OBJECTIVE: To identify determinants of an inferior quality of life (QoL) 10 years after coronary artery bypass grafting (CABG). SETTING: Sahlgrenska University Hospital, Göteborg, Sweden. PARTICIPANTS: All patients from Western Sweden who underwent CABG between 1988 and 1991 without simultaneous valve surgery and no previous CABG. MAIN OUTCOME MEASURES: Questionnaires for evaluating QoL 10 years after the operation. Three different instruments were used: The Nottingham health profile (NHP), the psychological general wellbeing index (PGWI), and the Physical Activity Score (PAS). RESULTS: 2000 patients underwent CABG, of whom 633 died during 10 years of follow-up. Information on QoL at 10 years was available in 976 patients (71% of survivors). A history of diabetes and chronic obstructive pulmonary disease were the two independent predictors for an inferior QoL with all three instruments. Furthermore, there were three predictors of an inferior QoL with two of the instruments: high age, female sex and a history of hypertension. A number of factors predicted an inferior QoL with one of the instruments. These were the duration of angina pectoris and functional class prior to CABG, renal dysfunction, a history of cerebrovascular disease, obesity, height, duration of respirator treatment and requirement of inotropic drugs postoperatively. In addition, when introducing preoperative QoL into the model a low QoL before surgery was a strong independent predictor also of an inferior QoL 10 years after CABG. CONCLUSION: Variables independently predictive of an impaired QoL 10 years after CABG, irrespective of the instrument used, were an impaired QoL prior to surgery, chronic obstructive pulmonary disease and a history of diabetes. However, other factors reflecting gender, the previous history as well as postoperative complications were also associated with the QoL 10 years later in at least one of these instruments.