Changing epidemiology of abdominal aortic aneurysms in England and Wales: older and more benign?

Abstract

Background: Recent studies from Australia, New Zealand, and Sweden have reported declines in abdominal aortic aneurysm (AAA) incidence, prevalence, and mortality. This finding may have important implications for screening programs. This study determined trends in AAA incidence and mortality in England and Wales.

Methods and results: Cause-specific mortality data for England and Wales were obtained from UK Office for National Statistics, and hospital admissions and procedures data for England were obtained from Hospital Episode Statistics from 2001 to 2009. Poisson regression models were constructed to estimate the relative change over time. Age-standardized rates for AAA mortality in England and Wales fell significantly by 35.7% from 2001 to 2009, which was largely due to a 35.3% drop in age-standardized ruptured AAA deaths. During the same period, ruptured AAA admissions and emergency AAA repairs in England declined by 29.3% and 35.5%, respectively. In contrast, nonruptured AAA admissions remained static, and nonemergency AAA repairs increased by 17.2%. The average ages for hospital admissions for nonruptured AAAs and ruptured AAAs increased by 0.19 years of age per annum (P<0.001) and 0.09 years of age per annum (P<0.001), respectively. Nonruptured AAA admissions increased by 21.4% in age band 75 years or more but declined by 11.7% in ages <75 years.

Conclusions: AAA mortality, ruptured AAA admission, and emergency AAA repair have declined in England and Wales. However, nonruptured AAA admission has remained steady, with an increasing rate in older population offsetting a decreasing rate in younger population. This suggests a shift in AAA presentation to the older population. Present screening strategies may need reassessment to include consideration for increasing the age at which to screen men for AAAs.