Prevalence and risk factors for pulmonary arterial hypertension in patients with lupus.

OBJECTIVES Pulmonary arterial hypertension (PAH) is associated with rapid deterioration and poor prognosis in SLE, especially during pregnancy. The prevalence of PAH in SLE in non-tertiary centres is uncertain. This study aims to estimate the point prevalence of PAH and identify risk factors for PAH in a large cohort of SLE patients. METHODS A prospective cross-sectional study of 288 patients with SLE were recruited from lupus clinics in Birmingham, UK. Resting transthoracic echocardiography was performed to estimate the pulmonary artery pressures and to assess cardiac morphology and function. PAH was defined as systolic pulmonary artery pressure (sPAP) >30 mmHg. We assessed potential risk factors such as the presence of lung disease, respiratory muscle weakness, autoantibodies, smoking, RP and APS. RESULTS Of 288 patients who consented for participation, 283 patients were suitable for analysis. Twelve patients were found to have PAH with sPAP >30 mmHg. The range of sPAP in our PAH patients was 31-59 mmHg and three patients had sPAP >40 mmHg. The only significant risk factor for PAH was LAC (P = 0.005). CONCLUSIONS The point prevalence of PAH was 4.2% in our cohort of patients with SLE. Most of the PAH cases were found to be of mild severity (<40 mmHg). The significant association of LAC and presence of APS in PAH cases suggests that thrombosis may play an important role in PAH with SLE. This is important, as it is treatable.