title: Application of a prediction model for the progression of rheumatoid arthritis in patients with undifferentiated arthritis.
abstract: BACKGROUND
  Different prediction rules have been applied to patients with undifferentiated arthritis (UA) to identify those that progress to rheumatoid arthritis (RA). The Leiden Prediction Rule (LPR) has proven useful in different UA cohorts.
  
  
  OBJECTIVE
  To apply the LPR to a cohort of patients with UA of northeastern Mexico.
  
  
  METHODS
  We included 47 patients with UA, LPR was applied at baseline. They were evaluated and then classified after one year of follow-up into two groups: those who progressed to RA (according to ACR 1987) and those who did not.
  
  
  RESULTS
  43% of the AI patients developed RA. In the RA group, 56% of patients obtained a score ≤ 6 and only 15% ≥ 8. 70% who did not progress to RA had a score between 6 and ≤ 8. There was no difference in median score of LPR between groups, p=0.940.
  
  
  CONCLUSIONS
  Most patients who progressed to RA scored less than 6 points in the LPR. Unlike what was observed in other cohorts, the model in our population did not allow us to predict the progression of the disease.
authors.affiliation: Servicio de Reumatología, Departamento de Medicina Interna, Hospital Universitario «Dr. José Eleuterio González», Monterrey, Nuevo León, México.
authors.forename: Ana
authors.initials: A
authors.lastname: Arana-Guajardo
authors.affiliation: Servicio de Reumatología, Departamento de Medicina Interna, Hospital Universitario «Dr. José Eleuterio González», Monterrey, Nuevo León, México. Electronic address: lorenapb@hotmail.com.
authors.forename: Lorena
authors.initials: L
authors.lastname: Pérez-Barbosa
authors.affiliation: Servicio de Reumatología, Departamento de Medicina Interna, Hospital Universitario «Dr. José Eleuterio González», Monterrey, Nuevo León, México.
authors.forename: David
authors.initials: D
authors.lastname: Vega-Morales
authors.affiliation: Servicio de Reumatología, Departamento de Medicina Interna, Hospital Universitario «Dr. José Eleuterio González», Monterrey, Nuevo León, México.
authors.forename: Janett
authors.initials: J
authors.lastname: Riega-Torres
authors.affiliation: Servicio de Reumatología, Departamento de Medicina Interna, Hospital Universitario «Dr. José Eleuterio González», Monterrey, Nuevo León, México.
authors.forename: Jorge
authors.initials: J
authors.lastname: Esquivel-Valerio
authors.affiliation: Servicio de Reumatología, Departamento de Medicina Interna, Hospital Universitario «Dr. José Eleuterio González», Monterrey, Nuevo León, México.
authors.forename: Mario
authors.initials: M
authors.lastname: Garza-Elizondo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000175:diagnosis*; D003661:Decision Support Techniques; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008800:Mexico; D008875:Middle Aged; D011379:Prognosis
keywords: Artritis indiferenciada; Artritis reumatoide; Community Oriented Program for the Control of the Rheumatic Diseases; Diagnosis; Diagnóstico; Poliartritis; Polyarthritis; Programa Comunitario Orientado al Control de Enfermedades Reumáticas; Rheumatoid arthritis; Undifferentiated arthritis