The Survival Rate of Hospitalized Lupus Patients With Overlap Disease.

Objective Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease associated with a rate of mortality during hospitalization. On the other hand, SLE can be associated with other autoimmune diseases with different morbidity and mortality, so a combination of SLE and other autoimmune diseases, as overlap diseases, may increase the risk of morbidity and mortality. The aim of this study was to determine the survival rate of hospitalized SLE patients who also had other autoimmune diseases. Method We used a retrospective data collection from the inpatient files collected over the past 10 years in the Shariati Hospital, Rheumatology Department, Tehran University of Medical Sciences. Results We identified 219 patients with SLE who overlapped with other autoimmune diseases. Nearly 90% (n=197) were female patients. The mean age of patients was 37.9 years. The most common overlap autoimmune disease alongside SLE was anti-phospholipid syndrome (APS; n=99; 45.4%), followed by rheumatoid arthritis (RA) and scleroderma (n=29; 13.3% each). We had eight (3.7%) deaths in the hospitalized patients, of which six (75.0%) were female patients. The SLE patients who had overlap with APS, scleroderma, and RA died during hospitalization. The general survival rate of SLE patients with at least one autoimmune disease was around 75% (n=164), and the female patients had a better survival rate than the male patients (n=152; 77.0% and n=12; 75.0%, respectively). Infection was the main cause of mortality. Conclusion The general survival rate of SLE patients with at least one autoimmune disease was around 75%. Presence of overlap with APS, scleroderma and RA, and male gender worsened the survival rate.