Week-One Anaemia was Associated with Increased One-Year Mortality in Critically Ill Surgical Patients

Table 2

Cox proportional hazards regression for one-year mortality among 7,623 critically ill surgical patients.

Characteristics	Univariable		Multivariable
	HR (95% C.I.)	p value	HR (95% C.I.)	p value
Basic characteristics
Age, per 1 year increment	1.026 (1.023–1.029)	<0.001	1.007 (1.004–1.010)	<0.001
Male gender	1.246 (1.131–1.372)	<0.001	1.144 (1.037–1.262)	0.007
Body mass index, per 1 increment	0.946 (0.936–0.957)	<0.001	0.964 (0.953–0.974)	<0.001
Charlson comorbidity index	1.308 (1.274–1.343)	<0.001	1.168 (1.134–1.202)	<0.001
Severity and managements
APACHE II score, per 1 increment	1.130 (1.121–1.139)	<0.001	1.058 (1.049–1.068)	<0.001
Presence of shock	2.533 (2.314–2.773)	<0.001	1.508 (1.361–1.671)	<0.001
Surgical divisions
Cardiovascular surgery	0.366 (0.309–0.435)	<0.001	0.266 (0.221–0.320)	<0.001
Neurosurgery	0.446 (0.398–0.499)	<0.001	0.612 (0.539–0.697)	<0.001
Major abdomen surgery	1.986 (1.722–2.290)	<0.001	0.712 (0.612–0.827)	<0.001
Receiving RBC transfusion	2.452 (2.227–2.700)	<0.001	1.012 (0.894–1.146)	0.851
Receiving mechanical ventilation	1.708 (1.531–1.905)	<0.001	1.093 (0.970–1.231)	0.146
Receiving renal replacement therapy	4.050 (3.574–4.590)	<0.001	1.422 (1.235–1.637)	<0.001
Fluid overload, day 1–3, per 1 litre increment	1.166 (1.149–1.183)	<0.001	1.036 (1.019–1.054)	<0.001
Positive microbiological culture	3.054 (2.787–3.346)	<0.001	1.298 (1.165–1.446)	<0.001
Laboratory data
Platelet (per 10^3/μL increment)	0.995 (0.994–0.995)	<0.001	0.998 (0.998–0.999)	<0.001
Albumin (per 1 mg/dL increment)	0.434 (0.407–0.464)	<0.001	0.766 (0.709–0.827)	<0.001
Haemoglobin <10 g/dL	2.880 (2.631–3.153)	<0.001	1.170 (1.045–1.310)	0.007

PSM, propensity score matching; IPTW, inverse probability of treatment weighting; CBPS, covariate balancing propensity score; HR, hazard ratio; CI, confidence interval.