Perioperative vascular events are common, particularly in patients undergoing vascular procedures. Although there are ways to identify high-risk patients, preventive measures are limited. Beta blocker therapy is one pharmacologic method that has had moderate efficacy in reducing risk. Lipid-lowering agents have anti-inflammatory effects and other plaque stabilizing properties. Lindenauer and colleagues studied whether lipid-lowering agents reduce mortality from myocardial infarction in patients undergoing major noncardiac surgery.
The retrospective cohort study included noncardiac surgery patients 18 years or older. The authors collected data on surgery type, comorbidities, and concomitant medications. Patients were divided into two groups—those who received lipid-lowering agents perioperatively (by day 3 of their hospital stay) and those who received the drugs late in their hospital stay or not at all. Patients in the treated group were further categorized as receiving statin or nonstatin therapy.
The analysis included 780,591 patients (77,082 in the treated group). About one fourth of treated patients had ischemic heart disease. Treated patients were likely to be white men, have higher revised cardiac index scores, and have more comorbidities compared with untreated and late-treated patients. The treated group also was more likely to have undergone orthopedic or vascular procedures and received beta blocker therapy and thromboembolism prevention measures. After matching treated and untreated patients, the authors found that 1,595 (2.18 percent) of the treated patients died, compared with 4,158 patients (3.15 percent) in the untreated and late-treated groups. The adjusted odds ratio for mortality favoring lipid-lowering agents was 0.62, and the number needed to treat was 85, but varied depending on cardiac risk. Statin and nonstatin users had a slightly lower mortality rate (2.09 versus 2.50 percent, respectively) compared with untreated or late-treated patients.
The authors conclude that patients undergoing major noncardiac surgery who are given lipid-lowering agents perioperatively have a 1 percent absolute reduction in mortality, representing a 38 percent decreased risk for in-hospital mortality compared with untreated or late-treated patients. The authors caution that lipid-lowering agents are not administered routinely early in a hospital stay. Therefore, lipid-lowering therapy in this study likely represents a resumption of ongoing outpatient therapy, and it is not known when lipid-lowering therapy should be initiated to achieve the effects noted in this study. This is an observational study, and the authors suggest that perioperative lipid-lowering therapy may be a marker for other aspects of care that lower mortality risk in surgery patients.