title: Classification of Systemic Lupus Erythematosus: Systemic Lupus International Collaborating Clinics Versus American College of Rheumatology Criteria. A Comparative Study of 2,055 Patients From a Real-Life, International Systemic Lupus Erythematosus Cohort.
abstract: OBJECTIVE
  The new Systemic Lupus International Collaborating Clinics (SLICC) 2012 classification criteria aimed to improve the performance of systemic lupus erythematosus (SLE) classification over the American College of Rheumatology (ACR) 1997 criteria. However, the SLICC 2012 criteria need further external validation. Our objective was to compare the sensitivity for SLE classification between the ACR 1997 and the SLICC 2012 criteria sets in a real-life, multicenter, international SLE population.
  
  
  METHODS
  We conducted a cross-sectional observational study of patients with a clinical diagnosis of SLE followed at the participating rheumatology centers and registered in the Portuguese and Spanish national registries. The sensitivity of the 2 classification sets was compared using McNemar's test. The sensitivity of ACR 1997 and SLICC 2012 was further examined in 5 subgroups, defined according to disease duration.
  
  
  RESULTS
  We included 2,055 SLE patients (female 91.4%, white 93.5%, mean ± SD age at disease onset 33.1 ± 14.4 years, mean ± SD age at SLE diagnosis 35.3 ± 14.7 years, and mean ± SD age at the time of the study 47.4 ± 14.6 years) from 17 centers. The sensitivity for SLE classification was higher with the SLICC 2012 than with the ACR 1997 (93.2% versus 85.6%; P < 0.0001). Of 296 patients not fulfilling the ACR 1997, 62.8% could be classified with the SLICC 2012. The subgroup of patients with ≤5 years since disease onset presented the largest difference in sensitivity between the SLICC 2012 and the ACR 1997 (89.3% versus 76.0%; P < 0.0001); this difference diminished with longer disease duration, and it was no longer significant for patients with >20 years of disease duration.
  
  
  CONCLUSIONS
  The SLICC 2012 criteria were more sensitive than the ACR 1997 criteria in real-life clinical practice in SLE. The SLICC 2012 criteria may allow patients to be classified as having SLE earlier in the disease course.
authors.affiliation: University of Beira Interior, Covilhã, Portugal, and Centro Hospitalar Universitário de Coimbra and University of Coimbra, Coimbra, Portugal.
authors.forename: Luís
authors.initials: L
authors.lastname: Inês
authors.affiliation: Instituto Português de Reumatologia, Lisboa, Portugal.
authors.forename: Cândida
authors.initials: C
authors.lastname: Silva
authors.affiliation: Hospital Universitario 12 de Octubre, Madrid, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Galindo
authors.affiliation: Hospital Universitario Gregorio Marañón, Madrid, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: López-Longo
authors.affiliation: Centro Hospitalar S. João, Porto, Portugal.
authors.forename: Georgina
authors.initials: G
authors.lastname: Terroso
authors.affiliation: Hospital de S. Maria, Lisboa, Portugal.
authors.forename: Vasco C
authors.initials: VC
authors.lastname: Romão
authors.affiliation: Hospital Universitario Doctor Negrín, Las Palmas de Gran Canaria, Spain.
authors.forename: Iñigo
authors.initials: I
authors.lastname: Rúa-Figueroa
authors.affiliation: Hospital Garcia de Orta, Almada, Portugal.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Santos
authors.affiliation: Complejo Hospitalario Universitario de Vigo, Vigo, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Pego-Reigosa
authors.affiliation: Hospital Egas Moniz, Lisboa, Portugal.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Nero
authors.affiliation: Unidade Local de Saúde do Alto Minho, Ponte de Lima, Portugal.
authors.forename: Marcos
authors.initials: M
authors.lastname: Cerqueira
authors.affiliation: Centro Hospitalar Universitário de Coimbra and University of Coimbra, Coimbra, Portugal.
authors.forename: Cátia
authors.initials: C
authors.lastname: Duarte
authors.affiliation: Instituto Português de Reumatologia, Lisboa, Portugal.
authors.forename: Luís C
authors.initials: LC
authors.lastname: Miranda
authors.affiliation: Centro Hospitalar S. João, Porto, Portugal.
authors.forename: Miguel
authors.initials: M
authors.lastname: Bernardes
authors.affiliation: Hospital de S. Maria, Lisboa, Portugal.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Gonçalves
authors.affiliation: Complejo Hospitalario Universitario de Vigo, Vigo, Spain.
authors.forename: Coral
authors.initials: C
authors.lastname: Mouriño-Rodriguez
authors.affiliation: Hospital Egas Moniz, Lisboa, Portugal.
authors.forename: Filipe
authors.initials: F
authors.lastname: Araújo
authors.affiliation: Unidade Local de Saúde do Alto Minho, Ponte de Lima, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Raposo
authors.affiliation: Hospital Infante D. Pedro, Aveiro, Portugal.
authors.forename: Anabela
authors.initials: A
authors.lastname: Barcelos
authors.affiliation: Centro Hospitalar Tondela-Viseu, Viseu, Portugal.
authors.forename: Maura
authors.initials: M
authors.lastname: Couto
authors.affiliation: Unidade Local de Saúde de Castelo Branco, Castelo Branco, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Abreu
authors.affiliation: Complejo Hospitalario Universitario de Vigo, Vigo, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Otón-Sanchez
authors.affiliation: Hospital de S. Maria, Lisboa, Portugal.
authors.forename: Carla
authors.initials: C
authors.lastname: Macieira
authors.affiliation: Hospital de S. Maria, Lisboa, Portugal.
authors.forename: Filipa
authors.initials: F
authors.lastname: Ramos
authors.affiliation: Universidade Nova de Lisboa, Centro Hospitalar de Lisboa Ocidental, and Hospital Egas Moniz, Lisboa, Portugal.
authors.forename: Jaime C
authors.initials: JC
authors.lastname: Branco
authors.affiliation: Centro Hospitalar Universitário de Coimbra and University of Coimbra, Coimbra, Portugal.
authors.forename: José A P
authors.initials: JA
authors.lastname: Silva
authors.affiliation: Hospital de S. Maria, Lisboa, Portugal.
authors.forename: Helena
authors.initials: H
authors.lastname: Canhão
authors.affiliation: Hospital Sierrallana, Torrelavega, Spain.
authors.forename: Jaime
authors.initials: J
authors.lastname: Calvo-Alén
mesh_terms: D000328:Adult; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000145:classification*; D008297:Male; D012219:Rheumatology / Q000592:standards*; D014481:United States