The Mediating Role of Negative Affect in the Relationship Between Anger Rumination and Somatic Symptoms.
BACKGROUND A high prevalence of somatisation is associated with a strong impairment of quality of life. Recent research suggests common underlying mechanism of central sensitisation in functional syndromes and chronic pain, with emotion regulation (ER) processes closely linked to somatic symptoms. This study examines the relationship between negative affect (NA) and anger rumination (AR) and its influence on somatisation. METHODS Five hundred seven individuals participated (mean age = 34.60 ± 13.22 years; 380 women). They completed the Patient Health Questionnaire, Negative Affect Scale, and Displaced Aggression Questionnaire. A cross-sectional multivariate factorial relational design was used. Descriptive, multiple linear regression, and mediation analyses were conducted on the total and sex-separated samples. RESULTS Data analysis revealed a significant positive relationship between NA and AR (r = 0.55, p < 0.01), and both were significantly associated with somatisation (rumination: r = 0.37, p < 0.01; NA: r = 0.54, p < 0.01). Simple linear regressions confirmed that higher levels of NA and AR individually predicted increased somatic symptoms in both sexes. However, multiple regression analyses revealed that the effect of AR on somatisation was reduced in women and became non-significant in men when accounting for NA. Mediation analysis showed a significant indirect effect of AR on somatisation through negative affect (B = 0.005, 95% bootstrap confidence interval [0.004, 0.006]), accounting for 62.5% of the total effect. The mediation pattern was replicated in both women (indirect effect B = 0.005, 95% confidence interval [0.004, 0.007]) and men (indirect effect B = 0.004, 95% confidence interval [0.002, 0.006]). These findings indicated that part of the effect of AR on somatisation occurred under the influence of NA. CONCLUSIONS NA and AR were associated with increased somatic symptoms. These findings suggest the benefit of developing interventions that encourage the use of functional ER strategies. These can help to reduce NA, which in a prolonged form can constitute a vulnerability for organisms, especially in those people with a tendency to somatise.