Atherogenic index of plasma and coronary artery calcification progression beyond traditional risk factors according to baseline coronary artery calcium score

Elevated atherogenic index of plasma increased the risk of myocardial infarction in a general population

PURPOSE

The atherogenic index of plasma (AIP) has been shown to be related to cardiovascular disease risk, but evidence on the longitudinal pattern of AIP during follow-up is limited. We aimed to explore the associations of baseline and long-term AIP with the risk of myocardial infarction (MI).

METHODS

We included 98,861 participants in the Kailuan Study who were free of MI at baseline. AIP was calculated as log (triglyceride/high-density lipoprotein cholesterol). Long-term AIP included the long-term mean AIP (mean AIP from baseline to the first occurrence of MI or the end of follow-up) and number of visits with high AIP (above the cutoff value at the first three visits). The baseline and updated mean AIP were in operationalized as quartiles. Cox proportional hazard models were used to determine the associations between AIP and risk of MI. We excluding all deaths during the follow-up visits in the sensitivity analysis.

RESULTS

During a median follow-up of 12.80 years, 1804 participants developed MI. Compared with quartile 1, the adjusted hazard ratios in baseline and updated mean AIP quartile 4 were 1.63 (95% CI, 1.41-1.88) and 1.59 (95% CI, 1.37-1.83), respectively. Compared with participants who did not have a high AIP, the HR among individuals with AIP elevated by three times was 1.94 (95% CI,1.55-2.45). The sensitivity analysis showed similar associations.

CONCLUSIONS

Elevated levels of both baseline and long-term AIP increased the risk of MI.

The relation between atherogenic index of plasma and cardiovascular outcomes in prediabetic individuals with unstable angina pectoris

BACKGROUND

The atherogenic index of plasma (AIP) is a novel biomarker associated with atherosclerosis, and an important risk factor for atherosclerosis, but its relation with cardiovascular prognosis in prediabetic patients with unstable angina pectoris (UAP) is still uncertain.

METHODS

This study included 1096 prediabetic patients with UAP who were subjected to follow-up for a maximum of 30 months, with cardiac death, refractory angina, and non-fatal myocardial infarction (MI) being the primary cardiovascular endpoints.

RESULTS

A significantly increased AIP was observed for the group with primary cardiovascular endpoints. Kaplan-Meier curves corresponding to these endpoints revealed pronounced differences between these two AIP groups (Log-rank P < 0.001). Multivariate Cox proportional hazards analyses highlighted AIP as being independent related to this primary endpoint (HR 1.308, 95% CI: 1.213-1.412, P < 0.001). AIP addition to the baseline risk model improved the prediction of the primary endpoint (AUC: baseline model, 0.622, vs. baseline model + AIP, 0.739, P < 0.001).

CONCLUSIONS

AIP could be used to predict cardiovascular events in prediabetic individuals with UAP.

The Comparison of the Associations of Lipoprotein(a) and the Atherogenic Index of Plasma With Coronary Artery Calcification in Patients Without High LDL-C: A Comparative Analysis

Objective

Lipoprotein(a) (Lp[a]) and the atherogenic index of plasma (AIP) have been reported as predictive markers of coronary artery calcium (CAC). However, previous studies demonstrated that the cardiovascular risk associations with Lp(a) are attenuated in patients with low-density lipoprotein cholesterol (LDL-C) levels ≤135 mg/dL. However, few articles have identified the risk factors of CAC in patients without high LDL-C. Therefore, we performed this study to investigate the association of Lp(a) and AIP with CAC in patients with LDL-C levels ≤135 mg/dL.

Methods

This study included 625 lipid-lowering agent naive patients with LDL-C levels ≤135 mg/dL who underwent coronary computed tomographic angiography. We performed multivariate logistic regression analysis to evaluate the risk factors for a coronary artery calcium score (CACS) >0, CACS ≥400, and CAC ≥90th percentile.

Results

The mean age of the patients was 55.0±7.9 years and their mean LDL-C level was 94.7 ±23.3 mg/dL. Multivariate regression analysis showed that age, male sex, diabetes, hypertension, Lp(a), and AIP were independent predictors of CAS>0. Age, male sex, and diabetes were independent predictors of CACS≥400. Diabetes, hypertension, and AIP were independent predictors of CAC ≥90th percentile (all p<0.05). Unlike Lp(a), higher AIP tertiles were associated with significantly higher CAC percentiles and greater proportions of patients with CACS ≥400 and CAC ≥90th percentile.

Conclusion

In patients without high LDL-C, AIP could be a more reliable predictor of CAC than Lp(a).

