Prevalence of abdominal aortic aneurysms in over 65-year-old men with inguinal hernias

Do Hernias Contribute to Increased Severity of Aneurysmal Disease among Abdominal Aortic Aneurysm Patients?

Background  Connective tissue disorders could contribute to the pathogenesis of both abdominal aortic aneurysms (AAA) and hernias. We tested the hypothesis that hernias in AAA patients contribute to increased severity of the aneurysmal disease.

Methods  A questionnaire was used to collect information from 195 AAA patients divided into four groups: (1) survivors ( n  = 22) of ruptured AAA, (2) patients ( n  = 90) after elective open repair, (3) patients ( n  = 43) after elective endovascular repair (EVAR), and (4) patients ( n  = 40) under surveillance of AAA. The control group consisted of 100 patients without AAA whose abdominal computed tomography (CT) scans were examined for the presence of hernias. Mann–Whitney U -test, Chi-squared ( χ² ) test, or Fisher's exact test (as appropriate) were used for statistical analyses. Multivariate logistic regression was used to control for potential confounding variables such as sex and age.

Results  The prevalence of inguinal hernias was significantly higher in the AAA than the control group (25 vs. 9%, p  = 0.001) and did not differ between the AAA subgroups (9, 24, 35, and 23% in subgroups 1 through 4, respectively, p  = 0.15) based on univariate analysis. The prevalence of inguinal hernias did not differ ( p  = 0.15) between the two open surgery groups (groups 1 and 2), or when comparing all three operative procedures as a combined group to group 4 ( p  = 0.73). The prevalences of incisional hernias were 18 and 24% for groups 1 and 2, respectively, with no significant difference ( p  = 0.39). Inguinal hernia demonstrated a significant association with AAA on multivariate analysis ( p  = 0.006; odds ratio [OR] = 4.00; 95% confidence interval [CI] = 1.49–10.66).

Conclusions  Our study confirms previous observations that patients with AAA have a high prevalence of hernias. Our results suggest that hernias do not contribute to increased severity of the aneurysmal disease.

Abdominal aortic aneurysms and abdominal wall hernias - a systematic review and meta-analysis

Background: Abdominal wall hernias (AWHs) share common epidemiological characteristics with abdominal aortic aneurysms (AAAs), typically presenting in male population and older ages. Prior reports have associated those two disease entities. Our objective was to perform a systematic review and meta-analysis and examine whether AAA rates are higher among patients with AWH vs controls and whether the incidence of AWH was higher among patients with AAA vs patients without AAA. Methods: We performed a systematic review and meta-analysis according to the PRISMA guidelines. The Medline database was searched up to July 31, 2020. A random effects meta-analysis was performed. Results: In total, 17 articles and 738,972 participants were included in the systematic review, while 107,578 patients were eligible for the meta-analysis. Among four studies investigating the incidence of AAA in patients with hernias, AAA was more common in patients with hernias, compared to patients without hernias. [OR: 2.53, 95% CI: 1.24-5.16, I²=81.6%]. Among thirteen studies that compared patients with known AAA vs no AAA, the incidence of hernias was higher in patients with AAA, compared with patients without AAA [OR: 2.27, 95% CI: 1.66-3.09, I²=84.6%]. Conclusions: Our study findings indicate that a strong association between AWH and AAA exists. AWHs could therefore be used as an additional selection criterion for screening patients for AAA, apart from age, gender, family history and smoking.

Lack of association between inguinal hernia and abdominal aortic aneurysm in a population-based male cohort

Background

Previous studies have reported a higher prevalence of inguinal hernia in patients with abdominal aortic aneurysm (AAA). The aim of this study was to explore the association between inguinal hernia and AAA in a large population-based cohort of men who had screening for AAA.

Methods

A total of 18 331 men aged 65–76 years had ultrasound screening for AAA in the Central Region of Denmark from 2008 to 2010. The Danish National Patient Registry was interrogated, and screened men registered with an inguinal hernia from 1977 to 2011 were identified. The association between inguinal hernia and AAA was assessed by multiple logistic regression analysis.

Results

The prevalence of AAA was 3.3 per cent (601 of 18 331). A total of 2936 (16.0 per cent) of the 18 331 patients were registered with a diagnosis of inguinal hernia or hernia repair. Inguinal hernia was not associated with AAA: crude odds ratio (OR) 0.86 (95 per cent confidence interval 0.68 to 1.09) and adjusted OR 0.94 (0.75 to 1.20).

Conclusion

In contrast to smaller patient-based studies, this large population-based study found no association between inguinal hernia and AAA.

Abdominal aortic aneurysm and abdominal wall hernia as manifestations of a connective tissue disorder

BACKGROUND

Abdominal aortic aneurysms (AAAs) and abdominal wall hernias represent chronic degenerative conditions. Both aortic aneurysms and inguinal hernias share common epidemiologic features, and several investigators have found an increased propensity for hernia development in patients treated for aortic aneurysms. Chronic inflammation and dysregulation in connective tissue metabolism constitute underlying biological processes, whereas genetic influences appear to be independently associated with both disease states. A literature review was conducted to identify all published evidence correlating aneurysms and hernias to a common pathology.

