Impact of Lipoprotein(a) Level on Low-Density Lipoprotein Cholesterol- or Apolipoprotein B-Related Risk of Coronary Heart Disease.

BACKGROUND: Conventional low-density lipoprotein cholesterol (LDL-C) quantification includes cholesterol attributable to lipoprotein(a) (Lp(a)-C) due to their overlapping densities. OBJECTIVES: The purposes of this study were to compare the association between LDL-C and LDL-C corrected for Lp(a)-C (LDLLp(a)corr) with incident coronary heart disease (CHD) in the general population and to investigate whether concomitant Lp(a) values influence the association of LDL-C or apolipoprotein B (apoB) with coronary events. METHODS: Among 68,748 CHD-free subjects at baseline LDLLp(a)corr was calculated as "LDL-C-Lp(a)-C," where Lp(a)-C was 30% or 17.3% of total Lp(a) mass. Fine and Gray competing risk-adjusted models were applied for the association between the outcome incident CHD and: 1) LDL-C and LDLLp(a)corr in the total sample; and 2) LDL-C and apoB after stratification by Lp(a) mass (≥/<90th percentile). RESULTS: Similar risk estimates for incident CHD were found for LDL-C and LDL-CLp(a)corr30 or LDL-CLp(a)corr17.3 (subdistribution HR with 95% CI) were 2.73 (95% CI: 2.34-3.20) vs 2.51 (95% CI: 2.15-2.93) vs 2.64 (95% CI: 2.26-3.10), respectively (top vs bottom fifth; fully adjusted models). Categorization by Lp(a) mass resulted in higher subdistribution HRs for uncorrected LDL-C and incident CHD at Lp(a) ≥90th percentile (4.38 [95% CI: 2.08-9.22]) vs 2.60 [95% CI: 2.21-3.07]) at Lp(a) <90th percentile (top vs bottom fifth; Pinteraction0.39). In contrast, apoB risk estimates were lower in subjects with higher Lp(a) mass (2.43 [95% CI: 1.34-4.40]) than in Lp(a) <90th percentile (3.34 [95% CI: 2.78-4.01]) (Pinteraction0.49). CONCLUSIONS: Correction of LDL-C for its Lp(a)-C content provided no meaningful information on CHD-risk estimation at the population level. Simple categorization of Lp(a) mass (≥/<90th percentile) influenced the association between LDL-C or apoB with future CHD mostly at higher Lp(a) levels.

Assessing the relationship between lipoprotein(a) levels and blood pressure among hypertensive patients beyond conventional measures. An observational study.

High lipoprotein(a) (Lp(a)) levels are associated with an increased risk of arterial hypertension (AHT) and atherosclerotic cardiovascular disease. However, little is known about the detailed profile of AHT based on Lp(a) levels. This observational study focused on elucidating the relationship between Lp(a) concentrations and specific indices obtained from 24-h ambulatory blood pressure (BP) monitoring in hypertensive patients over 18 years of age. We gathered and analyzed data on BP indices along with demographic, epidemiological, clinical, and laboratory variables from 227 hypertensive patients, median age 56 years, including 127 women (56%). After comparing hypertensive patients with Lp(a) levels above and below 125 nmol/L, we found that a 10 mmHg increase in nocturnal systolic BP and all pulse pressure indices (24-h, daytime, and night-time) was associated with an increased risk of high Lp(a) levels by more than 20% and 40%, respectively. Similarly, each 10% increase in the area under the function over time of nocturnal diastolic BP dipping was associated with more than a 30% decrease in the odds of belonging to the elevated Lp(a) levels category. Additionally, Lp(a) levels above 125 nmol/L were associated with higher 24-h, daytime, and night-time systolic BP and pulse pressure load. The relationship between Lp(a) and AHT appears to extend beyond conventional BP measurements, which may be relevant given the prognostic implications of nocturnal BP and pulse pressure indices.

Therapeutic Potential of Lipoprotein(a) Inhibitors.

