Systemic sclerosis (SSc) is associated with interstitial lung disease (ILD) and pulmonary hypertension (PH). This study was undertaken to determine the prevalence, characteristics, treatment, and outcomes of PH in a cohort of patients with SSc-associated ILD.
Patients with SSc-associated ILD on high-resolution computed tomography (HRCT) were included in a prospective observational cohort. Patients were screened for PH based on a standardized screening algorithm and underwent right-sided heart catheterization (RHC) if indicated. PH classification was based on hemodynamic findings and the extent of ILD on HRCT. Summary statistics and survival using the Kaplan-Meier method were calculated.
Of the 93 patients with SSc-associated ILD included in the study, 76% were women and 65.6% had diffuse cutaneous SSc. The mean age was 54.9 years, and the mean SSc disease duration was 8 years. Twenty-nine patients (31.2%) had RHC-proven PH; of those 29 patients, 24.1% had PAH, 55.2% had World Health Organization (WHO) Group III PH, 34.5% had WHO Group III PH with pulmonary vascular resistance >3.0 Wood units, 48.3% had a PH diagnosis within 7 years of SSc onset, 82.8% received therapy for ILD, and 82.8% received therapy for PAH. The survival rate 3 years after SSc-associated ILD diagnosis for all patients was 97%. The survival rate 3 years after PH diagnosis for those with SSc-associated ILD and PH was 91%.
In a large cohort of patients with SSc-associated ILD, a significant proportion of patients had coexisting PH, which often occurs early after SSc diagnosis. Most patients were treated with ILD and PAH therapies, and survival was good. Patients with SSc-associated ILD should be evaluated for coexisting PH.