Prognostic value of elevated lipoprotein(a) in patients with acute coronary syndromes

Prognostic value of elevated lipoprotein (a) in patients with acute coronary syndromes: a systematic review and meta-analysis

Background

Elevated lipoprotein (a) level was recognized as an independent risk factor for significant adverse cardiovascular events in acute coronary syndrome (ACS) patients. Despite this recognition, the consensus in the literature regarding the prognostic significance of elevated lipoprotein (a) in ACS was also limited. Consequently, we conducted a thorough systematic review and meta-analysis to evaluate the prognostic relevance of elevated lipoprotein (a) level in individuals diagnosed with ACS.

Methods and results

A thorough literature review was conducted by systematically searching PubMed, Embase, and Cochrane databases until September 2023. This review specifically examined cohort studies exploring the prognostic implications of elevated lipoprotein (a) level in relation to major adverse cardiovascular events (MACE), including death, stroke, non-fatal myocardial infarction (MI), and coronary revascularization, in patients with ACS. The meta-analysis utilized aggregated multivariable hazard ratios (HR) and their respective 95% confidence intervals (CI) to evaluate prognostic implications between high and low lipoprotein (a) levels [the cut-off of high lipoprotein (a) level varies from 12.5 to 60 mg/dl]. Among 18,168 patients in the identified studies, elevated lipoprotein (a) was independently associated with increased MACE risk (HR 1.26; 95% CI: 1.17-1.35, P < 0.00001) and all-cause mortality (HR 1.36; 95% CI: 1.05-1.76, P = 0.02) in ACS patients. In summary, elevated lipoprotein (a) levels independently forecast MACE and all-cause mortality in ACS patients. Assessing lipoprotein (a) levels appears promising for risk stratification in ACS, offering valuable insights for tailoring secondary prevention strategies.

Systematic Review Registration

PROSPERO (CRD42023476543).

Lipoprotein(a) is associated with recurrent cardiovascular events in patients with coronary artery disease and prediabetes or diabetes

PURPOSE

Elevated lipoprotein(a) [Lp(a)] and diabetes mellitus (DM) are both associated with adverse events in high-risk patients with established coronary artery disease (CAD). Currently, the association between Lp(a) levels and recurrent cardiovascular (CV) events (CVEs) remained undetermined in patients with different glucose status. Therefore, this study aimed to investigate the prognostic significance of Lp(a) levels for recurrent CVEs in high-risk CAD patients who suffered from first CVEs according to different glycemic metabolism.

METHODS

We recruited 5257 consecutive patients with prior CVEs and followed up for recurrent CVEs, including CV death, non-fatal myocardial infarction (MI), and non-fatal stroke. Patients were assigned to low, medium, and high groups according to Lp(a) levels and further stratified by glucose status.

RESULTS

During a median 37-month follow-up, 225 (4.28%) recurrent CVEs occurred. High Lp(a) was independently associated with recurrent CVEs [adjusted Hazard Ratio (HR), 1.57; 95% confidence interval (CI) 1.12-2.19; P = 0.008]. When participants were classified according to Lp(a) levels and glycemic status, high Lp(a) levels were associated with an increased risk of recurrent CVEs in pre-DM (adjusted HR, 2.96; 95% CI 1.24-7.05; P = 0.014). Meanwhile, medium and high Lp(a) levels were both associated with an increased risk for recurrent CVEs in DM (adjusted HR, 3.09; 95% CI 1.30-7.34; P = 0.010 and adjusted HR, 3.13, 95% CI 1.30-7.53; P = 0.011, respectively).

CONCLUSIONS

This study demonstrated that elevated Lp(a) levels were associated with an increased recurrent CVE risk in patients with CAD, particularly among those with pre-DM and DM, indicating that Lp(a) may provide incremental value in risk stratification in this population.

Burden of elevated lipoprotein(a) among patients with atherosclerotic cardiovascular disease: Evidence from a systematic literature review and feasibility assessment of meta-analysis

BACKGROUND

Elevated lipoprotein(a) [Lp(a)] level is an independent genetic risk factor that increases the risk of atherosclerotic cardiovascular disease (ASCVD) by 2-4 fold. We aimed to report the burden of clinically relevant elevated Lp(a) in secondary prevention ASCVD population as the evaluation of such evidence is lacking.

