title: Early discoid lupus erythematosus protects against renal disease in patients with systemic lupus erythematosus: longitudinal data from a large Latin American cohort.
abstract: OBJECTIVE
  The objective of this study was to examine whether early discoid lupus erythematosus (DLE) would be a protective factor for further lupus nephritis in patients with systemic lupus erythematosus (SLE).
  
  
  METHODS
  We studied SLE patients from GLADEL, an inception longitudinal cohort from nine Latin American countries. The main predictor was DLE onset, which was defined as physician-documented DLE at SLE diagnosis. The outcome was time from the diagnosis of SLE to new lupus nephritis. Univariate and multivariate survival analyses were conducted to examine the association of DLE onset with time to lupus nephritis.
  
  
  RESULTS
  Among 845 GLADEL patients, 204 (24.1%) developed lupus nephritis after SLE diagnosis. Of them, 10 (4.9%) had DLE onset, compared to 83 (12.9%) in the group of 641 patients that remained free of lupus nephritis (hazard ratio 0.39; P = 0.0033). The cumulative proportion of lupus nephritis at 1 and 5 years since SLE diagnosis was 6% and 14%, respectively, in the DLE onset group, compared to 14% and 29% in those without DLE (P = 0.0023). DLE onset was independently associated with a lower risk of lupus nephritis, after controlling for sociodemographic factors and disease severity at diagnosis (hazard ratio 0.38; 95% confidence interval 0.20-0.71).
  
  
  CONCLUSIONS
  Our data indicate that DLE onset reduces the risk of further lupus nephritis in patients with SLE, independently of other factors such as age, ethnicity, disease activity, and organ damage. These findings have relevant prognosis implications for SLE patients and their clinicians. Further studies are warranted to unravel the biological and environmental pathways associated with the protective role of DLE against renal disease in patients with SLE.
authors.affiliation: Department of Autoimmune Diseases, Institut Clínic de Medicina i Dermatologia, Barcelona, Spain.
authors.forename: G J
authors.initials: GJ
authors.lastname: Pons-Estel
authors.affiliation: Department of Dermatology, Emory School of Medicine, Atlanta, USA.
authors.forename: L D
authors.initials: LD
authors.lastname: Aspey
authors.affiliation: Division of Rheumatology, Emory School of Medicine, Atlanta, USA.
authors.forename: G
authors.initials: G
authors.lastname: Bao
authors.affiliation: Servicio de Reumatología, Hospital Provincial de Rosario, Rosario, Argentina.
authors.forename: B A
authors.initials: BA
authors.lastname: Pons-Estel
authors.affiliation: GLADEL Consultant, Universidad Nacional de Rosario, Rosario, Argentina.
authors.forename: D
authors.initials: D
authors.lastname: Wojdyla
authors.affiliation: Servicio de Reumatología, Hospital Privado, Córdoba, Argentina.
authors.forename: V
authors.initials: V
authors.lastname: Saurit
authors.affiliation: Servicio de Reumatología, Hospital Privado, Córdoba, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Alvarellos
authors.affiliation: Servicio de Reumatología, Hospital Privado, Córdoba, Argentina.
authors.forename: F
authors.initials: F
authors.lastname: Caeiro
authors.affiliation: Servicio de Reumatología, Hospital Privado, Córdoba, Argentina.
authors.forename: M J
authors.initials: MJ
authors.lastname: Haye Salinas
authors.affiliation: Departamento de Medicina, Universidade Federal da São Paulo (UNIFESP), São Paulo, Brazil.
authors.forename: E I
authors.initials: EI
authors.lastname: Sato
authors.affiliation: Sección de Reumatología, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina.|Fundación Dr Pedro M Catoggio para el Progreso de la Reumatología, Buenos Aires, Argentina.
authors.forename: E R
authors.initials: ER
authors.lastname: Soriano
authors.affiliation: Divisao de Reumatologia, Universidade Estadual de Campinas, Campinas, Brazil.
authors.forename: L T L
authors.initials: LT
authors.lastname: Costallat
authors.affiliation: Sección de Reumatología, Hospital del Salvador, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
authors.forename: O
authors.initials: O
authors.lastname: Neira
authors.affiliation: Facultad de Medicina, Universidad Nacional de Colombia, Bogota, Colombia.
authors.forename: A
authors.initials: A
authors.lastname: Iglesias-Gamarra
authors.affiliation: Servicio Nacional de Reumatología, Centro de Investigaciones Médico Quirúrgicas (CIMEQ), La Habana, Cuba.
authors.forename: G
authors.initials: G
authors.lastname: Reyes-Llerena
authors.affiliation: Centro de Investigación Clínica de Morelia, Morelia, México.
authors.forename: M H
authors.initials: MH
authors.lastname: Cardiel
authors.affiliation: Servicio de Reumatología, Hospital Nacional 'Guillermo Almenara Irigoyen', School of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Perú.
authors.forename: E M
authors.initials: EM
authors.lastname: Acevedo-Vásquez
authors.affiliation: Servicio de Reumatología, Hospital Universitario, Caracas, Venezuela.
authors.forename: R
authors.initials: R
authors.lastname: Chacón-Díaz
authors.affiliation: Division of Rheumatology, Emory School of Medicine, Atlanta, USA cdrenka@emory.edu.
authors.forename: C
authors.initials: C
authors.lastname: Drenkard
mesh_terms: D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007843:Latin America / Q000453:epidemiology; D008137:Longitudinal Studies; D008179:Lupus Erythematosus, Discoid / Q000453:epidemiology* / Q000503:physiopathology; D008180:Lupus Erythematosus, Systemic / Q000453:epidemiology* / Q000503:physiopathology; D008181:Lupus Nephritis / Q000453:epidemiology*; D008297:Male; D011379:Prognosis; D065840:Protective Factors; D012720:Severity of Illness Index; D016019:Survival Analysis; D013997:Time Factors; D055815:Young Adult
keywords: GLADEL cohort; Systemic lupus erythematosus; discoid lupus erythematosus; lupus nephritis; survival analysis