New research published on bmj.com has more bad news for women smokers. Compared to women who have quit smoking, women smokers are four times more likely to have an abdominal aortic aneurysm repair or rupture. Further, women smokers are eight times more likely to have the condition than women who have never smoked.

Abdominal aortic aneurysms are characterized by a localized swelling or ballooning of the wall of the largest artery in the body. Although they occur more commonly in men, these aneurysms have been more fatal to women. Abdominal aortic aneurysms rupture at smaller diameters in women, and the rate of intervention is lower. Thus, the number of deaths after intervention for females may be higher than males. Every year, 15,000 deaths in the US are due to abdominal aortic aneurysms – 40% of which are women.

Men have historically been the focus of research studies related to abdominal aortic aneurysms, and most studies have not included enough women to confidently assess the risk factors in women. Improvements in diagnoses and outcomes for women may arise if researchers can better understand abdominal aortic aneurysm risk factors that are particular to women.

To fill in this knowledge gap, Professor Frank Lederle (VA Medical Center, Minneapolis, MN) and colleagues studied 161,808 postmenopausal women at 40 clinical centers in the US. The researchers followed the women – all part of the Women’s Health Initiative – for about 7.8 years to gain a better understanding of the risk factors associated with the rupture and repair of abdominal aortic aneurysms. Additionally, Lederle and colleagues were able to analyze the relationship between hormone replacement therapy (HRT) and abdominal aortic aneurysms in women.

During the study, 184 women reported abdominal aneurysm repairs or ruptures, and these events were strongly correlated with age and smoking. The likelihood of having an abdominal aortic aneurysm was positively associated with smoking in the past, smoking in the present, and the amount smoked.

Although previous studies have found that estrogen therapy alone may increase the risk of abdominal aortic aneurysm, Lederle and colleagues found that HRT provided protection from the condition. Having diabetes was also linked to a reduced risk of aneurysm events. Other traits found to be positively associated with abdominal aortic aneurysm events were increasing height, hypertension, high cholesterol, and coronary and peripheral artery disease.

“Further studies will be needed to clarify the effect of hormone therapy on aortic aneurysm,” conclude the researchers.

Professor Janet Powell (Imperial College London) and Professor Paul Norman (University of Western Australia) write in an accompanying editorial that it is important for women to be educated about smoking, and efforts to convince them to quit smoking should remain a public health priority.

They conclude: “In the United States screening is in place for women with a strong family history of abdominal aortic aneurysm, but if the incidence of this disorder in women continues to rise, population screening for women who have smoked or continue to smoke might need to be considered.”

Abdominal aortic aneurysm events in the women’s health initiative: cohort study
Frank A Lederle, Joseph C Larson, Karen L Margolis, Matthew A Allison, Matthew S Freiberg, Barbara B Cochrane, William F Graettinger, J David Curb
BMJ (2008). 337:a1724
doi:10.1136/bmj.a1724
Click Here to View Journal Web Site

Written by: Peter M Crosta