Identifying coronary artery bypass grafting patients at high risk for adverse long-term prognosis using serial health-related quality of life assessments

Abstract

Background: Patients who undergo coronary artery bypass grafting (CABG) are known to be at a significant risk of experiencing long-term adverse events, emphasizing the importance of regular assessments. Evaluating health-related quality of life (HRQoL) serves as a direct method to gauge prognosis. Our objective is to ascertain the prognostic significance of consecutive HRQoL assessments using the Physical Component Summary (PCS) and Mental Component Summary (MCS) derived from the Short-Form 36 (SF-36) health survey in CABG patients. Methods: The study population consisted of 433 patients who underwent isolated elective CABG at Fuwai Hospital between 2012 and 2013. SF-36 assessments were conducted during both the hospitalization period and follow-up. The primary endpoint of the study was all-cause mortality, while the secondary outcome was a composite measure including death, myocardial infarction, stroke, and repeat revascularization. We assessed the relationships between the PCS and MCS at baseline, as well as their changes during the first 6 months after the surgery (referred to as ΔPCS and ΔMCS, respectively), and the observed outcomes. Results: The patients were followed for an average of 6.28 years, during which 35 individuals (35/433, 8.1%) died. After adjusting for clinical variables, it was observed that baseline MCS scores (hazard ratio [HR] for a 1-standard deviation [SD] decrease, 1.57; 95% confidence interval [CI], 1.07–2.30) and ΔMCS (HR for a 1-SD decrease, 1.67; 95% CI, 1.09–2.56) were associated with all-cause mortality. However, baseline PCS scores and ΔPCS did not exhibit a significant relationship with all-cause mortality. Notably, there was a dose-response relationship observed between ΔMCS and the likelihood of all-cause mortality (HRs for the 2nd, 3rd and 4th quartiles compared to the 1st quartile, 0.33, 0.45 and 0.11, respectively). Conclusions: Baseline MCS and changes in MCS were independent predictors for long-term mortality of CABG. Better mental health status and recovery indicated better prognosis.