METHODS

PubMed/Medline was searched for studies investigating the clinical, biochemical, and genetic associations of AAAs and abdominal wall hernias. The literature was searched using the MeSH terms "aortic aneurysm, abdominal," "hernia, inguinal," "hernia, ventral," "collagen," "connective tissue," "matrix metalloproteinases," and "genetics" in all possible combinations. An evaluation, analysis, and critical overview of current clinical data and pathogenic mechanisms suggesting an association between aneurysms and hernias were undertaken.

RESULTS

Ample evidence lending support to the clinical correlation between AAAs and abdominal wall hernias exists. Pooled analysis demonstrated that patients undergoing aortic aneurysm repair through a midline abdominal incision have a 2.9-fold increased risk of developing a postoperative incisional hernia compared with patients treated for aortoiliac occlusive disease (odds ratio, 2.86; 95% confidence interval, 1.97-4.16; P < .00001), whereas the risk of inguinal hernia was 2.3 (odds ratio, 2.30; 95% confidence interval, 1.52-3.48; P < .0001). Emerging evidence has identified inguinal hernia as an independent risk factor for aneurysm development. Although mechanisms of extracellular matrix remodeling and the imbalance between connective tissue degrading enzymes and their inhibitors instigating inflammatory responses have separately been described for both disease states, comparative studies investigating these biological processes in aneurysm and hernia populations are scarce. A genetic predisposition has been documented in familial and observational segregation studies; however, the pertinent literature lacks sufficient supporting evidence for a common genetic basis for aneurysm and hernia.

CONCLUSIONS

Insufficient data are currently available to support a systemic connective tissue defect affecting the structural integrity of the aortic and abdominal wall. Future investigations may elucidate obscure aspects of aneurysm and hernia pathophysiology and create novel targets for pharmaceutical and gene strategies for disease prevention and treatment.

Prevalence of Abdominal Wall Hernia in Participants With Abdominal Aortic Aneurysm Versus Peripheral Arterial Disease—A Population-Based Study

Small studies suggest an association between abdominal aortic aneurysms (AAAs) and hernias, possibly related to connective tissue weakness. We evaluated the association between AAA and abdominal wall hernia (AWH), using peripheral arterial disease (PAD) patients as controls, in Olmsted County, Minnesota. In a retrospective cohort study we queried the electronic medical records for the diagnosis of AAA. The resulting data were then queried for prevalence of AWH. The same set of queries was repeated for PAD. Occurrence of AWH in the 2 groups was compared using the chi-square test. Of the 187 151 patient records queried, 939 had AAA and 3465 had PAD. Abdominal wall hernia occurred in 157 (16.7%) patients with AAA and in 343 (9.9%) patients with PAD. Abdominal wall hernia was 1.7 times more prevalent in those with AAA versus PAD ( P < .0001). A history of hernia may prompt screening for AAA in some patients.

Increased prevalence of abdominal aortic aneurysm in patients undergoing inguinal hernia repair compared with patients without hernia receiving aneurysm screening

BACKGROUND

The introduction of screening programs for abdominal aortic aneurysm (AAA) is being contemplated by health services in several countries. The correlation between aortic aneurysm and abdominal wall hernias is well reported, and inguinal hernia has been identified as a risk factor for aortic aneurysm. However, the prevalence of AAA in patients with inguinal hernia has not been adequately documented. This study evaluated whether patients with inguinal hernia are at increased risk of having an AAA compared with patients without hernia receiving aneurysm screening.

METHODS

Men aged >55 undergoing primary inguinal hernia repair underwent ultrasound imaging of the abdominal aorta to screen for aneurysm. A reference group was selected from men without clinical evidence of inguinal hernia participating in an AAA screening program. Prevalence and odds ratios of AAA in the two groups were calculated.

RESULTS

The study cohort comprised 235 patients with inguinal hernia and 203 controls. The mean ± SD aortic diameter was 22 ± 9 mm in patients with inguinal hernia vs 20 ± 6 mm for controls (P = .045). The prevalence of AAA was 8.1% in the hernia group and 3.9% in the control group (adjusted odds ratio, 3.9; 95% confidence interval, 1.6-9.5; P = .039). For aneurysms >4 cm, the prevalence was 5.1% in those with an inguinal hernia and 1.5% in those without an inguinal hernia (adjusted odds ratio, 4.7; 95% confidence interval, 1.2-18.5, P = .025).

CONCLUSIONS

Inguinal hernia was a significant risk factor for AAA. Entry into a screening program of men aged >55 admitted for inguinal hernia repair should be considered.

Diastasis Recti and Abdominal Aortic Aneurysm

An association between abdominal aortic aneurysm (AAA) and abdominal wall hernia has been suggested, possibly reflecting a common collagen disorder. The same mechanism may also cause a greater frequency of diastasis recti among patients at risk of developing AAA. Diastasis recti could be used to identify patients at risk of AAA, with implications for AAA screening. The aim of this study was to determine whether an association between diastasis recti and AAA could be demonstrated.

The preoperative computed tomographic (CT) scans of 75 male patients undergoing elective AAA repair were retrospectively examined and linea alba width recorded at supraumbilical and subumbilical levels. Measurements were compared with controls frequency matched for age.

Fifty patients with AAA were observed to have supraumbilical diastasis recti on preoperative CT compared with 47 controls. Mean linea alba width was not significantly different between the two groups at either the supraumbilical (19.3 mm vs 20.7 mm, p = .45) or subumbilical (3.6 mm vs 4.3 mm, p = .43) level.

The findings do not support the hypothesis that the presence of diastasis recti can serve as an indication to select male patients for screening for AAA.