Background:

Failure to resume perioperative statins after high–risk or vascular surgery is known to increase the risk of postoperative cardiac events. The effect of statin withdrawal on outcomes after moderate risk surgery is unknown. We performed a retrospective cohort study to understand this phenomenon.

Methods:

443 patients undergoing major (duration at least 2.5 hours) head and neck cancer surgery at the University of Michigan between 2002–2005 comprised the study cohort. Preoperative statin users were identified and postoperative statin use was recorded based on electronic pharmacy records. Statin withdrawal was considered to have occurred when statin treatment was not resumed within 4 days of surgery. The primary endpoint was a composite of 30–day death, myocardial infarction, unstable angina, stroke or congestive heart failure. Bivariate comparisons were made using Students t–test for continuous data and chi–square tests for categorical data. Multivariate comparisons were performed using logistic regression, controlling for demographics, co–morbidites, cancer stage, severity and treatment, preoperative risk, intra–operative events and postoperative factors. All statistical tests were two–tailed with P <0.05 being statistically significant. STATA MP/SE was used for statistical modeling.

Results:

Of 443 patients, 66 were chronic statin users. Statin users exhibited significant differences compared to non–statin users on bivariate testing (Table 1). At 30–days, 51 patients (11.5%) experienced the primary endpoint of which 39 (75%) were chronic statin users who had their statin withheld postoperatively. Mean withdrawal was 8.2 days. On multivariable logistic regression analysis, failure to resume postoperative statins within four days was independently associated with the development of 30–day complications (OR 2.27, 95% CI 1.52–3.08, P <0.001).

Conclusions:

Withholding chronic statin treatment after moderate risk surgery is associated with increased risk of death, myocardial infarction, stroke and congestive heart failure. These effects may relate to an “inflammatory rebound,” though the design of the present study precludes mechanistic insights. Hospitalists should remain vigilant about postoperative resumption of statins to prevent adverse cardiac outcomes.

Table 1Significant difference Between Statin Users and Non Users