|Year : 2019 | Volume
| Issue : 4 | Page : 133-137
Prevalence of abdominal aorta aneurysm and associated risk factors in Abha city, Saudi Arabia
Abdullah Alhaizaey, Ahmed Azazy, Mohammed Asiry, Mohammed Alsayed, Mustafa Abbass, Abdulrhman Hassan, Ahmed Gamil, Musaed Alghamdi
Division of Vascular Surgery, Aseer Central Hospital, King Khalid University, Abha, Saudi Arabia
|Date of Submission||17-Apr-2019|
|Date of Acceptance||16-Sep-2019|
|Date of Web Publication||12-Dec-2019|
Aseer Central Hospital, P. O. Box 34, Abha 61321
Source of Support: None, Conflict of Interest: None
Objective: The objective was to assess the prevalence and risk factors of abdominal aorta aneurysms (AAAs) in the general population.
Materials and Methods: We carried out a prospective, interventional study with patients aged over 60 years screened in the Asir Central Hospital Vascular Department from March 2017 to March 2018. Ultrasound was used to AAA screening. The maximal anteroposterior (AP) and transverse (LL) diameters of the suprarenal and infrarenal aorta were measured in each patient. AAA was defined as aortic dilatation >29 mm in the AP or LL plane. All cases with an aortic diameter >25 mm were included in the study.
Results: Our study included 701 patients (531 male, 170 female; age 60–102 years). Most were Saudi nationals (87.6%). There were some smokers (1.3%), 277 (39.5%) had diabetes mellitus, and 233 (31.8%) had hypertension. Fifty-one percent of patient had ischemic heart disease (7.3%), and 13.4% had hypercholesterolemia. Patients were classified into three groups: normal aortic size of 657 patients (93.7%); aortic ectasia 26–29 mm of 24 patients (3.4%); and AAA ≥30 mm of 20 patients (2.9%). The overall prevalence of AAA was ≥30 mm (2.9%) and there is significant relation with hypertension (P < 0.05).
Conclusion: Asymptomatic AAA is prevalent in our area. We may need to implement a regular screening program for men aged >60 years, especially high-risk patients to reduce AAA rupture, emergency AAA repair, and mortality.
Keywords: Abdominal aortic aneurysm, prevalence, risk factor, screening, ultrasound
|How to cite this article:|
Alhaizaey A, Azazy A, Asiry M, Alsayed M, Abbass M, Hassan A, Gamil A, Alghamdi M. Prevalence of abdominal aorta aneurysm and associated risk factors in Abha city, Saudi Arabia. Saudi Surg J 2019;7:133-7
|How to cite this URL:|
Alhaizaey A, Azazy A, Asiry M, Alsayed M, Abbass M, Hassan A, Gamil A, Alghamdi M. Prevalence of abdominal aorta aneurysm and associated risk factors in Abha city, Saudi Arabia. Saudi Surg J [serial online] 2019 [cited 2020 Apr 9];7:133-7. Available from: http://www.saudisurgj.org/text.asp?2019/7/4/133/272846
| Introduction|| |
Abdominal aorta aneurysm (AAA) is a dilated aorta 1.5 times more than normal aorta at the level of the renal arteries, or an AAA is diagnosed when the aortic diameter exceeds 3.0 cm.
The risk of AAAs increases dramatically in the presence of the following factors: age ≥60 years, hypertension, and smoking. The likelihood that an aneurysm will rupture depends on aneurysm size, continued smoking, expansion rate, and persistent hypertension. Most of AAAs discovered incidentally while the patient underwent radiological investigations due to other purposes.
The prevalence of AAA has been increasing for the past two decades, which possibly correlates to the increased average life span and development of diagnostic tools and screening programs. The prevalence of AAA is 1%–7% in Western population and 5% in men over 65 years of age. A ruptured AAA can be fatal; therefore, a screening program is recommended for populations at increased risk.
Epidemiological studies of AAA have shown that the annual incidence of new AAA diagnoses is approximately 0.4%–0.67% in Western population, despite the evolution of our understanding and treatment of AAA in the past few decades, it continues to be a major threat to health because it has an overall mortality of 80% in the event of rupture. Early identification of patients with AAA and offer of timely elective repair remains to be the most reliable strategy for prevention of death from ruptured AAA.
