ApoB and non-HDL cholesterol versus LDL cholesterol for ischemic stroke risk

Cardiovascular Risk Estimation and Stratification Among Individuals with Hypercholesterolemia

PURPOSE OF THE REVIEW

This review aims to assess the variability in considering hypercholesterolemia for cardiovascular risk stratification in the general population. Recent literature on the integration of hypercholesterolemia into clinical risk scores and its interaction with other risk factors will be explored.

RECENT FINDINGS

The impact of hypercholesterolemia on risk estimation varies among different cardiovascular risk calculators. Elevated lipid levels during early life stages contribute to atherosclerotic plaque development, influencing disease severity despite later treatment initiation. The interplay between low-density lipoprotein cholesterol (LDLc), inflammatory markers and non-LDL lipid parameters enhances cardiovascular risk stratification. Studies have also examined the role of coronary artery calcium (CAC) score as a negative risk marker in populations with severe hypercholesterolemia. Furthermore, polygenic risk scores (PRS) may aid in diagnosing non-monogenic hypercholesterolemia, refining cardiovascular risk stratification and guiding lipid-lowering therapy strategies. Understanding the heterogeneity in risk estimation and the role of emerging biomarkers and imaging techniques is crucial for optimizing cardiovascular risk prediction and guiding personalized treatment strategies in individuals with hypercholesterolemia.

Low Remnant Cholesterol and In-Hospital Bleeding Risk After Ischemic Stroke or Transient Ischemic Attack

BACKGROUND

Bleeding risk brought by intensive lipid-lowering therapy and low low-density lipoprotein cholesterol is concerning, while evidence regarding the relationship between remnant cholesterol and bleeding is frightening. This study aimed to investigate the association between remnant cholesterol at admission and an in-hospital bleeding event after acute ischemic stroke or transient ischemic attack (TIA).

METHODS AND RESULTS

A total of 3222 eligible patients admitted to Shanghai Huashan Hospital between 2015 and 2021 with complete lipid data were analyzed. Patients were classified into low (<20.0 mg/dL), moderate (20.0-29.9 mg/dL), and high (≥30 mg/dL) groups by remnant cholesterol. The mean age of patients was 63.0± 13.1 years, including 2301 (71.4%) men and 651 (20.2%) with TIA. The median (interquartile range) of remnant cholesterol was 18.6 (13.5-25.9) mg/dL. After adjustment for confounding variables, patients with low remnant cholesterol had a higher risk of bleeding events (odds ratio, 2.56 [95% CI, 1.12-6.67]) than those with moderate remnant cholesterol. The high remnant cholesterol group was not significantly associated with bleeding risk. Combined assessment of low-density lipoprotein cholesterol and remnant cholesterol further identified patients with the highest risk of bleeding events.

CONCLUSIONS

Low remnant cholesterol levels were associated with bleeding events during the acute stage of ischemic stroke and TIA. The assessment of remnant cholesterol could inform the bleeding risk during hospitalization both for patients and physicians in clinical practice.

Discordance between LDL-C and apolipoprotein B is associated with large-artery-atherosclerosis ischemic stroke in patients ⩽70 years of age

BACKGROUND AND AIMS

Low density lipoprotein (LDL-C) and other atherogenic lipoproteins are coated by apolipoprotein B100 (apoB). The correlation between LDL-C and apoB is usually thight, but in some cases LDL-C underestimates apoB levels and residual cardiovascular risk. We aimed to assess if a discordance of LDL-C-levels with apoB levels is associated with LAA stroke.

METHODS

We included patients with an acute ischemic stroke from two prospective studies enrolled at the University Hospital Bern, Basel and Zurich, Switzerland. LDL-C and apoB were measured within 24 h of symptom onset. By linear regression, for each LDL-C, we computed the expected apoB level assuming a perfect correlation. Higher-than-expected apoB was defined as apoB level being in the upper residual tertile.

RESULTS

Overall, we included 1783 patients, of which 260 had a LAA stroke (15%). In the overall cohort, higher-than-expected apoB values were not associated with LAA. However, a significant interaction with age was present. Among the 738 patients ⩽70 years of age, a higher-than-expected apoB was more frequent in patients with LAA- versus non LAA-stroke (48% vs 36%, p = 0.02). In multivariate analysis, a higher-than-expected apoB was associated with LAA stroke (aOR = aOR 2.48, 95%CI 1.14-5.38). Among those aged ⩽70 years and with LAA, 11.7% had higher than guideline-recommended apoB despite LDL-C ⩽ 1.8 mmol/L (<70 mg/dl), compared to 5.9% among patients with other stroke etiologies (p = 0.04). A triglyceride cut-off of ⩾0.95 mmol/L had, in external validation, a sensitivity of 71% and specificity of 52% for apoB ⩾ 0.65 g/L among patients with LDL-C <1.8 mmol/L.

