Benefits of statin therapy in patients with special risks: coronary bypass surgery, stable coronary disease, and acute coronary syndromes

Non-antiarrhythmic agents for prevention of postoperative atrial fibrillation: role of statins

PURPOSE OF REVIEW

Atrial fibrillation is the most common arrhythmia following cardiac surgery, having both serious medical and socioeconomic consequences. Although there are established antiarrhythmic agents for preventing and treating postoperative atrial fibrillation, these therapies are neither 100% reliable, nor without risks and limitations. Thus, there remains a strong need for non-antiarrhythmic, adjunctive therapies for the prevention of postoperative atrial fibrillation.

RECENT FINDINGS

Long-term statin administration in ambulatory patients is associated with a reduced risk of adverse cardiovascular events, including death, myocardial infarction, stroke, renal dysfunction and atrial fibrillation. Recent evidence suggests, however, that statins may also reduce the risk of acute adverse outcomes following invasive procedures, including postoperative atrial fibrillation. Although the exact mechanisms by which statins may reduce postoperative atrial fibrillation are unclear, accumulating evidence suggests that statins exert multiple effects independent of their effect on LDL cholesterol. For example, in patients with acute coronary syndromes, statin therapy has been shown to modulate remodeling of the cardiac extracellular matrix and to reduce markers of inflammation, including C-reactive protein, serum amyloid A, tumor necrosis factor-alpha, and IL-6.

SUMMARY

Perioperative statin therapy may represent an important non-antiarrhythmic, adjunctive therapeutic strategy for the prevention of postoperative atrial fibrillation.

Time as a Variable With Niacin Extended‐Release/Lovastatin vs. Atorvastatin and Simvastatin

Time may be an important variable when evaluating the efficacy of lipid-altering drugs. In this analysis of the Advicor Versus Other Cholesterol-Modulating Agents Trial Evaluation, niacin extended-release/lovastatin 1000/40 mg was as effective as atorvastatin 10 mg and more effective than simvastatin (both 10 mg and 20 mg) in achieving low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol treatment goals. The titration schedule for this study included the initiation of niacin-extended release/lovastatin 500/20 mg once a day for 4 weeks, titrated to the starting dose of 1000/40 mg after 4 weeks, and then titrated to the final dose of 2000/40 mg. The titration schedule for both atorvastatin and simvastatin was 10 mg per day for 8 weeks and then titrated to 40 mg per day. Using this schedule, 50% of niacin extended-release/lovastatin and atorvastatin patients reached low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol treatment goals within approximately 7 weeks, compared with simvastatin, in which 50% reached both treatment goals in 13-14 weeks. These time differences may have potential clinical relevance in reducing coronary heart disease risk.

Preoperative statin therapy is associated with reduced cardiac mortality after coronary artery bypass graft surgery

OBJECTIVE

Statin therapy in ambulatory populations is associated with a significant reduction in adverse cardiovascular events, including death and myocardial infarction. Much less is known about the beneficial effects of statins on acute perioperative cardiovascular events. The purpose of this study was to determine whether preoperative statin therapy is associated with a reduced risk of early cardiac death or nonfatal, in-hospital postoperative myocardial infarction after primary, elective coronary artery bypass graft surgery requiring cardiopulmonary bypass.

METHODS

The Multicenter Study of Perioperative Ischemia (McSPI) Epidemiology II Study was a prospective, longitudinal study of 5436 patients undergoing coronary artery bypass graft surgery between November 1996 and June 2000 at 70 centers in 17 countries. The present study consisted of a pre-specified subset of these subjects divided into patients receiving (n = 1352) and not receiving (n = 1314) preoperative statin therapy. To control for potential bias related to use of statin therapy, the study estimated propensity scores by logistic regression to determine the predicted probability of inclusion in the "statin" group. Multivariate, stepwise logistic regression was then performed, controlling for patient demographics, medical history, operative characteristics, and propensity score to determine whether preoperative statin therapy was independently associated with a reduction in the risk of early (DOS-POD3) cardiac death and/or nonfatal, in-hospital postoperative myocardial infarction.