METHODS

A systematic literature review (SLR) was conducted using Embase®, MEDLINE®, and MEDLINE® In-Process databases to identify studies reporting burden of elevated Lp(a) levels from January 1, 2010, to March 28, 2022. Full-text, English-language studies including ≥500 participants with ≥1 Lp(a) assessment were included.

RESULTS

Sixty-one studies reported clinical burden of elevated Lp(a). Of these, 25 observational studies and one clinical trial reported clinical burden of clinically relevant elevated Lp(a) levels. Major clinical outcomes included major adverse cardiovascular event (MACE; n = 20), myocardial infarction (MI; n = 11), revascularization (n = 10), stroke (n = 10), cardiovascular (CV) mortality (n = 9), and all-cause mortality (n = 10). Elevated Lp(a) levels significantly increased the risk of MACE (n = 15) and revascularization (n = 8), while they demonstrated a trend for positive association with remaining CV outcomes. Meta-analysis was not feasible for included studies due to heterogeneity in Lp(a) thresholds, outcome definitions, and patient characteristics. Three studies reported humanistic burden. Patients with elevated Lp(a) levels had higher odds of manifesting cognitive impairment (odds ratio [OR] [95% confidence interval; CI]: 1.62 [1.11-2.37]) and disability related to stroke (OR [95% CI]:1.46 [1.23-1.72)]) (n = 2). Elevated Lp(a) levels negatively correlated with health-related quality of life (R = -0.166, p = 0.014) (n = 1). A single study reported no association between elevated Lp(a) levels and economic burden.

CONCLUSIONS

This SLR demonstrated a significant association of elevated Lp(a) levels with major CV outcomes and increased humanistic burden in secondary prevention ASCVD population. These results reinforce the need to quantify and manage Lp(a) for CV risk reduction and to perform further studies to characterize the economic burden.

Lipoprotein(a) is a new prognostic factor in patients with psoriasis and coronary artery disease: a retrospective cohort study

BACKGROUND

The prognostic value of lipoprotein (Lp) (a) in patients who have suffered from coronary artery disease (CAD) has not been fully studied, and the results are inconsistent. This study was conducted to evaluate whether increased Lp(a) concentrations cause differences in clinical adverse outcomes in patients with psoriasis who have already suffered from CAD.

METHODS

This retrospective cohort study included consecutive patients with psoriasis and CAD between January 2017 and May 2022 in our hospital. The clinical records were collected, and comparisons were made between patients in the low Lp(a) and high Lp(a) groups. Cox proportional hazard analysis and log-rank tests were used to evaluate the association between variables.

RESULTS

Among 295 patients, 148 patients were in the low Lp(a) group, and 147 were in the high Lp(a) group. These two groups did not differ significantly in age, gender or body mass index. Compared with the low Lp(a) group, the levels of platelet counts (P = 0.038) and high sensitivity C reactive protein (P = 0.012) were higher in the high Lp(a) group. Patients in the high Lp(a) group had higher total cholesterol levels (P = 0.029) and lower triglyceride levels (P = 0.037). Among the whole cohort, clinical adverse events were not correlated with Lp(a) concentrations after a median follow-up of 3 years. However, in the subgroup analysis, there were significant differences in all-cause death (log rank P = 0.036) and rehospitalization (log rank P = 0.037) between the two groups in patients with diabetes; a difference in rehospitalization (log rank P = 0.042) was also found between the two groups in men.

CONCLUSIONS

In patients with psoriasis and CAD, high levels of Lp(a) were related to a poor prognosis, especially in patients with diabetes and in men. These results will provide valuable information for the risk stratification of patients with psoriasis and CAD.

Baseline Lipoprotein(a) Levels and Long-Term Cardiovascular Outcomes After Acute Myocardial Infarction

BACKGROUND

Lipoprotein(a) is a known independent risk factor for atherosclerotic cardiovascular disease. However, the prognostic impact of the baseline lipoprotein(a) levels on long-term clinical outcomes among patients with acute myocardial infarction remain unclear.

