Comparisons of Risk Factors for Abdominal Aortic Aneurysm and Coronary Heart Disease: A Prospective Cohort Study

Differences in risk factor profiles for peripheral artery disease compared to coronary, cerebral and carotid artery

The aim of this study was to evaluate the greatest drivers for development of lower extremity peripheral artery disease (PAD) in relation to coronary, precerebral, or cerebral artery disease This prospective study (Malmö Diet and Cancer study) included 26,681 participants. The diagnosis of incident PAD, coronary artery disease (CoAD), atherothrombotic ischemic stroke (IS) free from atrial fibrillation or flutter, and carotid artery disease (CaAD) was validated. A modified Lunn-McNeil competing risk analysis was performed to compare the Hazard Ratio (HR) strength of PAD in relation to CoAD, IS, or CaAD. The estimated population attributable risk fractions (PAF) for each atherosclerotic manifestation were estimated by first fit an age and sex adjusted Cox proportional hazard regression, and then estimate the PAF using the Direct method. Male sex, age, and hypertension were risk factors for development of all atherosclerotic manifestations. Current smoking accounted for 45.6% (95% CI 41.1-47.2), 16.1%, 14.0%, and 23.3% of the risk for development of PAD, CoAD, IS, and CaAD, respectively. Hypertension was more associated with development of PAD than CoAD (p = 0.009). Smoking and diabetes mellitus were positively associated with all four manifestations, but these associations were significantly stronger for PAD than the other three manifestations. Smoking and diabetes mellitus had a larger impact on incident PAD than incident coronary, cerebral or precerebral artery manifestations. Since the lower extremity arteries are the easiest to access and examine, they may be considered as the first arterial bed to examine in patients at increased risk for atherosclerotic manifestations.

Olfactory Receptors and Aortic Aneurysm: Review of Disease Pathways

Aortic aneurysm, the pathological dilatation of the aorta at distinct locations, can be attributed to many different genetic and environmental factors. The resulting pathobiological disturbances generate a complex interplay of processes affecting cells and extracellular molecules of the tunica interna, media and externa. In short, aortic aneurysm can affect processes involving the extracellular matrix, lipid trafficking/atherosclerosis, vascular smooth muscle cells, inflammation, platelets and intraluminal thrombus formation, as well as various endothelial functions. Many of these processes are interconnected, potentiating one another. Newer discoveries, including the involvement of odorant olfactory receptors in these processes, have further shed light on disease initiation and pathology. Olfactory receptors are a varied group of G protein coupled-receptors responsible for the recognition of chemosensory information. Although they comprise many different subgroups, some of which are not well-characterized or identified in humans, odorant olfactory receptors, in particular, are most commonly associated with recognition of olfactory information. They can also be ectopically localized and thus carry out additional functions relevant to the tissue in which they are identified. It is thus the purpose of this narrative review to summarize and present pathobiological processes relevant to the initiation and propagation of aortic aneurysm, while also incorporating evidence associating these ectopically functioning odorant olfactory receptors with the overall pathology.

Plasma proteomics analysis reveals potential biomarkers for intracranial aneurysm formation and rupture

The aim of this study was to investigate the plasma proteome in individuals with intracranial aneurysms (IAs) and identify biomarkers associated with the formation and rupture of IAs. Proteomic profiles (N = 1069 proteins) were assayed in plasma (N = 120) collected from patients with ruptured and unruptured intracranial aneurysms (RIA and UIA), traumatic subarachnoid hemorrhage (tSAH), and healthy controls (HC) using tandem mass tag (TMT) labeling quantitative proteomics analysis. Gene ontology (GO) and pathway analysis revealed that these relevant proteins were involved in immune response and extracellular matrix organization pathways. Seven candidate biomarkers were verified by ELISA in a completely separate cohort for validation (N = 90). Among them, FN1, PON1, and SERPINA1 can be utilized as diagnosis biomarkers of IA, with a combined area under the ROC curve of 0.891. The sensitivity was 93.33%, specificity was 75.86%, and accuracy was 87.64%. PFN1, ApoA-1, and SERPINA1 can serve as independent risk factors for predicting aneurysm rupture. The combined prediction of aneurysm rupture yielded an area under the ROC curve of 0.954 with a sensitivity of 96.15%, specificity of 81.48%, and accuracy of 88.68%. This prediction model was more effective than PHASES score. In conclusion, high-throughput proteomics analysis with population validation was performed to assess blood-based protein expression characteristics. This revealed the potential mechanism of IA formation and rupture, facilitating the discovery of biomarkers. SIGNIFICANCE: Although the annual rupture rate of small unruptured aneurysms is believed to be minimal, studies have indicated that ruptured aneurysms typically have an average size of 6.28 mm, with 71.8% of them being <7 mm in diameter. Hence, evaluating the possibility of rupture in UIA and making a choice between aggressive treatment and conservative observation emerges as a significant challenge in the management of UIA. No biomarker or scoring system has been able to satisfactorily address this issue to date. It would be significant to develop biomarkers that could be used for early diagnosis of IA as well as for prediction of IA rupture. After TMT proteomics analysis and ELISA validation in independent populations, we found that FN1, PON1, and SERPINA1 can be utilized as diagnostic biomarkers for IA, and PFN1, ApoA-1, and SERPINA1 can serve as independent risk factors for predicting aneurysm rupture. Especially, when combined with ApoA-1, SERPINA1, and PFN1 for predicting IA rupture, the area under the curve (AUC) was 0.954 with a sensitivity of 96.15%, specificity of 81.48%, and accuracy of 88.68%. This prediction model was more effective than PHASES score.

