Abstract
Background Pulmonary embolism (PE) is life threatening but evidence assessing risk factors of PE in systemic lupus erythematosus (SLE) is scarce. This study was conducted to explore the characteristics and risk factors of PE in SLE patients.
Methods Using the Hospital Information System of Peking Union Medical College Hospital, we conducted a case-control study in SLE patients complicated with PE (SLE-PE) and age-, sex-, and entry-time-matched control group (SLE-non-PE). Clinical and laboratory data were collected. We explored the risk factors of SLE-PE using multivariate logistic regression analyses.
Results A total of 90 patients were confirmed with PE from 6994 SLE patients. The annual incidence was 1.29% (95% CI: 1.15% to 1.42%), higher than that in general in-patients (0.347% and 95% CI: 0.34% to 0.354%). The overall incidence of PE in male SLE patients (1.86% and 95% CI: 1.40% to 2.32%) was higher than that in female SLE patients (1.21% and 95% CI: 1.07% to 1.35%). 257 contemporaneous SLE patients without PE were enrolled as control cohorts. In the SLE-PE group, the majority were female (74/90; 82.2%), with a mean duration of SLE before PE 3.04±2.16 years, and a high mortality rate of 8.9%. Multivariate analysis revealed that duration of SLE course <1.5years (OR 3.501(1.801–6.804), p<0.001), lupus nephritis (OR 2.692(1.328–5.457), p =0.006), hypoalbuminemia (OR 2.819(1.272–6.244), p=0.011), high hsCRP (OR 3.163(1.499–6.675), p=0.003), aPL positive (OR 10.262(4.691–22.447), p <0.001) and glucocorticoids, highest dose (OR 1.001(1–1.002), p=0.068) were significant independent risk factors of PE in SLE patients. Use of hydroxychloroquine (OR 0.291(0.139–0.608), p =0.001) was a protective factor of PE in SLE patients.
Conclusions This study provides general population-based evidence that SLE patients have an increased risk of PE. Increased vigilance in preventing this serious, but preventable complication, especially within months after SLE diagnosis is recommended.
