Tobacco smoking and the risk of abdominal aortic aneurysm: a systematic review and meta-analysis of prospective studies

Genetic and epigenetic regulation of abdominal aortic aneurysms

Abdominal aortic aneurysms (AAAs) are focal dilations of the aorta that develop from degenerative changes in the media and adventitia of the vessel. Ruptured AAAs have a mortality of up to 85%, thus it is important to identify patients with AAA at increased risk for rupture who would benefit from increased surveillance and/or surgical repair. Although the exact genetic and epigenetic mechanisms regulating AAA formation are not completely understood, Mendelian cases of AAA, which result from pathologic variants in a single gene, have helped provide a basic understanding of AAA pathophysiology. More recently, genome wide associated studies (GWAS) have identified additional variants, termed single nucleotide polymorphisms, in humans that may be associated with AAAs. While some variants may be associated with AAAs and play causal roles in aneurysm pathogenesis, it should be emphasized that the majority of SNPs do not actually cause disease. In addition to GWAS, other studies have uncovered epigenetic causes of disease that regulate expression of genes known to be important in AAA pathogenesis. This review describes many of these genetic and epigenetic contributors of AAAs, which altogether provide a deeper insight into AAA pathogenesis.

Abdominal aortic aneurysm in prostate cancer patients: the "road map" from incidental detection to advanced predictive, preventive, and personalized approach utilizing common follow-up for both pathologies

Abdominal aortic aneurysm (AAA) is often a hidden pathological process showing no clinical symptoms. Genetic burden, smoking, male gender, age > 65 years, and white race have been identified as the main risk factors. A regular screening program has been introduced but is, as yet, unclear and is not performed in most countries. Prostate cancer is the most frequent male malignant disease in Western countries. Prostate cancer is a disease of older age with a median primary diagnosis of over 60 years. In recent years, advanced imaging methods have been established as important diagnostic tools in prostate cancer diagnostics. The incidental detection of AAA during diagnostic imaging performed due to prostate cancer diagnosis could reveal some asymptomatic aneurysms. Using our experience, the incidental detection of AAA during 18F-fluoromethylcholine PET/CT imaging, performed due to the staging, follow-up, and restaging of the prostate cancer, was reworked into a regular tool of secondary prevention within the framework of personalized medicine strategies. Experience with this type of AAA detection is demonstrated by a cohort of 500 patients who underwent 18F-fluorometylcholine PET/CT examination due to the staging or restaging of prostate cancer. A total of 28 aneurysms were detected (26 aneurysms < 50 mm, 2 aneurysms > 50 mm). In 2 cases (diameter < 50 mm), serious complications were found (penetrating aortic ulcer). The detection and monitoring of AAA in patients undergoing 18F-fluorometylcholine PET/CT due to the prostate cancer offers the possibility of a secondary prevention of AAA, patient stratification, and common follow-up for both pathologies.

Symptoms of Depression and Risk of Abdominal Aortic Aneurysm: A HUNT Study

Background

Depression is associated with cardiovascular diseases, but the evidence is scarce regarding depression and risk of abdominal aortic aneurysms (AAA). The aim was to determine whether individuals with depressive symptoms have increased risk of AAA.

Methods and Results

This population‐based prospective study included 59 136 participants (52.4% women) aged 50 to 106 years from the HUNT (Norwegian Nord‐Trøndelag Health Study). Symptoms of depression were assessed using the depression subscale of the Hospital Anxiety and Depression Scale (HADS). During a median follow‐up of 13 years, there were 742 incident cases of AAA (201 women). A total of 6401 individuals (12.3%) reported depressive symptoms (defined as HADS depression scale [HADS‐D]) ≥8) (52.5% women). The annual incidence rate of AAA was 1.0 per 1000 individuals. At all ages, the estimated proportion of individuals diagnosed with AAA was higher among those with depressive symptoms (log‐rank test, P<0.001). People with HADS‐D ≥8 were older than those with HADS‐D<8 (median 57.8 versus 52.3 years, P<0.001) and a statistically significantly higher proportion of them (P<0.001) were smokers, overweight or obese, and reported a history of coronary heart disease, diabetes mellitus, and hypertension. In a Cox proportional hazard regression model adjusted for these factors, individuals with depressive symptoms had a ≈30% higher risk of AAA than those without (hazard ratio, 1.32, 95% CI 1.08–1.61, P=0.007).

Conclusions

This study shows that individuals with depressive symptoms have significantly higher risk of incident AAA, after adjustments for established risk factors.

Identification of novel diagnostic and prognostic biomarkers for abdominal aortic aneurysm

Aims

Abdominal aortic aneurysm is a life-threatening condition due to the risk of aneurysm growth and rupture. There are no approved diagnostic or prognostic biomarkers for abdominal aortic aneurysm. We aimed to identify diagnostic and prognostic biomarkers for abdominal aortic aneurysm and to investigate their relationship with abdominal aortic aneurysm diameter and growth.