Ultrasonography is accepted as the standard screening method for AAA because it has a high sensitivity (94%–100%) and specificity (98%–100%) and has no radiation exposure.
Surgical repair and endovascular aneurysm repair have similar outcomes, but endovascular repair is lower perioperative mortality and less invasive than surgical repair.
This study was designed to assess the prevalence of AAA in Abha, Saudi Arabia. In addition, the study aimed to define risk factors associated with high prevalence of the disease, to provide information concerning which subset of individuals from the population could benefit from screening.
Statistical analysis was done using IBM SPSS software version 20 Description of quantitative data was done by mean and standard deviation (SD), and for qualitative data, percentage was used. Chi-square test was used to compare qualitative data between groups, and t-test was used to compare quantitative data between groups. Odds ratio (OR) with 95% confidence interval (CI) was used to describe degree of association between variables.
| Materials and Methods|| |
We carried out a prospective, interventional study in which participants were screened in the Asir Central Hospital Vascular Department using ultrasound to screen for AAA from March 2017 to March 2018.
Males and females aged ≥60 years were included in the study. The study was explained to the participants; those who agreed to participate were first interviewed according to a survey that covered medical history, current therapy, smoking, and basic clinical data (blood pressure, heart rate, body weight, and height); any required additional tests were ordered accordingly.
Abdominal ultrasound scan was performed on all patients by a specialized radiologist from our hospital using B-mode ultrasonography machine. The maximal anteroposterior (AP) and transverse (LL) diameters of the suprarenal and infrarenal aorta were measured in each patient. AAA was defined as any aortic dilatation >29 mm in the AP or the LL plane. All cases with an aortic diameter >25 mm were registered. Ultrasound surveillance for patients with AAAs can be done regularly every 12 months for aneurysm 3–4 cm, every 6 months for aneurysm 4–4.5 cm, and every 3 months for aneurysm >4–5 cm. The aneurysms reaching a diameter of 5.5 cm in male and 5 cm in female, aneurysms with an expansion rate >5 mm in 6 months, and symptomatic patients were evaluated for management with computed tomography with arterial phase contrast.
| Results|| |
A total of 701 patients (531 males and 170 females) were included in the study. Their ages ranged from 60 to 102 years with a mean ± SD (68.1 ± 10 years). The majority of them were Saudi nationals (87.6%). Few were smokers (1.3%), 277 (39.5%) had a history of diabetes mellitus (DM), and 233 (31.8%) had a history of hypertension. Ischemic heart disease (IHD) was present in 51 patients (7.3%), and 13.4% of the patients had hypercholesterolemia [Table 1].
Based on the abdominal ultrasound results, patients were classified into three groups: normal aortic size of 657 patients (93.7%), aortic ectasia 26–29 mm of 24 patients (3.4%), and AAA ≥ 30 mm of 20 patients (2.9%). The AAA prevalence was 3.5% among females and 2.8% among males [Table 1].
Among the risk factors for AAA, hypertension was significantly related to the presence of AAA (P < 0.05; OR: 3.3; 95% CI: 1.3–8.3). Among patients with AAA, 60% were hypertensive compared to 30% of the normal participants. Other risk factors such as age, gender, nationality, smoking, DM, hypercholesterolemia, IHD, history of vascular disease, medications, and family history of AAA were not significantly related to the presence of AAA [Table 2].
| Discussion|| |
AAA screening decrease mortality due to AAA by 4/1000.,,, Moreover, in comparison of AAA screening with breast cancer and colorectal cancer screening program, it showed decrease mortality by 0.7/1000, whereas decrease mortality was 1.5/1000.
Despite this, as the national AAA screening program continues, the issue of a lower rate of AAA incidence persists, as does the question of targeting resources to improve yield and therefore success.
This study indicates a shortfall in uptake of screening in Abha, Saudi Arabia, among different races of both males and females aged ≥60 years. Results have shown a significant difference in the incidence of AAA between different age groups, patients with no risk factors and those with at least one cardiovascular, family, or lifestyle risk factor.
Our prevalence data are in keeping with those of that of literature. Our overall prevalence for AAA ≥ 30 mm (2.9%) is remarkably similar to that seen in the study by Mani et al.
