Statin use and neurologic morbidity after coronary artery bypass grafting: A cohort study

Effects of inflammation and oxidative stress on postoperative delirium in cardiac surgery

The past decade has witnessed unprecedented medical progress, which has translated into cardiac surgery being increasingly common and safe. However, complications such as postoperative delirium remain a major concern. Although the pathophysiological changes of delirium after cardiac surgery remain poorly understood, it is widely thought that inflammation and oxidative stress may be potential triggers of delirium. The development of delirium following cardiac surgery is associated with perioperative risk factors. Multiple interventions are being explored to prevent and treat delirium. Therefore, research on the potential role of biomarkers in delirium as well as identification of perioperative risk factors and pharmacological interventions are necessary to mitigate the development of delirium.

The Impact of Statins before High-Risk CABG on Postoperative Multiple Organ Function

Background

The purpose of this cohort study was to investigate the independent relationship between preoperative statin therapy (PST) and postoperative severe multiorgan failure, measured by the Sequential Organ Failure Assessment (SOFA) maximum greater than 11, in high-risk patients undergoing isolated coronary artery bypass grafting (CABG).

Methods

The present study is a perspective, single-center, cohort analysis enrolling high-risk patients undergoing CABG from Jan 1, 2018, to Dec 31, 2018, in Beijing Anzhen hospital.

Results

Among a total of 880 high-risk patients undergoing isolated CABG included in this study, 503 (57.2%) experienced statin therapy before CABG. The SOFA maximum was significantly lower in the PST group compared with the control group (7.8 ± 3.0 v 9.2 ± 3.4, P < 0.0001). Multivariate logistic regression analysis demonstrated the incidence of the severe multiorgan dysfunction, measured by SOFA maximum ≥11, was dramatically reduced in the PST group (OR, 0.68, 95% CI 0.50-0.92, P=0.013). Furthermore, preoperative statin therapy (PST) might be associated with a decreased risk of postoperative major adverse cardiovascular and cerebral events and acute kidney injury, but an increased risk of postoperative hepatic inadequacy.

Conclusion

SOFA maximum was significantly lower in the PST group compared with the control group and the incidence of the severe multiorgan dysfunction was dramatically reduced in the PST group. The findings of this study might shed new light on questions of positive or negative effects of PST on multiple organ function after high-risk CABG, so as to ultimately improve high-risk patient in-hospital outcomes from CABG.

Preoperative statins are associated with a reduced risk of postoperative delirium following vascular surgery

Delirium is a common complication of vascular surgery. The protective effect of preoperative statins on delirium after vascular surgery is controversial. The authors hypothesized that preoperative statin administration would decrease the incidence of delirium after vascular surgery. From May 2010 to May 2015, 1,132 patients underwent vascular surgery. Postoperative delirium was diagnosed from patients’ medical records. The incidence of delirium was 11.5%. The preoperative statin exposure was not associated with reduced delirium in the univariate analysis. After adjusting for covariates, preoperative statin exposure was associated with reduced delirium (OR, 0.54; 95% CI, 0.33–0.87; p = 0.011). This favor effect of statin for delirium was observed after propensity matching (OR, 0.59; 95% CI, 0.34–1.02; p = 0.060). However, the median hospital lengths of stay and in-hospital mortality were not statistically different between the two groups. CRP(C-reactive protein) levels in the unmatched population were lower in the preoperative statin group compared with the other group (p<0.001), however, there was only numerically different without statistical difference after matching (p = 0.083). Preoperative statin use was associated with a decreased incidence of postoperative delirium in patients who underwent vascular surgery. However, preoperative statin did not reduce mortality rate and hospital stay.

Lack of Association between Preoperative Statin Use and Respiratory and Neurologic Complications after Cardiac Surgery

Background

Statins may reduce the risk of pulmonary and neurologic complications after cardiac surgery.

Methods

The authors acquired data for adults who had coronary artery bypass graft, valve surgery, or combined procedures. The authors matched patients who took statins preoperatively to patients who did not. First, the authors assessed the association between preoperative statin use and the primary outcomes of prolonged ventilation (more than 24 h), pneumonia (positive cultures of sputum, transtracheal fluid, bronchial washings, and/or clinical findings consistent with the diagnosis of pneumonia), and in-hospital all-cause mortality, using logistic regressions. Second, the authors analyzed the collapsed composite of neurologic complications using logistic regression. Intensive care unit and hospital length of stay were evaluated with Cox proportional hazard models.