Methods

In this case-control study, patients were included from an abdominal aortic aneurysm screening study on men aged ≥65 years. Of 24,589 examined men, 415 had abdominal aortic aneurysm, out of whom 134 consented to participate in the present study. One hundred and thirty-six screened men with aortic diameter <30 mm, matched for comorbidities and time of sampling were included as non-abdominal aortic aneurysm patients. Ninety-one cardiovascular specific proteins in plasma samples were measured by the Proseek Multiplex CVD III96x96panel.

Results

After Bonferroni correction, plasma levels of 21 proteins associated with proteolysis, oxidative-stress, lipid metabolism, and inflammation were significantly increased, whereas levels of paraoxonase 3, associated with high-density lipoprotein metabolism, were decreased in abdominal aortic aneurysm patients. Combination of growth/differentiation factor 15 and cystatin B had the best ability to discriminate abdominal aortic aneurysm from non-abdominal aortic aneurysm (area under the curve, 0.76; sensitivity, 80% and specificity, 52%). Myeloperoxidase showed the best prognostic value (area under the curve, 0.71; sensitivity, 80% and specificity, 59%) and higher baseline levels of myeloperoxidase were significantly associated with faster abdominal aortic aneurysm growth compared with lower levels, independent of baseline diameter.

Conclusions

We have identified multiple proteins associated with abdominal aortic aneurysm diameter and growth with a potential to become novel diagnostic and prognostic biomarkers for abdominal aortic aneurysm.

Intake of fibre and plant foods and the risk of abdominal aortic aneurysm in a large prospective cohort study in Sweden

Purpose

The purpose of this study was to investigate fibre, and plant foods, and its association with AAA risk.

Methods

In this prospective cohort study, Malmö Diet and Cancer Study, baseline data collection was carried out 1991–1996. The study participants’ (n = 26,133) dietary habits were extensively recorded at baseline. The specific diagnosis of AAA in the in-hospital registry was found valid in 95%. The association between plant foods, such as cereals and types of vegetables, and AAA was assessed by using Cox regression analysis expressed as hazard ratios (HR) with 95% confidence intervals (CI).

Results

A high intake of fibre was independently associated with AAA risk (HR per quintile 0.87, 95% CI 0.79–0.97). High intake of vegetables (HR 0.91, 95% CI 0.84–0.98), specifically leaf vegetables (HR 0.87, 95% CI 0.81–0.94), and fruits and berries (HR 0.89, 95% CI 0.82–0.96), citrus (HR 0.91, 95% CI 0.85–0.98) and non-citrus fruits (HR 0.87, 95% CI 0.81–0.95) were independently associated with a decreased AAA risk.

Conclusions

A high intake of fruits and berries and vegetables, in particular leaf vegetables, are associated with a decreased risk of developing AAA.

Electronic supplementary material

The online version of this article (10.1007/s00394-019-02054-w) contains supplementary material, which is available to authorized users.

Blood pressure, hypertension and the risk of abdominal aortic aneurysms: a systematic review and meta-analysis of cohort studies

Abdominal aortic aneurysms (AAA) are fatal in 80% of the cases when ruptured. Hypertension has been considered a potential risk factor for AAA; but the findings from prospective cohort studies have not been entirely consistent, nor have they been summarised in a comprehensive meta-analysis. Our aim was to conduct a systematic review and meta-analysis of cohort studies of the association between blood pressure, hypertension and AAA to clarify the strength and shape of these associations. We searched PubMed and Embase databases for relevant cohort studies up to April 30th, 2018. Random-effects models were used to calculate summary relative risks (RRs) and 95% confidence intervals (CIs). The meta-analysis included 21 cohort studies (20 publications) with data on 28,162 cases and 5,440,588 participants. The findings indicate that the RR of AAA in hypertensive patients is 1.66 times (95% CI: 1.49–1.85, I² = 79.3%, n = 13) that of non-hypertensive patients. In addition, there was a 14% (95% CI: 6–23%, I² = 30.5%, n = 6) and a 28% (95% CI: 12–46%, I² = 80.1%, n = 6) increase in the RR of AAA for every 20 mmHg and 10 mmHg increase in systolic blood pressure (SBP) and diastolic blood pressure (DBP), respectively. The analysis of DBP showed evidence of a strong and highly significant nonlinear dose–response relationship (p < 0.001) with a steeper association from 80 mmHg and above. This meta-analysis suggests that hypertension increases the risk of developing AAA by 66%. Further studies are needed to clarify the underlying mechanism explaining the much stronger association between DBP and AAA than for SBP.