Increasing evidence has implicated lipoprotein(a) [Lp(a)] in the causality of atherosclerosis and calcific aortic stenosis. This has stimulated immense interest in developing novel approaches to integrating Lp(a) into the setting of cardiovascular prevention. Current guidelines advocate universal measurement of Lp(a) levels, with the potential to influence cardiovascular risk assessment and triage of higher-risk patients to use of more intensive preventive therapies. In parallel, considerable activity has been undertaken to develop novel therapeutics with the potential to achieve selective and substantial reductions in Lp(a) levels. Early studies of antisense oligonucleotides (e.g., mipomersen, pelacarsen), RNA interference (e.g., olpasiran, zerlasiran, lepodisiran) and small molecule inhibitors (e.g., muvalaplin) have demonstrated effective Lp(a) lowering and good tolerability. These agents are moving forward in clinical development, in order to determine whether Lp(a) lowering reduces cardiovascular risk. The results of these studies have the potential to transform our approach to the prevention of cardiovascular disease.

Genetics and Pathophysiological Mechanisms of Lipoprotein(a)-Associated Cardiovascular Risk.

Elevated lipoprotein(a) is a genetically transmitted codominant trait that is an independent risk driver for cardiovascular disease. Lipoprotein(a) concentration is heavily influenced by genetic factors, including LPA kringle IV-2 domain size, single-nucleotide polymorphisms, and interleukin-1 genotypes. Apolipoprotein(a) is encoded by the LPA gene and contains 10 subtypes with a variable number of copies of kringle -2, resulting in >40 different apolipoprotein(a) isoform sizes. Genetic loci beyond LPA, such as APOE and APOH, have been shown to impact lipoprotein(a) levels. Lipoprotein(a) concentrations are generally 5% to 10% higher in women than men, and there is up to a 3-fold difference in median lipoprotein(a) concentrations between racial and ethnic populations. Nongenetic factors, including menopause, diet, and renal function, may also impact lipoprotein(a) concentration. Lipoprotein(a) levels are also influenced by inflammation since the LPA promoter contains an interleukin-6 response element; interleukin-6 released during the inflammatory response results in transient increases in plasma lipoprotein(a) levels. Screening can identify elevated lipoprotein(a) levels and facilitate intensive risk factor management. Several investigational, RNA-targeted agents have shown promising lipoprotein(a)-lowering effects in clinical studies, and large-scale lipoprotein(a) testing will be fundamental to identifying eligible patients should these agents become available. Lipoprotein(a) testing requires routine, nonfasting blood draws, making it convenient for patients. Herein, we discuss the genetic determinants of lipoprotein(a) levels, explore the pathophysiological mechanisms underlying the association between lipoprotein(a) and cardiovascular disease, and provide practical guidance for lipoprotein(a) testing.

Lipoprotein(a): Are we ready for large-scale clinical trials?

Cardiovascular diseases (CVD) are currently the most important disease threatening human health, which may be due to the high incidence of risk factors including hyperlipidemia. With the deepening of research on lipoprotein, lipoprotein (a) [Lp(a)] has been shown to be an independent risk factor for atherosclerotic cardiovascular diseases and calcified aortic valve stenosis and is now an unaddressed "residual risk" in current CVD management. Accurate measurement of Lp(a) concentration is the basis for diagnosis and treatment of high Lp(a). This review summarized the Lp(a) structure, discussed the current problems in clinical measurement of plasma Lp(a) concentration and the effects of existing lipid-lowering therapies on Lp(a).

Identifying People at High Risk for Severe Aortic Stenosis: Aortic Valve Calcium Versus Lipoprotein(a) and Low-Density Lipoprotein Cholesterol.

