Table 5.

Cox regression analysis of factors affecting mortality.

Covariates	Univariate	P	Multivariate	P
	Hazard ratio (95% confidence interval)		Hazard ratio (95% confidence interval)
Age of SLE onset, per year	1.06 (1.05–1.08)	<0.001	1.06 (1.04–1.08)	<0.001
SDI score at 10 years, per point	1.45 (1.32–1.59)	<0.001	1.60 (1.42–1.80)	<0.001
Male sex	2.29 (1.31–4.00)	0.004	1.30 (0.73–2.31)	0.38
Renal involvement	2.04 (1.37–3.02)	<0.001	1.36 (0.86–2.17)	0.19
Ever use of HCQ at 10 years	0.42 (0.28–0.63)	<0.001	0.54 (0.34–0.85)	0.008
Group 2 (vs. group 1)	0.61 (0.38–1.001)	0.05	0.76 (0.45–1.28)	0.30

SDI, systemic lupus erythematosus international collaborating clinics (SLICC) damage index; HCQ, hydroxychloroquine.