The effect of statin therapy on plaque regression following acute coronary syndrome: a meta-analysis of prospective trials

Treatment Effects in Randomized and Nonrandomized Studies of Pharmacological Interventions: A Meta-Analysis

Importance

Randomized clinical trials (RCTs) are widely regarded as the methodological benchmark for assessing clinical efficacy and safety of health interventions. There is growing interest in using nonrandomized studies to assess efficacy and safety of new drugs.

Objective

To determine how treatment effects for the same drug compare when evaluated in nonrandomized vs randomized studies.

Data Sources

Meta-analyses published between 2009 and 2018 were identified in MEDLINE via PubMed and the Cochrane Database of Systematic Reviews. Data analysis was conducted from October 2019 to July 2024.

Study Selection

Meta-analyses of pharmacological interventions were eligible for inclusion if both randomized and nonrandomized studies contributed to a single meta-analytic estimate.

Data Extraction and Synthesis

For this meta-analysis using a meta-epidemiological framework, separate summary effect size estimates were calculated for nonrandomized and randomized studies within each meta-analysis using a random-effects model and then these estimates were compared. The reporting of this study followed the Guidelines for Reporting Meta-Epidemiological Methodology Research and relevant portions of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline.

Main Outcome and Measures

The primary outcome was discrepancies in treatment effects obtained from nonrandomized and randomized studies, as measured by the proportion of meta-analyses where the 2 study types disagreed about the direction or magnitude of effect, disagreed beyond chance about the effect size estimate, and the summary ratio of odds ratios (ROR) obtained from nonrandomized vs randomized studies combined across all meta-analyses.

Results

A total of 346 meta-analyses with 2746 studies were included. Statistical conclusions about drug benefits and harms were different for 130 of 346 meta-analyses (37.6%) when focusing solely on either nonrandomized or randomized studies. Disagreements were beyond chance for 54 meta-analyses (15.6%). Across all meta-analyses, there was no strong evidence of consistent differences in treatment effects obtained from nonrandomized vs randomized studies (summary ROR, 0.95; 95% credible interval [CrI], 0.89-1.02). Compared with experimental nonrandomized studies, randomized studies produced on average a 19% smaller treatment effect (ROR, 0.81; 95% CrI, 0.68-0.97). There was increased heterogeneity in effect size estimates obtained from nonrandomized compared with randomized studies.

Conclusions and Relevance

In this meta-analysis of treatment effects of pharmacological interventions obtained from randomized and nonrandomized studies, there was no overall difference in effect size estimates between study types on average, but nonrandomized studies both overestimated and underestimated treatment effects observed in randomized studies and introduced additional uncertainty. These findings suggest that relying on nonrandomized studies as substitutes for RCTs may introduce additional uncertainty about the therapeutic effects of new drugs.

ANGPTL4 stabilizes atherosclerotic plaques and modulates the phenotypic transition of vascular smooth muscle cells through KLF4 downregulation

Atherosclerosis, the leading cause of death, is a vascular disease of chronic inflammation. We recently showed that angiopoietin-like 4 (ANGPTL4) promotes cardiac repair by suppressing pathological inflammation. Given the fundamental contribution of inflammation to atherosclerosis, we assessed the role of ANGPTL4 in the development of atherosclerosis and determined whether ANGPTL4 regulates atherosclerotic plaque stability. We injected ANGPTL4 protein twice a week into atherosclerotic Apoe-/- mice and analyzed the atherosclerotic lesion size, inflammation, and plaque stability. In atherosclerotic mice, ANGPTL4 reduced atherosclerotic plaque size and vascular inflammation. In the atherosclerotic lesions and fibrous caps, the number of α-SMA(+), SM22α(+), and SM-MHC(+) cells was higher, while the number of CD68(+) and Mac2(+) cells was lower in the ANGPTL4 group. Most importantly, the fibrous cap was significantly thicker in the ANGPTL4 group than in the control group. Smooth muscle cells (SMCs) isolated from atherosclerotic aortas showed significantly increased expression of CD68 and Krüppel-like factor 4 (KLF4), a modulator of the vascular SMC phenotype, along with downregulation of α-SMA, and these changes were attenuated by ANGPTL4 treatment. Furthermore, ANGPTL4 reduced TNFα-induced NADPH oxidase 1 (NOX1), a major source of reactive oxygen species, resulting in the attenuation of KLF4-mediated SMC phenotypic changes. We showed that acute myocardial infarction (AMI) patients with higher levels of ANGPTL4 had fewer vascular events than AMI patients with lower levels of ANGPTL4 (p < 0.05). Our results reveal that ANGPTL4 treatment inhibits atherogenesis and suggest that targeting vascular stability and inflammation may serve as a novel therapeutic strategy to prevent and treat atherosclerosis. Even more importantly, ANGPTL4 treatment inhibited the phenotypic changes of SMCs into macrophage-like cells by downregulating NOX1 activation of KLF4, leading to the formation of more stable plaques.