METHODS

We analyzed 1,908 patients with acute myocardial infarction from November 2011 to October 2015 from a single center in Korea. They were divided into 3 groups according to their baseline lipoprotein(a) levels: groups I (< 30 mg/dL, n = 1,388), II (30-49 mg/dL, n = 263), and III (≥50 mg/dL, n = 257). Three-point major adverse cardiovascular events (a composite of nonfatal myocardial infarction, nonfatal stroke, and cardiac death) at 3 years were compared among the 3 groups.

RESULTS

The patients were followed for 1094.0 (interquartile range, 1,033.8-1,095.0) days, during which a total of 326 (17.1%) three-point major adverse cardiovascular events occurred. Group III had higher rates of three-point major adverse cardiovascular events compared with Group I (23.0% vs. 15.7%; log-rank P = 0.009). In the subgroup analysis, group III had higher rates of three-point major adverse cardiovascular events compared with group I in patients with non-ST-segment elevation myocardial infarction (27.0% vs. 17.1%; log-rank P = 0.006), but not in patients with ST-segment elevation myocardial infarction (14.4% vs. 13.3%; log-rank P = 0.597). However, in multivariable Cox time-to-event models, baseline lipoprotein(a) levels were not associated with an increased incidence of three-point major adverse cardiovascular events, regardless of the type of acute myocardial infarction. Sensitivity analyses in diverse subgroups showed similar findings to those of the main analysis.

CONCLUSION

Baseline lipoprotein(a) levels in Korean patients with acute myocardial infarction were not independently associated with increased major adverse cardiovascular events at 3 years.

Secondary Cardiovascular Prevention after Acute Coronary Syndrome: Emerging Risk Factors and Novel Therapeutic Targets

The control of cardiovascular risk factors, the promotion of a healthy lifestyle, and antithrombotic therapy are the cornerstones of secondary prevention after acute coronary syndrome (ACS). However, many patients have recurrent ischemic events despite the optimal control of traditional modifiable risk factors and the use of tailored pharmacological therapy, including new-generation antiplatelet and lipid-lowering agents. This evidence emphasizes the importance of identifying novel risk factors and targets to optimize secondary preventive strategies. Lipoprotein(a) (Lp(a)) has emerged as an independent predictor of adverse events after ACS. New molecules such as anti-PCSK9 monoclonal antibodies, small interfering RNAs, and antisense oligonucleotides can reduce plasma Lp(a) levels and are associated with a long-term outcome benefit after the index event. The inflammatory stimulus and the inflammasome, pivotal elements in the development and progression of atherosclerosis, have been widely investigated in patients with coronary artery disease. More recently, randomized clinical trials including post-ACS patients treated with colchicine and monoclonal antibodies targeting cytokines yielded promising results in the reduction in major cardiovascular events after an ACS. Gut dysbiosis has also raised great interest for its potential pathophysiological role in cardiovascular disease. This evidence, albeit preliminary and needing confirmation by larger population-based studies, suggests the possibility of targeting the gut microbiome in particularly high-risk populations. The risk of recurrent ischemic events after ACS is related to the complex interaction between intrinsic predisposing factors and environmental triggers. The identification of novel risk factors and targets is fundamental to customizing patient clinical management with a precision medicine perspective.

Circulating lipoprotein (a) and all-cause and cause-specific mortality: a systematic review and dose-response meta-analysis

AIMS

To investigate the association between circulating lipoprotein(a) (Lp(a)) and risk of all-cause and cause-specific mortality in the general population and in patients with chronic diseases, and to elucidate the dose-response relations.

METHODS AND RESULTS

We searched literature to find prospective studies reporting adjusted risk estimates on the association of Lp(a) and mortality outcomes. Forty-three publications, reporting on 75 studies (957,253 participants), were included. The hazard ratios (HRs) and 95% confidence intervals (95%CI ) for the top versus bottom tertile of Lp(a) levels and risk of all-cause mortality were 1.09 (95%CI: 1.01-1.18, I²: 75.34%, n = 19) in the general population and 1.18 (95%CI: 1.04-1.34, I²: 52.5%, n = 12) in patients with cardiovascular diseases (CVD). The HRs for CVD mortality were 1.33 (95%CI: 1.11-1.58, I²: 82.8%, n = 31) in the general population, 1.25 (95%CI: 1.10-1.43, I²: 54.3%, n = 17) in patients with CVD and 2.53 (95%CI: 1.13-5.64, I²: 66%, n = 4) in patients with diabetes mellitus. Linear dose-response analyses revealed that each 50 mg/dL increase in Lp(a) levels was associated with 31% and 15% greater risk of CVD death in the general population and in patients with CVD. No non-linear dose-response association was observed between Lp(a) levels and risk of all-cause or CVD mortality in the general population or in patients with CVD (P_nonlinearity > 0.05).

