By Dr Ananya Mandal, MD
Abdominal aorta aneurysm is more widely prevalent than the available numbers. This is because most of the cases are undetected and go unreported.
In the United Kingdom the prevalence of abdominal aorta aneurysm is estimated at 1.3-12.7%. Presence of symptoms of the aneurysm is noted in around 25 per 100,000 at age 50. This number is sharply increased to 78 per 100,000 in those over the age of 70.
In the United States, the incidence of abdominal aorta aneurysms is 2 to 4 percent in the adult population. It is seen that brothers of patients with abdominal aorta aneurysms are at a four to six times greater risk of the condition with a risk of 20 to 30 percent.
Incidence of new reported cases
The incidence of new reported cases of abdominal aorta aneurysm has been on the rise between the three decades (1970’s to 2000) in UK. This could be due to the advent of smokers and rise of dyslipidemia (high blood cholesterol) and obesity. These risk factors have led to atherosclerosis and hardening of the arterial walls leading to aneurysms.
Over the years, however, with the advent of effective cholesterol lowering medications and decline in smoking rates the numbers appear to be declining.
Abdominal aorta aneurysms may rupture or lead to dissection (a form of rupture) in a lower number of individuals. Aortic dissections are responsible for at least 15,000 deaths yearly. In 2000 in the United States aortic dissection due to abdominal aorta aneurysm was the 10th leading cause of death in white men 65 to 74 years of age. Rupture of the aneurysm occurs in 1 to 3 percent of men aged 65 or more, the mortality is 70 to 95 percent.
Incidence in males and females
The frequency varies strongly between males and females. The peak incidence is among males around 70 years of age. Over 60 years of age the rate of abdominal aortic aneurysm among males is 2 to 6 percent.
Abdominal aorta aneurysms and heritage
Some ethnic and races are naturally less susceptible to abdominal aorta aneurysms. These aneurysms for example are uncommon in individuals of African, Asian, and Hispanic heritage.
Abdominal aorta aneurysms and smoking
Smokers have a higher rate of abdominal aorta aneurysms than non smokers. They are 8 times more at risk actually compared to non-smokers. The risk reduces gradually after cessation of smoking.
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)