Atherosclerosis Calcification: Focus on Lipoproteins

Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipids in the vessel wall, leading to the formation of an atheroma and eventually to the development of vascular calcification (VC). Lipoproteins play a central role in the development of atherosclerosis and VC. Both low- and very low-density lipoproteins (LDL and VLDL) and lipoprotein (a) (Lp(a)) stimulate, while high-density lipoproteins (HDL) reduce VC. Apolipoproteins, the protein component of lipoproteins, influence the development of VC in multiple ways. Apolipoprotein AI (apoAI), the main protein component of HDL, has anti-calcific properties, while apoB and apoCIII, the main protein components of LDL and VLDL, respectively, promote VC. The role of lipoproteins in VC is also related to their metabolism and modifications. Oxidized LDL (OxLDL) are more pro-calcific than native LDL. Oxidation also converts HDL from anti- to pro-calcific. Additionally, enzymes such as autotaxin (ATX) and proprotein convertase subtilisin/kexin type 9 (PCSK9), involved in lipoprotein metabolism, have a stimulatory role in VC. In summary, a better understanding of the mechanisms by which lipoproteins and apolipoproteins contribute to VC will be crucial in the development of effective preventive and therapeutic strategies for VC and its associated cardiovascular disease.

Predictive Value of Resting Fractional Flow Reserve and Atherogenic Index of Plasma for Evaluation of Physiologically Significant Coronary Artery Lesions

This study aimed to assess the relationship between the atherogenic index of plasma (AIP) and resting distal-to-aortic pressure ratio (Pd/Pa) in patients with intermediate coronary artery stenosis. This retrospective study included 802 chronic coronary syndrome patients with intermediate coronary artery stenosis who underwent fractional flow reserve (FFR) measurement. The resting Pd/Pa showed a significant negative correlation with AIP (rho= -.205, p < .001). When final FFR was divided into three tertiles (≤80, 81-89, ≥90), resting Pd/Pa was significantly lower, and AIP was markedly higher in the lower final FFR tertiles (both AIP and resting Pd/Pa differed significantly across the all three tertiles, p < .001). Furthermore, functionally significant stenosis independent predictors in multivariate analyses were AIP and resting Pd/Pa (p = .010 and p < .001, respectively). We observed for the first time an increase in AIP levels in the presence of functionally significant stenoses that may help better planning and identification of those patients with the functionally substantial atherosclerotic burden.

Sex difference in the relationship of the Atherogenic index of plasma with coronary artery lesions in diabetes: a cross-sectional study

BACKGROUND

Coronary artery disease (CAD) tends to progress more rapidly in the type 2 diabetes mellitus (T2DM) population and may be associated with dyslipidemia. This study explored the relationship of the atherogenic index of plasma (AIP) to coronary artery lesions in the T2DM population of different sexes.

METHODS

The research included 737 individuals who underwent coronary angiography from 2018 to 2019. The included clinical data and coronary angiographic findings were analyzed in the study.

RESULTS

Among the included male patients, those with coronary artery disease had a higher adjusted AIP (aAIP). In correlation analysis, the Gensini score was positively and linearly correlated with the aAIP in male T2DM patients. An aAIP cutoff value of 1.17 was determined from the receiver operating characteristic (ROC) curve of aAIP versus CAD risk in the study population. After dividing the aAIP into two groups by the cutoff value of aAIP, the group with the lower value was used as the control for logistic regression analysis. The results showed that the risk of CAD and multivessel lesions was higher when the aAIP was higher in men with T2DM, and this positive association was not affected by HbA1c, age, or the presence of glucose-lowering therapy. The ROC curve suggested that the aAIP can predict CAD risk in male T2DM patients. However, no relationship was found in the included female patients.

CONCLUSION

In male T2DM patients, AIP may serve as a reliable marker for coronary artery lesions.

Glycemic control is independently associated with rapid progression of coronary atherosclerosis in the absence of a baseline coronary plaque burden: a retrospective case-control study from the PARADIGM registry

BACKGROUND

The baseline coronary plaque burden is the most important factor for rapid plaque progression (RPP) in the coronary artery. However, data on the independent predictors of RPP in the absence of a baseline coronary plaque burden are limited. Thus, this study aimed to investigate the predictors for RPP in patients without coronary plaques on baseline coronary computed tomography angiography (CCTA) images.

METHODS

A total of 402 patients (mean age: 57.6 ± 10.0 years, 49.3% men) without coronary plaques at baseline who underwent serial coronary CCTA were identified from the Progression of Atherosclerotic Plaque Determined by Computed Tomographic Angiography Imaging (PARADIGM) registry and included in this retrospective study. RPP was defined as an annual change of ≥ 1.0%/year in the percentage atheroma volume (PAV).