CONCLUSION

This study provides further evidence that higher Lp(a) levels are associated with higher risk of all-cause mortality and CVD-death in the general population and in patients with CVD. These findings support the ESC/EAS Guidelines that recommend Lp(a) should be measured at least once in each adult person's lifetime, since our study suggests those with higher Lp(a) might also have higher risk of mortality.

Conventional Biomarkers for Predicting Clinical Outcomes in Patients with Heart Disease

Atherosclerosis is the main cause of cardiovascular disease worldwide. The progression of coronary atherosclerosis leads to coronary artery disease, with impaired blood flow to the myocardium and subsequent development of myocardial ischemia. Acute coronary syndromes and post-myocardial infarction heart failure are two of the most common complications of coronary artery disease and are associated with worse outcomes. In order to improve the management of patients with coronary artery disease and avoid major cardiovascular events, several risk assessment tools have been developed. Blood and imaging biomarkers, as well as clinical risk scores, are now available and validated for clinical practice, but research continues. The purpose of the current paper is to provide a review of recent findings regarding the use of humoral biomarkers for risk assessment in patients with heart disease.

Relationship between lipoprotein(a) and revascularization after percutaneous coronary intervention in type 2 diabetes mellitus patients with acute coronary syndrome

BACKGROUND

As a residual risk factor for coronary heart disease, lipoprotein(a) [Lp(a)] is associated with the occurrence of cardiovascular events after percutaneous coronary intervention (PCI). The revascularization rate after PCI is high among diabetic patients. However, the relationship between Lp(a) and revascularization after PCI in type 2 diabetes mellitus (T2DM) patients with acute coronary syndrome (ACS) remains unclear.

METHODS

The investigation was a single-center, observational, retrospective cohort study. Patients with T2DM who were first diagnosed with ACS and underwent PCI were included in the study. As a result, 362 patients were enrolled and divided into three groups according to tertiles on basis of Lp(a) levels (11.48 mg/dL and 21.70 mg/dL). The incidence of major adverse cardiac events (MACEs), including cardiac death, revascularization due to myocardial ischemia, readmission due to angina, and nonfatal stroke, was evaluated. Subgroups were established according to the low-density lipoprotein cholesterol (LDL-C) level (70 mg/dL).

RESULTS

During follow-up (median: 2.0 years), 69 MACEs occurred, and 76.81% of these patients underwent revascularization. The Lp(a) level in the MACE group was significantly higher than that in the non-MACE group (22.90 mg/dL vs. 14.10 mg/dL, p < .001). Kaplan-Meier analysis revealed that the incidence of adverse cardiovascular events was significantly higher in the high Lp(a) groups than in the low Lp(a) groups (p = .001), mainly because of the increased occurrence of revascularization irrespective of LDL-C level (<70 mg/dL; ≥70 mg/dL, both p < .05) rather than death, nonfatal stroke, or hospital readmission due to angina (both p > .05). The receiver operating characteristic (ROC) curve showed that the area under the curve (AUC) for Lp(a) in predicting the occurrence of MACE and revascularization were 0.664 and 0.668 respectively, both p < .05. Furthermore, multivariate Cox regression models indicated that Lp(a) was independently associated with revascularization [medium Lp(a) category: HR (95% CI): 2.988 (1.164-7.671), p = .023; high Lp(a) category: HR (95% CI): 4.937 (2.023-12.052), p < .001].

CONCLUSION

Lp(a) was an independent predictor of revascularization in patients with ACS complicated with T2DM, regardless of LDL-C levels. This suggests that Lp(a) measurement may help identify high-risk diabetic patients with ACS.

