More patients are treated for nonruptured abdominal aortic aneurysms, but the proportion of women remains unchanged

Abstract

Background: Large variations in the intervention rates for ruptured and nonruptured abdominal aortic aneurysm (AAA) over time have been reported, both decreasing and increasing numbers. Women have been reported to constitute an increasing proportion of patients treated for several manifestations of cardiovascular disease; whether a similar trend is true for AAA is not well understood. This study investigated recent temporal trends in a complete national register regarding the number and type of procedure performed for AAA, and outcome, with special emphasis on gender differences.

Methods: Data for all individuals treated for nonruptured or ruptured AAA in Sweden (1990 to 2005) were obtained from the Swedish National Board of Health and Welfare (NBHW). A total of 14369 individuals were identified; 2327 (16%) were women. Date and type of intervention, date and cause of death, age, and sex were included in the statistical model.

Results: There was a relative annual increase in interventions for nonruptured AAA; 4% for women (P < .0001) and 2% for men (P < .0001). No significant trends were observed for interventions for rupture during the observation period. No significant increase in the proportion of women was recorded for nonrupture (17%) or rupture (15%). Women had higher crude 30-day mortality rate than men after treatment for both nonruptured (5.7% vs 4.9%) and ruptured (41.9% vs 36.8%) AAA. In a logistic regression model, survival improved over time after intervention for nonrupture (P < .0001) and rupture (P < .0001). Increasing age (P < .0001 for both nonrupture and rupture) but not sex (P = .49 for non rupture and P = .42 for rupture) had a negative influence on mortality.

Conclusion: Interventions for nonruptured but not for ruptured AAA increased over time, with an expected rapid increase of endovascular repair in the nonruptured group. The unchanged fraction of women over time possibly reflects the true distribution of AAA between the sexes. The outcome after treatment for both nonruptured and ruptured AAA improved, as anticipated, over time. No increase in mortality among women was recorded after adjustment for age.