La diabetes mellitus como factor protector del aneurisma de aorta abdominal: posibles mecanismos

Causal relationship between type 2 diabetes mellitus and aortic dissection: insights from two-sample Mendelian randomization and mediation analysis

Objective

Some evidence suggests a reduced prevalence of type 2 diabetes mellitus (T2DM) in patients with aortic dissection (AD), a catastrophic cardiovascular illness, compared to general population. However, the conclusions were inconsistent, and the causal relationship between T2DM and AD remains unclear.

Methods

In this study, we aimed to explore the causal relationship between T2DM and AD using bidirectional Mendelian randomization (MR) analysis. Mediation MR analysis was conducted to explore and quantify the possible mediation effects of 1400 metabolites in T2DM and AD.

Results

The results of 26 datasets showed no causal relationship between T2DM and AD (P>0.05). Only one dataset (ebi-a-GCST90006934) showed that T2DM was a protective factor for AD (I9-AORTDIS) (OR=0.815, 95%CI: 0.692-0.960, P=0.014), and did not show horizontal pleiotropy (P=0.808) and heterogeneity (P=0.525). Vanillic acid glycine plays a mediator in the causal relationship between T2DM and AD. The mediator effect for vanillic acid glycine levels was -0.023 (95%CI: -0.066-0.021).

Conclusion

From the perspective of MR analysis, there might not be a causal relationship between T2DM and AD, and T2DM might not be a protective factor for AD. If a causal relationship does exist between T2DM and AD, with T2DM serving as a protective factor, vanillic acid glycine may act as a mediator and enhance such a protective effect.

Association of metformin use with abdominal aortic aneurysm: A systematic review and meta-analysis

BACKGROUND

Abdominal aortic aneurysm (AAA) is a cardiovascular disease characterized by a high mortality rate when ruptured. Some studies suggest a potential inverse correlation between AAA and diabetes patients, especially those undergoing metformin treatment. However, this relationship remains unclear. This paper offers a systematic review and meta-analysis with the objective of clarifying the influence of metformin on AAA.

METHODS

A search for relevant articles was performed across multiple databases including PubMed, ScienceDirect, Cochrane and Scopus. The focus was on studies that examined the comparative effects of metformin and non-metformin treatments on AAA patients. Data from appropriate studies were consolidated to estimate the effects. Our study encompassed 11 articles, comprising 13 cohorts that compared metformin (n = 32,250) with a control group (n = 116,339).

RESULTS

The random effects meta-analysis revealed that metformin was associated with a slower growth rate (weighted mean difference (WMD) -0.86 mm; 95% CI: -1.21 to -0.52; p < 0.01; I2: 81.4%) and fewer AAA-related events (OR: 0.54; 95% CI: 0.34 to 0.86; p = 0.01; I2: 60.9%). The findings suggest that metformin may be linked to a reduced risk of aortic aneurysm. A meta-regression analysis indicated that the association between metformin and AAA growth was significantly influenced by male gender (p = 0.027), but not by age (p = 0.801), hypertension (p = 0.256), DM (p = 0.689), smoking history (p = 0.786), use of lipid-lowering agents (p = 0.715), or baseline diameter (p = 0.291).

CONCLUSION

These results hint at a potential role for metformin in limiting annual AAA growth, AAA-related events, and the risk of AAA.

Protection of diabetes in aortic abdominal aneurysm: Are antidiabetics the real effectors?

Aortic aneurysms, including abdominal aortic aneurysms (AAAs), is the second most prevalent aortic disease and represents an important cause of death worldwide. AAA is a permanent dilation of the aorta on its infrarenal portion, pathologically associated with oxidative stress, proteolysis, vascular smooth muscle cell loss, immune-inflammation, and extracellular matrix remodeling and degradation. Most epidemiological studies have shown a potential protective role of diabetes mellitus (DM) on the prevalence and incidence of AAA. The effect of DM on AAA might be explained mainly by two factors: hyperglycemia [or other DM-related factors such as insulin resistance (IR)] and/or by the effect of prescribed DM drugs, which may have a direct or indirect effect on the formation and progression of AAAs. However, recent studies further support that the protective role of DM in AAA may be attributable to antidiabetic therapies (i.e.: metformin or SGLT-2 inhibitors). This review summarizes current literature on the relationship between DM and the incidence, progression, and rupture of AAAs, and discusses the potential cellular and molecular pathways that may be involved in its vascular effects. Besides, we provide a summary of current antidiabetic therapies which use could be beneficial for AAA.