Lipoprotein a Combined with Fibrinogen as an Independent Predictor of Long-Term Prognosis in Patients with Acute Coronary Syndrome: A Multi-Center Retrospective Study

Background: Patients with acute coronary syndrome (ACS) still have a high risk of recurrence of major adverse cardiovascular and cerebrovascular events (MACCE). However, there are rare studies on the prediction of MACCE in patients with ACS using lipoprotein a [Lp(a)] combined with fibrinogen. The aim of this study was to analyze the predictive value of Lp(a) combined with fibrinogen for the long-term prognosis of patients with ACS. Methods: 804 patients with ACS admitted to 11 tertiary general hospitals in Chengdu from January 2017 to June 2019 were included in the study. According to the Lp(a) 300 mg/L, patients were assigned to the non-high Lp(a) group and high Lp(a) group. Patients were assigned to the non-high or high fibrinogen groups using the fibrinogen level of 3.08 g/L. Subsequently, patients were divided into group A, B, or C by Lp(a) combined with fibrinogen. The study endpoints were MACCE, including all-cause death, non-fatal myocardial infarction, non-fatal stroke, and revascularization. The incidences of MACCE among groups were compared. Lp(a), fibrinogen, Lp(a) combined with fibrinogen classifications were each added into the basic model to construct three new models. The C-index, net reclassification index (NRI) and integrated discrimination improvement (IDI) of the three new models were then compared. Results: The median follow-up was 16 months. During follow-up, the cumulative incidence of MACCE in group C was significantly higher than that measured in group A and B (p < 0.001). The results of the multivariate Cox regression analysis of MACCE showed that Lp(a) ≥300 mg/L with fibrinogen ≥3.08 g/L was an independent predictor of MACCE. According to the GRACE score and the statistical analyses, the basic model was constructed, which had a C-index of 0.694. The C-index, NRI, and IDI of the new model constructed using the basic model + Lp(a) combined with fibrinogen classification were 0.736, 0.095, and 0.094 respectively. Conclusions: Single Lp(a), single fibrinogen and Lp(a) combined with fibrinogen were independent predictors of MACCE in patients with ACS. The predictive value of Lp(a) combined with fibrinogen in patients with ACS was better than that of single Lp(a) and single fibrinogen.

Impact of Lipoprotein(a) concentrations on long-term cardiovascular outcomes in patients undergoing percutaneous coronary intervention: A large cohort study

BACKGROUND AND AIMS

Till now, the prognostic value of lipoprotein(a) [Lp(a)] in patients with coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI) remains controversial. We therefore conducted this study to evaluate the effect of Lp(a) levels on clinical outcomes in this population.

METHODS AND RESULTS

A total of 10,059 CAD patients who underwent PCI were prospectively enrolled in this cohort study, of which 6564 patients had Lp(a) ≤30 mg/dl and 3495 patients had Lp(a) > 30 mg/dl. The primary endpoint was major adverse cardiovascular and cerebrovascular event (MACCE), defined as a composite of all-cause death, myocardial infarction, stroke or unplanned revascularization. Multivariate Cox regression analysis and propensity-score matching analysis were performed. After propensity-score matching, 3449 pairs of patients were identified, and post-matching absolute standardized differences were <10% for all the covariates. At 2.4 years, the risk of MACCE was significantly higher in patients with elevated Lp(a) levels than those with normal Lp(a) levels in both overall population (13.0% vs. 11.4%; adjusted hazard ratio [HR] 1.142, 95% confidence interval [CI] 1.009-1.293; P = 0.040) and propensity-matched cohorts (13.0% vs. 11.2%; HR 1.167, 95%CI 1.019-1.337; P = 0.026). Of note, the predictive value of Lp(a) levels on MACCE tended to be more evident in individuals >65 years or those with left main and/or three-vessel disease. On the contrary, elevated Lp(a) levels had almost no effect on clinical outcomes in patients ≤65 years (P _interaction = 0.021) as well as those who had one- or two-vessel coronary artery disease (P _interaction = 0.086).

CONCLUSION

In CAD patients who underwent PCI, elevated Lp(a) levels were positively related to higher risk of MACCE at 2.4-year follow-up, especially in patients >65 years and those with left main and/or three-vessel disease.

REGISTRATION NUMBER

not applicable.

