The Hypercholesterolemia Paradox in Percutaneous Coronary Intervention: An Analysis of a Multicenter PCI Registry

Low LDL-cholesterol drives the risk of bleeding in patients treated with aspirin: A 15-year study in a real-world large population

We aimed to investigate the link between LDL cholesterol (LDL-C) levels and hemorrhage risk over an extended period, both in subjects taking aspirin and in individuals not receiving any antiplatelet agent. We calculated the predicted adjusted relative hazard of bleeding by LDL-C concentration for the whole cohort and the aspirin-treated subgroup. The study included 39,784 individuals with a mean follow-up of 14.9 years, totaling over 500,000 patient-years. Across the cohort, 3380 bleeding events were reported, with a higher incidence in patients with LDL-C < 70 mg/dL compared to those with LDL-C ≥ 70 mg/dL (9.9 % vs 8.4 %). In aspirin-treated patients, multivariable analysis revealed that hemorrhagic events were significantly associated with aging, male sex, body mass index, hypertension, and LDL-C < 70 mg/dL. These patients had a significantly lower event-free survival probability if their LDL-C was < 70 mg/dL compared to ≥ 70 mg/dL. Low LDL-C values were a significant risk factor (HR >1) while higher LDL-C values were protective (HR <1). A stepwise increase of 10 mg/dL in LDL-C from < 30 to ≥ 200 mg/dL was associated with a decreasing trend for bleeding events in both the entire cohort and the aspirin-treated subgroup. This is the first report specifically addressing the relationship between LDL-C levels and bleeding risk in a population receiving low-intensity antithrombotic therapy. Our data demonstrate that in patients taking aspirin, LDL-C levels below 70 mg/dL significantly increase the risk of bleeding, with major implications for long-term cardiovascular risk management.

Low HDL Cholesterol is Associated with Reduced Bleeding Risk in Patients who Underwent PCI: Findings from the PRACTICE Study

BACKGROUND

 We sought to examine the dose-response relationship between high-density lipoprotein cholesterol (HDL-C) and bleeds in coronary artery disease (CAD) patients who underwent percutaneous coronary intervention (PCI).

METHODS

 All the 15,250 participants were from the Personalized Antiplatelet Therapy According to CYP2C19 Genotype in Coronary Artery Disease (PRACTICE) study, which is a large, single-center, prospective cohort study based on case records and a follow-up registry performed in the First Affiliated Hospital of Xinjiang Medical University from December 2016 to October 2021. We divided all the patients into five groups according to their HDL-C levels: the ≤35 mg/dL group (n = 4,732), 35 to 45 mg/dL group (n = 6,049), 45 to 55 mg/dL group (n = 2,826), 55 and 65 mg/dL group (n = 1,117), and >65 mg/dL group (n = 526). The incidence of bleeds, mortality, ischemic events, and net adverse clinical events (NACEs) among the five groups was compared.

RESULTS

 A total of 713 bleeds, 1,180 ischemic events, 456 deaths, and 1,893 NACEs were recorded during the up to 60-month follow-up period. After adjusting for confounders, we observed a nonlinear relation for bleeds, with the highest risk at intermediate HDL-C levels (45-55 mg/dL). We also identified a dose-response relationship for ischemic events. A threshold value of HDL-C ≤35 mg/dL (adjusted hazard ratio = 0.560, 95% confidence interval: 0.360-0.872, p = 0.010) was associated with a decreased risk for bleeds in the multivariable Cox regression model. The results were consistent in multiple sensitivity analyses and propensity score-matching analysis.

CONCLUSION

 In the present study, a nonlinear association was identified between HDL-C levels and bleeds in CAD patients who underwent PCI, with a higher risk at intermediate levels. However, further multicenter studies are warranted.

Remnant cholesterol but not LDL cholesterol is associated with 5-year bleeding following percutaneous coronary intervention

This study was aimed to investigate the association between remnant cholesterol (RC) and low-density lipoprotein cholesterol (LDL-C) concentrations and long-term bleeding. A total of 10,724 consecutive patients who underwent percutaneous coronary intervention in 2013 were prospectively enrolled. During a median follow-up of 5.1 years, 411 bleeding events and 42 intracranial hemorrhages (ICH) were recorded. The findings revealed that lower RC concentrations were independently associated with an increased risk of long-term bleeding events (continuous RC hazard ratio [HR]: 0.47, 95% confidence interval [CI]: 0.26-0.85; Q4 vs. Q1 HR: 0.66, 95% CI: 0.45-0.98), whereas lower LDL-C concentrations did not show a similar association. Additionally, a non-linear relationship was observed between RC concentrations and the risk of ICH (P for non-linear trend = 0.014), but no such relationship was found for LDL-C concentrations. These results provided insights into the safety of LDL-C-lowering therapy and emphasized the significance of RC concentrations in lipid management.