[Abdominal aortic aneurysm ultrasound screening in men with risk factors in Primary Care]

OBJECTIVE

to describe the implantation of ultrasound screening for Abdominal Aortic Aneurysm (AAA) in our healthcare district in men from 65 to 79 years of age who have had an identifiable risk factor for developing AAA, such as smoking or a history thereof, hypertension, family history of aneurysms, aneurysms in other locations and clinical atherosclerosis, acute myocardial infarction, intermittent claudication, or stroke. Analyse the performance of said screening.

SETTING

Primary Care.

PARTICIPANTS AND INTERVENTIONS

656 patients were screened, representing 40% of the target population of 1,658 patients. The remaining part of the target population could not be screened because of the outbreak of the COVID-19 pandemic. 608 ultrasound examinations were performed.

MAIN MEASUREMENTS

coverage of the screening programme, prevalence of abdominal aortic aneurysms, prevalence of smoking and other risk factors in patients with/without aneurysms.

RESULTS

19 patients with ectatic aorta (25-29mm) and 11 with abdominal aortic aneurysms (1.81%) were found. 5 were active smokers (45%, compared to 20% in the entire sample) and 6 were former smokers. None of the aneurysm patients were non-smokers. 7 of them were hypertensive.

CONCLUSIONS

The prevalence of aneurysms in our sample was 2.6%, which was lower than expected. The wide use of ultrasound and its progressive generalisation in the Primary Care setting should lead to a decrease in the number of undiagnosed AAA.

AAA Revisited: A Comprehensive Review of Risk Factors, Management, and Hallmarks of Pathogenesis

Despite declining incidence and mortality rates in many countries, the abdominal aortic aneurysm (AAA) continues to represent a life-threatening cardiovascular condition with an overall prevalence of about 2-3% in the industrialized world. While the risk of AAA development is considerably higher for men of advanced age with a history of smoking, screening programs serve to detect the often asymptomatic condition and prevent aortic rupture with an associated death rate of up to 80%. This review summarizes the current knowledge on identified risk factors, the multifactorial process of pathogenesis, as well as the latest advances in medical treatment and surgical repair to provide a perspective for AAA management.

Exploring the Correlation and Protective Role of Diabetes Mellitus in Aortic Aneurysm Disease

Introduction: Diabetes mellitus is recognised as a significant risk factor for cardiovascular and peripheral vascular disease, as the abnormal metabolic state increases the risk for atherosclerosis, occlusive arterial disease and vascular dysfunction. There have been reports of potential association across the literature that illustrates a link between diabetes mellitus and aortic aneurysm, with the former having a protective role on the development of the latter.

Methods: A thorough literature search was performed through electronic databases, to provide a comprehensive review of the study's reporting on the association of diabetes mellitus and aortic aneurysm, discussing the mechanisms that have been reported; furthemore, we reviewed the reports of the impact of oral hypoglycameic agents on aortic aneurysms.

Results: Various proposed mechanisms are involved in this protective process including endothelial dysfunction, chronic hyperglycemia and insulin resistance. The evidence suggests a negative association between these disease process, with prevelance of diabetes mellitus resulting in lower rates of aortic aneurysm, via its protective mechanistic action. The increase in advanced glycation end products, increased arterial stiffness and vascular remodelling seen in diabetes, was found to have a profound impact on aneurysm development, its slow progression and lower rupture rate in these individuals. This review has also highlighted the role of oral hypoglycaemic agents having a protective effect against AA disease.

Conclusion: A decrease in development, progression and mortality from aortic aneurysms as well as reduced rates of dissection, have been observed in those with diabetes. This review has provided a comprehensive insight on the effect of diabetes and its physiological processes, and elements of its con-committant treatment, having a protective role against these aortic diseases.

