Impact of lipid-lowering medications and low-density lipoprotein levels on 1-year clinical outcomes after coronary artery bypass grafting

Background: Studies investigating lipid-lowering medication (LLM) use and LDL levels in coronary artery bypass grafting patients are limited. Study design: The Veterans Affairs Randomized On/Off Bypass Trial's patient records were analyzed for LLM use and 1-year LDL levels. Mortality, acute MI (AMI), and repeat revascularization rates were compared at 1 year between patients with and without LLM at discharge. In addition, AMI, repeat revascularization, and graft patency were compared between patients that did and did not achieve a 1-year LDL target level of <100 mg/dL. Results: The LLM data were available for 86.4% (1,904 of 2,203) of patients. Rates of LLM use were 83.4% (1,316 of 1,577) at discharge and 90.0% (1,713 of 1,904) at 1 year. Patients discharged after coronary artery bypass grafting on LLMs had a significantly lower 1-year mortality rate (1.9% vs 5.4%; p < 0.01) than those not discharged on LLM, and 1-year AMI and repeat revascularization rates were not significantly different. Of the patients with 1-year LDL measurements, 69.4% (1,200 of 1,729) achieved an LDL target level of <100 mg/dL. No differences were seen in AMI, revascularization, or graft occlusion rates between patients who achieved target LDL levels and those who did not. Conclusions: Rates of LLM use among veterans post-coronary artery bypass grafting are high. Discharge on LLM might be associated with improved intermediate-term survival. Patients who achieved an LDL target of <100 mg/dL at 1-year did not experience improved 1-year clinical outcomes or graft patency. Longer-term follow-up might reveal differences in cardiac outcomes related to achievement of target LDL levels.