Antithrombotic therapy and bleeding risk in the era of aggressive lipid-lowering: current evidence, clinical implications, and future perspectives

ABSTRACT

The clinical efficacy of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) in reducing major cardiovascular adverse events related to atherosclerotic cardiovascular disease (ASCVD) has been well established in recent large randomized outcome trials. Although the cardiovascular and all-cause mortality benefit of PCSK9i remains inconclusive, current cholesterol management guidelines have been modified toward more aggressive goals for lowering low-density lipoprotein cholesterol (LDL-C). Consequently, the emerging concept of "the lower the better" has become the paradigm of ASCVD prevention. However, there is evidence from observational studies of a U-shaped association between baseline LDL-C levels and all-cause mortality in population-based cohorts. Among East Asian populations, low LDL-C was associated with an increased risk for hemorrhagic stroke in patients not on antithrombotic therapy. Accumulating evidence showed that low LDL-C was associated with an enhanced bleeding risk in patients on dual antiplatelet therapy following percutaneous coronary intervention. Additionally, low LDL-C was associated with a higher risk for incident atrial fibrillation and thereby, a possible increase in the risk for intracranial hemorrhage after initiation of anticoagulation therapy. The mechanism of low-LDL-C-related bleeding risk has not been fully elucidated. This review summarizes recent evidence of low-LDL-C-related bleeding risk in patients on antithrombotic therapy and discusses potential measures for reducing this risk, underscoring the importance of carefully weighing the pros and cons of aggressive LDL-C lowering in patients on antithrombotic therapy.

LDL cholesterol levels and in-hospital bleeding in patients on high-intensity antithrombotic therapy: findings from the CCC-ACS project

AIMS 

Emerging evidence has linked cholesterol metabolism with platelet responsiveness. We sought to examine the dose-response relationship between low-density lipoprotein cholesterol (LDL-C) and major in-hospital bleeds in acute coronary syndrome (ACS) patients.

METHODS AND RESULTS 

Among 42 378 ACS patients treated with percutaneous coronary intervention (PCI) enrolled in 240 hospitals in the Improving Care for Cardiovascular Disease in China-ACS project from 2014 to 2019, a total of 615 major bleeds, 218 ischaemic events, and 337 deaths were recorded. After controlling for baseline variables, a non-linear relationship was observed for major bleeds, with the higher risk at lower LDL-C levels. No dose-response relationship was identified for ischaemic events and mortality. A threshold value of LDL-C <70 mg/dL was associated with an increased risk for major bleeds (adjusted odds ratio: 1.49; 95% confidence interval: 1.21-1.84) in multivariable-adjusted logistic regression models and in propensity score-matched cohorts. The results were consistent in multiple sensitivity analyses. Among ticagrelor-treated patients, the LDL-C threshold for increased bleeding risk was observed at <88 mg/dL, whereas for clopidogrel-treated patients, the threshold was <54 mg/dL. Across a full spectrum of LDL-C levels, the treatment effect size associated with ticagrelor vs. clopidogrel on major bleeds favoured clopidogrel at lower LDL-C levels, but no difference at higher LDL-C levels.

CONCLUSIONS 

In a nationwide ACS registry, a non-linear association was identified between LDL-C levels and major in-hospital bleeds following PCI, with the higher risk at lower levels. As the potential for confounding may exist, further studies are warranted.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02306616.

Revisiting the lipid paradox in ST-elevation myocardial infarction in the Chinese population: findings from the CCC-ACS project

AIMS

Previous observations revealed a negative association between low-density lipoprotein cholesterol (LDL-C) and clinical outcomes following myocardial infarction, i.e., the lower level the higher mortality, which was referred to as lipid paradox. We sought to re-evaluate this association in ST-elevation myocardial infarction (STEMI) in contemporary practice.

METHODS AND RESULTS

We examined the association between admission LDL-C and in-hospital mortality among 44 563 STEMI patients enrolled from 2014 to 2019 in a nationwide registry in China. A total of 43 covariates, which were temporally classified into the following three domains were used for adjustment: (i) pre-admission characteristics; (ii) percutaneous coronary intervention (PCI)-related variables; and (iii) other in-hospital medications. In-hospital mortality was 2.01% (897/44 563). When no covariate adjustment was performed, an inversely 'J-shaped' curve was observed between admission LDL-C levels and in-hospital mortality by restricted cubic spline in logistic regression, with a threshold value of <75 mg/dL that associated with increased risk for in-hospital mortality. However, a gradual attenuation for this association was noted when step-wise adjustments were performed, with the threshold values for LDL-C decreasing from 75 mg/dL to 70 mg/dL after accounting for pre-admission characteristics, further to 65 mg/dL after accounting for PCI-related variables, and finally to no statistical association after further adjustment for other in-hospital medications.

CONCLUSIONS

In a nationwide registry in China, our findings do not support the lipid paradox in terms of in-hospital mortality in STEMI patients in contemporary practice. Previous findings in this scenario are possibly due to inadequate control for confounders.