Pulmonary arterial hypertension in a multi-ethnic Asian population: Characteristics, survival and mortality predictors from a 14-year follow-up study.

Background and objective Pulmonary arterial hypertension (PAH) is a rare and fatal disease. Data from Asia are lacking compared with the West. We aim to describe disease characteristics in an ethnically diverse South-East Asian population and assess predictors for survival. Methods We consecutively enrolled patients with PAH referred to our pulmonary hypertension specialty centre from January 2003 to December 2016. Baseline characteristics and survival were analysed. Based on a forward predictor selection procedure, a multi-level structural equation model was applied to identify predictors associated with mortality. Results Out of 148 patients enrolled, 77% were females and mean age was 50.8 +/- 15.9 years. Racial distribution was consistent with our population census. The most common aetiologies were congenital heart disease-associated PAH (35.8%), idiopathic PAH (29.7%) and then connective tissue disease-associated PAH (24.3%). Most patients presented in World Health Organization (WHO) Functional Class (FC) II (48.6%), followed by FC III (28.8%). Majority of patients (54.1%) were on phosphodiesterase type 5 (PDE5) inhibitor monotherapy. Survival rates were 85.8% at the end of the first year, 70.9% at 3 years, 66.9% at 5 years, 61.5% at 7 years and 55.4% at 10 years. The Registry to Evaluate Early And Long-term PAH Disease Management (REVEAL) score (RS) was found to be the best predictor of mortality. A score > 6 was identified as a cut-off. Other predictors include mean right atrial pressure, heart rate, aetiology, age and N-terminal pro-brain natriuretic peptide. Conclusion In this first registry study from a South-East Asian population, our survival rates are comparable with other national registries. The RS is validated in our population to be a good predictor of mortality.