REVEAL Score performance in patients with WHO Group 2 pulmonary hypertension

Abstract

Abstract Introduction Pulmonary hypertension (PH) secondary to left heart disease, also known as World Health Organization (WHO) Group-2 pulmonary hypertension (WHO-2 PH) is the most common form of PH worldwide. Various risk prediction scores have been derived and validated for other forms of PH, including the REVEAL 2.0 and REVEAL Lite 2 scores. However, whether these scores accurately predict outcomes in patients with WHO-2 PH remains to be investigated. Methods We retrospectively analyzed patients referred to the PH Clinic at the Univ. of Cincinnati from 2016-2022. Only patients with WHO-2 PH were studied. REVEAL 2.0 and REVEAL lite 2 scores were calculated for all patients at the first outpatient visit (OV). Longitudinal assessment was only available for the REVEAL lite 2 score up to 36-48 months. Patients were stratified as low, intermediate, and high-risk and Kaplan-Meier and Cox proportional hazards statistics were used to assess survival based on risk stratification. Concordance index was calculated to evaluate the performance of each independent score in discriminating survivors vs. non-survivors at one year from the first OV (OV-1). Results Total of 214 patients were studied. Mean age was 64.7 years (13.4 SD), and 66.4 % were female. Patients demographic and clinical characteristics are shown in Table 1. At the OV-1, 15% of patients were stratified as low-risk, 27% as intermediate, and 57% as high-risk (Figure 1). Estimated survival (95% confidence intervals [CIs]) at 1 year was 100% [CI 99-100], 96% [CI 91-100], and 89% [CI 84-95] for low, intermediate, and high-risk patients, respectively. Median survival for high-risk patients was 4.6 years [CI 3.33-NA]. Only 98 patients were alive or had sufficient data to calculate REVEAL Lite 2 score. After OV-1, 13% (n=13) of patients changed to a low-risk strata, 57% (n=56) remained at the same level and 30% (n=29) changed to a high-risk strata. Total of 28% (n=68) of patients died within study period. Cox proportional hazards analysis showed that patients classified as high-risk based on REVEAL 2.0 (³9) or REVEAL Lite 2 (³8) had a statistically higher risk of death (HR 5.32 [CI 2.27-12.46], p<0.001 and HR 4.09 [CI 1.62-10.27], p= <0.01 compared to low-risk patients. The C-indices for REVEAL 2.0 and REVEAL lite 2 were 0.67 (p<0.001) and 0.65 (p<0.001). We found no difference in the risk of death between patients stratified as intermediated when compared to low-risk using either score. Conclusions In this single center, retrospective study, the REVEAL 2.0 and REVEAL Lite 2 risk prediction scores were able to differentiate patients at low vs high-risk of death. However, the scores failed to predict mortality in patients categorized at intermediate risk. Importantly, most of our patient population fell within this category at first visit and frequently remained at intermediate risk during the study period. Revisions to these scores are warranted to account for differences in this patient population.Table 1Figure 1