Table 1.

Patient characteristics

Cohort	SLE high	SLE low	HC
Individuals, no.	92	92	100
Age (median, range)	42 (14–73)	44 (19–81)	49 (16–81)
Disease duration (median, range)	4 (0–40)	8 (0–43)	N/A
Gender (% female)	89	89	85
Ethnicity (% white)	90	90	90
SLEDAI (median, range)	8 (2–28)	2 (0–12)	N/A
Active nephritis1 (%)	31	1	N/A
Nephritis ever (%)	43	43	N/A
class I (%)	0	0	N/A
class II (%)	0	0	N/A
class III (%)	6	6	N/A
class IV (%)	76	76	N/A
class V (%)	18	18	N/A
Anti-C1q antibodies current (%)	27	24	N/A
Immunosuppressive treatment (%)	40	50	N/A
Azathioprine (%)	25	25	N/A
CellCept (%)	18	17	N/A
Methotrexate (%)	2	0	N/A
Rituximab (%)	0	0	N/A
Cyclosporine (%)	9	9	N/A
Prednisone treatment (%)	68	68	N/A
Prednisone dose (median, range)	10 (0–40)	10 (0–40)	N/A
Hydroxychloroquine (%)	30	37	N/A

¹Defined as new onset of urinary casts, hematuria, pyuria and/or proteinuria according to SLEDAI-2 K [11]