Lipid-Lowering Therapy and In-Hospital Mortality Following Major Noncardiac Surgery

Abstract

CONTEXT: Cardiovascular complications following major noncardiac surgery are an important source of perioperative morbidity and mortality. Although lipid-lowering medications are considered a key component in the primary and secondary prevention of cardiovascular disease, their potential benefit during the perioperative period is uncertain. OBJECTIVE: To examine the association between treatment with lipid-lowering medications and in-hospital mortality following major noncardiac surgery. DESIGN, SETTING, AND PATIENTS: A retrospective cohort study based on hospital discharge and pharmacy records of 780,591 patients aged 18 years or older who underwent major noncardiac surgery from January 1, 2000, to December 31, 2001, at any 1 of 329 hospitals throughout the United States. Only patients who survived through at least the second hospital day were included. Lipid-lowering therapy was defined as use during the first 2 hospital days. Propensity matching was used to adjust for numerous baseline differences. MAIN OUTCOME MEASURE: In-hospital mortality. RESULTS: Of the 780,591 patients, 77,082 patients (9.9%) received lipid-lowering therapy perioperatively and 23 100 (2.96%) died during the hospitalization. Treatment with lipid-lowering agents was associated with lower crude mortality (2.13% vs 3.05%, P<.001). In an analysis using matching by propensity score, 1595 patients (2.18%) treated with lipid-lowering medications died compared with 4158 patients (3.15%) who did not receive therapy or in whom treatment was initiated after the second day (P<.001). After adjusting for residual differences in the propensity matched groups using conditional logistic regression, risk of mortality remained lower among treated patients (adjusted odds ratio [OR], 0.62; 95% confidence interval [CI], 0.58-0.67). Based on this adjusted OR, the number needed to treat to prevent a postoperative death in the propensity matched cohort was 85 (95% CI, 77-98) and varied from 186 among patients at lowest risk to 30 among those with a revised cardiac risk index score of 4 or more. In a further analysis using the entire study cohort and adjusting for quintile of propensity, a significant effect of treatment persisted (adjusted OR, 0.71; 95% CI, 0.67-0.75). CONCLUSIONS: Treatment with lipid-lowering agents may reduce risk of death following major noncardiac surgery. Clinical trials are required to confirm this observation.