TABLE 3.
Preoperative Characteristics of Patients Who Underwent Isolated Surgical Mitral Valve Replacement at Safety-Net vs Non–Safety-Net Hospitals
| Unmatched (n = 31 475) | Matched (n = 6350) | |||||
|---|---|---|---|---|---|---|
| Variable | Safety-Net Hospitals (n = 5516) |
Non–Safety-Net Hospitals (n = 25 959) |
P Value |
Safety-Net Hospitals (n = 3175) |
Non–Safety-Net Hospitals (n = 3175) |
SMD |
| Age, y | 64 (55-73) | 67 (58-75) | <.001 | 64 (55-73) | 64 (55-73) | −0.005 |
| Male | 2201 (39.9) | 10 579 (40.8) | .2 | 1893 (59.6) | 1932 (60.9) | −0.025 |
| Elixhauser score | 14 (6-22) | 14 (6-22) | .2 | 14 (6-22) | 14 (6-22) | …b |
| Anemia | 1144 (20.7) | 4410 (17.0) | <.001 | 651 (20.5) | 633 (19.9) | 0.014 |
| Chronic kidney disease | 1031 (18.7) | 5342 (20.6) | .002 | 596 (18.8) | 614 (19.4) | 0.005 |
| COPD | 1467 (26.6) | 7175 (27.6) | .1 | 595 (18.7) | 589 (18.6) | −0.021 |
| Coagulopathy | 1942 (35.2) | 9646 (37.2) | .006 | 1121 (35.3) | 1116 (35.2) | 0.003 |
| Congestive heart failure | 3476 (63.0) | 16 111 (62.1) | .2 | 2005 (63.2) | 1989 (62.7) | 0.010 |
| Diabetes mellitus | 642 (11.6) | 2232 (8.6) | < .001 | 372 (11.7) | 363 (11.4) | 0.009 |
| Drug abuse | 1638 (29.7) | 7474 (28.8) | .2 | 943 (29.7) | 957 (30.1) | −0.009 |
| Hypertension | 215 (3.9) | 438 (1.7) | <.001 | 95 (3.0) | 90 (2.9) | 0.009 |
| Obesity | 1116 (20.2) | 5823 (22.4) | <.001 | 626 (19.7) | 619 (19.5) | 0.005 |
| Peripheral arterial disease | 443 (8.0) | 2450 (9.4) | .001 | 252 (7.9) | 248 (7.8) | 0.004 |
| Household incomea | <.001 | |||||
| Quartile 1 | 1795 (33.1) | 6680 (26.1) | 979 (31.4) | 971 (31.1) | 0.006 | |
| Quartile 2 | 1454 (26.8) | 7196 (28.2) | 836 (26.8) | 832 (26.7) | 0.003 | |
| Quartile 3 | 1269 (23.4) | 6447 (25.2) | 757 (24.3) | 778 (24.9) | −0.015 | |
| Quartile 4 | 904 (16.7) | 5241 (20.5) | 548 (17.6) | 539 (17.3) | 0.007 | |
| Bioprosthetic valve | 3531 (64.0) | 18 353 (70.7) | <.001 | 2035 (64.1) | 2015 (63.5) | −0.014 |
| Mechanical valve | 1981 (35.9) | 7615 (29.3) | <.001 | 1139 (35.9) | 1160 (35.5) | 0.013 |
| Nonelective | 1839 (33.4) | 7284 (28.1) | < .001 | 1028 (32.4) | 1053 (33.2) | 0.504 |
a
Indexed to patient’s zip code
b
Cohorts matched by each individual Elixhauser comorbidity and not composite score. Values are median (interquartile range) or n (%). COPD, chronic obstructive pulmonary disease; SMD, standardized mean difference.