CONCLUSIONS

Among patients aged ⩽70 years, a higher-than-expected apoB was independently associated with LAA stroke. Measuring apoB may help identify younger stroke patients potentially benefiting from intensified lipid-lowering therapy.

Exploring Genetic Associations of 3 Types of Risk Factors With Ischemic Stroke: An Integrated Bioinformatics Study

BACKGROUND

Ischemic stroke (IS) is a major cause of disability and mortality worldwide. Increasing evidence suggests a strong association between blood pressure, blood glucose, circulating lipids, and IS. Nonetheless, the genetic association of these 3 risk factors with IS remains elusive.

METHODS

We screened genetic instruments related to blood pressure, blood glucose, and circulating lipids and paired them with IS genome-wide association study data to conduct Mendelian randomization analysis. Positive Mendelian randomization findings were then subjected to colocalization analysis. Subsequently, we utilized the Gene Expression Omnibus data set to perform differential expression analysis, aiming to identify differentially expressed associated genes. We determined the importance scores of these differentially expressed associated genes through 4 machine learning models and constructed a nomogram based on these findings.

RESULTS

The combined results of the Mendelian randomization analysis indicate that blood pressure (systolic blood pressure: odds ratio [OR], 1.02 [95% CI, 1.01-1.02]; diastolic blood pressure: OR, 1.03 [95% CI, 1.03-1.04]) and some circulating lipids (low-density lipoprotein cholesterol: OR, 1.06 [95% CI, 1.01-1.12]; apoA1: OR, 0.95 [95% CI, 0.92-0.98]; apoB: OR, 1.05 [95% CI, 1.01-1.09]; eicosapentaenoic acid: OR, 2.36 [95% CI, 1.41-3.96]) have causal relationships with the risk of IS onset. We identified 73 genes that are linked to blood pressure and circulating lipids in the context of IS, and 16 are differentially expressed associated genes. FURIN, MAN2A2, HDDC3, ALDH2, and TOMM40 were identified as feature genes for constructing the nomogram that provides a quantitative prediction of the risk of IS onset.

CONCLUSIONS

This study indicates that there are causal links between blood pressure, certain circulating lipids, and the development of IS. The potential mechanisms underlying these causal relationships involve the regulation of lipid metabolism, blood pressure, DNA repair and methylation, cell apoptosis and autophagy, immune inflammation, and neuronal protection, among others.

Ischemic Brain Injury: Involvement of Lipids in the Pathophysiology of Stroke and Therapeutic Strategies

Stroke is a devastating neurological disorder that is characterized by the sudden disruption of blood flow to the brain. Lipids are essential components of brain structure and function and play pivotal roles in stroke pathophysiology. Dysregulation of lipid signaling pathways modulates key cellular processes such as apoptosis, inflammation, and oxidative stress, exacerbating ischemic brain injury. In the present review, we summarize the roles of lipids in stroke pathology in different models (cell cultures, animal, and human studies). Additionally, the potential of lipids, especially polyunsaturated fatty acids, to promote neuroprotection and their use as biomarkers in stroke are discussed.

Peripheral apolipoprotein is an independent factor for enlarged perivascular space in small vessel disease

OBJECTIVE

The purpose of this study is to the relationship between peripheral apolipoproteins and cerebral small vessel disease (CSVD) imaging markers.

METHODS

We reviewed the data of a population that above 40 years old with CSVD, while free of known dementia or acute stroke. We evaluated CSVD imaging markers, including white matter hyperintensities (WMHs), enlarged perivascular spaces (EPVS), lacunas, microbleeds by MRI scans, and measured peripheral apolipoproteins.

RESULTS

After adjusting for age, sex and vascular risk factors,1) apoB and apoB/apoA-1 were related to grade of EPVS in basal ganglia(apoB:r=0.196,p<0.001;apoB/apoA-1:r=0.208,p<0.001), apoE was related to grade of EPVS in centrum semiovale (r=0.125,p=0.040); 2) apoB(OR=1.739, 95%CI=1.357-2.061, p<0.001), apoB/apoA-1(OR=1.116, 95%CI=1.037-1.761, p=0.005) and apoE(OR=1.287, 95%CI=1.036-1.599, p=0.023) were independent factors of presence of severer EPVS in basal ganglia, apoE was an independent factor of presence of severer EPVS in centrum semiovale (OR=1.235, 95%CI=1.021-1.494, p=0.029).