Lipoprotein(a) Modulates Carotid Atherosclerosis in Metabolic Syndrome

Background and Aim: High lipoprotein(a) [Lp(a)] is a well-established cardiovascular (CV) risk factor, but the effect of mildly elevated Lp(a) on CV health is largely unknown. Our aim was to evaluate if Lp(a) is associated with the severity of carotid atherosclerosis (CA) in the specific subset of metabolic syndrome (MetS).

Patients and Methods: Subjects with diagnosed MetS and ultrasound-assessed CA were enrolled. Those patients were categorized according to the severity of CA (moderate vs. severe), and the circulating levels of Lp(a) alongside with clinical, anthropometric, and biochemical data were collected.

Results: Sixty-five patients were finally included: twenty-five with moderate and forty with severe CA (all with asymptomatic disease). Intergroup comparison showed Lp(a) as the only significantly different variable [6 (2–12) mg/dl vs. 11.5 (6–29.5) mg/dl; p = 0.018]. Circulating levels of Lp(a) were also confirmed as the only variable independently associated with severity of CA at logistic regression analysis [OR 2.9 (95% CI 1.1–7.8); p = 0.040]. ROC curve analysis for Lp(a) confirmed a serum level of 10 mg/dl as the best cut-off value [AUC 0.675 (95% CI 0.548–0.786)]. Although sensitivity and specificity were suboptimal (69.0 and 70.4%, respectively)—likely due to the small sample size—this result is in line with those previously reported in the literature.

Conclusion: Lp(a) is independently associated with severity of CA in the subgroup of MetS patients.

The correlation between lipoprotein(a) elevations and the risk of recurrent cardiovascular events in CAD patients with different LDL-C levels

Background

Lipoprotein(a) [Lp(a)] elevation is an important risk factor for coronary artery disease (CAD). However, the correlation between Lp(a) elevations and the risk of recurrent cardiovascular events in patients with established cardiovascular disease is controversial. Some studies have shown that Low-density lipoprotein cholesterol (LDL-C) levels may influence the association between Lp(a) and cardiovascular risk. Our study aims to explore the correlation between Lp(a) elevations and cardiovascular risk in patients with different LDL-C levels.

Methods

We included 516 patients who received coronary stents due to acute coronary syndrome (ACS) and followed them for three years. They were divided into low-Lp(a) group and high-Lp(a) group according to Lp(a) levels, and the incidence of major adverse cardiovascular events (MACE) and acute coronary events (ACE) was compared between the two groups. Then the patients were divided into three subgroups (S1:LDL-C ≥ 1.8 mmol/L; S2:1.4 ≤ LDL-C < 1.8 mmol/L; S3:LDL-C < 1.4 mmol/L). The correlation between Lp(a) elevations and cardiovascular risk in different subgroups was analysed by Cox proportional hazards models.

Results

The incidence of MACE and ACE in the high-Lp(a) group was significantly higher than those in the low-Lp(a) group (P < 0.05). Lp(a) elevations had independent prognostic value from the statistical point of view (MACE: HR = 1.63, 95%CI = 1.12–2.38, P = 0.012; ACE: HR = 1.70, 95%CI = 1.03–2.81, P = 0.037). Subgroup analysis showed that Lp(a) elevations increased cardiovascular risk when LDL-C ≥ 1.4 mmol/L. However, this correlation no longer existed when LDL-C levels were very low (< 1.4 mmol/L) (MACE: HR = 0.49, 95%CI = 0.17–1.42, P = 0.186; ACE: HR = 0.68, 95%CI = 0.18–2.61, P = 0.570).

Conclusions

Lp(a) elevations are associated with recurrent cardiovascular events when LDL-C levels are high, but this association may change when LDL-C levels are extremely low. CAD patients with combination of LDL-C ≥ 1.4 mmol/L and Lp(a) elevations shall be considered as high-risk groups and require further medication for the reduction of their LDL-C levels.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02618-5.