BACKGROUND: Aortic valve calcification (AVC), Lp(a) [lipoprotein(a)], and low-density lipoprotein cholesterol (LDL-C) are associated with severe aortic stenosis (AS). We aimed to determine which of these risk factors were most strongly associated with the risk of incident severe AS. METHODS: A total of 6792 participants from the MESA study (Multi-Ethnic Study of Atherosclerosis) had computed tomography-quantified AVC, Lp(a), and LDL-C values at MESA visit 1 (2000-2002). We calculated the absolute event rate of incident adjudicated severe AS per 1000 person-years and performed multivariable adjusted Cox proportional hazards regression. RESULTS: The mean age was 62 years old, and 47% were women. Over a median 16.7-year follow-up, the rate of incident severe AS increased exponentially with higher AVC, regardless of Lp(a) or LDL-C values. Participants with AVC=0 had a very low rate of severe AS even with elevated Lp(a) ≥50 mg/dL (<0.1/1000 person-years) or LDL-C ≥130 mg/dL (0.1/1000 person-years). AVC >0 was strongly associated with severe AS when Lp(a) <50 mg/dL hazard ratio (HR) of 33.8 (95% CI, 16.4-70.0) or ≥50 mg/dL HR of 61.5 (95% CI, 7.7-494.2) and when LDL-C <130 mg/dL HR of 31.1 (95% CI, 14.4-67.1) or ≥130 mg/dL HR of 50.2 (95% CI, 13.2-191.9). CONCLUSIONS: AVC better identifies people at high risk for severe AS compared with Lp(a) or LDL-C, and people with AVC=0 have a very low long-term rate of severe AS regardless of Lp(a) or LDL-C level. These results suggest AVC should be the preferred prognostic risk marker to identify patients at high risk for severe AS, which may help inform participant selection for future trials testing novel strategies to prevent severe AS.

[Distribution and influencing factors of lipoprotein (a) levels in non-arteriosclerotic cardiovascular disease population in China].

Objective: To describe the distribution of lipoprotein (a) [Lp(a)] levels in non-arteriosclerotic cardiovascular disease (ASCVD) population in China and explore its influencing factors. Methods: This study was based on a nested case-control study in the CKB study measured plasma biomarkers. Lp(a) levels was measured using a polyclonal antibody-based turbidimetric assay certified by the reference laboratory and ≥75.0 nmol/L defined as high Lp(a). Multiple logistic regression model was used to examine the factors related to Lp(a) levels. Results: Among the 5 870 non-ASCVD population included in the analysis, Lp(a) levels showed a right-skewed distribution, with a M (Q1, Q3) of 17.5 (8.8, 43.5) nmol/L. The multiple logistic regression analysis found that female was associated with high Lp(a) (OR=1.23, 95%CI: 1.05-1.43). The risk of increased Lp(a) levels in subjects with abdominal obesity was significantly reduced (OR=0.68, 95%CI: 0.52-0.89). As TC, LDL-C, apolipoprotein A1(Apo A1), and apolipoprotein B(Apo B) levels increased, the risk of high Lp(a) increased, with OR (95%CI) for each elevated group was 2.40 (1.76-3.24), 2.68 (1.36-4.93), 1.29 (1.03-1.61), and 1.65 (1.27-2.13), respectively. The risk of high Lp(a) was reduced in the HDL-C lowering group with an OR (95%CI) of 0.76 (0.61-0.94). In contrast, an increase in TG levels and the ratio of Apo A1/Apo B(Apo A1/B) was negatively correlated with the risk of high Lp(a), with OR (95%CI) of 0.73 (0.60-0.89) for elevated triglyceride group, and OR (95%CI) of 0.60 (0.50-0.72) for the Apo A1/B ratio increase group (linear trend test P≤0.001 except for Apo A1). However, no correlation was found between Lp(a) levels and lifestyle factors such as diet, smoking, and physical activity. Conclusions: Lp(a) levels were associated with sex and abdominal obesity, but less with lifestyle behaviors.

Lipoprotein(a), Oxidized Phospholipids, and Progression to Symptomatic Heart Failure: The CASABLANCA Study.

