Table 1 Baseline characteristics of the 1444 participants

N

349

151

534

410

Age (years)

75.17 (8.88)

75.85 (8.75)

77.70 (8.62)

79.98 (8.08)

Sex (n, %)

 Male

75 (21.49%)

48 (31.79%)

144 (26.97%)

122 (29.76%)

 Female

274 (78.51%)

103 (68.21%)

390 (73.03%)

288 (70.24%)

BMI (kg/m²)

22.12 (3.14)

22.41 (3.13)

22.09 (3.38)

21.69 (3.21)

Classification of fracture (n, %)

 Intertrochanteric fracture

255 (73.07%)

100 (66.23%)

339 (63.48%)

231 (56.34%)

 Femoral neck fracture

94 (26.93%)

51 (33.77%)

195 (36.52%)

179 (43.66%)

Time from fracture to surgery (hours)

76.00 (50.00–141.00)

72.00 (47.00–127.50)

76.50 (49.00–137.75)

90.00 (60.00–144.75)

Comorbidity

234 (67.05%)

106 (70.20%)

392 (73.41%)

310 (75.61%)

Smoking status (n, %)

14 (4.01%)

8 (5.30%)

23 (4.31%)

22 (5.37%)

COPD (n, %)

4 (1.15%)

6 (3.97%)

12 (2.25%)

7 (1.71%)

Asthma (n, %)

6 (1.72%)

0 (0.00%)

6 (1.12%)

9 (2.20%)

Hypertension (n, %)

142 (40.69%)

67 (44.37%)

264 (49.44%)

221 (53.90%)

Coronary heart disease (n, %)

36 (10.32%)

13 (8.61%)

72 (13.48%)

69 (16.83%)

Atrial fibrillation (n, %)

12 (3.44%)

9 (5.96%)

24 (4.49%)

25 (6.10%)

Stroke (n, %)

54 (15.47%)

28 (18.54%)

100 (18.73%)

75 (18.29%)

Parkinson’s disease (n, %)

8 (2.29%)

4 (2.65%)

16 (3.00%)

5 (1.22%)

Diabetes mellitus (n, %)

80 (22.92%)

36 (23.84%)

125 (23.41%)

85 (20.73%)

WBC count (× 10^9/L)

9.04 (2.96)

9.87 (3.35)

9.11 (2.93)

9.19 (3.11)

Lymphocyte count (× 10^9/L)

1.26 (0.50)

1.29 (0.59)

1.32 (0.65)

1.28 (0.59)

Neutrophil count (× 10^9/L)

7.07 (2.96)

7.95 (3.34)

7.12 (2.76)

7.33 (4.40)

Monocyte count (× 10^9/L)

0.55 (0.41–0.72)

0.59 (0.45–0.75)

0.53 (0.40–0.70)

0.53 (0.39–0.71)

MLR

0.47 (0.33–0.66)

0.49 (0.37–0.66)

0.44 (0.31–0.61)

0.44 (0.30–0.63)

NLR

5.48 (3.63–8.27)

6.10 (4.09–9.32)

5.27 (3.68–7.96)

5.59 (3.91–8.20)

Platelet count (× 10^9/L)

211.27 (74.57)

206.82 (80.06)

200.96 (64.76)

215.03 (89.14)

Hemoglobin (g/L)

121.00 (16.40)

120.82 (16.69)

118.38 (18.03)

108.76 (20.04)

Albumin (g/L)

39.01 (4.06)

38.69 (4.04)

38.07 (4.11)

36.99 (5.05)

Globulin (g/L)

28.55 (5.27)

30.12 (16.65)

27.86 (4.55)

28.62 (5.62)

AGR

1.41 (0.30)

1.36 (0.24)

1.40 (0.28)

1.33 (0.29)

Serum creatinine (umol/L)

60.00 (48.40–73.10)

65.30 (54.10–76.95)

66.00 (53.85–82.55)

67.45 (55.05–88.27)

Blood urea nitrogen (mmol/L)

4.50 (2.84–6.30)

4.90 (3.33–6.42)

5.10 (3.27–6.70)

5.30 (3.61–7.40)

Operation method (n, %)

 Internal fixation

128 (36.68%)

71 (47.02%)

221 (41.39%)

179 (43.66%)

 Hip replacement

221 (63.32%)

80 (52.98%)

313 (58.61%)

231 (56.34%)

Anesthesia method (n, %)

 General anesthesia

266 (76.22%)

111 (73.51%)

416 (77.90%)

307 (74.88%)

 Non-general anesthesia

83 (23.78%)

40 (26.49%)

118 (22.10%)

103 (25.12%)

ASA classification (n, %)

 ≤ 2

186 (53.30%)

79 (52.32%)

231 (43.26%)

128 (31.22%)

 ≥ 3

163 (46.70%)

72 (47.68%)

303 (56.74%)

282 (68.78%)

Intraoperative blood loss (mL)

200.00 (100.00–300.00)

200.00 (100.00–300.00)

200.00 (100.00–300.00)

200.00 (100.00–300.00)

Operation duration (min)

84.22 (31.99)

91.04 (32.70)

85.25 (35.76)

83.00 (39.70)

In-hospital death (n, %)

0 (0.00%)

1 (0.66%)

3 (0.56%)

1 (0.24%)

ICU admission (n, %)

6 (1.72%)

1 (0.66%)

13 (2.43%)

11 (2.68%)

POP (n, %)

14 (4.01%)

4 (2.65%)

31 (5.81%)

42 (10.24%)

Length of hospital stay (days)

10.00 (8.00–14.00)

10.00 (7.00–13.00)

10.00 (8.00–15.00)

11.00 (8.00–17.00)