[Surgical treatment of patients with abdominal aortic aneurysm and ischaemic heart disease]

Presented herein are the results of treatment of 137 patients with infrarenal aneurysms of the abdominal portion of the aorta in a combination with ischaemic heart disease. Severity of lesions to the coronary bed and the risk of cardiac complications were assessed according to the SYNTAX score. Depending on severity of angina pectoris and the clinical course of infrarenal aortic aneurysms, we used different tactical approaches to operative treatment of patients. In a low risk of coronary complications, we performed isolated prosthetic repair or endoprosthetic reconstruction of the abdominal aorta. In patients with haemodynamically significant lesions of the coronary bed and positive non-invasive tests, the first stage consisted in coronary artery bypass grafting or stenting of coronary arteries taking into account the risk of cardiac complications according to the SYNTAX Score. The second stage consisted in prosthetic repair or endoprosthetic reconstruction of the abdominal aorta. The terms of the second stage differed and were determined by the course of abdominal aortic aneurysms. In symptomatic large aneurysms (more than 8 cm), prosthetic repair of the abdominal aorta was carried out within 2 weeks after previous stenting of coronary arteries. Simultaneous myocardial revascularization and abdominal aortic reconstruction were performed only in patients with severe angina pectoris, lesions of the trunk of the left coronary artery, three-vessel lesions of the coronary bed, high risk of cardiac complications according to the SYNTAX Score and a complicated or symptomatic course of an infrarenal aortic aneurysm. During implantation of stent grafts into the abdominal aorta there were neither lethal outcomes nor cardiac complications. In open operations, the 30-day mortality rate amounted to 2.2%, with the 5-year survival rate of 92%.

The potential role of plasma fibroblast growth factor 21 as a diagnostic biomarker for abdominal aortic aneurysm presence and development

AIMS

Fibroblast growth factor 21 (FGF21) has been identified as the master hormonal regulator of energy balance, its elevation is observed in a series of metabolic and cardiovascular diseases. Studies have implicated the role of FGF21 signaling in the pathogenesis of abdominal aortic aneurysm (AAA). We will investigate the association of FGF21 and AAA development.

MATERIALS AND METHODS

In this study, we assayed plasma levels of FGF21 in 82 patients with AAA and 44 control subjects, then analyzed their relationship with clinical, biochemical and histological phenotypes. The expression of β-klotho, an essential co-receptor of FGF21, was assessed with IHC staining and RT-qPCR. Machine learning models incorporate a combination of FGF21 and clinical data were utilized in the prediction of AAA occurrence.

KEY FINDINGS

FGF21 was statistically higher in patients with AAA (781 pg/ml [533, 1213]) than in control subjects (567 pg/ml [324, 939]). After adjustment for age and BMI, we found a positive association of FGF21 levels with AAA diameters, hypertension rate and hsCRP, and a negative correlation between FGF21 levels and HDL-c. Furthermore, the protein levels of β-klotho in abdominal aorta of AAA were found significantly lower than in control group indicating the presence of FGF21 resistance. Combining FGF21 levels with four clinical characteristics significantly improved the stratification of AAA and control groups with an AUC of 0.778.

SIGNIFICANCE

Combining detection of plasma FGF21 and clinical characteristics may be reliable for identifying the presence of AAA. The role of FGF21 as a therapeutic target of AAA warrants further investigation.

Insight into the expression of toll-like receptors 2 and 4 in patients with abdominal aortic aneurysm

An abdominal aortic aneurysm (AAA) is a relatively common, life-threatening disease prevalent in persons over the age of 65. In recent years, an increasing number of studies have suggested that pattern-recognition receptors (PRRs), including Toll-like receptors (TLRs), may serve as important regulators in the development of AAAs. In this study, we evaluated the TLR2 and TLR4 expression in the aortic wall and blood of patients with AAA. The TLR2 and TLR4 mRNA expression were significantly higher in the blood of patients with AAA than in the blood of healthy volunteers (p = 0.009 and p = 0.010, respectively). The expression of TLR2 and TLR4 transcripts was also higher in the blood compared with the aortic wall tissue of AAA patients (p = 0.001 for both). Higher TLR2 protein expression was observed in the aortic wall of AAA patients compared with the blood (p = 0.026). A significantly higher concentration of TNF-α and IL-4 in patients with AAA than in healthy volunteers (p < 0.001 for both) was noticed. This study suggests that TLR2 may play a role in the inflammatory response in the aorta, both locally and systemically, in patients with AAA.