ABSTRACT
Prevalence (the number of existing cases) of AAAs is age-dependent; in adult autopsy studies prevalence ranges from 1-6%, but in a recent U.K. study, AAAs were present in 2% of men aged 65-75 years, and 9% for those older than 75.5 In an autopsy study from the Massachusetts General Hospital, AAAs were found in 2% of 24,000 consecutive post mortem examinations.6 Similar studies in unselected popu lations, using postmortem examinations, US studies, and C T scans have reported a similar prevalence of about 2-3%.7'9 Johnson and associates found more aneurysms in white men (4.2%) than in white women, black men, and black women (all about 1.5%)8 AAAs occur considerably more ffequendy than thoracic aneurysms. Lilienfield and colleagues reported that the ratio o f abdominal: thoracic aneurysms was 7:1 in men and 3:1 in women.10 The number of new cases o f AAAs among residents o f Rochester, Minnesota, during 1976-1980 was about seven times higher than the incidence of racic aneurysms.11 Repair of arterial aneurysms constitutes about 13% of the vascular experience of general surgical residents, and probably accounts for an even higher percentage o f operations performed by vascular surgeons in practice.12
