Comparison of the Seattle Angina Questionnaire With Daily Angina Diary in the TERISA Clinical Trial

Background-As new techniques emerge to quantify patients' health status, new opportunities are created to validate patient-reported outcome questionnaires. The Seattle Angina Questionnaire (SAQ), a widely used coronary artery disease-specific health status tool, has not been validated against daily records of angina frequency and sublingual nitroglycerin (SL NTG) use. Additional evidence supporting the validity of the SAQ could justify its broader use as an outcome for clinical studies designed to evaluate treatments that may improve patients' symptoms, function, and quality of life. Methods and Results-We used data from 917 patients with type 2 diabetes mellitus, coronary artery disease, and stable angina from the multinational Type 2 Diabetes Evaluation of Ranolazine in Subjects With Chronic Stable Angina (TERISA) trial. The number of angina episodes and SL NTG used were recorded and transmitted daily using an electronic diary. In cross-sectional analyses, there was a strong relationship between the 2 SAQ angina frequency questions (ie, frequency of angina and SL NTG use) and the corresponding diary responses, with correlation coefficients of -0.64 for angina frequency (95% confidence interval,-0.68 to -0.60) and -0.69 for SL NTG use (95% confidence interval, -0.73 to -0.66). Longitudinally, changes in SAQ angina frequency scores from day 1 to week 8 also correlated with changes in angina frequency (-0.42; 95% confidence interval, -0.48 to -0.30) and SL NTG use by diary (-0.38; 95% confidence interval, -0.43 to -0.32) over the corresponding time period. Correlations were similar when stratified by age, sex, or geography. Conclusions-In a multinational cohort of patients with stable angina, the SAQ angina frequency domain was significantly correlated, both cross sectionally and longitudinally, with daily diary entries of angina frequency and SL NTG use. These data further support the validity of the SAQ angina frequency domain across a broad spectrum of patients with stable angina.