Table 2.

Univariate and multivariate Cox regression analysis for overall survival

	univariate				multivariate
			initial model		final model
	HR	p	HR	p	HR	p
age>65 years	2.99	<0.0001	3.53	<0.0001	3.43	<0.0001
male sex	1.86	0.0018	1.84	0.0030	1.80	0.0038
ALC>14 × 109/L	1.67	0.0062	1.34	0.17	-
β2M>1 × ULN	1.43	<0.0001	1.51	0.06	1.59	0.029
LNR ≥3	3.06	<0.0001	1.20	0.59	-
Binet stage		<0.0001
A	ref		ref		ref
B	3.20		2.19	0.0352	2.77	<0.0001
C	4.95		2.86	0.0028	3.68	<0.0001
Rai stage		<0.0001
0	ref		ND
I-II	1.66		ND
III-IV	5.08		ND
CD38>30%	1.73	0.0038	1.03	0.88	-
ZAP-70>20%	1.53	0.0204	1.04	0.83	-
Unmutated IGHV	2.46	<0.0001	2.04	0.0008	2.04	0.0003
del17p	3.44	<0.0001	2.14	0.0015	2.06	0.0022
del11q	1.39	0.248	ND
Year of diagnosis		0.0130	(in model as strata)*		(in model as strata)*
<2001	ref
2001-2005	1.46
>2005	2.34
Therapy		0.106	ND
Chemotherapy	ref
Immunochemotherapy	0.6

Final model obtained by stepwise backward elimination

HR: hazard ratio; ND: not done