BACKGROUND: Higher lipoprotein(a) and oxidized phospholipid concentrations are associated with increased risk for coronary artery disease and valvular heart disease. The role of lipoprotein(a) or oxidized phospholipid as a risk factor for incident heart failure (HF) or its complications remains uncertain. METHODS AND RESULTS: A total of 1251 individuals referred for coronary angiography in the Catheter Sampled Blood Archive in Cardiovascular Diseases (CASABLANCA) study were stratified on the basis of universal definition of HF stage; those in stage A/B (N=714) were followed up for an average 3.7 years for incident stage C/D HF or the composite of HF/cardiovascular death. During follow-up, 105 (14.7%) study participants in stage A/B progressed to symptomatic HF and 57 (8.0%) had cardiovascular death. In models adjusted for multiple HF risk factors, including severe coronary artery disease and aortic stenosis, individuals with lipoprotein(a) ≥150 nmol/L were at higher risk for progression to symptomatic HF (hazard ratio [HR], 1.90 [95% CI, 1.15-3.13]; P=0.01) or the composite of HF/cardiovascular death (HR, 1.71 [95% CI, 1.10-2.67]; P=0.02). These results remained significant after further adjustment of the model to include prior myocardial infarction (HF: HR, 1.89, P=0.01; HF/cardiovascular death: HR, 1.68, P=0.02). Elevated oxidized phospholipid concentrations were similarly associated with risk, particularly when added to higher lipoprotein(a). In Kaplan-Meier analyses, individuals with stage A/B HF and elevated lipoprotein(a) had shorter time to progression to stage C/D HF or HF/cardiovascular death (both log-rank P<0.001). CONCLUSIONS: Among individuals with stage A or B HF, higher lipoprotein(a) and oxidized phospholipid concentrations are independent risk factors for progression to symptomatic HF or cardiovascular death. REGISTRATION: URL: https://wwwclinicaltrials.gov; Unique identifier: NCT00842868.

Associations of lipids and lipid-modifying drug target genes with atrial fibrillation risk based on genomic data.

BACKGROUND: The causal associations of lipids and the drug target genes with atrial fibrillation (AF) risk remain obscure. We aimed to investigate the causal associations using genetic evidence. METHODS: Mendelian randomization (MR) analyses were conducted using summary-level genome-wide association studies (GWASs) in European and East Asian populations. Lipid profiles (low-density lipoprotein cholesterol, triglyceride, and lipoprotein[a]) and lipid-modifying drug target genes (3-hydroxy-3-methylglutaryl-CoA reductase, proprotein convertase subtilisin/kexin type 9, NPC1-like intracellular cholesterol transporter 1, apolipoprotein C3, angiopoietin-like 3, and lipoprotein[a]) were used as exposures. AF was used as an outcome. The inverse variance weighted method was applied as the primary method. Summary-data-based Mendelian randomization analyses were performed for further validation using expression quantitative trait loci data. Mediation analyses were conducted to explore the indirect effect of coronary heart disease. RESULTS: In the European population, MR analyses demonstrated that elevated levels of lipoprotein(a) increased AF risk. Moreover, analyses focusing on drug targets revealed that the genetically proxied target gene LPA, which simulates the effects of drug intervention by reducing lipoprotein(a), exhibited an association with AF risk. This association was validated in independent datasets. There were no consistent and significant associations observed for other traits when analyzed in different datasets. This finding was also corroborated by Summary-data-based Mendelian randomization analyses between LPA and AF. Mediation analyses revealed that coronary heart disease plays a mediating role in this association. However, in the East Asian population, no statistically significant evidence was observed to support these associations. CONCLUSIONS: This study provided genetic evidence that Lp(a) may be a causal factor for AF and that LPA may represent a promising pharmacological target for preventing AF in the European population.

Serum Lipoprotein(a) Levels as a Predictor of Aortic Stiffness in Patients on Long-Term Peritoneal Dialysis.

