Fibromyalgia Prevalence and Related Factors in a Large Registry of Patients with Systemic Lupus Erythematosus.

The objective of this study is to determine the prevalence of fibromyalgia (FM) in systemic lupus erythematosus (SLE) patients and to study its relationship to depression and other SLE-related factors.A cross-sectional data analysis from the RELESSER-Transversal Spanish Registry, which includes SLE patients in a national multicentre retrospective charts review, was performed.patients who fulfilled ≥4 ACR 1997 SLE criteria. Main variables were disease duration, depression, sociodemographics, comorbidities, SLE activity symptoms, serological findings, therapies and different disease status indices. Statistical analyses included a descriptive, associative and logistic regression analyses. A literature review was performed.3,591 SLE patients were included, 90.1% women, 34.6 years of age at diagnosis (SD 14.6 years) and 93.1% Caucasians. FM prevalence was 6.2%. SLE patients with disease duration >5 years showed more FM than those with duration <5 years: 6.9% vs. 4.0%, respectively (p<0.05). SLE-FM patients showed higher prevalence of depression compared to non-FM-SLE patients: 53.1% vs. 14.6%, respectively (p<0.001). After adjusting by risk factors, the OR (CI) of suffering depression in FM-SLE patients was 6.779 (4.770-9.636), p<0.001. The OR of having secondary Sjögren's 2.447 (1.662-3.604), p<0.001, photosensitivity 2.184 (1.431-3.334), p<0.001, and oral ulcers 1.436 (1.005-2.051), p=0.047.Prevalence of FM in Caucasian SLE patients was high compared to the general population, and was significantly higher in those in later stages of disease. SLE patients with depression showed a strong risk of developing FM. Photosensitivity, oral ulcers and secondary Sjögren's were the only SLE-related factors associated with FM.