Table 3.

Multivariate Analysis of Independent Risk Factors for POH After Elective Cardiac Surgery

Characteristics	Coefficient	SE	OR (95% CI)	P value
Female sex	1.071	0.076	2.920 (2.518–3.386)	<0.001
Age, y	−0.056	0.003	0.945 (0.941–0.950)	<0.001
Smoking history	1.004	0.080	2.729 (2.332–3.195)	<0.001
Chronic headache history	1.282	0.092	3.605 (3.011–4.317)	<0.001
Hypertension	1.019	0.071	2.771 (2.410–3.186)	<0.001
LVEF, %	−0.089	0.004	0.915 (0.908–0.922)	<0.001
Cardiopulmonary bypass time, min	0.018	0.001	1.019 (1.017–1.020)	<0.001
Intraoperative transfusion of RBCs, units	0.322	0.015	1.379 (1.340–1.420)	<0.001

LVEF indicates left ventricular ejection fraction; OR, odds ratio; POH, postoperative headache; and RBC, red blood cell.