CONCLUSION

Our findings demonstrated peripheral apolipoproteins, including apoB, apoB/apoA-1, and apoE, were independent factor for EPVS in CSVD.

Childhood Non-HDL Cholesterol and LDL Cholesterol and Adult Atherosclerotic Cardiovascular Events

BACKGROUND

Although low-density lipoprotein cholesterol (LDL-C) remains the primary cholesterol target in clinical practice in children and adults, non-high-density lipoprotein cholesterol (non-HDL-C) has been suggested as a more accurate measure of atherosclerotic cardiovascular disease (ASCVD) risk. We examined the associations of childhood non-HDL-C and LDL-C levels with adult ASCVD events and determined whether non-HDL-C has better utility than LDL-C in predicting adult ASCVD events.

METHODS

This prospective cohort study included 21 126 participants from the i3C Consortium (International Childhood Cardiovascular Cohorts). Proportional hazards regressions were used to estimate the risk for incident fatal and fatal/nonfatal ASCVD events associated with childhood non-HDL-C and LDL-C levels (age- and sex-specific z scores; concordant/discordant categories defined by guideline-recommended cutoffs), adjusted for sex, Black race, cohort, age at and calendar year of child measurement, body mass index, and systolic blood pressure. Predictive utility was determined by the C index.

RESULTS

After an average follow-up of 35 years, 153 fatal ASCVD events occurred in 21 126 participants (mean age at childhood visits, 11.9 years), and 352 fatal/nonfatal ASCVD events occurred in a subset of 11 296 participants who could be evaluated for this outcome. Childhood non-HDL-C and LDL-C levels were each associated with higher risk of fatal and fatal/nonfatal ASCVD events (hazard ratio ranged from 1.27 [95% CI, 1.14-1.41] to 1.35 [95% CI, 1.13-1.60] per unit increase in the risk factor z score). Non-HDL-C had better discriminative utility than LDL-C (difference in C index, 0.0054 [95% CI, 0.0006-0.0102] and 0.0038 [95% CI, 0.0008-0.0068] for fatal and fatal/nonfatal events, respectively). The discordant group with elevated non-HDL-C and normal LDL-C had a higher risk of ASCVD events compared with the concordant group with normal non-HDL-C and LDL-C (fatal events: hazard ratio, 1.90 [95% CI, 0.98-3.70]; fatal/nonfatal events: hazard ratio, 1.94 [95% CI, 1.23-3.06]).

CONCLUSIONS

Childhood non-HDL-C and LDL-C levels are associated with ASCVD events in midlife. Non-HDL-C is better than LDL-C in predicting adult ASCVD events, particularly among individuals who had normal LDL-C but elevated non-HDL-C. These findings suggest that both non-HDL-C and LDL-C are useful in identifying children at higher risk of ASCVD events, but non-HDL-C may provide added prognostic information when it is discordantly higher than the corresponding LDL-C and has the practical advantage of being determined without a fasting sample.

Non-HDL cholesterol and residual risk of cardiovascular events in patients with ischemic heart disease and well-controlled LDL cholesterol: a cohort study

Background

Identifying patients at high residual risk of atherosclerotic cardiovascular disease (ASCVD) despite statin-treatment is of paramount clinical importance. We aim to investigate if non-high-density lipoprotein cholesterol (non-HDL-C) identifies residual risk of ASCVD and death in statin-treated patients with ischemic heart disease and low-density lipoprotein cholesterol (LDL-C) ≤ 1.8 mmol/L.

Methods

Leveraging Danish regional and national registries, we identified statin-treated patients with ischemic heart disease who underwent coronary angiography (CAG) and attained LDL-C ≤ 1.8 mmol/L within a year post-CAG. Outcomes were myocardial infarction (MI), ASCVD (MI or ischemic stroke), and all-cause death occurring from one year after CAG to end of follow-up. Cox regression analyses obtained adjusted hazard ratios (HR).

