Background Pulmonary hypertension (PHT) has been reported between 0.5 and 14% in systemic lupus erythematosus (SLE), but some studies have suggested that a mild degree of PHT may be more common. Only a few studies have been carried out in caucasian using an algorithm for systematic evaluation with confirmation by right heart catheterization (RHC).
Objectives To assess the prevalence, etiology and risk factors for PHT in a monocentric SLE cohort.
Methods Prospective cross-sectional study of 158 SLE patients (ACR 1997 criteria). Resting doppler echocardiographic (dEcho), diffusing capacity for carbon monoxide (DLCO), NT-proBNP and Borg scale (for dyspnea) was performed in all patients. An exercise test (ET) was conducted in selected patients. We confirm PHT using RHC in the case of sPAP ≥45 mmHg (dEcho) or a +ET (>20mmHg increase in PAPs), excluding patients with obvious cardiac disease. A mean pulmonary pressure >20 mm Hg was accepted as PHT. Cumulative clinical characteristics were collected and damage (SLICC/ACR/DI) (SDI) and severity (Katz index) (IGK) were calculated.
Results Mean age: 45 (±12.9) years,94.3% females. Mean SLE duration: 14 (±8.0) years; mean SDI:1.1 (±1.6), IGK: 3.3 (±2.25), smokers any time: 37.2%. 21 patients (13.4%) had dyspnea at the evaluation time. 11 patients (6.9%) were found to have any degree of PAH. Etiologic classification (Dana Point 2008): 3 patients have left cardiac disease and the diagnosis was echocardiographic-based (sPAP>35mmHg), 1 patient had resting and 3 had postcapillary PAH on ET, a total of 7 patients in group 2. 1 patient had thromboembolic d. (group 4). 3 patients (2.5%) had precapillary PAH related with SLE (group 1), two of them had been previously diagnosed. Other conditions associated with PAH were not found. All 11 patients (100%) with PAH had dyspnea vs. 10 of 146 (6.8%) without PAH (p<0.001). PAH patients had more impaired DLCO when comparing with patients without PHT: 59% (±14%) vs. 68% (±15%) (p=0.048). 54% of PAH patients vs 4.1% of controls had Nt-proBNP >395, (p=0.000). Difference in medium Nt-proBNP (8685±663 vs. 191±578), p=0.000 (U Mann-Whitney) was also statistically significant. As expected, cardiac disease was more prevalent among PAH patients: 27.3 vs. 6.8%, p=0.05. There were no differences in SLE clinical characteristics between SLE patients with vs. without PHT.
Conclusions Our data confirms the low prevalence of precapillary PHT in SLE. We found a clear preponderance of cardiac etiology, mainly detected using exercise testing. A HTP screening program based on echocardiography, Nt-proBNP and DLCO not seem to be cost-effective and should be restricted to SLE patients with unexplained dyspnea.
Disclosure of Interest None Declared