Results

Among 14,129 eligible patients, 6,642 patients were successfully matched. There was no significant association between preoperative statin use and prolonged ventilation (statin: 408/3,321 [12.3%] vs. nonstatin: 389/3,321 [11.7%]), pneumonia (44/3,321 [1.3%] vs. 54/3,321 [1.6%]), and in-hospital mortality (52/3,321 [1.6%] vs. 43/3,321 [1.3%]). The estimated odds ratio was 1.06 (98.3% CI, 0.88 to 1.27) for prolonged ventilation, 0.81 (0.50 to 1.32) for pneumonia, and 1.21 (0.74 to 1.99) for in-hospital mortality. Neurologic outcomes were not associated with preoperative statin use (53/3,321 [1.6%] vs. 56/3,321 [1.7%]), with an odds ratio of 0.95 (0.60 to 1.50). The length of intensive care unit and hospital stay was also not associated with preoperative statin use, with a hazard ratio of 1.04 (0.98 to 1.10) for length of hospital stay and 1.00 (0.94 to 1.06) for length of intensive care unit stay.

Conclusions

Preoperative statin use did not reduce pulmonary or neurologic complications after cardiac surgery.

Efficacy of Different Perioperative Statin Regimens on Protection Against Post-Coronary Artery Bypass Grafting Major Adverse Cardiac and Cerebral Events

OBJECTIVES

Comparing different perioperative statin regimens for the prevention of post-coronary artery bypass grafting adverse events.

DESIGN

A randomized, prospective study.

SETTING

Cardiothoracic surgical units in a government hospital.

PARTICIPANTS

The study comprised 94 patients scheduled for elective, isolated on- or off- pump coronary artery bypass grafting.

INTERVENTIONS

Patients were assigned randomly to 1 of the following 3 treatment groups: group I (80 mg of atorvastatin/day for 2 days preoperatively), group II (40 mg of atorvastatin/day for 5-9 days preoperatively), or group III (80 mg of atorvastatin/day for 5-9 days preoperatively). The same preoperative doses were restarted postoperatively and continued for 1 month.

MEASUREMENTS AND MAIN RESULTS

Cardiac troponin I, creatine kinase, and C-reactive protein (CRP) levels were assayed preoperatively; at 8, 24, and 48 hours postoperatively; and at discharge. CRP levels at 24 hours (p = 0.045) and 48 hours (p = 0.009) were significantly lower in group III compared with the other 2 groups. However, troponin I levels at 8 hours (p = 0.011) and 48 hours (p = 0.025) after surgery were significantly lower in group II compared with group III. The incidence of postoperative major adverse cardiac and cerebrovascular events was assessed, and there was no significant difference among the 3 groups.

CONCLUSION

The 3 regimens did not result in any significant difference in outcomes, but only simple trends. The higher-dose regimen resulted in a significant reduction in the CRP level. Thus, more studies are needed to confirm the benefit of higher-dose statins for the protection from post-coronary artery bypass grafting adverse events.

Perioperative Statin Therapy for Patients Undergoing Coronary Artery Bypass Grafting

Coronary artery bypass grafting is associated with an intense systemic inflammatory response, which is linked to postoperative complications. Beyond lipid lowering, statins exert a constellation of beneficial actions, including an antiinflammatory role, known as pleiotropic effects. There is increasing evidence that perioperative statin therapy improves outcomes in patients undergoing coronary artery bypass grafting. Statins are underused in the coronary artery bypass grafting population, because perioperative discontinuation remains a common practice. This article provides an extensive review of the available literature on the effect of perioperative statin therapy on post–coronary artery bypass grafting outcomes and weighs the evidence for the concerns about increased incidence of statin-related adverse effects in this setting.

Meta-analysis of patients taking statins before revascularization and aortic valve surgery

Statin intake before cardiac surgery is associated with favorable outcomes. We sought to analyze the evidence for statin pretreatment before isolated coronary artery bypass graft surgery and aortic valve replacement surgery. In this meta-analysis, we demonstrate beneficial results for the endpoints mortality, stroke, atrial fibrillation, and length of stay in hospital in 36,053 statin-pretreated coronary artery bypass graft surgery patients compared with control subjects retrieved from 32 studies, but fail to detect relevant advantages through preoperative statin therapy for 3,091 patients undergoing aortic valve replacement from four trials. Strict adherence to guidelines recommending statin treatment before CABG surgery is therefore mandatory.

