Sex differences in Japanese patients with ruptured aortic aneurysms.

OBJECTIVE:This study aimed to assess the sex differences in clinical presentation and outcomes of Japanese patients with ruptured aortic aneurysm (rAA) using a large nationwide claims-based database in Japan. METHODS:We identified patients hospitalized in certified teaching hospitals in Japan with rAA between April 1, 2012, and March 31, 2015. Patients' characteristics and in-hospital outcomes were compared between men and women. The Barthel index was used for evaluating functional status at discharge by examining the ability to perform basic daily activities. RESULTS:Of 7086 eligible patients, 32.3% (2291/7086) were women. Women were older than men (81.9 years vs 76.1 years; P < .001), had higher prevalence of coma at admission (33.2% vs 25.2%; P < .001), and were less likely to undergo emergency operation including endovascular aneurysm repair (35.7% vs 51.1%; P < .001). The unadjusted mortality rate (62.5% vs 52.0%; P < .001) and Barthel index at discharge (78.7 vs 86.1; P < .001) were significantly worse in women than in men. However, multilevel mixed-effect logistic regression analyses showed that female sex itself was not an independent predictor for in-hospital death (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.78-1.04; P = .17). Older age, coma at admission, and vasopressor use were detected as independent predictors for in-hospital death. The same results were confirmed for each rupture site. Stratified analyses showed that older women (threshold, 80 years; OR, 0.81; 95% CI, 0.66-0.98; P = .028) and those who underwent emergency operation (OR, 0.75; 95% CI, 0.61-0.93; P = .009) showed significantly better outcomes than men. CONCLUSIONS:In a univariate analysis, female patients with rAA showed worse mortality than men because of their older age, more severe clinical presentation, and low emergency operation rate. However, after adjustment for covariates, female sex itself was not associated with increased mortality.