Table 2.

Rise in PR3-ANCA level and relapse within 1 year

		Capture ELISA				Direct ELISA
	N*	HR	95% CI	P	c-index	HR	95% CI	P	c-index
All subjects	93
Any relapse	55	1.15	(0.62, 2.13)	0.648	0.50	2.24	(1.24, 4.08)	0.008	0.59
Severe relapse	42	1.71	(0.80, 3.71)	0.169	0.55	4.57	(2.16, 10.37)	<0.001	0.67
Granulomatous only at enrollment	15
Any relapse	13	0.36	(0.09, 1.38)	0.136	0.38	0.65	(0.17, 2.54)	0.532	0.49
Severe relapse	11	0.48	(0.11, 2.16)	0.340	0.41	1.01	(0.23, 4.48)	0.989	0.53
Renal involvement at enrollment	60
Any relapse	28	1.02	(0.44, 2.33)	0.954	0.48	2.16	(1.00, 4.64)	0.049	0.59
Severe relapse	21	2.33	(0.82, 6.93)	0.116	0.58	7.94	(2.72, 29.18)	<0.001	0.71
Alveolar hemorrhage at enrollment	24
Any relapse	14	1.69	(0.48, 6.24)	0.414	0.54	9.45	(2.58, 34.63)	<0.001	0.76
Severe relapse	11	3.18	(0.78, 14.94)	0.118	0.61	24.19	(3.05, 447.2)	<0.001	0.81
According to treatment group
Cyclophosphamide	43
Any relapse	24	0.63	(0.22, 1.70)	0.370	0.42	1.51	(0.59, 4.17)	0.400	0.55
Severe relapse	19	0.40	(0.09, 1.47)	0.197	0.42	2.84	(0.87, 11.40)	0.103	0.62
Rituximab	50
Any relapse	31	1.90	(0.85, 4.32)	0.117	0.57	3.09	(1.37,7.06)	0.006	0.60
Severe relapse	23	4.54	(1.61, 15.05)	0.007	0.68	5.80	(2.06, 19.77)	0.002	0.68

PR3-ANCA, antineutrophil cytoplasmic antibodies directed at proteinase 3; ELISA, enzyme-linked immunosorbent assay; HR, hazard ratio per Cox proportional hazards regression; CI, confidence interval; c-index, concordance index;

^*N = total number of first relapse events of the specified type after complete remission for each subcategory during follow-up