Abdominal aortic aneurysm and cardiometabolic traits share strong genetic susceptibility to lipid metabolism and inflammation

Abdominal aortic aneurysm has a high heritability and often co-occurs with other cardiometabolic disorders, suggesting shared genetic susceptibility. We investigate this commonality leveraging recent GWAS studies of abdominal aortic aneurysm and 32 cardiometabolic traits. We find significant genetic correlations between abdominal aortic aneurysm and 21 of the cardiometabolic traits investigated, including causal relationships with coronary artery disease, hypertension, lipid traits, and blood pressure. For each trait pair, we identify shared causal variants, genes, and pathways, revealing that cholesterol metabolism and inflammation are shared most prominently. Additionally, we show the tissue and cell type specificity in the shared signals, with strong enrichment across traits in the liver, arteries, adipose tissues, macrophages, adipocytes, and fibroblasts. Finally, we leverage drug-gene databases to identify several lipid-lowering drugs and antioxidants with high potential to treat abdominal aortic aneurysm with comorbidities. Our study provides insight into the shared genetic mechanism between abdominal aortic aneurysm and cardiometabolic traits, and identifies potential targets for pharmacological intervention.

Five Year Post-Endovascular Aneurysm Repair Aneurysm Sac Evolution in the GREAT Registry: an Insight in Diabetics Using Propensity Matched Controls

OBJECTIVE

To assess differences in the five year abdominal aortic aneurysm (AAA) sac regression rate after endovascular aneurysm repair (EVAR) in patients with and without diabetes mellitus (DM).

METHODS

An international prospective registry (Europe, USA, Brazil, Australia, and New Zealand) of patients treated with the GORE EXCLUDER endograft. All scheduled EVARs for infrarenal AAA between 2014 and 2016 with complete five year imaging follow up were included. Emergency procedures, ancillary proximal procedures, and inflammatory and infectious aetiologies were excluded. Descriptive and inferential statistics, and Cox proportional hazards survival models were used. A control group of patients without DM with similar age and comorbidities was selected using propensity scores, matched in a 1:2 scheme.

RESULTS

A total of 2 888 patients (86.1% male; mean age 73.5 ± 8 years) was included, of whom 545 (18.9%) had DM. Patients with DM had higher rates of hypertension (89.2% vs. 78.4%), dyslipidaemia (76.0% vs. 60.7%), coronary artery disease (52.3% vs. 37.9%), and chronic renal impairment (20.9% vs. 14.0%) (all p < .001). The mean pre-procedural AAA diameter was 58.1 ± 10 mm. Five years post-EVAR, the type 1A endoleak rate was 1.1% (0.6% DM vs. 1.2% non-DM), the endograft related re-intervention rate was 7.3% (6.2% vs. 7.6%), the major adverse cardiovascular event (MACE) rate was 1.4% (1.1% vs. 1.5%), and aortic related mortality rate was 1.0% (0.6% vs. 1.2%), without statistically significant differences between groups. The overall five year mortality rate was higher in diabetics (36.3% vs. 30.5%; hazard ratio [HR] 1.30, 95% confidence interval [CI] 1.07 - 1.58; p = .001). No statistically significant differences were found in sac regression rate (≥ 5 mm) between diabetics and non-diabetics 70.0% vs. 73.1%; HR 0.88, 95% CI 0.75-1.04; p = .131. These differences remained statistically non-significant after excluding patients performed out of instructions for use (p = .61) and patients with types 1, 2 or 3 endoleaks (p = .39).

CONCLUSION

The paradoxical relationship between DM and AAA does not appear to result in differences in post-EVAR sac regression rates. However, even when controlling for other comorbidities, patients with DM undergoing EVAR may have a higher five year mortality rate.

Diabetes and Abdominal Aortic Aneurysm: Is the Protective Effect on AAA Due to Antidiabetic Medications Alone, Due to the Disease Alone, or Both?

