The emPHasis-10 health-related quality of life (HRQoL) measure, a short 10-field questionnaire that assesses symptom burden in pulmonary arterial hypertension (PAH), is an effective, independent prognostic tool that can stratify patients with PAH based on mortality risk, according to study results in the European Respiratory Journal.
This study included patients with idiopathic PAH (n=994) or connective tissue disease (CTD)-PAH (n=751) and ≥1 emPHasis-10 score recorded between 2014 and 2018 at 6 PH referral centers in the United Kingdom. The investigators assessed anonymized demographic, hemodynamic, spirometric, exercise, emPHasis-10, and mortality data.
Incident patients with a PAH diagnosis from 2014 onward were required to have an emPHasis-10 score at diagnosis, whereas the first available emPHasis-10 score was used for analysis in prevalent patients diagnosed before 2014. Follow-up data included data from the first visit between 3 months and 12 months following the baseline emPHasis-10 score. Overall, the first emPHasis-10 score was considered the baseline score.
The majority of patients were women (73%), and approximately one-third (35%) of patients were incident patients and naive to treatment at time of the baseline emPHasis-10 score. Patients with CTD-PAH had a higher median emPHasis-10 score vs patients with IPAH (30 vs 28, respectively; P =.001).
In the correlation analysis with clinical parameters, there were moderate correlations (P <.0001 for all) between the emPHasis-10 scores and the 6-minute walk distance (r=-0.546), incremental shuttle walking distance (r=-0.504), and World Health Organization (WHO) functional class (FC) (r=0.497). There were significant differences (P <.0001 for all) between the scores in each WHO FC. The WHO FC 1, 2, 3, and 4 scores were 3, 19, 31, and 40, respectively.
A total of 674 (39%) patients died during the course of the study, and 240 (14%) died within a 1-year period of the baseline emPHasis-10 score. EmPHasis-10 scores of 0 to 16 classified incident patients with a 1-year mortality of 5%, 17 to 33 identified incident patients with a 1-year mortality of 10%, and scores of 34 to 50 identified incident patients with a 1-year mortality of 23%.
Patients in WHO FC 3 who were in the low- to intermediate emPHasis-10 risk groups had significantly better survival vs patients in the high-risk emPHasis-10 group, both for 1-year survival (90% vs 67%, respectively) and 3-year survival (81% vs 56%; P <.01). Patients with improved emPHasis-10 scores at follow up also had significantly improved exercise capacity (P <.0001).
A multivariate model that included emPHasis-10 score plus age, sex, CTD-PAH rather than idiopathic PAH, WHO FC, mean right atrial pressure, and cardiac index, the emPHasis-10 score was an independent predictor of survival outcome (hazard ratio, 1.565; P <.0001).
Study limitations included the lack of data on other measures of clinical deterioration, the study’s retrospective nature, and the lack of data on treatments patients were taking during the study period.
While this study demonstrated that improvements in the emPHasis-10 score correlates with exercise capacity improvements, the researchers concluded that “further work to determine the minimal clinically important difference is required.”
Lewis RA, Armstrong I, Bergbaum C, et al. EmPHasis-10 health-related quality of life score predicts outcomes in patients with idiopathic and connective tissue disease-associated pulmonary arterial hypertension: results from a UK multi-centre study [published online July 6, 2020]. Eur Respir J. doi:10.1183/13993003.00124-2020