Findings

Between January 1, 2011, and December 31, 2020, we included 23,641 statin-treated patients with ischemic heart disease and LDL-C ≤ 1.8 mmol/L. During median follow-up of 4.1 years (IQR 2.4-6.1), 893 (3.8%) patients developed MI, 1207 (5.1%) ASCVD, and 3054 (12.9%) patients died. For ASCVD the adjusted HRs (95% confidence interval) for non-HDL-C < 25th percentile (<1.7 mmol/L) versus 25th-74th (1.7-2.1 mmol/L), 75th-94th (2.2-2.6 mmol/L), and ≥95th (≥2.7 mmol/L) percentile were 1.1 (0.9-1.3), 1.4 (1.1-1.7), and 1.8 (1.4-2.4), and for all-cause death 1.0 (0.9-1.1), 1.2 (1.1-1.4), and 1.4 (1.2-1.7), respectively.

Interpretation

In a contemporary secondary prevention cohort of patients with well-managed LDL-C, non-HDL-C emerges as an easily accessible marker to detect patients facing high residual risk of ASCVD and death. These findings are important for preventive strategies extending beyond LDL-C targets.

Funding

Research grant from the Novo Nordisk Foundation.

Distinct effects of cholesterol profile components on amyloid and vascular burdens

BACKGROUND

Cholesterol plays important roles in β-amyloid (Aβ) metabolism and atherosclerosis. However, the relationships of plasma cholesterol levels with Aβ and cerebral small vessel disease (CSVD) burdens are not fully understood in Asians. Herein, we investigated the relationships between plasma cholesterol profile components and Aβ and CSVD burdens in a large, non-demented Korean cohort.

METHODS

We enrolled 1,175 non-demented participants (456 with unimpaired cognition [CU] and 719 with mild cognitive impairment [MCI]) aged ≥ 45 years who underwent Aβ PET at the Samsung Medical Center in Korea. We performed linear regression analyses with each cholesterol (low-density lipoprotein cholesterol [LDL-c], high-density lipoprotein cholesterol [HDL-c], and triglyceride) level as a predictor and each image marker (Aβ uptake on PET, white matter hyperintensity [WMH] volume, and hippocampal volume) as an outcome after controlling for potential confounders.

RESULTS

Increased LDL-c levels (β = 0.014 to 0.115, p = 0.013) were associated with greater Aβ uptake, independent of the APOE e4 allele genotype and lipid-lowering medication. Decreased HDL-c levels (β =  - 0.133 to - 0.006, p = 0.032) were predictive of higher WMH volumes. Increased LDL-c levels were also associated with decreased hippocampal volume (direct effect β =  - 0.053, p = 0.040), which was partially mediated by Aβ uptake (indirect effect β =  - 0.018, p = 0.006).

CONCLUSIONS

Our findings highlight that increased LDL-c and decreased HDL-c levels are important risk factors for Aβ and CSVD burdens, respectively. Furthermore, considering that plasma cholesterol profile components are potentially modified by diet, exercise, and pharmacological agents, our results provide evidence that regulating LDL-c and HDL-c levels is a potential strategy to prevent dementia.

Non-traditional lipid profiles and the risk of stroke: A systematic review and meta-analysis

AIMS

An increasing number of studies on non-traditional lipid profiles have been investigated in recent years. However, the associations between non-traditional lipid profiles and the risk of stroke remained inconsistent. Therefore, this meta-analysis aimed to evaluate the associations between non-traditional lipid profiles and the risk of stroke and clarify the dose-response relations.

DATA SYNTHESIS

We performed a systematic literature search in PubMed, Embase, and Web of Science databases until 1 November 2022 for relevant studies. Relative risks and 95% confidence intervals were pooled by random-effects or fixed-effects models. A total of 26 full-text studies with 676678 participants and 18057 stroke cases were eligible for the final study. We found a positive association between the risk of stroke and total cholesterol to high-density lipoprotein cholesterol (TC/HDL-C) ratio (RR = 1.19,95%CI = 1.00-1.40, I² = 74.6%), triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio (RR = 1.24,95%CI = 1.10-1.41, I² = 62.8%) or low-density lipoprotein cholesterol to high-density lipoprotein cholesterol (LDL-C/HDL-C) ratio (RR = 1.24, 95%CI = 1.11-1.39, I² = 49.4%). When focusing on the stroke subtype, a more significant association was observed between the risk of ischemic stroke and four non-traditional lipid profiles. In dose-response analysis, we found a linear association between TC/HDL-C ratio and the risk of stroke (RR = 1.16,95%CI = 1.07-1.26).

CONCLUSIONS

Elevated non-traditional lipid profiles were associated with an increased risk of ischemic stroke. The linear association showed the risk of stroke increased by 16% when the pooled RR of TC/HDL-C ratio per 1-unit increased.

