Table 3.

Multivariate analyses of PFS and OS under the Isa-PD regimen

Factors		PFS				OS
		Hazard ratio	95% CI	P-value	P-value*	Hazard ratio	95% CI	P-value	P-value*
White blood cell counts	≥ 3000/μl	1				1
	< 3000/μl	1.721	0.970–3.056	0.064	0.081	2.990	1.627–5.493	< 0.001	0.002
Lymphocyte/monocyte ratio	≥ 4	1				1
	< 4	2.494	1.216–5.116	0.013	0.009	5.188	1.840–14.630	0.002	< 0.001
Neutrophil/lymphocyte ratio	< 2.3	1				1
	≥ 2.3	1.409	0.790–3.907	0.231		1.467	0.782–2.751	0.231
κ/λ ratio	0.1–10	1				1
	≤ 0.1, ≥ 10	1.058	0.502–2.228	0.883		1.116	0.468–2.659	0.805
	NA	1.181	0.442–3.159	0.740		0.916	0.271–3.100	0.887
B2MG	< 3.5 mg/L	1				1
	≥ 3.5 mg/L	1.927	0.849–4.375	0.117		1.512	0.601–3.809	0.380
	NA	1.837	0.876–3.850	0.107		1.357	0.579–3.182	0.107
Prior regimen numbers	< 6	1				1
	≥ 6	2.177	1.214–3.901	0.009	0.012	1.838	0.897–3.768	0.097	0.065
Prior use of daratumumab	No	1				1
	Yes	2.458	1.357–4.453	0.003	0.011	2.014	1.032–3.929	0.040	0.062

Multivariate analyses of PFS and OS under the Isa-PD regimen were performed using the factors that showed P < 0.1 in univariate analysis. The Cox proportional hazard model was used to calculate the hazard ratio for each variable; the 95% CI and p-value are shown. *The P-value after the bootstrapping process (1000 samples) using the factors that showed P < 0.1 in multivariate analysis

PFS progression-free survival, OS overall survival, CI confidence interval, B2MG β₂ microglobulin