Diabetes is a metabolic disease that may result in multiple microvascular and macrovascular diseases. Interestingly, many studies have demonstrated the inverse relationship between diabetes and the development and expansion of abdominal aortic aneurysm (AAA). One hypothesis is that the aortic wall stiffness resulting from hyperglycemia and advanced glycation end products could delay the development and growth of AAA. Other studies have proposed that the concurrent use of antidiabetic medications which promote anti-inflammatory cytokines while hindering pro-inflammatory cytokines may potentially be the reason for this protective effect of diabetes on AAA. Contrastingly, the presence of diabetes has been found to have a negative effect on the outcome of AAA following its repair which may be due to elevated blood glucose negatively affecting the healing process. The current literature has also demonstrated the negative impact of the use of fluoroquinolones on AAA. This comprehensive review critically reviewed and summarized the role of diabetes, anti-diabetes medications and fluoroquinolones on AAA, and on the effect of diabetes and certain anti-diabetes medications on outcomes following its repair.

Revisiting an old relationship: the causal associations of the ApoB/ApoA1 ratio with cardiometabolic diseases and relative risk factors-a mendelian randomization analysis

BACKGROUND

It has been confirmed that the ApoB/ApoA1 ratio is closely associated with the incidence of cardiometabolic diseases (CMD). However, due to uncontrolled confounding factors in observational studies, the causal relationship of this association remains unclear.

METHODS

In this study, we extracted the ApoB/ApoA1 ratio and data on CMD and its associated risk factors from the largest European Genome-Wide Association Study. The purpose was to conduct Mendelian Randomization (MR) analysis. The causal relationship between the ApoB/ApoA1 ratio and CMD was evaluated using both univariable and multivariable MR analyses. Furthermore, bidirectional MR analysis was performed to estimate the causal relationship between the ApoB/ApoA1 ratio and risk factors for CMD. The final verification confirmed whether the ApoB/ApoA1 ratio exhibits a mediating effect in CMD and related risk factors.

RESULTS

In terms of CMD, a noteworthy correlation was observed between the increase in the ApoB/ApoA1 ratio and various CMD, including ischemic heart disease, major adverse cardiovascular events, aortic aneurysm, cerebral ischemic disease and so on (all PFDR<0.05). Meanwhile, the ApoB/ApoA1 ratio was significantly associated with CMD risk factors, such as hemoglobin A1c, fasting insulin levels, waist-to-hip ratio, sedentary behavior, and various others, demonstrating a notable causal relationship (all PFDR<0.05). Additionally, the ApoB/ApoA1 ratio played a mediating role in CMD and relative risk factors.

CONCLUSIONS

This MR study provides evidence supporting the significant causal relationship between the ApoB/ApoA1 ratio and CMD and its risk factors. Moreover, it demonstrates the mediating effect of the ApoB/ApoA1 ratio in CMD and its risk factors. These findings suggest that the ApoB/ApoA1 ratio may serve as a potential indicator for identifying the risk of developing CMD in participants.

Oxidative stress-related genetic variation and antioxidant vitamin intake in intact and ruptured abdominal aortic aneurysm: a Swedish population-based retrospective cohort study

AIMS

The aim of this study is to investigate how genetic variations in genes related to oxidative stress, intake of antioxidant vitamins, and any potential interactions between these factors affect the incidence of intact abdominal aortic aneurysm (AAA) and its rupture (rAAA), accounting for sex differences where possible.

METHODS AND RESULTS

The present retrospective cohort study (n = 25 252) uses baseline single-nucleotide polymorphisms (SNPs) and total antioxidant vitamin intake data from the large population-based, Malmö Diet and Cancer Study. Cumulative incidence of intact AAA was 1.6% and of rAAA 0.3% after a median follow-up of 24.3 years. A variant in NOX3 (rs3749930) was associated with higher rAAA risk in males [adjusted hazard ratio (aHR): 2.49; 95% confidence interval (CI): 1.36-4.35] and the overall population (aHR: 1.88; 95% CI: 1.05-3.37). Higher intakes of antioxidant vitamins, riboflavin, and folate were associated with 20% and 19% reduced intact AAA incidence, respectively. Interestingly, the inverse associations between riboflavin and vitamin D intake with intact AAA incidence were stronger in the individuals carrying the NOX3 variant as compared with the wild-type recessive genotype, i.e. by 60% and 66%, respectively (P for interaction < 0.05). Higher riboflavin intake was associated with a 33% male-specific intact AAA risk reduction, while higher intake of vitamin B12 intake was associated with 55% female-specific intact AAA risk increase; both these associations were significantly modified by sex (P for interaction < 0.05).

