Association between fibromyalgia and psychiatric disorders in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that may affect many organs, with musculoskeletal symptoms being the most common. Fibromyalgia (FM) is frequent in SLE patients. Psychiatric disorders such as anxiety and depression are also present in many SLE patients. The aim of our study is to determine the relationship between FM and psychiatric symptoms (PS), both anxious (AS) and depressive (DS), and its impact on health status in SLE patients.

In a total of 84 SLE patients we studied the presence of both FM and PS using specific questionnaires (Hamilton). We also evaluated health status and SLE disease activity by both the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and serological markers. Patients performed the Short Form 12 (SF-12) questionnaire as a quality of life measure. Qualitative variables were compared using Pearson's chi-square test and Fisher's exact test, and Student's t-test was used for quantitative variables. The Mann-Whitney U-test was applied if a normal distribution was not observed.

Thirty patients were diagnosed with FM (35.7%), 16 had clinical signs DS (19%) and 30 had clinical signs AS (35.7%). We found a statistically significant association between FM and AS (p<0.001), and between FM and DS (p<0.001). Higher SF-12 physical component and mental component scores were observed in FM group compared to non-FM group (p<0.001). We have not found any associations between SLE activity and FM and PS.

There is a high prevalence of FM in SLE patients, and a strong association with DS and AS. FM contributes to worsening health status in SLE patients. SLE activity has little or no impact either on psychiatric symptoms or FM.