TABLE IV.

Multivariate Analysis of HLA Alloimmunization in SCD

Variable	Odds ratio	Wald 95% CI	P-value
RBC antibodies	3.61	(1.05–12.3)	0.041
Age ≥13	3.08	(0.69–13.8)	0.14
Lifetime number of RBC unitsa
25–49	0.85	(0.05–15.5)	0.91
50–99	8.13	(0.92–72.2)	0.06
≥100	2.78	(0.20–38.0)	0.44
Chronic transfusion therapyb
Current	0.52	(0.04–6.91)	0.62
Past	0.35	(0.03–3.97)	0.39
LR historyc
Not exclusively LR	0.81	(0.15–4.40)	0.81
Incomplete LR history	1.78	(0.28–11.4)	0.54
Days since last RBC transfusion	1.00	(0.999–1.002)	0.63
Splenectomy	0.25	(0.04–1.57)	0.14

LR, leukoreduction. Odds ratios (95% confidence intervals) for each predictor variable are shown.

^aReference group: <25 units;

^bReference group: never received chronic transfusion therapy;

^cReference group: exclusively LR units.