Fibromyalgia (FM) was frequently observed in patients with rheumatoid arthritis (RA). We aimed to evaluate the differences in psychiatric comorbidities and life adversities between patients with RA+FM (SFM) and people with primary FM (PFM). In a cross-sectional, observational study, patients with PFM and SFM underwent a structured interview for the lifetime diagnosis of major depression (MDD), panic (PD) and post-traumatic stress disorder (PTSD) and were assessed for childhood/adulthood adversities and FM-related symptoms severity. Thirty patients with PFM and forty with SFM were recruited. The univariate analysis showed that the lifetime rates of MDD were significantly higher in PFM vs SFM (76.7 % and 40% respectively, p <0.003), as well as the rates of PD (50 % and 15% respectively, p <0.003), whereas there was no difference in PTSD rates. The rates of sexual abuse and physical neglect were significantly higher in PFM patients vs SFM patients (p<0.005 and p<0.023). Life events occurring before FM onset were different in PFM and SFM groups. In the logistic regression model, lifetime PD and physical neglect remain independent risk factors for PFM. PFM and SFM differ in psychiatric comorbidities and environmental adversities, suggesting that common pathogenesis may develop through different pathways. This article is protected by copyright. All rights reserved.This article is protected by copyright. All rights reserved.