BACKGROUND Lipoprotein (a) [Lp(a)] is associated with atherosclerosis and cardiovascular mortality in patients with kidney failure. Aortic stiffness (AS), measured primarily by carotid-femoral pulse wave velocity (cfPWV), reflects vascular aging and precedes end-organ failure. This study aimed to evaluate the association between serum Lp(a) levels and cfPWV in patients undergoing peritoneal dialysis (PD). MATERIAL AND METHODS In this cross-sectional study, which included 148 patients with long-term PD for end-stage kidney failure, cfPWV was measured using a cuff-based method. AS was defined as a cfPWV exceeding 10 m/s, and an enzyme-linked immunosorbent assay was used to determine serum Lp(a) levels. Univariate and multivariate regression analyses were performed to identify the clinical correlates of AS. RESULTS There were 32 (21.6%) patients diagnosed with AS. Based on the multivariate logistic regression analysis, the odds ratio for AS was 1.007 (95% confidence interval, 1.003-1.011; P=0.001) for every 1 mg/L increase in Lp(a) levels. Multivariate linear regression analysis showed that Lp(a) (P<0.001), age (P=0.003), waist circumference (P=0.008), systolic blood pressure (P=0.010), and diabetes mellitus (P<0.001) were positively associated with cfPWV. The area under the receiver operating characteristic curve for Lp(a) in differentiating AS from non-AS was 0.770 (95% confidence interval, 0.694-0.835; P<0.0001). CONCLUSIONS Serum Lp(a) level was independently associated with cfPWV and AS in patients with PD.

Influence of Dulaglutide on Serum Biomarkers of Atherosclerotic Plaque Instability: An Interventional Analysis of Cytokine Profiles in Diabetic Subjects-A Pilot Study.

Background and Objectives: The rise in global diabetes cases, reaching a staggering 529 million in 2021 from 108 million in 1980, underscores the urgency of addressing its complications, notably macrovascular ones like coronary artery, cerebrovascular, and peripheral artery diseases, which contribute to over 50% of diabetes mortality. Atherosclerosis, linked to hyperglycemia-induced endothelial dysfunction, is pivotal in cardiovascular disease development. Cytokines, including pentraxin 3 (PTX3), copeptin, lipoprotein(a) [Lp(a)], and matrix metalloproteinase-9 (MMP-9), influence atherosclerosis progression and plaque vulnerability. Inhibiting atherosclerosis progression is crucial, especially in diabetic individuals. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs), increasingly used for type 2 diabetes, show promise in reducing the cardiovascular risk, sparking interest in their effects on atherogenesis. This study sought to examine the effects of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on biomarkers that indicate the instability of atherosclerotic plaques. These biomarkers include pentraxin 3 (PTX3), copeptin (CPC), matrix metalloproteinase-9 (MMP-9), and lipoprotein(a) [Lp(a)]. Materials and Methods: A total of 34 participants, ranging in age from 41 to 81 years (with an average age of 61), who had been diagnosed with type 2 diabetes mellitus (with a median HbA1c level of 8.8%), dyslipidemia, and verified atherosclerosis using B-mode ultrasonography, were included in the study. All subjects were eligible to initiate treatment with a GLP-1 RA-dulaglutide. Results: Significant reductions in anthropometric parameters, blood pressure, fasting glucose levels, and HbA1c levels were observed posttreatment. Moreover, a notable decrease in biochemical markers associated with atherosclerotic plaque instability, particularly PTX3 and MMP-9 (p < 0.001), as well as Lp(a) (p < 0.05), was evident following the GLP-1 RA intervention. Conclusions: These findings underscore the potential of GLP-1 RAs in mitigating atherosclerosis progression and plaque vulnerability, thus enhancing cardiovascular outcomes in individuals with type 2 diabetes mellitus.

Lipoprotein (a) concentration as a risk factor for ischaemic stroke and its subtypes.

