Conversion of the Seattle Angina questionnaire into EQ-5D utilities for ischemic heart disease: A systematic review and catalog of the literature

Abstract

Background: There is a paucity of preference-based (utility) measures of health-related quality of life for patients with ischemic heart disease (IHD); in contrast, the Seattle Angina Questionnaire (SAQ) is a widely used descriptive measure. Our objective was to perform a systematic review of the literature to identify IHD studies reporting SAQ scores in order to apply a mapping algorithm to convert these to preference-based scores for secondary use in economic evaluations. Methods: Relevant articles were identified in MEDLINE (Ovid), EMBASE (Ovid), Cochrane Library (Wiley), HealthStar (Ovid), and PubMed from inception to 2012. We previously developed and validated a mapping algorithm that converts SAQ descriptive scores to European Quality of Life-5 Dimensions (EQ-5D) utility scores. In the current study, this mapping algorithm was used to estimate EQ-5D utility scores from SAQ scores. Results: Thirty-six studies met the inclusion criteria. The studies were categorized into three groups, ie, general IHD (n=13), acute coronary syndromes (n=4), and revascularization (n=19). EQ-5D scores for patients with general IHD were in the range of 0.605-0.843 at baseline, and increased to 0.649-0.877 post follow-up. EQ-5D scores for studies of patients with recent acute coronary syndromes increased from 0.706-0.796 at baseline to 0.795-0.942 post follow-up. The revascularization studies had EQ-5D scores in the range of 0.616-0.790 at baseline, and increased to 0.653-0.928 after treatment; studies that focused only on coronary artery bypass grafting increased from 0.643-0.788 at baseline to 0.653-0.928 after grafting, and studies that focused only on percutaneous coronary intervention increased in score from 0.616-0.790 at baseline to 0.668-0.897 after treatment. Conclusion: In this review, we provide a catalog of estimated health utility scores across a wide range of disease severity and following various interventions in patients with IHD. Our catalog of EQ-5D scores can be used in IHD-related economic evaluations. © 2014 Wijeysundera et al.