There has been considerable interest in the long-term treatment of individuals with nonaneurysmal aortic diameters at screening. In multicenter aneurysm screening study, the rate of ruptured AAAs appeared to start increasing at approximately 8 years after baseline screening.
A multicenter study found that 26% of men and women with subaneurysmal aortic diameters of 2.5–2.9 cm developed an AAA larger than 5.4 cm in diameter within 10 years. Together, these studies suggest that men with aortic diameters in the 2.5 -to 2.9 cm range are at risk of incident AAAs although the benefit of surveillance of these men remains to be established. Interestingly, aortic diameters larger than 2.5 cm in men are also associated with future (nonaneurysmal) cardiovascular events.
Age has a dramatic effect on the incidence of AAA. In Rochester, USA, AAA incidence was essentially zero in individuals below the age of 49 years, increasing from 2.1 in the 40–49-year age group to 2.83 in those over 80 years of age. This was clear in our study, where the mean age was 68.1 years.
Men have 4–5 times risk chance to get AAAs in comparison with women according population-based studies. Surprisingly in our study, AAA prevalence was 3.5% among females and 2.8% among males [Table 1]. This pattern should be reviewed because our results were similar to those of a screening study performed in the Jeddah area by al-Zahrani et al.
The absence of a relationship between hypertension and AAA is consistent with data from several previous studies, whereas others found hypertension to be associated with AAA., In the large Aneurysm Detection and Management (ADAM) Study, hypertension was only marginally associated with AAA; in our study, we found a strong correlation between hypertension and AAA.
Unruptured aneurysms that are not repaired often gradually enlarge. The majority of aneurysms discovered in screening are small and do not require surgical repair, but need a regular surveillance. The risk of rupture generally increases as the diameter of the aneurysm increases. According to results of two recently published large AAA screening trials, the U.K. Small Aneurysm Trial and the ADAM study, the rupture risk of aneurysms that were 4.0–5.5 cm in diameter was 1.0% and 0.5%/year, respectively. In comparison, other older studies reported an annual rupture risk of 3.4% for aneurysms that were 5.0–5.9 cm in diameter. This necessitates regular surveillance, which was done in our cases.
| Conclusion|| |
The results of our screening study show a prevalence of asymptomatic AAA in a general population in our area, which is comparable to that of similar series carried out in other countries. We also conclude that implementation of a regular screening program for males aged above 60 years, especially high-risk patients, is required.
AAA screening program will help in the avoidance of AAA rupture, emergency AAA procedures, and death within 30 days of an AAA procedure and resulted in a significant decrease of morbidity and mortality for such diseases.
Decreasing of AAA-specific mortality rate after applying of the screening program may also be affected by other factors, including increased use of endovascular repair, falling prevalence of the disease, better perioperative outcome, and increased life expectancy.
However, despite a falling prevalence, contemporary AAA screening in men remains cost-effective because of counterbalancing the lower prevalence with improved surgical outcome and increased longevity.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Majeed K, Hamer AW, White SC, Pegg TJ, Wilkins GT, Williams SM, et al.
Prevalence of abdominal aortic aneurysm in patients referred for transthoracic echocardiography. Intern Med J 2015;45:32-9.
Aggarwal S, Qamar A, Sharma V, Sharma A. Abdominal aortic aneurysm: A comprehensive review. Exp Clin Cardiol 2011;16:11-5.
Acosta S, Ogren M, Bengtsson H, Bergqvist D, Lindblad B, Zdanowski Z. Increasing incidence of ruptured abdominal aortic aneurysm: A population-based study. J Vasc Surg 2006;44:237-43.
U.S. Preventive Services Task Force. Screening for abdominal aortic aneurysm: Recommendation statement. Ann Intern Med 2005;142:198-202.
Kim LG, Scott RA, Ashton HA, Thompson SG. Multicentre aneurysm screening study group. A sustained mortality benefit from screening for abdominal aortic aneurysm. Ann Intern Med 2007;146:699-706.
Gillum RF. Epidemiology of aortic aneurysm in the United States. J Clin Epidemiol 1995;48:1289-98.
Ashton HA, Buxton MJ, Day NE, Kim LG, Marteau TM, Scott RA, et al.
The multicentre aneurysm screening study into the effect of abdominal aortic aneurysm screening on mortality in men: A randomised controlled trial. Lancet 2002;360:1531-9.
