OBJECTIVE: To describe the limitation of physical activity and symptoms of chest pain and dyspnea before and after coronary artery bypass grafting (CABG) in relation to a history of diabetes. RESEARCH DESIGN AND METHODS: All patients in western Sweden in whom CABG was performed between 1988 and 1991 were asked to complete a questionnaire before 3 months and 2 years after the operation. The questionnaire evaluated limitation of physical activity and symptoms of chest pain and dyspnea. RESULTS: In all, 2,121 patients participated in the evaluation, of whom 13% had a history of diabetes. The overall 2-year mortality was 14% among patients with a history of diabetes and 6% among patients without such a history (P < 0.001). The proportion of patients with a limitation of physical activity caused by chest pain decreased from 76% before CABG to 19% 2 years after in diabetic patients (P < 0.001) and from 79 to 17% in nondiabetic patients (P < 0.001). The proportion of diabetic patients without dyspnea increased from 13% before to 31% 2 years after CABG (P < 0.001). The corresponding figures for nondiabetic patients were 12 and 43% (P < 0.001). Symptoms of angina pectoris were reported in 94% of diabetic patients before CABG versus 35% after 2 years (P < 0.001). Corresponding figures for nondiabetic patients were 93 and 29% (P < 0.001). Aggregate data confirmed differences between diabetic and nondiabetic patients, with more symptoms in the diabetic patients, particularly with regard to dyspnea. CONCLUSIONS: Mortality during 2 years of follow up was more than twice as high in diabetic than in nondiabetic patients. Limitation of physical activity, dyspnea, and angina pectoris improved markedly and similarly in diabetic and nondiabetic patients after CABG. Whereas limitation of physical activity and dyspnea was more frequent in diabetic than in nondiabetic patients, the occurrence of angina pectoris was more similar in the two groups.