Baseline Low-Density-Lipoprotein Cholesterol Modifies the Risk of All-Cause Death Associated With Elevated Lipoprotein(a) in Coronary Artery Disease Patients

Background: The prognostic value of elevated lipoprotein(a) [Lp(a)] in coronary artery disease (CAD) patients is inconsistent in previous studies, and whether such value changes at different low-density-lipoprotein cholesterol (LDL-C) levels is unclear. Methods and Findings: CAD patients treated with statin therapy from January 2007 to December 2018 in the Guangdong Provincial People's Hospital (NCT04407936) were consecutively enrolled. Individuals were categorized according to the baseline LDL-C at cut-off of 70 and 100 mg/dL. The primary outcome was 5-year all-cause death. Multivariate Cox proportional models and penalized spline analyses were used to evaluate the association between Lp(a) and all-cause mortality. Among 30,908 patients, the mean age was 63.1 ± 10.7 years, and 76.7% were men. A total of 2,383 (7.7%) patients died at 5-year follow-up. Compared with Lp(a) <50 mg/dL, Lp(a) ≥ 50 mg/dL predicted higher all-cause mortality (multivariable adjusted HR = 1.19, 95% CI 1.07-1.31) in the total cohort. However, when analyzed within each LDL-C category, there was no significant association between Lp(a) ≥ 50 mg/dL and higher all-cause mortality unless the baseline LDL-C was ≥ 100 mg/dL (HR = 1.19, 95% CI 1.04-1.36). The results from penalized spline analyses were robust. Conclusions: In statin-treated CAD patients, elevated Lp(a) was associated with increased risks of all-cause death, and such an association was modified by the baseline LDL-C levels. Patients with Lp(a) ≥ 50 mg/dL had higher long-term risks of all-cause death compared with those with Lp(a) <50 mg/dL only when their baseline LDL-C was ≥ 100 mg/dL.

Lipoprotein(a): a genetic marker for cardiovascular disease and target for emerging therapies

Lipoprotein(a) [Lp(a)] is an established cardiovascular risk factor, and growing evidence indicates its causal association with atherosclerotic disease because of the proatherogenic low-density lipoprotein (LDL)-like properties and the prothrombotic plasminogen-like activity of apolipoprotein(a) [apo(a)]. As genetics significantly influences its plasma concentration, Lp(a) is considered an inherited risk factor of atherosclerotic cardiovascular disease (ASCVD), especially in young individuals. Moreover, it has been suggested that elevated Lp(a) may significantly contribute to residual cardiovascular risk in patients with coronary artery disease and optimal LDL-C levels. Nonetheless, the fascinating hypothesis that lowering Lp(a) could reduce the risk of cardiovascular events - in primary or secondary prevention - still needs to be demonstrated by randomized clinical trials. To date, no specific Lp(a)-lowering agent has been approved for reducing the lipoprotein levels, and current lipid-lowering drugs have limited effects. In the future, emerging therapies targeting Lp(a) may offer the possibility to further investigate the relation between Lp(a) levels and cardiovascular outcomes in randomized controlled trials, ultimately leading to a new era in cardiovascular prevention. In this review, we aim to provide an updated overview of current evidence on Lp(a) as well as currently investigated therapeutic strategies that specifically address the reduction of the lipoprotein.

Gender difference in lipoprotein(a) concentration as a predictor of coronary revascularization in patients with known coronary artery disease

BACKGROUND AND AIMS

Whether there is a gender difference in the impact of elevated plasma Lp(a) levels on recurrent coronary events remains unclear. We, therefore, evaluated the association between Lp(a) levels and the occurrence of major adverse coronary events in a large series of coronary patients (32% women).

METHODS

This single-center prospective cohort study investigated 3034 consecutive patients admitted to the Coronary Care Unit with a diagnosis of coronary ischemia. According to the inclusion criteria, 2374 patients completed the follow-up (mean of 2 years). The end-points were non-fatal myocardial infarction (MI), revascularization and coronary deaths.

RESULTS

Elevated Lp(a) levels were significantly associated with rate of revascularization, but not with non-fatal MI and cardiac death. According to Lp(a) stratification (≤30 mg/dl, >30-50 mg/dl and ≥50 mg/dl), there was a significant rise of revascularization events in the whole sample of participants, with a trend in hazard ratio (HR) of 1.23 (95% CI 1.04-1.46) and a 6% rise for every 10 mg/dl increment in Lp(a) levels. This effect was mainly driven by women (HR 2.04, 95%CI 1.33-3.12) who showed a 14% incremental risk for every 10 mg/dl rise in Lp(a) levels.