CONCLUSIONS

Our findings highlight the role of oxidative stress genetic variations and antioxidant vitamin intake in AAA. Although a low AAA/rAAA sample size limited some analyses, especially in females, our findings highlight the need for future randomized controlled trials and mechanistic studies, to explore the potential benefits of antioxidant vitamins while accounting for genetic and sex differences.

High-density lipoprotein cholesterol to apolipoprotein A-1 ratio is an important indicator predicting in-hospital death in patients with acute coronary syndrome

BACKGROUND

Dyslipidemia plays a pivotal role in the pathogenesis of acute coronary syndrome (ACS). This study aims to investigate the value of two indices associated with lipid metabolism, low-density lipoprotein cholesterol to apolipoprotein B ratio (LBR) and high-density lipoprotein cholesterol to apolipoprotein A-1 ratio (HAR), to predict in-hospital death in patients with ACS.

METHODS

This single-center, retrospective, observational study included 3,366 consecutive ACS patients in Zhongda Hospital, Southeast University from July 2013 to January 2018. The clinical and laboratory data were extracted, and the in-hospital death and hospitalization days were also recorded.

RESULTS

All patients were equally divided into four groups according to quartiles of HAR: Q1 (HAR < 1.0283), Q2 (1.0283 ≤ HAR < 1.0860), Q3 (1.0860 ≤ HAR < 1.1798), and Q4 (HAR ≥ 1.1798). Overall, HAR was positively associated with the counts of neutrophils and monocytes, whereas negatively correlated to lymphocyte counts. HAR was negatively correlated to left ventricular ejection fraction (LVEF). Compared to other three groups, in-hospital mortality (vs. Q1, Q2, and Q3, p < 0.001) and hospitalization length (vs. Q1, Q2, and Q3, p < 0.001) were significantly higher in the Q4 group. When grouped by LBR, however, there was no significant difference in LVEF, in-hospital mortality, and hospitalization length among groups. After adjusting potential impact from age, systolic blood pressure, creatine, lactate dehydrogenase, albumin, glucose, and uric acid, multivariate analysis indicated that HAR was an independent factor predicting in-hospital death among ACS patients.

CONCLUSIONS

HAR had good predictive value for patients' in-hospital death after the occurrence of acute coronary events, but LBR was not related to in-hospital adverse events.

Prospective Comparison of Plasma Biomarker and Traditional Risk Factor Profiles for Incident Isolated Atherosclerotic Disease and Incident Isolated Abdominal Aortic Aneurysm

Background: Traditional risk factors for atherosclerotic disease (AD) are well-known, of which some are relevant also for abdominal aortic aneurysms (AAA). The present study compares the importance of plasma biomarkers and traditional risk factor profiles for incident AD without concomitant AAA (isolated AD) and AAA without concomitant AD (isolated AAA) during long-term follow-up.

Methods: In the Malmö Diet and Cancer Study—cardiovascular cohort, 5,381 participants were free from atrial fibrillation or flutter, AD (coronary artery disease, atherothrombotic ischemic stroke, carotid artery disease, or peripheral artery disease), and AAA underwent blood sampling under standardized fasting conditions between 1991 and 1994. Cox proportional hazards regression analysis was used to calculate hazard ratios (HR) with 95% CIs.

Results: During a median follow-up of 23.1 years, 1,152 participants developed isolated AD, and 44 developed isolated AAA. Adjusted HR for lipoprotein-associated phospholipase A2 (mass) (HR 1.53, 95% CI 1.14–2.04 vs. HR 1.05, 95% CI.99–1.12) was higher for incident isolated AAA compared to incident isolated AD, respectively. Mid-regional pro-adrenomedullin (MR-proADM) was associated with incident isolated AD (HR 1.17, 95% CI 1.1–1.25) and incident isolated AAA (HR 1.47, 95% CI 1.15–1.88). MR-proADM was correlated (r = 0.32; p < 0.001) to body mass index (BMI), and BMI was associated with increased risk of incident isolated AAA (HR 1.43, 95% CI 1.02–2). No participant with diabetes mellitus (DM) at baseline developed isolated AAA (0/44), whereas DM was associated with an increased risk of isolated AD (HR 2.57, 95% CI 2.08–3.18). Adjusted HR for male sex (HR 4.8, 95% CI 2.42–9.48, vs. HR 1.76, 95% CI 1.56–1.98) and current smoking (HR 4.79, 95% CI 2.42–9.47 vs. HR 1.97, 95% CI 1.73–2.23) were higher in the incident isolated AAA group compared to the incident isolated AD group, respectively.

Conclusions: The data supports the view that components of vascular inflammation and cardiovascular stress drives AAA development, whereas glycated cross-links in abdominal aortic wall tissue may have a plausible role in reducing AAA risk in individuals with DM.