Influence of statin therapy on antiphospholipid antibodies and endothelial dysfunction in young patients with coronary artery disease and systemic lupus erythematosus

INTRODUCTION

Antiphospholipid antibodies (aPL) affect atherogenesis and may cause thromboembolism in systemic lupus erythematosus (SLE) and coronary artery disease (CAD). Intensive treatment with statins may reduce inflammation and decrease the number of thrombotic events. That may explain the beneficial effect of statin therapy in SLE and CAD. This study was established to investigate the influence of statin treatment on aPL antibody levels and selected endothelial dysfunction markers in CAD and SLE patients.

MATERIAL AND METHODS

Fifty-eight patients - 40 after coronary revascularization (age 38.9 (27-46), 35 males) and 18 with clinically stable SLE (age 38.8 (18-62), 1 male) - were enrolled in the study. In both groups intensive atorvastatin treatment was administered. At baseline and after 1 year of follow-up serology tests were performed: anticardiolipin antibodies (aCL), anti-β2 glycoprotein I (aβ2GPI), lupus anticoagulant (LA), C-reactive protein (CRP), soluble form of intracellular adhesion molecule-1 (sICAM-1), vWF:Ag.

RESULTS

Coronary artery disease patients in 1 year follow-up revealed a decrease of aβ2GPI IgG and CRP. There was a significant increase in aCL IgG, sICAM-1 and vWF:Ag. In SLE patients aPL levels showed no significant reduction after treatment.

CONCLUSIONS

In clinically stable patients IgM and IgG class aβ2GPI levels are higher in CAD than in SLE, whereas IgG class aCL levels are lower. Statin treatment decreases the CRP level in both SLE and CAD patients, while decreasing the aβ2GPI IgG level only in CAD patients.

The impact of lipid-lowering medications on coronary artery plaque characteristics

Atherosclerosis is the predominant cause of coronary artery disease. The last several decades have witnessed significant advances in lipid-lowering therapies, which comprise a central component of atherosclerotic cardiovascular disease prevention. In addition to cardiovascular risk reduction with dyslipidemia management, some lipid-based therapies show promise at the level of the atherosclerotic plaque itself through mechanisms governing lipid accumulation, plaque stability, local inflammation, endothelial dysfunction, and thrombogenicity. The capacity of lipid-lowering therapies to modify atherosclerotic plaque burden, size, composition, and vulnerability should correlate with their ability to reduce disease progression. This review discusses plaque characteristics, diagnostic modalities to evaluate these characteristics, and how they are altered by current and emerging lipid-lowering therapies, all in human coronary artery disease.

Comparison of High-Statin Therapy vs Moderate-Statin Therapy in Achieving Positive Low-Density Lipoprotein Change in Patients After Acute Coronary Syndrome: A Randomized-Control Trial

INTRODUCTION

Statin use in secondary prevention after acute coronary syndrome (ACS) can play an important role in enhancing clinical outcomes, this has been proven in several randomized trials. This study was conducted to compare the efficacy of moderate-intensity and high-intensity statins in controlling low-density lipoprotein (LDL) after ACS.

METHODOLOGY

A randomized control trial was conducted at the Cardiology Department of Liaquat National Hospital, Karachi, Pakistan, from July 2020 to September 2021. During admission, patients were either started on a high-intensity statin dose (rosuvastatin 20 mg) or moderate-intensity statin (rosuvastatin 10 mg) by a computer-generated allocation sequence. Patients were followed-up in the outpatient department (OPD) after 3 months, and a lipid profile at follow-up was obtained. The percentage of LDL change was determined on 3 months of follow-up.

