Descriptive statistics for treated aneurysm discharges from national inpatient sample, 1998–2007
| Factors | Ruptured (n=20 134) | Unruptured (n=14 765) | p Value |
| Age (years) | |||
| Mean±SD | 53.3±13.9 | 53.0±14.0 | 0.02 |
| Median | 53.0 | 54.0 | |
| Sex | |||
| Female | 13 839 (68.7) | 10 665 (72.2) | <0.001 |
| Male | 6259 (31.1) | 4005 (27.1) | |
| Race | |||
| White | 9073 (45.1) | 7658 (51.9) | <0.001 |
| Black | 2297 (11.4) | 1011 (6.8) | |
| Other (Hispanic, Asian or Native American) | 2243 (11.1) | 1129 (7.6) | |
| Unknown | 6521 (32.4) | 4967 (33.6) | |
| Income quartile (%) | |||
| <25 000 | 3626 (18.0) | 2511 (17.0) | 0.006 |
| 25 000–34 999 | 5002 (24.8) | 3687 (25.0) | |
| 35 000–44 999 | 5110 (25.4) | 3979 (26.9) | |
| ≥45 000 | 5732 (28.5) | 4234 (28.7) | |
| Healthcare coverage | |||
| Private insurance | 10 412 (51.7) | 8504 (57.6) | <0.001 |
| Public (Medicare or Medicaid) | 6923 (34.4) | 5225 (35.4) | |
| Self-pay | 1797 (8.9) | 431 (2.9) | |
| Charlson comorbidity score | |||
| Mean±SD | 0.47±0.73 | 0.39±0.65 | <0.001 |
| Admission source | |||
| Emergency room | 9695 (48.2) | 1020 (6.9) | <0.001 |
| Hospital/facility transfer | 6048 (30.0) | 690 (4.7) | |
| Elective | 3786 (18.8) | 12 622 (85.5) | |
| Treatment method | |||
| Clipping | 14 514 (72.1) | 7597 (51.5) | <0.001 |
| Coiling | 5620 (27.9) | 7168 (48.5) | |
| Hospital location | |||
| Northeast | 3326 (16.5) | 2595 (17.6) | <0.001 |
| Midwest | 4303 (21.4) | 3523 (23.9) | |
| South | 7976 (39.6) | 5686 (38.5) | |
| West | 4529 (22.5) | 2961 (20.1) | |
| Hospital size | |||
| Small | 970 (4.8) | 879 (6.0) | <0.001 |
| Medium | 3019 (15.0) | 1988 (13.5) | |
| Large | 16 131 (80.1) | 11 894 (80.6) | |
| Hospital type | |||
| Non-teaching | 3810 (18.9) | 1902 (12.9) | <0.001 |
| Teaching | 16 310 (81.0) | 12 859 (87.1) | |