Fifty-one studies were included in the review.
Four RCTs (137,214 participants) of fair-to-good quality found that invitation for screening in men aged 65 years or older significantly reduced deaths due to aneurysm and the number of emergent surgeries up to 15 years, and aneurysm rupture rates up to 11 years, but did not significantly change all-cause mortality.
One fair-quality population-based screening RCT (9,342 participants) examined AAA screening in women, showing that screening had no benefit on all-cause and aneurysm-related mortality. One RCT showed that screening only high-risk people reduced the number of patients screened, but prevented only half the aneurysm deaths.
Based on the four fair-to-good quality RCTs, invitation for screening was associated with some harm, such as more surgery and more elective surgery, but fewer emergency operations and deaths up to 30 days after surgery, within 10 to 15 years of follow-up. Five small observational studies reported conflicting results on the influence of screening on quality of life and anxiety or depression measures.
An analysis of two good-quality RCTs (2,226 participants) demonstrated that early open surgery, compared with surveillance, for small aneurysms (4cm to 5cm) significantly reduced the five-year rupture rate, but did not alter aneurysm or all-cause mortality within up to 12 years of follow-up. Meta-analysis of two underpowered fair-quality RCTs (1,088 participants) of early endovascular repair, compared with surveillance, for small aneurysms found that endovascular repair did not reduce all-cause and AAA-related mortality, nor AAA rupture.
One good-quality trial found no significant effect on mortality and AAA growth rate after two years of beta-blocker use and three good-to-fair quality trials found no significant effects on mortality with different antibiotics, but showed mixed results for AAA growth rates.
Participants with small aneurysms, randomised to early open surgery or early endovascular repair, had an increased risk of surgery compared with those undergoing surveillance. Endovascular repair complications reported in the studies (2,440 participants) included systemic complications (15%), endoleaks (10%), and re-intervention (4%), but there was no difference in operative mortality. One fair-quality RCT (339 participants) suggested a higher quality of life with early endovascular surgery, compared with surveillance, in the first six months, but this did not persist at three-year follow-up.
Other subgroup and sensitivity analysis results were reported.