Table 3 Postoperative anemia of THA: univariate and multivariate analysis of possible risk factors in the validation cohort

Age (years)

1.019 (1.002–1.037)

0.029

1.011 (0.979–1.043)

0.512

BMI (kg/m²)

0.878 (0.810–0.952)

0.002

0.899 (0.797–1.014)

0.082

Sex

 Male

1

 Female

0.833 (0.529–1.669)

0.833

Reasons of operation

 FNF

1

 ONFN

0.731 (0.433–1.232)

0.239

 OAH

0.735 (0.396–1.366)

0.331

 Operation time (min)

1.024 (1.015–1.033)

 < 0.001

1.032 (1.018–1.046)

 < 0.001

 Intraoperative blood loss (mL)

1.006 (1.004–1.009)

 < 0.001

1.004 (1.001–1.007)

0.014

Type of anesthesia

 GA

1

1

 CSEA

2.212 (1.396–3.505)

0.001

2.066 (1.018–4.194)

0.065

Smoking

 No

1

 Yes

1.598 (0.803–3.181)

0.182

Drinking

 No

1

 Yes

1.495 (0.732–3.054)

0.269

Hypertension

 No

1

1

 Yes

2.008 (1.266–3.185)

0.003

1.203 (0.615–2.352)

0.589

Diabetes

 No

1

 Yes

1.480 (0.824–2.656)

0.189

Cardiovascular disease

 No

1

 Yes

0.921 (0.440–1.927)

0.828

Cerebrovascular disease

 No

1

1

 Yes

2.661 (1.362–5.198)

0.004

1.748 (0.615–2.352)

0.232

Osteoporosis

 No

1

1

 Yes

2.252 (1.415–3.582)

0.001

2.117 (1.112–4.030)

0.022

TP (g/L)

0.981 (0.951–1.013)

0.242

ALB (g/L)

0.932 (0.887–0.979)

0.005

1.066 (0.983–1.156)

0.125

GLB (g/L)

1.022 (0.979–1.066)

0.325

SAA (mg/L)

1.006 (1.004–1.009)

 < 0.001

1.004 (1.000–1.007)

0.044

IRON (μmol/L)

0.969 (0.942–0.997)

0.027

0.986 (0.953–1.021)

0.428

TIBC (μmol/L)

1.007 (0.985–1.029)

0.559

CRP (mg/L)

1.003 (0.997–1.009)

0.317

RBC (1,012/L)

0.251 (0.163–0.386)

 < 0.001

0.341 (0.098–1.190)

0.092

HB (g/L)

0.944 (0.929–0.959)

 < 0.001

0.980 (0.917–1.048)

0.006

HCT (%)

0.832 (0.789–0.877)

 < 0.001

0.947 (0.792–1.133)

0.553

MCV (fL)

0.989 (0.957–1.022)

0.512

MCH (pg)

0.955 (0.881–1.036)

0.272

MCHC (g/L)

0.973 (0.954–0.993)

0.007

0.954 (0.917–0.993)

0.051