Background Pulmonary Arterial Hypertension (PAH) is a severe complication of Systemic Lupus Erythematosus (SLE). With more widely access of Right Heart Catheterization (RHC) as the gold standard, detection of PAH in SLE patients has been increased. However, poor prognosis of SLE related PAH emphasized the importance of early diagnosis and proper strategy of treatment.
Objectives Peking Union Medical College Hospital (PUMCH) started the registry of SLE-PAH since 2004, progressing as part of Chinese SLE Treatment And Research Group (CSTAR), a nationwide rheumatology database. We are presenting baseline characteristics to explore risk factors of PAH in Chinese patients with SLE.
Methods Patients with SLE who met definition of the WHO group I PAH were enrolled. PAH was confirmed by RHC, and enrollment started right after procedure performance. All patients were ruled out other underlying connective tissue diseases or other groups PAH. Important data including demographics, disease durations, SLE criteria, clinical manifestations, laboratory tests, functional class and hemodynamic parameters were recorded. Control cases are from CSTAR database. Risk factors were examined by univariate analysis and binary logistic regression analysis.
Results 79 SLE-PAH patients (35.0±8.5 yr; F/M 76/3) were enrolled from 2004 to 2014. PAH was developed in the 6th years of SLE course on average, and was initial manifestation in 25% patients. Shortness of breath was the most common primary complain for PAH (85%), followed by fatigue (32.9%), cough (20.3%), syncope (17.7%) and Raynaud phenomenon (17.7%). 60.9% of patients at registry were in New York Heart Association (NYHA) Functional Class (Fc) III or IV. Six-minute walk test was 408±108m. Mean pulmonary artery pressure, cardiac output, and pulmonary vascular resistance were 47±12mmHg, 2.5±0.8L/min, and 10.6±4.9mmHg/L/min/m2 respectively. 316 SLE-non PAH patients were selected from CSTAR database with adjustment for age and gender. Independent risk factors found in this case-control study include serositis (OR=2.002; 95%CI 1.175–3.413; P=0.013), antiphospholipids (OR=2.010; 95%CI 1.165–3.467; P=0.015), anti-Sm antibody (OR=3.481; 95%CI 2.039–5.940; P<0.001), anti-RNP antibody (OR=5.872; 95%CI 3.441–10.021; P<0.001) and anti-SSA antibody (OR=3.272; 95%CI 1.955–5.477; P<0.001), which are in accordance with previous studies.
Conclusions Our study is by far the largest catheter-based registry for SLE-PAH in CHINA. Shortness of breath is the most common but nonspecific symptom for PAH. PAH usually develop late during SLE course. Most SLE-PAH patients at diagnosis by RHC are in NYHA class III and IV. Risk factors for PAH in SLE patients are serositis, positivity of antiphospholipid, anti-Sm, anti-RNP and anti-SSA antibody.
Acknowledgements We would like to thank Dr Zhuang Tian and Dr Yongtai Liu from Cardiology Department of Peking Union Medical College Hospital for their work in right heart catheterization performance.
Disclosure of Interest None declared