Table 1.
Demographics of patients undergoing total hip arthroplasty. Values are frequency (%) unless otherwise stated
| Confounder | Smoker | Non-smoker | Ex-smoker |
|---|---|---|---|
| Total | 7,543 (12) | 34,271 (56) | 18,998 (31) |
| Male | 3,059 (41) | 11,343 (33) | 9,343 (49) |
| Female | 4,484 (59) | 22,928 (67) | 9,655 (51) |
| Age, mean (SD) | 63 (12) | 70 (11) | 70 (10) |
| BMI | |||
| Underweight | 228 (3.7) | 526 (1.8) | 227 (1.4) |
| Normal | 2,118 (34) | 8,692 (30) | 3,913 (23) |
| Overweight | 2,217 (36) | 11,771 (40) | 6,866 (41) |
| Obese class I | 1,140 (19) | 5,852 (20) | 4,015 (24) |
| Obese class II | 365 (5.9) | 1,849 (6.3) | 1,356 (8.1) |
| Obese class III | 110 (1.8) | 607 (2.1) | 392 (2.3) |
| Missing | 1,365 ( | 4,974 ( | 2,229 ( |
| Charlson score 1 year a | |||
| 0 | 6,962 (92) | 31,437 (92) | 16,874 (89) |
| 1 | 325 (4.3) | 1,398 (4.1) | 1,052 (5.5) |
| 2 | 206 (2.7) | 1,148 (3.3) | 803 (4.2) |
| ≥ 3 | 50 (0.7) | 288 (0.8) | 269 (1.4) |
| Deprivation Index rank | |||
| 1 | 416 (9.6) | 3,446 (17) | 1,574 (14) |
| 2 | 418 (9.7) | 2,862 (14) | 1,453 (13) |
| 3 | 436 (10) | 2,697 (13) | 1,444 (13) |
| 4 | 469 (11) | 2,552 (12) | 1,387 (12) |
| 5 | 488 (11) | 2,590 (13) | 1,480 (13) |
| 6 | 418 (9.7) | 1,908 (9.2) | 1,092 (9.4) |
| 7 | 389 (9.0) | 1,635 (7.9) | 995 (8.6) |
| 8 | 402 (9.3) | 1,283 (6.2) | 882 (7.6) |
| 9 | 426 (9.9) | 959 (4.6) | 675 (5.8) |
| 10 | 461 (11) | 756 (3.7) | 599 (5.2) |
| Missing | 3,220 ( | 13,583 ( | 7,417 ( |
| Alcohol consumption | |||
| Yes | 4,691 (80) | 21,151 (78) | 13,029 (84) |
| No | 898 (15) | 5,628 (21) | 1,854 (12) |
| Ex | 243 (4.2) | 530 (1.9) | 555 (3.6) |
| Missing | 1,711 ( | 6,962 ( | 3,560 ( |
| Year of surgery | |||
| 1995–2000 | 738 (9.8) | 2,980 (8.7) | 736 (3.9) |
| 2001–2010 | 4,291 (57) | 18,864 (55) | 10,710 (56) |
| 2011–2016 | 2,514 (33) | 12,427 (36) | 7,552 (40) |
| Preoperative Oxford Hip Score | |||
| median (IQR) | 16 (11–21) | 18 (13–24) | 18 (12–24) |
a
Charlson index score based on comorbidities 1 year prior to index date.