BACKGROUND The purpose of this study is to quantify age- and gender-specific mortality risks for patients hospitalized for ruptured abdominal aortic aneurysm (rAAA). METHODS The mortality risks for 28-day, 1-year, and 5-year were derived from a retrospective nation-wide cohort study of patients who were first hospitalized for rAAA in 1997 or 2000, formed through linkage of the Hospital Discharge Register with the Dutch population register. The Hospital Discharge Register contains a record for each hospital admission, giving information about patient demographics and diagnosis. The population register contains information on patient demographics and the mortality status of all registered persons in The Netherlands. Relations between gender and mortality within specific age groups were assessed with chi-square tests. Associations between age, gender, comorbidities, and mortality were studied in multivariate analysis with Cox regression. RESULTS A total of 1,463 patients hospitalized for rAAA were identified (86% males). Mean age was higher in women than in men (79 vs. 72 years; 95% CI of difference: 5.0-7.4). Mortality risks at 28-day, 1-year, and 5-year increased significantly with age (28-day: from 36 to 91% in men and 59 to 92% in women; 5-year: from 51 to 97% in men and 79 to 96% in women). In patients aged <80 years, mortality risks were significantly higher in women than in men. Age (HR: 1.04; 95% CI: 1.03-1.05), previous hospitalization for congestive heart failure (HR: 1.55; 95% CI: 1.06-2.26), and cerebrovascular disease (HR: 1.60; 95% CI: 1.16-2.21) were significant predictors of short- and long-term mortality. CONCLUSIONS Mortality risks after hospitalization for rAAA clearly increase by age and are higher in women than in men in patients aged <80 years. Because of the major effect of age and gender, future studies should consider reporting absolute mortality risks stratified by age and gender, instead of simply presenting overall mortality risks.