Retrospective validation of the REVEAL 2.0 Risk Score with the Australian and New Zealand Pulmonary Hypertension Registry Cohort.

Abstract

Pulmonary arterial hypertension (PAH) prognosis has improved with targeted therapies although the long-term outlook remains poor. Objective multi-parametric risk assessment is recommended to identify patients at risk of early morbidity and mortality, and for optimization of treatment. The REVEAL 2.0 Risk Score is a new model proposed for the follow-up of PAH patients but has not been externally validated. The REVEAL 2.0 Risk Score was applied to a mixed prevalent and incident cohort of PAH patients (n=1,011) from the Pulmonary Hypertension Society of Australia and New Zealand (PHSANZ) Registry. Kaplan-Meier (KM) survival was estimated for each REVEAL 2.0 Risk Score strata and for a broader three-category (low, intermediate, high-risk) model. Sensitivity analysis was performed on an incident-only cohort. The REVEAL 2.0 model effectively discriminated risk in the large external PHSANZ registry cohort, with c-statistic 0.74 (both for full 8-tier and three-category models). When applied to incident cases only, c-statistic was 0.73. The three-category REVEAL 2.0 model demonstrated robust separation of 12 and 60-months survival estimates (all risk categories comparisons p<0.001). Although the full 8-tier REVEAL 2.0 model separated low, intermediate and high-risk patients, survival estimates overlapped within some of the intermediate and high-risk strata. The REVEAL 2.0 risk score was validated in a large external cohort from the PHSANZ Registry. The REVEAL 2.0 model can be applied for risk assessment of PAH patients at follow-up. The simplified 3-category model may be preferred for clinical use and for future comparison with other prognostic models.