REGISTRATION NUMBER IN PROSPERO

CRD42022321251.

Elevated LDL Triglycerides and Atherosclerotic Risk

BACKGROUND

It is unclear whether elevated low-density lipoprotein (LDL) triglycerides are associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD).

OBJECTIVES

This study tested the hypothesis that elevated LDL triglycerides are associated with an increased risk of ASCVD and of each ASCVD component individually.

METHODS

The study investigators used the Copenhagen General Population Study, which measured LDL triglycerides in 38,081 individuals with a direct automated assay (direct LDL triglycerides) and in another 30,208 individuals with nuclear magnetic resonance (NMR) spectroscopy (NMR LDL triglycerides). Meta-analyses aggregated the present findings with previously reported results.

RESULTS

During a median follow-up of 3.0 and 9.2 years, respectively, 872 and 5,766 individuals in the 2 cohorts received a diagnosis of ASCVD. Per 0.1 mmol/L (9 mg/dL) higher direct LDL triglycerides, HRs were 1.26 (95% CI: 1.17-1.35) for ASCVD, 1.27 (95% CI: 1.16-1.39) for ischemic heart disease, 1.28 (95% CI: 1.11-1.48) for myocardial infarction, 1.22 (95% CI: 1.08-1.38) for ischemic stroke, and 1.38 (95% CI: 1.21-1.58) for peripheral artery disease. Corresponding HRs for NMR LDL triglycerides were 1.26 (95% CI: 1.20-1.33), 1.33 (95% CI: 1.25-1.41), 1.41 (95% CI: 1.31-1.52), 1.13 (95% CI: 1.05-1.23), and 1.26 (95% CI: 1.10-1.43), respectively. The foregoing results were not entirely statistically explained by apolipoprotein B levels. In meta-analyses for the highest quartile vs the lowest quartile of LDL triglycerides, random-effects risk ratios were 1.50 (95% CI: 1.35-1.66) for ASCVD (4 studies; 71,526 individuals; 8,576 events), 1.62 (95% CI: 1.37-1.93) for ischemic heart disease (6 studies; 107,538 individuals; 9,734 events), 1.30 (95% CI: 1.13-1.49) for ischemic stroke (4 studies; 78,026 individuals; 4,273 events), and 1.53 (95% CI: 1.29-1.81) for peripheral artery disease (4 studies; 107,511 individuals; 1,848 events).

CONCLUSIONS

Elevated LDL triglycerides were robustly associated with an increased risk of ASCVD and of each ASCVD component individually in 2 prospective cohort studies and in meta-analyses of previous and present studies combined.

Small Dense Low-Density Lipoprotein Cholesterol and Ischemic Stroke

OBJECTIVE

For decades, it has been suggested that small dense low-density lipoprotein (sdLDL) may be particularly atherogenic. High levels of sdLDL are associated with an increased risk of ischemic heart disease; however, the association of sdLDL with ischemic stroke has not been explored in a large prospective study on the general population. We tested the hypothesis that high sdLDL cholesterol levels are associated with an increased risk of ischemic stroke.

METHODS

This prospective study included 38,319 individuals from the Copenhagen General Population Study with fresh sample measurements of sdLDL cholesterol. Median follow-up time was 3.1 years. We observed 302 and 74 ischemic and hemorrhagic strokes from baseline in 2013 to 2017 to the end of follow-up in 2018. For comparison, we included estimates for large buoyant LDL cholesterol and total LDL cholesterol.

RESULTS

Higher levels of sdLDL cholesterol were log-linearly associated with increased risk of ischemic stroke. Compared with individuals with sdLDL cholesterol in the lowest tertile (≤0.60 mmol/l; ≤23 mg/dl) the multivariable adjusted hazard ratio for ischemic stroke was 1.79 (95% confidence interval = 1.31-2.43) for the highest tertile (≥0.86 mmol/l; ≥33 mg/dl). Multivariable adjusted hazard ratios for ischemic stroke per 1 mmol/l (38.7 mg/dl) higher levels were 1.69 (1.28-2.22) for sdLDL cholesterol, 0.95 (0.78-1.16) for large buoyant LDL cholesterol, and 1.08 (0.93-1.25) for total LDL cholesterol. Hazard ratios were similar when further adjusting for body mass index (BMI) and diabetes mellitus in the biological pathway in combination with related lipids and lipoproteins.

INTERPRETATION

Higher sdLDL cholesterol levels were robustly associated with increased risk of ischemic stroke. ANN NEUROL 2023.