RESULTS

During a median inter-scan period of 3.6 years (interquartile range: 2.7-5.0 years), newly developed coronary plaques and RPP were observed in 35.6% and 4.2% of the patients, respectively. The baseline traditional risk factors, i.e., advanced age (≥ 60 years), male sex, hypertension, diabetes mellitus, hyperlipidemia, obesity, and current smoking status, were not significantly associated with the risk of RPP. Multivariate linear regression analysis showed that the serum hemoglobin A1c level (per 1% increase) measured at follow-up CCTA was independently associated with the annual change in the PAV (β: 0.098, 95% confidence interval [CI]: 0.048-0.149; P < 0.001). The multiple logistic regression models showed that the serum hemoglobin A1c level had an independent and positive association with the risk of RPP. The optimal predictive cut-off value of the hemoglobin A1c level for RPP was 7.05% (sensitivity: 80.0%, specificity: 86.7%; area under curve: 0.816 [95% CI: 0.574-0.999]; P = 0.017).

CONCLUSION

In this retrospective case-control study, the glycemic control status was strongly associated with the risk of RPP in patients without a baseline coronary plaque burden. This suggests that regular monitoring of the glycemic control status might be helpful for preventing the rapid progression of coronary atherosclerosis irrespective of the baseline risk factors. Further randomized investigations are necessary to confirm the results of our study.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02803411.

The atherogenic index of plasma: A novel factor more closely related to non-alcoholic fatty liver disease than other lipid parameters in adults

Background and aims

The relationship of non-alcoholic fatty liver disease (NAFLD) with the atherogenic index of plasma (AIP) is unclear. This study aims to detect the association between AIP and NAFLD, compare the discriminative power of AIP with other lipid parameters for NAFLD, and establish a discriminant model using physical examination data.

Methods

Participants aged over 20 years who underwent routine physical examination in Beijing Chaoyang Hospital from April 2016 to August 2020 were included. We categorized subjects based on hepatic ultrasound results and analyzed the association between NAFLD risk and AIP, conventional plasma lipids, remnant cholesterol (RC), triglyceride and glucose (TyG) index, and other atherogenic indices (n = 112,200) using logistic regression, restricted cubic spline regression, and receiver operating characteristic curve.

Results

Out of the 112,200 subjects, 30.4% had NAFLD. The body weight index, plasma glucose, conventional lipids, TyG index, AIP, atherogenic coefficient (AC), and coronary risk index (CRI) were significantly higher, while HDL-C was lower (p < 0.001) in patients with NAFLD than those without NAFLD (all p < 0.001). Compared with conventional lipids, RC, TyG index, AC, and CRI, AIP had a stronger correlation with the risk of NAFLD (OR 6.71, 95% CI 6.23–7.22, p < 0.001) after adjusting confounders and presented a non-linear dose–response relationship (p < 0.0001). The optimal cut-off value of AIP was 0.05 and the area under the curve (AUC) was 0.82 (95% CI: 0.81–0.82) with high sensitivity and specificity. The AUC of the simplified three-variable NAFLD discriminant model was 0.90 in both the training set and the validation set.

Conclusion

AIP was significantly associated with NAFLD and showed superior discriminative performance to other lipid parameters. These findings might help screen NAFLD in high-risk individuals and reduce the prevalence of NAFLD.

Atherogenic index of plasma as an additional marker of adverse cardiovascular outcomes

Aim. Using a representative sample of the Krasnoyarsk Krai population, to evaluate the distribution of the atherogenic index of plasma (AIP), logarithmically transformed ratio of molar concentrations of triglycerides to high-density lipoprotein-cholesterol, and to identify  possible associations between AIP, various cardiovascular diseases, and metabolic parameters.

Material and methods. The study included a random representative sample of 1603 residents of the Krasnoyarsk and Berezovsky rural district aged 25-64 years as part of the Epidemiology of Cardiovascular Diseases and their Risk Factors in Regions of Russian Federation (ESSE-RF) study. Statistical processing was performed using IBM SPSS v22 and Microsoft Excel 2021 programs. We assessed the prevalence of hypertension (HTN), coronary artery disease, myocardial infarction (MI), stroke and renal dysfunction in the whole sample and in groups with different risk depending on AIP. Differences between groups were tested by Yates’s chi-squared test and were considered significant at p≤0,05.

Results. Depending on AIP value, 73,5% of participants were in the low-risk group (AIP <0,10), 10,4% — in moderate risk group (AIP, 0,100,24) and 16,1% — in high-risk group (AIP>0,24). The prevalence of prior MI or stroke in the moderate and high-risk group for AIP was significantly higher than in the low-risk group (p=0,024). A regular increase in HTN prevalence was registered from 42,6% in the lowrisk group to 71,4% in the high-risk group for AIP (p<0,001 for all). There was a significant increase in the proportion of patients with a combination of HTN + elevated low-density lipoprotein cholesterol levels as AIP risk increased — from 28,4% at low risk to 45,2% at high risk. There were no significant differences between AIP risk groups in the prevalence of coronary artery disease and renal dysfunction.