CONCLUSIONS

In patients with coronary artery disease, elevated plasma Lp(a) levels were found to be a potentially useful predictor of the need for coronary revascularizations, especially in women.

Increased cardiovascular risk associated with hyperlipoproteinemia (a) and the challenges of current and future therapeutic possibilities

Population, genetic, and clinical studies demonstrated a causative and continuous, from other plasma lipoproteins independent relationship between elevated plasma lipoprotein (a) [Lp(a)] concentration and the development of cardiovascular disease (CVD), mainly those related to athe-rosclerotic CVD, and calcific aortic stenosis. Currently, a strong international consensus is still lacking regarding the single value which would be commonly used to define hyperlipoproteinemia (a). Its prevalence in the general population is estimated to be in the range of 10%–35% in accordance with the most commonly used threshold levels (>30 or >50 mg/dL). Since elevated Lp(a) can be of special importance in patients with some genetic disorders, as well as in individuals with otherwise controlled major risk factors, the identification and establishment of the proper therapeutic interventions that would lower Lp(a) levels and lead to CVD risk reduction could be very important. The majority of the classical lipid-lowering agents (statins, ezetimibe, and fibrates), as well as nutraceuticals (CoQ10 and garlic), appear to have no significant effect on its plasma levels, whereas for the drugs with the demonstrated Lp(a)-lowering effects (aspirin, niacin, and estrogens), their clinical efficacy in reducing cardiovascular (CV) events has not been unequivocally proven yet. Both Lp(a) apheresis and proprotein convertase subtilisin/kexin type 9 inhibitors can reduce the plasma Lp(a) by approximately 20%–30% on average, in parallel with much larger reduction of low-density lipoprotein cholesterol (up to 70%), what puts us in a difficulty to conclude about the true contribution of lowered Lp(a) to the reduction of CV events. The most recent advancement in the field is the introduction of the novel apolipoprotein (a) [apo(a)] antisense oligonucleotide therapy targeting apo(a), which has already proven itself as being very effective in decreasing plasma Lp(a) (by even >90%), but should be further tested in clinical trials. The aim of this review was to present some of the most important accessible scientific data, as well as dilemmas related to the currently and potentially in the near future more widely available therapeutic options for the management of hyperlipoproteinemia (a).

Lipoprotein (a) predicts recurrent worse outcomes in type 2 diabetes mellitus patients with prior cardiovascular events: a prospective, observational cohort study

BACKGROUND

Merging studies have reported the association of lipoprotein(a) [Lp(a)] with poor outcomes of coronary artery disease (CAD) in patients with type 2 diabetes mellitus (T2DM). However, the prognostic importance of Lp(a) for recurrent cardiovascular events (CVEs) is currently undetermined in patients with T2DM and prior CVEs.

METHODS

From April 2011 to March 2017, we consecutively recruited 2284 T2DM patients with prior CVEs. Patients were categorized into low, medium, and high groups by Lp(a) levels and followed up for recurrent CVEs, including nonfatal acute myocardial infarction, stroke, and cardiovascular mortality. Kaplan-Meier, Cox regression and C-statistic analyses were performed.

RESULTS

During 7613 patient-years' follow-up, 153 recurrent CVEs occurred. Lp(a) levels were significantly higher in patients with recurrent CVEs than counterparts (20.44 vs. 14.71 mg/dL, p = 0.002). Kaplan-Meier analysis revealed that the event-free survival rate was dramatically lower in high and medium Lp(a) groups than that in low group irrespective of HBA1c status (< 7.0%; ≥ 7.0%, both p < 0.05). Furthermore, multivariate Cox regression models indicated that Lp(a) was independently associated with high risk of recurrent CVEs [HR(95% CI): 2.049 (1.308-3.212)], such data remains in different HBA1c status (HR(95% CI): < 7.0%, 2.009 (1.051-3.840); ≥ 7.0%, 2.162 (1.148-4.073)). Moreover, the results of C-statistic were significantly improved by 0.029 when added Lp(a) to the Cox model.

CONCLUSIONS

Our data, for the first time, confirmed that Lp(a) was an independent predictor for recurrent CVEs in T2DM patients with prior CVEs, suggesting that Lp(a) measurement may help to further risk stratification for T2DM patients after they suffered a first CVE.