RESULTS

A total of 590 patients were enrolled in the study. Out of all participants enrolled, 334 (80.48%) completed the 3-month follow-up. The mean age of participants was 58.08 (+12.06) years. High-intensity statin therapy is positively associated with positive LDL change (adjusted odds ratio [AOR]=4.45, P-value=0.001).

CONCLUSION

Our data implies that high-intensity statin medication may be an initial therapeutic option to decrease LDL. However, future randomized clinical trials should corroborate these findings.

Thrombus aspiration without stenting in a patient with anterior STEMI: Regression and healing of an unstable plaque assessed by OCT at 24 months of follow-up

In selected cases, when STEMI caused by mild or moderate degree lesion with a large concomitant thrombus, additional OCT-guided PCI strategy after thrombus removal allows us to defer stenting with the follow-up natural healing of the vessel wall.

The effects of lipid-lowering therapy on coronary plaque regression: a systematic review and meta-analysis

To assess the influence of lipid-lowering therapy on coronary plaque volume, and to identify the LDL and HDL targets for plaque regression to provide a comprehensive overview. The databases searched (from inception to 15 July 2020) to identify prospective studies investigating the impact of lipid-lowering therapy on coronary plaque volume and including quantitative measurement of plaque volume by intravascular ultrasound after treatment. Thirty-one studies that included 4997 patients were selected in the final analysis. Patients had significantly lower TAV (SMD: 0.123 mm³; 95% CI 0.059, 0.187; P = 0.000) and PAV (SMD: 0.123%; 95% CI 0.035, 0.212; P = 0.006) at follow-up. According to the subgroup analyses, TAV was significantly reduced in the LDL < 80 mg/dL and HDL > 45 mg/dL group (SMD: 0.163 mm³; 95% CI 0.092, 0.234; P = 0.000), and PAV was significantly reduced in the LDL < 90 mg/dL and HDL > 45 mg/dL group (SMD: 0.186%; 95% CI 0.081, 0.291; P = 0.001).Thirty-one studies that included 4997 patients were selected in the final analysis. Patients had significantly lower TAV (SMD: 0.123 mm³; 95% CI 0.059, 0.187; P = 0.000) and PAV (SMD: 0.123%; 95% CI 0.035, 0.212; P = 0.006) at follow-up. According to the subgroup analyses, TAV was significantly reduced in the LDL < 80 mg/dL and HDL > 45 mg/dL group (SMD: 0.163 mm³; 95% CI 0.092, 0.234; P = 0.000), and PAV was significantly reduced in the LDL < 90 mg/dL and HDL > 45 mg/dL group (SMD: 0.186%; 95% CI 0.081, 0.291; P = 0.001). Our meta-analysis suggests that not only should LDL be reduced to a target level of < 80 mg/dL, but HDL should be increased to a target level of > 45 mg/dL to regress coronary plaques.

Trial Registration PROSPERO identifier: CRD42019146170.

High-intensity statin therapy yields better outcomes in acute coronary syndrome patients: a meta-analysis involving 26,497 patients

Background

Whether high-intensity statin treatment provides more clinical benefits compared with standard statin regimens in acute coronary syndrome (ACS) patients remains controversial. This meta-analysis aimed to comparatively assess high-intensity and standard statin regimens for efficacy and safety in patients with ACS.

Methods

The PubMed, EMBASE, and Cochrane Library databases were searched for studies assessing high-intensity vs. standard statin regimens for ACS treatment from inception to April 2020. The publication language was limited to English, and 16 randomized controlled trials were finally included in this study, with a total of 26,497 patients.

Results

Compared to the standard statin regimens, the relative ratio (RR) of major adverse cardiovascular events (MACE) in ACS patients treated by high-intensity statin was 0.77 (95%CI, 0.68–0.86; P < 0.00001; prediction interval, 0.56–1.07). In subgroup analysis, high-intensity statin therapy resulted in more clinical benefits regarding MACE compared with standard statin treatment in both Asian (RR = 0.77; 95%CI, 0.61–0.98; P = 0.03) and non-Asian (RR = 0.79; 95%CI, 0.71–0.89; P < 0.0001) patients. Although adverse events were acceptable in patients with ACS administered high-intensity statin therapy, this treatment was associated with a higher rate of adverse events (4.99% vs. 2.98%), including myopathy/myalgia and elevated liver enzymes, as reflected by elevated serum aminotransferase or aminotransferase amounts.