AIM OF THE STUDY: To investigate the relationship between serum lipoprotein (a) [Lp(a)] concentration and the risk of ischaemic stroke (IS) and its subtypes. CLINICAL RATIONALE FOR THE STUDY: Lp(a) plays a role in atherogenic, pro-thrombotic, and antifibrinolytic processes. Elevated plasma Lp(a) is a strong independent risk factor for the development and progression of atherosclerotic disease. The association between lipoproteins and IS is more complex than that reported for cardiovascular diseases, with inconsistent and contradictory results from epidemiological studies. MATERIAL AND METHODS: 231 patients with acute IS (defined as cases) and 163 age- and sex-matched control subjects were included in this prospective case-control study. Demographic and clinical variables (i.e. age, sex, smoking, presence of chronic diseases and concomitant medication) and laboratory data (i.e. concentrations of total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, triglycerides, Lp(a), apolipoprotein A1, apolipoprotein B) were recorded. RESULTS: The mean age and the percentage of men did not significantly differ between groups. Compared to controls, there was a significantly higher percentage of cases reported with concomitant diseases: diabetes mellitus, myocardial infarction, ischaemic heart disease, peripheral arterial disease, and atrial fibrillation. The study showed a significantly higher serum Lp(a) concentration in cases than in control subjects (81.81 nmol/L [c.32.7 mg/dL] vs. 59.75 nmol/L [c.23.9 mg/dL]; p = 0.036) and found an association between Lp(a) levels stratified by quartiles and the risk for ischaemic stroke (Q1 [Lp(a) < 13 nmol/L] vs. Q4 [Lp(a) > 117 nmol/L]: OR 2.23; 95% CI 1.23-4.03; p = 0.008). A subgroup analysis based on the TOAST classification of IS also showed a significant association between Lp(a) value of more than 75 nmol/L (30 mg/dL) and the risk of large-artery atherosclerosis stroke compared to the controls (OR 2.4; 95% CI 1.39-3.93; p = 0.001), as well as a statistically non-significant association with other subtypes of IS. The influence of Lp(a) remained significant even after adjusting for established risk factors for IS (OR 1.99; 95% CI 1.05-3.76; p = 0.04; respectively for the large-artery atherosclerotic subtype: OR 2.54; 95% CI 1.39-4.67; p = 0.003). CONCLUSION: We found that Lp(a) is an independent risk factor for ischaemic stroke, and for the large-artery atherosclerotic subtype of ischaemic stroke.

Comparative Analysis of Atherogenic Lipoproteins L5 and Lp(a) in Atherosclerotic Cardiovascular Disease.

PURPOSE OF REVIEW: Low-density lipoprotein (LDL) poses a risk for atherosclerotic cardiovascular disease (ASCVD). As LDL comprises various subtypes differing in charge, density, and size, understanding their specific impact on ASCVD is crucial. Two highly atherogenic LDL subtypes-electronegative LDL (L5) and Lp(a)-induce vascular cell apoptosis and atherosclerotic changes independent of plasma cholesterol levels, and their mechanisms warrant further investigation. Here, we have compared the roles of L5 and Lp(a) in the development of ASCVD. RECENT FINDINGS: Lp(a) tends to accumulate in artery walls, promoting plaque formation and potentially triggering atherosclerosis progression through prothrombotic or antifibrinolytic effects. High Lp(a) levels correlate with calcific aortic stenosis and atherothrombosis risk. L5 can induce endothelial cell apoptosis and increase vascular permeability, inflammation, and atherogenesis, playing a key role in initiating atherosclerosis. Elevated L5 levels in certain high-risk populations may serve as a distinctive predictor of ASCVD. L5 and Lp(a) are both atherogenic lipoproteins contributing to ASCVD through distinct mechanisms. Lp(a) has garnered attention, but equal consideration should be given to L5.

Exploring the Interplay between Diabetes and Lp(a): Implications for Cardiovascular Risk.

PURPOSE OF REVIEW: The objective of this manuscript is to review and describe the relationship between Lp(a) and diabetes, exploring both their association and synergy as cardiovascular risk factors, while also describing the current evidence regarding the potential connection between low levels of Lp(a) and the presence of diabetes. RECENT FINDINGS: Epidemiological studies suggest a potential relationship between low to very low levels of Lp(a) and diabetes. Lipoprotein(a), or Lp(a), is an intriguing lipoprotein of genetic origin, yet its biological function remains unknown. Elevated levels of Lp(a) are associated with an increased risk of cardiovascular atherosclerosis, and coexisting diabetes status confers an even higher risk. On the other hand, epidemiological and genetic studies have paradoxically suggested a potential relationship between low to very low levels of Lp(a) and diabetes. While new pharmacological strategies are being developed to reduce Lp(a) levels, the dual aspects of this lipoprotein's behavior need to be elucidated in the near future.