Table 4.
Risk factors for growth and rupture of small abdominal aortic aneurysm based on a previous individual patient data meta-analysis
| Risk factor | n | Growth | Rupture | |||
|---|---|---|---|---|---|---|
| n | Mean difference | P | HR | P | ||
| Age (per year) | 13 966 | 13 966 | −0.001 (0.006) | 0.82 | 1.04 (1.01, 1.07) | 0.004 |
| Female sex | 8472 | 8472 | 0.142 (0.150) | 0.34 | 3.76 (2.58, 5.47) | <0.001 |
| Body mass index (per kg/m2) | 3439 | 3439 | −0.008 (0.009) | 0.35 | 0.93 (0.88, 0.99) | 0.029 |
| Current smoking | 7486 | 7486 | 0.354 (0.065) | <0.001 | 2.02 (1.33, 3.06) | 0.001 |
| Diabetes | 5697 | 5697 | −0.505 (0.097) | <0.001 | 1.27 (0.45, 3.54) | 0.65 |
| Mean blood pressure (per 10 mmHg) | 5957 | 5957 | 0.013 (0.021) | 0.53 | 1.32 (1.11, 1.56) | 0.001 |
| Pulse pressure (per 10 mmHg) | 5957 | 5957 | −0.027 (0.014) | 0.06 | 1.11 (1.02, 1.22) | 0.019 |
| Cardiovascular disease | 6302 | 6302 | −0.105 | 0.23 | 1.32 (0.77, 2.27) | 0.32 |
The data presented are from an individual patient meta-analysis including 15 475 patients with small AAA attending surveillance programs in the UK, Australia, Norway, the USA, Sweden, and Denmark as previously reported.40 Data available varied for different risk factors; thus, the sample size for each risk factor has been shown (n). Shown are estimated mean difference (standard error of the mean) in AAA growth (mm/year) for each risk factor or hazard ratio (HR; 95% CI) for risk of aneurysm rupture as previously reported.40 Abdominal aortic aneurysm growth estimates were adjusted for the other risk factors shown in the table and initial AAA diameter, while HRs were adjusted for current AAA diameter only.