Table 2.

Baseline demographics and patient characteristics.

CharacteristicsLN Patient Population, n = 176
Continuous variablesMean (SD)Median (min–max)
  Age at biopsy date, yrs (Day 0)36.1 (11.81)35.0 (18.00–76.00)
  Serum creatinine, mg/dl1.0 (0.63)0.8 (0.40–4.70)
  Urinary creatinine, mg/dl135.7 (110.15)109.0 (27.00–655.00)
  Urinary protein:creatinine ratio1.5 (1.80)0.8 (0–9.91)
  Urinary RBC (RBC/hpf)8.6 (20.07)2.5 (0–100.00)
  SLICC Damage Index score2.2 (2.61)1.0 (0–12.00)
Categorical variables, n (%)
  LN ISN classIII44 (25.0)
IV51 (29.0)
V40 (22.7)
Mixed41 (23.3)
  Initiated induction therapy in 6 mos before or after biopsy dateCYC28 (15.9)
MMF88 (50.0)
AZA17 (9.7)
RTX0
None43 (24.4)
CYC or MMF or AZA or RTX133 (75.6)
  Decade of biopsy1989 or earlier2 (1.1)
1990–199936 (20.5)
2000–2009123 (69.9)
2010–201315 (8.5)
  SexFemale161 (91.5)
  Race/ethnicityBlack94 (53.4)
Other82 (46.6)
  Urine protein dipstick* (semiquantitative) category018 (10.2)
0.512 (6.8)
123 (13.1)
248 (27.3)
363 (35.8)
411 (6.3)
50
HTN**138 (78.4)
Diabetes***29 (16.5)
History of MI4 (2.3)
Any HCQ use from Day 0 to Month 24123 (69.9)
Any prednisone use from Day 0 to Month 24164 (93.2)
  • * Dipstick results were selected for the purposes of describing the cohort at baseline, because this particular method of measuring proteinuria was complete for all patients during the baseline window.

  • ** Defined as systolic blood pressure ≥ 140 or diastolic blood pressure ≥ 90 mmHg on 2 or more occasions, or HTN recorded as part of the SDI at any clinic visit.

  • *** Renal biopsy established that proteinuria was SLE-related and not diabetes-related. AZA: azathioprine; CYC: cyclophosphamide; ISN: International Society of Nephrology; LN: lupus nephritis; MI: myocardial infarction; MMF: mycophenolate mofetil; RBC/hpf: red blood cells per high power field; RTX: rituximab; SDI: SLICC Damage Index; SLICC: Systemic Lupus International Collaborating Clinics; HCQ: hydroxychloroquine; HTN: hypertension; SLE: systemic lupus erythematosus.