Characteristics at time-zero of patients with SLE who maintained, reduced or discontinued HCQ
| Characteristics at time-zero* | HCQ reduction n=564 | HCQ maintenance n=778 | HCQ discontinuation n=389 | HCQ maintenance n=577 |
| Female (%) | 90.6 | 87.9 | 90.2 | 87.0 |
| N missing | 0 | 0 | 0 | 0 |
| Race/Ethnicity (%) | ||||
| Caucasian | 51.6 | 55.1 | 42.9 | 55.6 |
| Asian | 24.3 | 14.7 | 19.3 | 13.9 |
| Black | 12.4 | 16.1 | 15.4 | 15.9 |
| Others | 10.6 | 13.3 | 21.4 | 13.9 |
| N missing | 6 (1.1) | 6 (0.8) | 4 (1.0) | 4 (0.7) |
| Age at SLE diagnosis (years, mean±SD) | 34.1±13.4 | 35.6±13.3 | 33.6±13.4 | 35.9±13.6 |
| N missing | 0 | 0 | 0 | 0 |
| No college/university education (%) | 34.0 | 38.9 | 38.8 | 39.9 |
| N missing | 6 (1.1) | 16 (2.0) | 3 (0.8) | 8 (1.4) |
| Geographic location (%) | ||||
| North America | 56.2 | 63.2 | 59.6 | 62.6 |
| Europe | 26.1 | 27.9 | 26.5 | 29.3 |
| Asia† | 17.7 | 8.9 | 13.9 | 8.1 |
| N missing | 0 | 0 | 0 | 0 |
| Time on HCQ (years, mean±SD) | 3.4±2.6 | 3.2±2.5 | 4.2±3.2 | 3.9±3.1 |
| N missing | 0 | 0 | 0 | 0 |
| HCQ daily dosage (mg, mean±SD) | 240±73 | 347±83 | 0 | 349±81 |
| N missing | 0 | 0 | 0 | 0 |
| SLE duration (years, mean±SD) | 5.5±3.0 | 5.4±3.0 | 6.7±3.5 | 6.1±3.4 |
| N missing | 0 | 0 | 0 | 0 |
| SLEDAI-2K ≥4 (%) | 39.9 | 35.7 | 38.0 | 36.0 |
| N missing | 15 (2.6) | 15 (1.9) | 11 (2.8) | 19 (3.3) |
| Renal damage (%) | 6.4 | 5.7 | 10.7 | 5.4 |
| N missing | 3 (0.5) | 5 (0.6) | 5 (1.3) | 2 (0.3) |
| Current smoker (%) | 25.9 | 33.2 | 29.6 | 31.5 |
| N missing | 3 (0.5) | 4 (0.5) | 7 (1.8) | 2 (0.3) |
| BMI (mean±SD) | 24.1±5.1 | 25.6±5.9 | 25.1±5.7 | 25.7±5.9 |
| N missing | 16 (2.8) | 30 (3.8) | 7 (1.8) | 23 (4.0) |
| Current prednisone (%) | 58.0 | 55.4 | 51.9 | 52.8 |
| N missing | 0 | 0 | 0 | 0 |
| Current immunosuppressors‡ (%) | 44.1 | 47.0 | 41.6 | 46.8 |
| N missing | 0 | 0 | 0 | 0 |
| Current biological agents§ (%) | 3.0 | 2.6 | 3.6 | 4.0 |
| N missing | 0 | 0 | 0 | 0 |
*Time-zero of each subcohort (not inception cohort entry).
†Asia was represented by a single country, South Korea.
‡Immunosuppressors included mycophenolate, azathioprine and methotrexate.
§Biologics included belimumab and rituximab.
BMI, body mass index; HCQ, hydroxychloroquine; SLE, systemic lupus erythematosus; SLEDAI-2K, SLE Disease Activity Index-2000.;