Longitudinal analysis of psychometric properties of the Seattle Angina Questionnaire among patients who underwent coronary artery bypass grafting in Serbia.

BACKGROUND: The psychometric properties of Seattle Angina Questionnaire (SAQ) have not been assessed longitudinally among people who underwent coronary artery bypass grafting (CABG). The purpose of this study was to examine psychometric characteristics of the SAQ in Serbian language in a cohort of patients who underwent CABG. METHODS: Study participants were recruited at the Department of Preoperative Patient Preparation, Clinic of Cardiac Surgery, Institute for Cardiovascular Diseases "Dedinje" (Belgrade, Serbia) from July 1, 2021 to December 31, 2023. The SAQ was administered at four time points: just before having CABG, 1, 6 and 12 months post-CABG. Also, the general health-related quality of life questionnaire Short Form-36 (SF-36) and Depression, Anxiety and Stress Scale-21 (DASS-21) were administered. Clinical parameters were retrieved from medical records. RESULTS: The study cohort included 192 participants (80.2% male, on average 64.5 ± 11.0 years old). Most α coefficients were good (> 0.70) or acceptable (> 0.60). Based on the correlations with clinical parameters, the criterion validity was good. Correlations with the SF-36 and depression and anxiety scores supported convergent and divergent validity, respectively. Based on the confirmatory factor analysis, the construct validity of the SAQ varied before and after CABG with regards to the ability to participate in high intensity activities and the angina occurrence, which was in line with the expected effect of CABG to free patients from angina, prolong survival and improve quality of life. CONCLUSIONS: The SAQ in Serbian has good psychometric properties. However, the SAQ domains of Angina frequency and Quality of life were most applicable in the first month post-CABG, while Physical limitations domain was most applicable at 6 months and 12 months post-CABG.