Chest
Volume 141, Issue 2, February 2012, Pages 354-362
Journal home page for Chest

Original Research
Pulmonary Vascular Disease
The REVEAL Registry Risk Score Calculator in Patients Newly Diagnosed With Pulmonary Arterial Hypertension

https://doi.org/10.1378/chest.11-0676Get rights and content

Background

In pulmonary arterial hypertension (PAH), survival predictions can be important for optimization of therapeutic strategies. The present study aimed to validate a quantitative algorithm for predicting survival derived from the Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL Registry) and develop a simplified calculator for everyday clinical use.

Methods

Prospectively collected data from patients with newly diagnosed (< 3 months) World Health Organization group I pulmonary hypertension enrolled in the REVEAL Registry were used to validate a predictive algorithm for 1-year survival. Model calibration was evaluated by comparing algorithm-predicted survival with observed Kaplan-Meier estimates for the overall validation cohort and for five risk groups. Similarly, the risk discriminators for the simplified calculator were compared with those of the quantitative algorithm.

Results

The validation cohort comprised 504 individuals with mean ± SD 6-min walk distance 308 ± 128 m, and 61.5% were functional class III. The proportion of patients surviving 1 year fell within the range predicted by the model (95.1%, 91.5%, 84.6%, 76.3%, and 58.2%, respectively) among patients in the low (predicted survival ≥ 95%), average (90% to < 95%), moderate (85% to < 90%), high (70% to < 85%), and very high (< 70%) risk strata. Predicted and observed 1-year survival were similar across risk stratum, and the c-index indicated good discrimination for both the full equation (0.726) and the simplified risk calculator (0.724).

Conclusions

The REVEAL Registry predictive algorithm and simplified risk score calculator are well calibrated and demonstrate good discriminatory ability in patients with newly or previously diagnosed PAH.

Trial registry

ClinicalTrials.gov; No.: NCT00370214; URL: www.clinicaltrials.gov

Section snippets

Materials and Methods

A comprehensive description of the design of the REVEAL Registry, including inclusion and exclusion criteria and statistical methods, has been published, as has a description of the 2,716 patients included in the model development cohort and the methods used to develop the predictive survival algorithm.4, 5 Variables independently associated with increased mortality in the multivariable survival model included a collection of etiologic factors and parameters that can be identified by physical

Results

The validation cohort comprised 504 individuals with newly diagnosed PAH who were enrolled between September 2007 and December 2009 and who met the traditional hemodynamic criteria (pulmonary capillary wedge pressure ≤ 15 mm Hg). The characteristics of these patients and of those in the model development cohort are shown in Table 1. At the time of enrollment, the mean age of patients in the validation cohort was 53 years, 74% were women, and 69% were white. Compared with the model development

Discussion

PAH is a comparatively rare condition, which has made it historically difficult to study. For this reason, large registry studies are useful in better defining the condition and for providing insight into factors that influence survival and prognosis. When compared with previous registry studies,8, 9, 10, 11, 12, 13, 14, 15 The REVEAL Registry is the largest and most comprehensive registry to date. Indeed, the size of the validation cohort—the subject of the present analysis—is as large as or

Acknowledgments

Author contributions: Dr Benza: contributed to the study design; collection, analysis, and interpretation of data; and drafting and critical review of the manuscript and has seen and approved the final version.

Dr Gomberg-Maitland: contributed to the study design; collection, analysis, and interpretation of data; and drafting and critical review of the manuscript and has seen and approved the final version.

Mr Miller: contributed to the study design; collection, analysis, and interpretation of

References (22)

  • S Suissa

    Immortal time bias in observational studies of drug effects

    Pharmacoepidemiol Drug Saf

    (2007)
  • Cited by (0)

    Funding/Support: Funding for the REVEAL Registry is provided by Actelion Pharmaceuticals US, Inc.

    Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (http://www.chestpubs.org/site/misc/reprints.xhtml).

    View full text