BACKGROUND-: Health status is a key outcome for comparing treatments, particularly when mortality does not differ significantly. METHODS AND RESULTS-: Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) randomized 2368 patients with type 2 diabetes mellitus and stable ischemic heart disease to (1) prompt revascularization versus medical therapy and (2) insulin sensitization versus insulin provision. Randomization was stratified by the intended method of revascularization, coronary artery bypass graft surgery or percutaneous coronary intervention. The Duke Activity Status Index and RAND Energy, Health Distress, and Self-Rated Health scales were assessed at study entry and annually thereafter; linear mixed models were used to evaluate the effect of randomized treatment on these measures. Health status improved significantly from baseline to 1 year (P<0.001) in each randomized treatment group. Compared with medical therapy, prompt revascularization was associated with significantly greater improvements in Duke Activity Status Index (1.32 points; P<0.001), Energy (1.36 points; P=0.02), and Self-rated Health (1.77 points; P=0.007) but not Health Distress (-0.47; P=0.46). These treatment effects were largely maintained over 4 years of follow-up. The effect of revascularization on the Duke Activity Status Index was significantly larger in the subgroup of patients intended for coronary artery bypass graft surgery compared with the subgroup intended for percutaneous coronary intervention. Health status did not differ significantly on any of the 4 measures between the insulin provision and insulin sensitization strategies. CONCLUSIONS-: Prompt coronary revascularization was associated with small yet statistically significant improvements in health status compared with initial medical therapy among patients with diabetes mellitus and stable ischemic heart disease. © 2010 American Heart Association, Inc.