Predictors of Health-Related Quality of Life After Coronary Artery Bypass Grafting: A Systematic Review

Background: Coronary artery bypass grafting (CABG) is the most common adult cardiac surgical procedure worldwide. Although survival and graft patency are well characterised, health-related quality of life (HRQoL) is increasingly recognised as a patient-centred outcome that may be modifiable. Existing syntheses have summarised global HRQoL change after CABG but have not consistently focused on the patient-, surgery- and recovery-level factors associated with that change. Methods: PubMed/MEDLINE, Embase, Cochrane CENTRAL and CINAHL were searched from 1 January 2010 to 31 March 2025. Eligible studies were primary investigations (prospective or retrospective cohort, cross-sectional analytical, or randomised controlled trial) of adults (≥18 years) undergoing isolated CABG that reported HRQoL with a validated multidimensional instrument and assessed at least one candidate factor. Two reviewers independently screened records, extracted data and assessed risk of bias using the Newcastle–Ottawa Scale for observational studies and the Cochrane Risk of Bias 2 tool for randomised trials. Certainty of evidence was rated using the GRADE approach as adapted for prognostic-factor questions. Owing to heterogeneity in instruments, factor definitions and follow-up, results were synthesised narratively; no meta-analysis was performed. Results: Of 1220 records identified, six studies met the inclusion criteria, three prospective cohorts, two cross-sectional analytical studies and one randomised controlled trial, together contributing analysable HRQoL data on 1271 patients. Follow-up ranged from the end of post-operative cardiac rehabilitation to 10 years. Four different instruments were used: the SF-36 in three studies, the SF-36 with the SF-12 in one, the SF-12v2 in one and the disease-specific MacNew questionnaire in one. Risk of bias was low in two cohort studies and moderate in the remaining three observational studies, and low overall for the randomised trial. No factor was examined by more than five of the six studies, and most were reported by only one or two; findings are therefore described by the number of supporting studies rather than as consistent. Diabetes mellitus and post-operative complications were each independently associated with poorer physical HRQoL in two studies. Female sex, older age, lower pre-operative HRQoL, repeat percutaneous coronary intervention, heart failure or dyspnoea, social support, cardiac self-efficacy, marital status and unemployment were each supported by a single study. Depressive symptoms were not confirmed as an independent factor in the only study modelling them separately, and cardiac rehabilitation could not be evaluated because every patient received it wherever it was delivered. The sole randomised comparison showed that exercise-based prehabilitation improved pre-operative functional capacity and quality of life, but by less than the minimal clinically important difference and with no significant post-operative effect. Conclusions: Factors associated with HRQoL after CABG cluster into non-modifiable demographic and comorbidity factors, potentially modifiable psychosocial and behavioural factors, and recovery-related factors emerging post-operatively. The evidence base is nevertheless small, clinically and methodologically heterogeneous, and almost entirely observational. The factors identified are candidate targets requiring confirmation in prospective studies with pre-operative measurement and, thereafter, in randomised trials; they are not established causal determinants. Persistent heterogeneity of HRQoL instruments and factor definitions argues for standardised reporting in future studies of cardiac surgical recovery.