Table 1 Baseline characteristics of the patients between 30-day readmission and non-readmission groups
Variables | Total patients (n = 1270) | Groups | †P for Trend | |
|---|---|---|---|---|
Without readmission (n = 1084) | 30-day readmission (n = 186) | |||
Demographic | ||||
 Male gender (n, %) | 506 (39.8) | 439(40.5) | 67(36.0) | 0.250 |
 Age, × year (Mean, SD) | 74.69(9.55) | 73.79(9.46) | 79.92(8.35) | < 0.001 |
 Smoking (n, %) | 218 (17.2) | 191(17.6) | 27(14.5) | 0.300 |
 Alcohol (n, %) | 148(11.7) | 130 (12.0) | 18(9.7) | 0.364 |
Comorbidities | ||||
 Hypertension (n, %) | 636(50.1) | 519(47.9) | 117(62.9) | < 0.001 |
 Diabetes (n, %) | 291(22.9) | 230(21.2) | 61(32.8) | 0.01 |
 COPD (n, %) | 149(11.7) | 119(11.0) | 30(16.1) | 0.044 |
 Cardiovascular disease (n, %) | 390(30.7) | 319(29.4) | 71(38.2) | 0.017 |
 Stroke (n, %) | 330(26.0) | 252(23.2) | 78(41.9) | < 0.001 |
 Dementia(n, %) | 48(3.8) | 39(3.6) | 9(4.8) | 0.412 |
 Intracerebral hemorrhage (n, %) | 68(5.4) | 51(4.7) | 17(9.1) | 0.013 |
 Chronic liver disease (n, %) | 58(4.6) | 45(4.2) | 13(7.0) | 0.087 |
 Chronic kidney disease (n, %) | 64(5.0) | 48(4.4) | 16(8.6) | 0.016 |
Operation | ||||
 Fracture type | ||||
  Femoral neck fracture (n, %) | 679 (53.5) | 575(53.0) | 104(55.9) | 0.560 |
  Intertrochanteric fracture (n, %) | 517(40.7) | 443(40.9) | 74(39.8) | |
  Subtrochanteric fracture (n, %) | 74(5.8) | 66(6.1) | 8(4.3) | |
 Surgery type | ||||
  Total Hip Arthroplasty (n, %) | 161(12.7) | 139(12.8) | 22(11.8) | < 0.001 |
  Hemiarthroplasty (n, %) | 319(25.1) | 251(23.2) | 68(36.6) | |
  Intramedullary nail fixation (n, %) | 414(32.6) | 355(32.7) | 59(31.7) | |
  Internal fixation with steel plate (n, %) | 168(13.2) | 146(13.5) | 22(11.8) | |
  Internal fixation with hollow nails (n, %) | 208(16.4) | 193(17.8) | 15(8.1) | |
Intraoperative blood loss, × ml (Mean, SD) | 175.30(152.90) | 173.97(153.55) | 183.08(149.21) | 0.453 |
Transfusion (n, %) | 210(16.5) | 175(16.1) | 35(18.8) | 0.365 |
Postoperative ICU (n, %) | 63(5.0) | 53(4.9) | 10(5.4) | 0.777 |
Admission time | ||||
 < 6 h (n, %) | 672(52.9) | 577(53.2) | 95(51.1) | 0.087 |
 6–24 h (n, %) | 195(15.4) | 174(16.1) | 21(11.3) | |
  ≥ 24 h (n, %) | 403(31.7) | 333(30.7) | 70(37.6) | |
Bedridden time, × day (Mean, SD) | 5.90(4.03) | 5.85(4.07) | 6.18(3.80) | 0.299 |
Intraoperative time, × hour (Mean, SD) | 1.67(0.80) | 1.68(0.82) | 1.58(0.68) | 0.096 |
ASA classification | ||||
 III-IV (n, %) | 710(55.9) | 566(52.2) | 144(77.4) | < 0.001 |
 I-II (n, %) | 560(44.1) | 518(47.8) | 42(22.6) | |
Laboratory findings | ||||
 WBC count, × 10^9/L (Mean, SD) | 8.84(2.86) | 8.78(2.85) | 9.16(2.88) | 0.098 |
 HGB level, × g/L (Mean, SD) | 119.80(20.63) | 120.77(20.44) | 114.14(20.84) | 0.102 |
 Blood glucose, × mmol/L (Mean, SD) | 6.92(2.65) | 6.78(2.53) | 7.79(3.12) | < 0.001 |
 BUN, × mmol/L (Mean, SD) | 7.39(4.85) | 7.27(4.77) | 8.14(5.22) | 0.024 |
 Cr, × umol/L (Mean, SD) | 72.35(64.38) | 70.99(58.47) | 80.29(91.34) | 0.069 |
 D-Dimer, × mg/L (Mean, SD) | 4.89(5.04) | 4.82(5.01) | 5.28(5.22) | 0.241 |
Common complication | ||||
 DVT (n, %) | 164(12.9) | 130(12.0) | 34(18.3) | 0.018 |
 UTI (n, %) | 294(23.1) | 238(22.0) | 56(30.1) | 0.015 |
 Pneumonia (n, %) | 115(9.1) | 79(7.3) | 36(19.4) | < 0.001 |