Conclusion

The current findings indicated that high-intensity statin therapy might be beneficial in patients with ACS, and close monitoring for adverse effects should be performed.

Inflammation and its resolution in atherosclerosis: mediators and therapeutic opportunities

Atherosclerosis is a lipid-driven inflammatory disease of the arterial intima in which the balance of pro-inflammatory and inflammation-resolving mechanisms dictates the final clinical outcome. Intimal infiltration and modification of plasma-derived lipoproteins and their uptake mainly by macrophages, with ensuing formation of lipid-filled foam cells, initiate atherosclerotic lesion formation, and deficient efferocytotic removal of apoptotic cells and foam cells sustains lesion progression. Defective efferocytosis, as a sign of inadequate inflammation resolution, leads to accumulation of secondarily necrotic macrophages and foam cells and the formation of an advanced lesion with a necrotic lipid core, indicative of plaque vulnerability. Resolution of inflammation is mediated by specialized pro-resolving lipid mediators derived from omega-3 fatty acids or arachidonic acid and by relevant proteins and signalling gaseous molecules. One of the major effects of inflammation resolution mediators is phenotypic conversion of pro-inflammatory macrophages into macrophages that suppress inflammation and promote healing. In advanced atherosclerotic lesions, the ratio between specialized pro-resolving mediators and pro-inflammatory lipids (in particular leukotrienes) is strikingly low, providing a molecular explanation for the defective inflammation resolution features of these lesions. In this Review, we discuss the mechanisms of the formation of clinically dangerous atherosclerotic lesions and the potential of pro-resolving mediator therapy to inhibit this process.

[Predictors of acute coronary syndrome in patients with ischaemic heart disease]

Acute coronary syndrome has for a long time been giving no way of decreasing mortality related to ischaemic heart disease. The primary cause of acute coronary syndrome in the majority of cases is rupture of an unstable atherosclerotic plaque in the coronary artery followed by thrombosis thereof. The main missions of modern cardiology include: assessment of the risk of acute coronary syndrome, identification of predictors of adverse events, and working-out of measures aimed at prevention and optimal management of patients with ischaemic heart disease. This article deals with clinical and morphological factors associated with destabilization of coronary plaques, their rupture, and the development of an acute coronary event.

Vulnerable Plaque, Characteristics, Detection, and Potential Therapies

Plaque development and rupture are hallmarks of atherosclerotic vascular disease. Despite current therapeutic developments, there is an unmet necessity in the prevention of atherosclerotic vascular disease. It remains a challenge to determine at an early stage if atherosclerotic plaque will become unstable and vulnerable. The arrival of molecular imaging is receiving more attention, considering it allows for a better understanding of the biology of human plaque and vulnerabilities. Various plaque therapies with common goals have been tested in high-risk patients with cardiovascular disease. In this work, the process of plaque instability, along with current technologies for sensing and predicting high-risk plaques, is debated. Updates on potential novel therapeutic approaches are also summarized.

What We Have Learned from the Recent Meta-analyses on Diagnostic Methods for Atherosclerotic Plaque Regression

PURPOSE OF REVIEW

Atherosclerosis has major morbidity and mortality implications globally. While it has often been considered an irreversible degenerative process, recent evidence provides compelling proof that atherosclerosis can be reversed. Plaque regression is however difficult to appraise and quantify, with competing diagnostic methods available. Given the potential of evidence synthesis to provide clinical guidance, we aimed to review recent meta-analyses on diagnostic methods for atherosclerotic plaque regression.

RECENT FINDINGS

We identified 8 meta-analyses published between 2015 and 2017, including 79 studies and 14,442 patients, followed for a median of 12 months. They reported on atherosclerotic plaque regression appraised with carotid duplex ultrasound, coronary computed tomography, carotid magnetic resonance, coronary intravascular ultrasound, and coronary optical coherence tomography. Overall, all meta-analyses showed significant atherosclerotic plaque regression with lipid-lowering therapy, with the most notable effects on echogenicity, lipid-rich necrotic core volume, wall/plaque volume, dense calcium volume, and fibrous cap thickness. Significant interactions were found with concomitant changes in low density lipoprotein cholesterol, high density lipoprotein cholesterol, and C-reactive protein levels, and with ethnicity. Atherosclerotic plaque regression and conversion to a stable phenotype is possible with intensive medical therapy and can be demonstrated in patients using a variety of non-invasive and invasive imaging modalities.