Combination Lipid-Lowering Therapies for the Prevention of Recurrent Cardiovascular Events

Benefits of intensive lipid-lowering therapies in patients with acute coronary syndrome: a systematic review and meta-analysis

BACKGROUND

Previous meta-analyses have investigated the efficacy of lipid-lowering therapies for atherosclerotic cardiovascular disease; however, few have focused on patients with acute coronary syndrome (ACS). This meta-analysis aimed to compare the benefits of intensive lipid-lowering therapy with those of background statin therapy in patients with ACS.

METHODS

Searches were performed on PubMed, Embase, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases for articles published until April 13, 2023. Randomized controlled trials that compared intensive lipid-lowering therapies and background statin therapies in patients with prior ACS and recorded the outcome of three-point major cardiovascular events (MACE) were included. The risk ratio (RR) with 95% confidence interval (CI) was used as a measure of primary and secondary outcomes.

RESULTS

Nine trials involving 38,640 patients with ACS were identified. Pooled results suggested that intensive lipid-lowering therapies are associated with a reduction in the risk of three-point MACE (RR, 0.88; 95% CI, 0.83-0.94; p < 0.001), recurrent ACS (RR, 0.82; 95% CI, 0.71-0.96; p = 0.013), nonfatal myocardial infarction (MI) (RR, 0.87; 95% CI, 0.81-0.93; p < 0.001), stroke (RR, 0.83; 95% CI, 0.73-0.94; p = 0.003), and unstable angina-related hospitalization (RR, 0.57; 95% CI, 0.33-0.99; p = 0.046), but not all-cause mortality (RR, 0.94; 95% CI, 0.82-1.07; p = 0.329), cardiovascular disease-related mortality (RR, 0.96; 95% CI, 0.88-1.06; p = 0.457) or coronary revascularization (RR, 0.89; 95% CI, 0.79-1.00; p = 0.057).

CONCLUSIONS

Intensive lipid-lowering therapies may reduce the risk of three-point MACE, recurrent ACS, nonfatal MI, stroke, and hospitalization for unstable angina in patients with ACS undergoing background statin therapy. These results may assist in clinical decision-making for the secondary prevention of cardiovascular events to initiate intensive lipid-lowering therapies immediately after ACS.

A Modern Approach to Dyslipidemia

Lipid disorders involving derangements in serum cholesterol, triglycerides, or both are commonly encountered in clinical practice and often have implications for cardiovascular risk and overall health. Recent advances in knowledge, recommendations, and treatment options have necessitated an updated approach to these disorders. Older classification schemes have outlived their usefulness, yielding to an approach based on the primary lipid disturbance identified on a routine lipid panel as a practical starting point. Although monogenic dyslipidemias exist and are important to identify, most individuals with lipid disorders have polygenic predisposition, often in the context of secondary factors such as obesity and type 2 diabetes. With regard to cardiovascular disease, elevated low-density lipoprotein cholesterol is essentially causal, and clinical practice guidelines worldwide have recommended treatment thresholds and targets for this variable. Furthermore, recent studies have established elevated triglycerides as a cardiovascular risk factor, whereas depressed high-density lipoprotein cholesterol now appears less contributory than was previously believed. An updated approach to diagnosis and risk assessment may include measurement of secondary lipid variables such as apolipoprotein B and lipoprotein(a), together with selective use of genetic testing to diagnose rare monogenic dyslipidemias such as familial hypercholesterolemia or familial chylomicronemia syndrome. The ongoing development of new agents-especially antisense RNA and monoclonal antibodies-targeting dyslipidemias will provide additional management options, which in turn motivates discussion on how best to incorporate them into current treatment algorithms.

Evidence for changing lipid management strategy to focus on non-high density lipoprotein cholesterol

Low-density lipoprotein cholesterol (LDL-C) has been recommended as the primary treatment target on lipid management in coronary heart disease (CHD) patients for past several decades. However, even by aggressive LDL-C lowering treatment, patients still present a significant residual risk of major adverse cardiovascular events (MACE). Non-high-density lipoprotein cholesterol (non-HDL-C) contained all the atherogenic lipoproteins, such as chylomicron, very-low density lipoprotein (VLDL), LDL, intermediate density lipoprotein (IDL). Many prospective observation studies have found that non-HDL-C was better than LDL-C in predicting risks of MACE. Since non-HDL-C appears to be superior for risk prediction beyond LDL-C, current guidelines have emphasize the importance of non-HDL-C for guiding cardiovascular prevention strategies and have flagged non-HDL-C as a co-primary therapeutic target. The goals of non-HDL-C were recommended as 30 mg/dl higher than the corresponding LDL-C goals, but the value seemed inappropriate. This review provide evidence for changing lipid management strategy to focus on non-HDL-C and appropriate values for adding to LDL-C goals would be proposed.