The changing epidemiology of abdominal aortic aneurysms in Europe

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Throughout the 20th century the impact of abdominal aortic aneurysms increased with well documented escalations in its incidence and associated mortality. Contemporary evidence from the UK and many other developed countries has, however, confirmed a steep decline in mortality from abdominal aortic aneurysms.

It is likely that the prevalence of abdominal aortic aneurysms is falling secondary to cardiovascular risk factor modification and that the reduction in aneurysm mortality reflects this change. This view is supported by comparing findings from the randomised controlled trials of population-based aneurysm screening—which demonstrated abdominal aortic aneurysm prevalence of 5–7.6%—with more contemporary data, for example the UK NHS abdominal aortic aneurysm screening programme report from 2015 which revealed a current prevalence of 1.19%.

Utilising the World Health Organization (WHO) mortality database we have analysed abdominal aortic aneurysm-related mortality (2000–2014) in 23 eligible countries and its relationship to cigarette smoking. All mortality data was converted into deaths per 100,000 people and adjusted to the 2013 European Standard Population. Associations with cigarette smoking (1970–2013) were analysed using linear regression.

There are significant differences in age-standardised abdominal aortic aneurysm mortality trends across Europe, and similarly to the findings of our previous study (The Aneurysm Global Epidemiology Study) most of Europe is seeing reductions in the number of patients dying from abdominal aortic aneurysms. The UK had the steepest reduction in aneurysm mortality, though it did also have the highest standardised mortality at the earliest time point of the study (14.8) declining to 7.8 in 2013, and still remains high compared to much of Europe. Aneurysm mortality has fallen in much of Western Europe, for example in Germany (4.3 to 2.8) and The Netherlands (11.7 to 5.1). However, in Eastern Europe a different picture is emerging, with aneurysm mortality increasing, for example in Croatia (3 to 5) and Hungary (2.8 to 4.5). This appears to mirror geographical differences in the cigarette smoking population across Europe, for example in Russia (33%) or Croatia (31%) compared to Iceland (13%) or the UK (20%), as reported by the 2015 WHO report on the global tobacco epidemic.

Several studies have demonstrated a dose-dependent relationship between the risk of abdominal aortic aneurysm in smokers compared with non-smokers and tobacco smoking has well-established links with aneurysm expansion and rupture. Therefore it is not surprising that aneurysm mortality appears to mirror changes in the cigarette smoking population. Analysis of the mortality data with trends in cigarette smoking throughout Europe demonstrates a positive linear relationship (R2=0.6) suggesting that those countries with the largest reductions in cigarette exposure are also seeing the largest reductions in aneurysm mortality. This suggests that in Europe, public health measures to reduce rates of smoking could further reduce the risks associated with abdominal aortic aneurysm, likely through a reduction in prevalence.

Globally this could be achieved by full implementation of the six components of MPOWER—Monitoring of tobacco use and prevention policies; protection of people from tobacco smoke; offering help to quit tobacco use; warning about the dangers of tobacco; enforcing bans on advertising; and raising taxes on tobacco. These components remain fundamental to the WHO Framework Convention on Tobacco Control and highlight the practically achievable steps in a vascular clinic, namely offering patients help to quit tobacco and warning patients about the dangers of tobacco use.

David Sidloff, University of Leicester, Leicester, UK