The Study About Abdominal Aortic Aneurysm Related Risk

Abdominal aortic aneurysm (AAA) is one of the most catastrophic arterial disease, with the final outcome of aortic rupture due to the weakness of arterial wall. Over90%rupture cases result in sudden death. The average diameter of AAA increases4mm annually, and symptomatic AAAs rupture within2years after diagnosis confirmed. With the improvement of technique and life span, the incidence rate of AAA increasing every year. Although the exact pathological mechanism of AAA is not clear, male gender, hypertension, smoking and connective tissue disease are considered as relevant risk factors of AAA. Generally speaking, the interaction between arterial wall weakness and unstable hemodynamics may be the leading cause of AAA. Further study should focus on the new risk factors and potential pathogenesis.Objective:1) Retrospective analyzed the risk factors and clinical characteristics of AAA based on patient history, lab tests and CT scans, and explore the new factors;2) Comparative study between the new risk factors of aortic dilation and classic risk factors of atherosclerosis.Part1. Risk factors and clinical characteristics of AAAMethods519AAA patients treated in the department of vascular surgery, Changhai hospital during2001to2012were included, all the cases were confirmed by CTA, MRA or DSA. Another614patients without AAA were included from the second military medical university medical center during the same period. All the cases with infection, connective tissue diseases and auto-immune diseases were excluded.Comparative study was performed based on18factors selected from the preliminary experiment, and the clinical characteristics and relevant risk factors of AAA were analyzedMeans (±SD) were used to describe continuous variables and categorical variables are expressed as percentages in this article. A χ-test was performed for categorical variables. Univariate associations between all risk factors were calculated by logistic regression analysis. A P value<0.05was considered to indicate statistical significance. All analyses were performed using SPSS for Windows (SPSS Inc., Version17.0, Chicago, IL, USA).Results1. Smoking, inguinal hernia, PAD, COPD, systolic blood pressure and LP(a) were positively related with AAA, while diabetes was negatively related with AAA.2. Male gender carried a higher incidence of AAA, along with increased smoking prevalence and systolic blood pressure level. Patients over70carried a higher incidence of hepatic cysts and systolic blood pressure, which was also positively correlated with the diameter of AAA.Conclusion1. Smoking, inguinal hernia, PAD, COPD, systolic blood pressure and LP(a) were risk factors in AAA, while diabetes was a protective factor for AAA.2. Male gender carried a higher incidence of AAA, along with increased systolic blood pressure level. Patients over70carried a higher incidence of hepatic cysts and systolic blood pressure. Increased systolic blood pressure was a risk factor for AAA diameter.Part2. Risk factors for abdominal aortic dilationMethods:395patients with atherosclerosis or classic risk factors for cardiovascular diseases were included. All the cases with infection, cancer, secondary hypertension and dilated aortic diseases were excluded.Comparative study was performed to confirm the relevant risk factors in infrarenal abdominal aortic dilation.Associations between all risk factors were calculated by multiple linear regression analysis. A P value<0.05was considered to indicate statistical significance. All analyses were performed using SPSS for Windows (SPSS Inc., Version17.0, Chicago, IL, USA).Results:Body height, diastolic blood pressure, drinking, LP(a) and COPD were positively related with the diameter of abdominal aorta, while diabetes was negatively related with that.Conclusion: Body height, diastolic blood pressure, drinking, LP(a) and COPD were risk factors in abdominal aortic dilation, while diabetes was a protective factor for abdominal aortic dilation..