Canadian Task Force on Preventive Health Care. Recommendations on screening for abdominal aortic aneurysm in primary care. CMAJ 2017;189:E1137-45.
van der Vliet JA, Boll AP. Abdominal aortic aneurysm. Lancet 1997;349:863-6.
Guirguis-Blake JM, Beil TL, Senger CA, Whitlock EP. Ultrasonography screening for abdominal aortic aneurysms: A systematic evidence review for the U.S. preventive services task force. Ann Intern Med 2014;160:321-9.
Thompson SG, Ashton HA, Gao L, Buxton MJ, Scott RA; Multicentre Aneurysm Screening Study Group. Final follow-up of the multicentre aneurysm screening study (MASS) randomized trial of abdominal aortic aneurysm screening. Br J Surg 2012;99:1649-56.
International AAA Screening Group, Björck M, Bown MJ, Choke E, Earnshaw J, Flørenes T, et al.
International update on screening for abdominal aortic aneurysms: Issues and opportunities. Eur J Vasc Endovasc Surg 2015;49:113-5.
Dabare D, Lo TT, McCormack DJ, Kung VW. What is the role of screening in the management of abdominal aortic aneurysms? Interact Cardiovasc Thorac Surg 2012;14:399-405.
Mani K, Alund M, Björck M, Lundkvist J, Wanhainen A. Screening for abdominal aortic aneurysm among patients referred to the vascular laboratory is cost-effective. Eur J Vasc Endovasc Surg 2010;39:208-16.
Wild JB, Stather PW, Biancari F, Choke EC, Earnshaw JJ, Grant SW, et al.
Amulticentre observational study of the outcomes of screening detected sub-aneurysmal aortic dilatation. Eur J Vasc Endovasc Surg 2013;45:128-34.
Duncan JL, Harrild KA, Iversen L, Lee AJ, Godden DJ. Long term outcomes in men screened for abdominal aortic aneurysm: Prospective cohort study. BMJ 2012;344:e2958.
Bickerstaff LK, Hollier LH, Van Peenen HJ, Melton LJ 3rd
, Pairolero PC, Cherry KJ, et al.
Abdominal aortic aneurysms: The changing natural history. J Vasc Surg 1984;1:6-12.
Arnell TD, de Virgilio C, Donayre C, Grant E, Baker JD, White R. Abdominal aortic aneurysm screening in elderly males with atherosclerosis: The value of physical exam. Am Surg 1996;62:861-4.
al-Zahrani HA, Rawas M, Maimani A, Gasab M, Aba al Khail BA. Screening for abdominal aortic aneurysm in the Jeddah area, Western Saudi Arabia. Cardiovasc Surg 1996;4:87-92.
Blanchard JF, Armenian HK, Friesen PP. Risk factors for abdominal aortic aneurysm: Results of a case-control study. Am J Epidemiol 2000;151:575-83.
Blann AD, Devine C, Amiral J, McCollum CN. Soluble adhesion molecules, endothelial markers and atherosclerosis risk factors in abdominal aortic aneurysm: A comparison with claudicants and healthy controls. Blood Coagul Fibrinolysis 1998;9:479-84.
Törnwall ME, Virtamo J, Haukka JK, Albanes D, Huttunen JK. Life-style factors and risk for abdominal aortic aneurysm in a cohort of Finnish male smokers. Epidemiology 2001;12:94-100.
Singh K, Bønaa KH, Jacobsen BK, Bjørk L, Solberg S. Prevalence of and risk factors for abdominal aortic aneurysms in a population-based study: The Tromsø study. Am J Epidemiol 2001;154:236-44.
Lederle FA, Johnson GR, Wilson SE, Chute EP, Hye RJ, Makaroun MS, et al.
The aneurysm detection and management study screening program: Validation cohort and final results. Aneurysm detection and management veterans affairs cooperative study investigators. Arch Intern Med 2000;160:1425-30.
Mortality results for randomised controlled trial of early elective surgery or ultrasonographic surveillance for small abdominal aortic aneurysms. The UK small aneurysm trial participants. Lancet 1998;352:1649-55.
Santilli JD, Santilli SM. Diagnosis and treatment of abdominal aortic aneurysms. Am Fam Physician 1997;56:1081-90.
[Table 1], [Table 2]