547 (35.6%) participants indicated a diagnosis of SSD. In the final MI model, alexithymia (OR 1.02, 95% CI 1.01-1.03), narcissism (1.06, 1.03-1.08), and ERI (1.76, 1.10-2.82) were significantly associated with a higher risk for positive SSD screening. Complementary analyses revealed significant associations with the alexithymia subscales difficulty identifying feelings (1.08, 1.01-1.15) and difficulty describing feelings (0.96, 0.92-0.99), the narcissism subscales threatened self (0.97, 0.94-0.99) and hypochondriac self (1.25, 1.15-1.35), and the burnout subscales emotional exhaustion (1.07, 1.01-1.13) and cynicism (0.94, 0.90-0.98). CONCLUSIONS: Positive SSD screening was common in the observed population. Future studies may strive to unravel the mechanisms linking SSD potentially with alexithymia, narcissism, ERI, and burnout. A deeper understanding of the relationship between these psychological factors' subscales and SSD might be a key element in this endeavour.