Conclusion. AIP is a simple additional estimated parameter that characterizes the atherogenic properties of plasma. Based on a cohort of Krasnoyarsk Krai subjects, an elevated level of AIP is associated with an increased prevalence of MI and strokes. Determination of AIP may be especially useful in the case of normal baseline low-density lipoprotein cholesterol levels.

Atherogenic index of plasma is associated with major adverse cardiovascular events in patients with type 2 diabetes mellitus

Background

Previous studies reported the prognostic value of the atherogenic index of plasma (AIP) in the course of atherosclerosis and other cardiovascular diseases (CVDs). Still, the predictive utility of the AIP is unknown among patients with type 2 diabetes mellitus (T2DM).

Methods

This was a secondary analysis of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study, which randomized 10,251 patients with long-lasting T2DM. ROC curve analysis was used to determine an optimal threshold for AIP, and the study population was divided into high and low AIP groups. Univariable and multivariable Cox proportional hazards regression analyses were used to determine the association between AIP and primary (major adverse cardiovascular events [MACEs], including nonfatal myocardial infarction, nonfatal stroke, and/or death from cardiovascular causes) and secondary outcomes (all-cause mortality). Stratified analyses were performed to control for the confounding factors.

Results

AIP was an independent risk factor for the prognosis of T2DM (HR = 1.309; 95% CI 1.084–1.581; P = 0.005). The threshold for AIP was determined to be 0.34 in the study population. After adjustments for confounding factors, multivariable analysis showed that AIP was associated with the risk of MACEs (Model 1: HR = 1.333, 95% CI 1.205–1.474, P < 0.001; Model 2: HR = 1.171, 95% CI 1.030–1.333, P = 0.016; Model 3: HR = 1.194, 95% CI 1.049–1.360, P = 0.007), all-cause mortality (Model 1: HR = 1.184, 95% CI 1.077–1.303, P < 0.001), cardiovascular death (Model 1: HR = 1.422, 95% CI 1.201–1.683, P < 0.001; Model 3: HR = 1.264, 95% CI 1.015–1.573, P = 0.036), and nonfatal myocardial infarction (Model 1: HR = 1.447, 95% CI 1.255–1.669, P < 0.001; Model 2: HR = 1.252, 95% CI 1.045–1.499, P = 0.015; Model 3: HR = 1.284, 95% CI 1.071–1.539, P = 0.007). Subgroup stratified analyses showed that AIP might interact with sex, a classical risk factor of cardiovascular events.

Conclusions

This study showed that AIP might be a strong biomarker that could be used to predict the risk of cardiovascular events in patients with T2DM.

Trial registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000620.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01393-5.

Atherogenic Index of Plasma and the Risk of In-Stent Restenosis in Patients with Acute Coronary Syndrome beyond the Traditional Risk Factors

Aim: Recently, the atherogenic index of plasma (AIP) has been proposed as a novel, reliable plasma atherogenicity marker. This study aimed to investigate the association of AIP with the risk of in-stent restenosis (ISR) in patients with acute coronary syndrome (ACS).

Methods: This study retrospectively enrolled patients with ACS followed by angiography within 6 to 18 months after successful percutaneous coronary intervention (PCI) with a drug-eluting stent (DES). And the participants were divided into ISR or non-ISR groups based on the angiographic follow-up results. AIP was defined as the base 10 logarithm of the ratio of serum triglyceride (mmol/L) to high-density lipoprotein cholesterol (mmol/L).

Results: This study recruited 1319 patients with ACS, 199 of which had ISR. Compared with the non-ISR group, patients in the ISR group had higher level of AIP (0.199±0.290 vs 0.131±0.282,p=0.002). In the multiple logistic regression analysis, AIP was an independent risk factor for DES-ISR (OR=2.100, 95% CI 1.134 to 3.891,p=0.018). When we modulated AIP as a categorical variable, the risk of DES-ISR increased in quartile 4 compared to quartile 1 (OR=1.713, 95% CI 1.040 to 2.822,p=0.034). Furthermore, this association remains stable in various subgroups. Unexpectedly, the subgroup analysis suggested AIP and DES-ISR had a stronger positive association in individuals with low-density lipoprotein cholesterol (LDL-C) ＜1.8 mmol/L.

Conclusions: AIP and the risk of DES-ISR were positively and independently correlated in patients with ACS, especially in those with an LDL-C ＜1.8 mmol/L.