RESULTS

Preoperative statin therapy was independently associated with a significant reduction (adjusted odds ratio [OR] 0.25; 95% confidence intervals [CI] 0.07-0.87) in the risk of early cardiac death after primary, elective coronary bypass surgery (0.3% vs 1.4%; P < .03), but was not associated with a reduced risk of postoperative nonfatal, in-hospital myocardial infarction (7.9% vs 6.2%; P = not significant). Discontinuation of statin therapy after surgery was independently associated with a significant increase in late (POD4-discharge) all-cause mortality (adjusted OR 2.64; 95% CI 1.32-5.26) compared with continuation of statin therapy (2.64% vs 0.60%; P < .01). This was true even when controlling for the postoperative discontinuation of aspirin, beta-blocker, or angiotensin-converting enzyme inhibitor therapy. Discontinuation of statin therapy after surgery was also independently associated with a significant increase in late cardiac mortality (adjusted OR 2.95; 95% CI 1.31-6.66) compared with continuation of statin therapy (1.91% vs 0.45%; P < 0.01).

CONCLUSIONS

Preoperative statin use is associated with reduced cardiac mortality after primary, elective coronary artery bypass grafting. Postoperative statin discontinuation is associated with increased in-hospital mortality. Although further randomized trials are needed to confirm these findings, these data suggest the importance of perioperative statin administration.

The evaluation and management of dyslipidemia and impaired glucose metabolism during acute coronary syndromes

Dyslipidemia and hyperglycemia are common among patients presenting with acute coronary syndromes (ACS), and patients with ACS and metabolic disorders are at increased risk for worse outcomes. Although guidelines for the diagnosis and management of dyslipidemia, diabetes, and the metabolic syndrome have been published, these guidelines have not specifically focused on the ACS patient population. Recent observational registries and clinical trials have advanced the appreciation of these disorders in ACS populations and data from these studies support aggressive efforts to diagnose and treat dyslipidemia and hyperglycemia in patients admitted for ACS.

Statins are associated with a reduced incidence of perioperative mortality after coronary artery bypass graft surgery

BACKGROUND

Statin therapy in nonsurgical patient populations is associated with a significant reduction in adverse cardiovascular events, including death, myocardial infarction (MI), and stroke. Recently, statin therapy was shown to be associated with a reduced incidence of postoperative mortality in patients undergoing major noncardiac vascular surgery. We investigated the influence of preoperative statin therapy on adverse outcomes after primary coronary artery bypass graft (CABG) surgery.

METHODS AND RESULTS

A retrospective cohort study of patients undergoing primary CABG surgery with cardiopulmonary bypass (CPB) (n=1663) between January 1, 2000 and December 31, 2001 at the Texas Heart Institute was performed. Patients were classified into 2 groups: patients receiving preoperative statin therapy (n=943) and patients not receiving preoperative antihyperlipidemic therapy (n=720). To determine if preoperative statin therapy was independently associated with a reduction in the risk of adverse postoperative outcomes, multivariate stepwise logistic regression was performed controlling for patient demographics, medical history, and preoperative medications. Multivariate logistic regression analysis demonstrated that preoperative statin therapy was independently associated with a significant reduction ( approximately 50%) in the risk of 30-day all-cause mortality (3.75% versus 1.80%; P<0.05). The adjusted odds ratio for early mortality in patients receiving preoperative statin therapy compared with patients not receiving antihyperlipidemic agents was 0.53 (95% CI, 0.28 to 0.99). Statin therapy was not independently associated with a reduced risk of postoperative MI, cardiac arrhythmias, stroke, or renal dysfunction. In an attempt to further control for selection bias related to the choice of therapy, multivariate analysis of a propensity-matched cohort of 1362 patients revealed that preoperative statin therapy was independently associated with a significant reduction in the composite endpoint of 30-day all-cause mortality and stroke (7.1% versus 4.6%; P<0.05).

CONCLUSIONS

Preoperative statin therapy may reduce the risk of early mortality after primary CABG surgery with CPB.

Statins are less effective in common daily practice among patients with hypercholesterolemia: the REALITY-PHARMO study

BACKGROUND

To study the use and effectiveness of lipid-lowering drugs with respect to lowering of cholesterol levels in routine daily practice.

METHODS

20 392 patients for whom lipid levels records were available between January 1991 and December 2001 were included in this retrospective population based cohort study. From this group of patients 1899 patients started treatment during the study period and had at least one baseline cholesterol measurement during the six months prior to the initiation of lipid lowering drugs and at least one cholesterol measurement after initiation. A patient was defined to be 'at goal' if the patient had a total cholesterol less than 5.0 mmol/L.

RESULTS

Our results indicate that only 30.2% of all treated patients achieved goal in the first year of treatment. After the introduction of new guidelines in 1998, recommending more aggressive treatment, the goal attainment percentage rose from 22.4% of those patients treated before 1998 to 42.3% for those in whom treatment was initiated after 1998.

CONCLUSION

The percentage of patients achieving guideline recommended goal is low in real-life even in patients treated with high dose statins.