Gender based differences in Abdominal Aortic Aneurysm (AAA) rupture : A retrospective study

Introduction: Annually, 5% of sudden deaths are due to Abdominal Aortic Aneurysm (AAA) rupture. AAA ruptures have worse outcomes in females than males and occur at a smaller size in females. USPSTF recommends a one-time ultrasound screening for males aged 65-75 years who ever smoked. There is insufficient evidence to screen females aged 65-75 years who ever smoked in-spite of the available evidence. The objective of this study is to compare the characters, mortality and morbidity of ruptured AAAs in females and males. Methods: This is a retrospective review of 117 patients from two teaching institutions over a period of six years. A total of 39 parameters were compared between males and females including demographic characters, co-morbidities like hypertension, dyslipidemia, diabetes mellitus, cardiovascular diseases; previous history of AAA; medications, characters of aneurysm, type of surgery and its outcome; post-operative complications and long term survival. Results: The incidence of AAA rupture was higher in males (68%) than in females (32%). Females had a later age of death from AAA rupture. There was a significant difference in the size of AAA rupture between females (mean=7.4 cm) and males (mean=8.2 cm); p = 0.04. The probability to undergo surgery for ruptured AAA was significantly lower for females as compared to males (p=0.03). Females had higher overall mortality (p=0.001) and post-operative mortality after surgical repair (p=0.02) from AAA. Female gender was an independent predictor of higher length of ICU stay, incidence of postoperative complications, use of vasopressors and use of ventilator. Conclusion: Using a similar threshold of size of AAA for elective surgery for both males and females might not be appropriate. AAA screening might be warranted for high risk females owing to the higher morbidity and mortality.