Can statins improve outcomes after isolated cardiac valve surgery? A systematic literature review

BACKGROUND

HMG CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase inhibitors, or statins, have been associated with an improvement in outcomes after coronary artery surgery for some time; however, their role in isolated valve surgery (IVS) remains undetermined.

HYPOTHESIS

The pleiotropic effects of statins may produce similar beneficial effects on outcomes after IVS.

METHODS

A systematic review of the literature was performed investigating the role of statins in bioprosthetic valve replacement.

RESULTS

Nine observational studies (7 retrospective, 2 prospective) incorporating a total of 18 154 patients were found investigating the role of statin therapy in bioprosthetic valve replacement.

CONCLUSIONS

There is presently insufficient evidence to recommend routine statin therapy in IVS, unless concomitant hypercholesterolemia or coronary artery disease is present. A prospective study clearly defining the dose, type, and duration of therapy is now required to finally clarify whether statins alone confer a postoperative benefit in these patients.

Preoperative statin therapy in cardiac surgery: a meta-analysis of 90,000 patients

The objective of this systematic literature review with meta-analysis was to determine the strength of evidence for a preoperative statin on the reduction of adverse postoperative outcomes in patients undergoing cardiac surgery. Randomized controlled (RCT) and observational trials were searched in online databases that reported about the effects of preoperative statin therapy on major adverse clinical outcomes after cardiac surgery. Analysed outcomes included early all-cause mortality, myocardial infarction, atrial fibrillation (AF), stroke and renal failure using a priori-defined criteria. Effect estimates were calculated and are given as odds ratio (OR) with 95% confidence intervals (95% CI) using fixed- or random-effect models. Literature search of all major databases retrieved 2371 studies. After screening, a total of 54 trials were identified (12 RCT, 42 observational) that reported outcomes of 91 491 cardiac surgery patients with (n = 46 614; 51%) or without (n = 44 877; 49%) preoperative statin therapy. Preoperative statin use resulted in a 0.9% absolute risk (2.6 vs 3.5%) and a 31% odds reduction for early all-cause mortality (OR 0.69; 95% CI 0.59-0.81; P < 0.0001). In addition, statin treatment before surgery was associated with a substantial reduction (P < 0.01) in the postoperative end-points AF (OR 0.71; 95% CI 0.61-0.82), new-onset AF (OR 0.68; 95% CI 0.54-0.85), stroke (OR 0.83; 95% CI 0.74-0.93), stay on intensive care unit (weighted mean difference [WMD] -0.14; 95% CI -0.23 to -0.03; P < 0.01) and in-hospital stay (WMD -0.57; 95% CI -0.76 to -0.38; P < 0.01). No statistical differences were found between groups with regard to myocardial infarction or renal failure. In conclusion, the current systematic review strengthens the evidence that preoperative statin therapy extends substantial clinical benefit to early postoperative outcomes in cardiac surgery patients.

Preoperative statin therapy is not associated with a decrease in the incidence of delirium after cardiac operations

BACKGROUND

Delirium after cardiac operations is associated with significant morbidity and death. Statins have been recently suggested to exert protective cerebral effects. This study investigated whether preoperative statins were associated with decreased incidence of postoperative delirium in patients undergoing coronary artery bypass grafting.

METHODS

The study enrolled 4,659 consecutive patients (21% women; age, 67.8±9.2 years) undergoing coronary artery bypass grafting. A propensity score-based optimal-matching algorithm was used to match 1,577 patients receiving preoperative statins with a control group (1:1). Patients were screened for delirium in the intensive care unit according to the Confusion Assessment Method for the intensive care unit.

