Table 1

Baseline demographic and clinical characteristics of the study subjects

CharacteristicMaintenance group (n=61)Withdrawal group (n=63)
Age, years41±1.744±1.6
Women55 (90)56 (89)
Disease duration, months147±86163±96
Quiescence duration, months56±668±7
Mean SELENA–SLEDAI score1.5±0.21.4±0.2
History of
 Lupus nephritis21 (34)26 (41)
 Neuropsychiatric lupus4 (7)8 (13)
 Arthritis43 (71)55 (87)
 Cutaneous lupus35 (57)39 (62)
 Serositis15 (25)17 (27)
SDI score0.5±0.10.7±0.2
Low C317 (28)18 (29)
Increased dsDNA binding29 (48)28 (46)
Low C3 and increased dsDNA binding10 (16)10 (16)
HCQ use57 (93)56 (89)
[HCQ], μg/L1071±66953±55
[HCQ]>750 µg/L*38/56† (68)38/56† (68)
Corticoid duration, months137±11145±13
Immunosuppressive drugs17 (28)16 (25)
 Methotrexate10 (16)3 (5)
 Azathioprine3 (5)1 (2)
 Mycophenolate mofetil4 (7)12 (19)
  • Values are expressed as n (%).

  • Plus–minus values are means±SD.

  • *Considered to be the therapeutic target.45

  • †Positive assay/number of patients taking HCQ. One HCQ serum concentration was missing in the maintenance group.

  • C3, Complement fraction 3; dsDNA, double-stranded DNA; [HCQ], blood concentration; HCQ, hydroxychloroquine;SDI, SLICC damage index; SELENA-SLEDAI, Safety of Estrogens in Lupus Erythematosus:National Assessment version of the Systemic Lupus Erythematosus Disease Activity Index; SLICC, Systemic Lupus International Collaborating Clinics.