Table 2

Baseline predictors of time to occurrence of sustained doubling of serum creatinine and renal relapse

	Univariate analysis		Multivariate analysis
	HR (95% CI)	p Value	HR (95% CI)	p Value
Time to occurrence of sustained doubling of serum creatinine
Treatment (AZA/MP vs CY)	2.099 (0.592 to 7.444)	0.251		^†
Gender (male vs female)	1.900 (0.403 to 8.966)	0.417		^†
Caucasian (no vs yes)	3.864 (1.117 to 13.367)	0.033	3.864 (1.117–13.367)	0.033
Age (years)^‡	1.013 (0.959 to 1.070)	0.648		^†
Duration of SLE (years)^‡	0.989 (0.881 to 1.110)	0.846		^†
LN presenting symptom (yes vs no)	0.360 (0.076 to 1.694)	0.360		^†
Hypertension (present vs absent)	0.777 (0.165 to 3.669)	0.777		^†
C3 (% of lowest normal)^§	0.995 (0.971 to 1.019)	0.681		^†
C4 (% of lowest normal)^§	0.999 (0.990 to 1.008)	0.814		^†
Anti-dsDNA (positive vs negative)	0.478 (0.004 to 154431)	0.478		^†
Serum creatinine^§	1.006 (1.000 to 1.012)	0.036		^*
Proteinuria^§	0.990 (0.787 to 1.245)	0.930		^†
CI^§	1.024 (0.609 to 1.721)	0.930		^†
AI^§	0.942 (0.781 to 1.136)	0.533		^†
Time to occurrence of renal relapse
Treatment (AZA/MP vs CY)	4.623 (1.662 to 12.860)	0.003	4.556 (1.638 to 12.669)	0.004
Gender (male vs female)	3.031 (1.086 to 8.455)	0.034		^*
Caucasian (no vs yes)	1.841 (0.699 to 4.846)	0.217		^†
Age (years)^‡	1.012 (0.973 to 1.052)	0.565		^†
Duration of SLE (years)^‡	0.839 (0.707 to 0.996)	0.044		^*
LN presenting symptom (yes vs no)	2.230 (0.896 to 5.549)	0.085		^*
Hypertension (present vs absent)	0.705 (0.234 to 2.131)	0.536		^†
C3 (% of lowest normal)^§	1.006 (0.989 to 1.023)	0.484		^†
C4 (% of lowest normal)^§	0.998 (0.992 to 1.005)	0.601		^†
Anti-dsDNA (positive vs negative)	0.363 (0.120 to 1.096)	0.072		^*
Serum creatinine^§	1.000 (0.993 to 1.007)	0.961		^†
Proteinuria^§	1.110 (0.953 to 1.293)	0.179		^*
CI^§	0.898 (0.606 to 1.332)	0.593		^†
AI^§	0.974 (0.853 to 1.111)	0.692		^†

HR refers to the risk of occurrence of sustained doubling of serum creatinine and renal relapse.
↵* The variable was not selected during multivariate Cox regression analysis.
↵† The variable was not tested in multivariate Cox regression analysis because of a p value >0.2 in univariate Cox regression analysis.
↵‡ per year.
↵§ per 1 grade or 1 point.
AI, activity index; anti-dsDNA, anti-double-stranded DNA antibodies; AZA/MP, azathioprine/methylprednisolone; C3, complement factor 3; C4, complement factor 4; CI, chronicity index; CY, cyclophosphamide; HR, hazard ratio; LN, lupus nephritis; SLE, systemic lupus erythematosus.