title: The clinically quiescent phase in early-diagnosed SLE patients: inception cohort study.
abstract: OBJECTIVE
  The aims of this study were to evaluate the incidence of clinical quiescence in early-diagnosed SLE patients and to determine factors associated with a prolonged clinically quiescent phase.
  
  
  METHODS
  We used an inception cohort of SLE patients seen between May 2007 and June 2012. All patients were assessed for clinical quiescence [modified SLEDAI 2000 (mSLEDAI-2K) score = 0, no new features of lupus activity o increase in treatment] then evaluated for the occurrence of flare (mSLEDAI-2K increase ≥4 and increased disease activity in one or more organ systems or an increase in treatment).
  
  
  RESULTS
  Ninety-five patients (88 females) with a mean age of 33.22 years (s.d. 13.24) and mean disease duration 2.79 months (s.d. 3.19) at cohort entry were enrolled during a mean observation period of 3.04 years (s.d. 1.38). Sixty-six patients (69.5%) reached clinical quiescence within 11.31 months (s.d. 1.10) of enrolment. Thirty-six patients (54.5%) had a disease flare during the observation period. The clinically quiescent phase was 28.2 months (s.d. 3.4). Cox regression analysis revealed that age ≥25 years at diagnosis [hazard ratio (HR) 2.57 (95% CI 1.23, 5.40)] and continued antimalarial drug treatment [HR 2.80 (95% CI 1.40, 5.58)] were associated with a longer clinically quiescent phase.
  
  
  CONCLUSIONS
  Most early-diagnosed SLE patients could have a good prognosis. Age at diagnosis ≥25 years or continued treatment with antimalarial drugs after reaching clinical quiescence may result in a longer clinically quiescent phase. More studies are needed to elucidate the mechanism of action for these protective effects.
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand nkasitan@mail.med.cmu.ac.th.
authors.forename: Nuntana
authors.initials: N
authors.lastname: Kasitanon
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Tulaporn
authors.initials: T
authors.lastname: Intaniwet
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Suparaporn
authors.initials: S
authors.lastname: Wangkaew
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Saowanee
authors.initials: S
authors.lastname: Pantana
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Waraporn
authors.initials: W
authors.lastname: Sukitawut
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Worawit
authors.initials: W
authors.lastname: Louthrenoo
mesh_terms: D000328:Adult; D000962:Antimalarials / Q000627:therapeutic use*; D015331:Cohort Studies; D018450:Disease Progression; D004305:Dose-Response Relationship, Drug; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012044:Regression Analysis; D012189:Retrospective Studies; D055502:Secondary Prevention; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000962:Antimalarials
keywords: SLE; antimalarial drugs; clinically quiescence; early-diagnosed; flare; remission