Discovery (Sweden) | Replication (multiethnic) | |||||

LN (n=338) | SLE non-LN (n=620) | P value† | LN (n=603) | SLE non-LN (n=623) | P value† | |

Females, n (%) | 261 (77.2) | 565 (91.1) | <0.01 | 533 (88.4) | 583 (93.6) | <0.01 |

Age at diagnosis, year (SD)* | 30.8 (15.4) | 38.8 (15.7) | <0.01 | 28.2 (11.8) | 34.9 (12.9) | <0.01 |

SLE disease duration, year (SD)* | 17.1 (11.5) | 16.0 (12.1) | 0.19 | 9.6 (8.3) | 7.8 (8.3) | 0.18 |

Kidney biopsy (%) | 257 (76.0) | 171 (28.4) | ||||

Proliferative (%) | 153 (45.3) | 93 (15.4) | ||||

Pure membranous (%) | 41 (12.1) | 40 (6.6) | ||||

End-stage renal disease (%) | 35 (10.4) | 73 (12.1) | ||||

Hypertension (%) | 144 (42.6) | 151 (24.4) | <0.01 | |||

Diabetes mellitus (%) | 9 (2.7) | 30 (4.8) | 0.086 |

*Mean, SD.

†Independent samples t-test. Data are presented as mean (SD) or n (%), unless otherwise indicated. Patients fulfilled at least 4 of 11 ACR criteria for SLE.15 LN was defined by the ACR renal criterion or renal biopsy. Proliferative LN was defined as WHO Class III/IV, and pure membranous by WHO Class V. ESRD was defined as patients who required renal replacement therapy, dialysis or transplantation. The non-LN group of patients with SLE was defined as patients not fulfilling the ACR renal criterion.

ACR, American College of Rheumatology; ESRD, end-stage renal disease; LN, lupus nephritis.