Table 3.

Results of multivariable Cox regression analyses for PFS and OS.

	PFS			OS
Variables	HR	95% CI	P	HR	95% CI	P
Age (>60 y vs ≤60 y)	1.471	0.811–2.669	.204	1.669	0.732–3.805	.223
Gender (female vs male)	1.187	0.647–2.176	.580	1.454	0.638–3.310	.373
Creatinine (>106 umol/L vs ≤106 umol/L)	0.669	0.324–1.384	.279	0.855	0.324–2.256	.365
Calcium (>2.75 mmol/L vs ≤ 2.75 mmol/L)	0.970	0.406–2.318	.945	1.145	0.353–3.717	.821
Isotype (light chain vs non-light chain)	1.544	0.722–3.303	.263	1.183	0.451–3.105	.733
Bone disease status (absent vs present)	0.720	0.388–1.334	.306	0.495	0.227–1.079	.085
β2 microglobulin (<5.5 mg/L vs ≥ 5.5 mg/L)	1.790	0.900–3.562	.097	2.451	0.985–6.099	.054
Hemoglobin (<90 g/L vs ≥90 g/L)	2.107	0.866–5.127	.100	2.111	0.614–7.256	.236
Stage II (vs stage I)	2.763	0.348–21.920	.336	1.264	0.146–10.970	.832
Stage III (vs stage I)	4.586	0.570–36.877	.152	2.695	0.306–23.699	.372
RB1 (positive vs negative)	0.684	0.341–1.372	.285	0.812	0.324–2.040	.658
D13S319 (positive vs negative)	0.763	0.378–1.544	.452	0.902	0.356–2.285	.828
IGH (positive vs negative)	1.205	0.572–2.538	.625	0.982	0.358–2.688	.971
1q21 (positive vs negative)	1.355	0.709–2.591	.358	1.449	0.599–3.505	.410
P53 (positive vs negative)	0.276	0.125–0.611	.002	0.335	0.115–0.974	.045

CI = confidence interval, HR = hazard ratio, OS = overall survival, PFS = progression-free survival.