RESULTS

Delirium affected 89 patients (3%), and preoperative statin administration was not multivariably associated with a decreased incidence of delirium (odds ratio, 1.52; 95% confidence interval, 0.97 to 2.37; p=0.18) and was also unrelated to a delirium decrease in patient subgroups undergoing isolated coronary artery bypass grafting (odds ratio, 1.31; 95% confidence interval, 0.68 to 2.52; p=0.51) or combined valvular procedures (odds ratio, 1.72; 95% confidence interval, 0.96 to 3.07, p=0.08). Similar results were observed for age groups and cardiopulmonary bypass durations. Patients affected by postoperative delirium experienced a longer hospital stay (25th to 75th percentile) of 11 (7 to 18 days) vs 7 days (7 to 8 days, p<0.001) and 12% hospital mortality vs 1% (p<0.001).

CONCLUSIONS

Preoperative statins were not associated with a decreased incidence of delirium in patients undergoing coronary revascularization.

Lipid-lowering therapy and coronary artery bypass graft surgery: what are the benefits?

PURPOSE OF REVIEW

Despite their apparent benefits, statins remain underutilized after coronary artery bypass graft (CABG) surgery. To summarize the literature regarding statin therapy and CABG, we performed a systematic review of the Medline database from 1987-2011 to assess the benefits of statins in CABG patients, including the role of high-dose therapy, and highlight areas for future study.

RECENT FINDINGS

When administered prior to CABG, statins reduce the risk of perioperative mortality, stroke, and atrial fibrillation. After CABG, statins limit the progression of atherosclerosis in native coronary arteries, inhibit the process of saphenous vein graft disease, and improve vein graft patency. Furthermore, postoperative statins reduce the recurrence of cardiovascular events and improve all-cause mortality. High-intensity statin therapy early after surgery may benefit CABG patients, but this is yet to be evaluated prospectively.

SUMMARY

Statins clearly improve the outcomes of CABG patients. In the absence of contraindications, all patients undergoing CABG are candidates for life-long statin therapy, with initiation recommended as soon as coronary disease is documented. Statins should be restarted early after surgery. However, the optimal postoperative lipid-lowering regimen remains unknown and should be the subject of upcoming trials. Strategies directed toward improving statin prescription rates and patient adherence should also be priorities for future research.

Integrating outcome benefit into anesthetic design: the promise of steroids and statins

Steroids and statins may facilitate the integration of anesthetic design with clinical outcome. Although steroids clearly benefit adult cardiac surgical patents, the evidence is weaker in pediatric cardiac surgery. Current large randomized trials of steroids likely will determine the future role of steroids in adult cardiac surgery. In the intensive care unit, steroid therapy is indicated in septic shock that is refractory to fluid and pressor therapy. Recent data, however, indicate that liberal steroid therapy for sepsis may have adverse outcome consequences. A 2nd concern in the intensive care unit is acute adrenal suppression secondary to bolus etomidate therapy because it may be deleterious in patients with septic shock. Possible clinical solutions include alternative induction agents, concomitant steroid therapy, and recent etomidate derivatives. Statins also reduce mortality and atrial fibrillation after cardiac surgery. Furthermore, they slow the progression of rheumatic valvular stenosis, an important consideration in the developing world. Statins also may reduce delirium, stroke, and acute renal injury after cardiac surgery, but further randomized trials are required before definitive recommendations can be formulated. Statins are essential in vascular surgery because they reduce mortality, myocardial ischemia, and acute renal injury. As a result, they have been recommended highly for outcome enhancement in recent perioperative guidelines. Although they may improve survival in sepsis, further investigation is indicated to define their therapeutic role.

Progress in perioperative medicine: focus on statins

Beyond cholesterol reduction, statins have multiple beneficial influences on vascular endothelial function, atherosclerotic plaque stability, inflammation, and thrombosis. These favorable pleiotropic effects may be the basis for their perioperative risk reduction in cardiothoracic and vascular procedures. The published evidence suggests that statins offer significant outcome benefits throughout perioperative practice. Because statin therapy significantly reduces the perioperative risk for patients undergoing cardiovascular procedures, they already are recommended in published guidelines. Beyond cardiac risk reduction, statin therapy also may protect the brain and the kidney in the perioperative setting, both in cardiac and vascular surgery. The pleiotropic effects of statins also appear to have therapeutic roles in the progression of valve disease, sepsis, and venous thrombosis. Further trials are required to provide data to drive their safe and comprehensive perioperative application for optimal patient outcome both in the short term and the long term. Because there are multiple randomized trials currently in progress throughout perioperative medicine, it is very likely that the indications for statins will be expanded significantly.