title: Effect of age at disease onset in the clinical profile of spondyloarthritis: a study of 1424 Brazilian patients.
abstract: OBJECTIVE
  To analyse demographic and clinical variables in patients with disease onset before and after 40, 45 and 50 years in a large series of Brazilian SpA patients.
  
  
  METHODS
  A common protocol of investigation was prospectively applied to 1424 SpA patients in 29 centres distributed through the main geographical regions in Brazil. The mean age at disease onset was 28.56 ± 12.34 years, with 259 patients (18.2%) referring disease onset after 40 years, 151 (10.6%) after 45 years and 81 (5.8%) after 50 years. Clinical and demographic variables and disease indices (BASDAI, BASFI, BASRI, MASES, ASQoL) were investigated. Ankylosing spondylitis was the most frequent disease (66.3%), followed by psoriatic arthritis (18%), undifferentiated SpA (6.7%), reactive arthritis (5.5%), and enteropathic arthritis (3.5%).
  
  
  RESULTS
  Comparing the groups according to age of disease onset, those patients with later onset presented statistical association with female gender, peripheral arthritis, dactylitis, nail involvement and psoriasis, as well as negative statistical association with inflammatory low back pain, alternating buttock pain, radiographic sacroiliitis, hip involvement, positive familial history, HLA-B27 and uveitis. BASDAI, BASFI and quality of life, as well as physicians and patient's global assessment, were similar in all the groups. Radiographic indices showed worse results in the younger age groups.
  
  
  CONCLUSIONS
  There are two different clinical patterns in SpA defined by age at disease onset: one with predominance of axial symptoms in the group with disease onset ≤ 40 years and another favouring the peripheral manifestations in those with later disease onset.
authors.affiliation: Hospital Evangélico de Curitiba, Brazil. tskare@onda.com.br
authors.forename: T L
authors.initials: TL
authors.lastname: Skare
authors.forename: N
authors.initials: N
authors.lastname: Leite
authors.forename: A B
authors.initials: AB
authors.lastname: Bortoluzzo
authors.forename: C R
authors.initials: CR
authors.lastname: Gonçalves
authors.forename: J A B
authors.initials: JA
authors.lastname: da Silva
authors.forename: A C
authors.initials: AC
authors.lastname: Ximenes
authors.forename: M B
authors.initials: MB
authors.lastname: Bértolo
authors.forename: S L E
authors.initials: SL
authors.lastname: Ribeiro
authors.forename: M
authors.initials: M
authors.lastname: Keiserman
authors.forename: R
authors.initials: R
authors.lastname: Menin
authors.forename: S
authors.initials: S
authors.lastname: Carneiro
authors.forename: V F
authors.initials: VF
authors.lastname: Azevedo
authors.forename: W P
authors.initials: WP
authors.lastname: Vieira
authors.forename: E das N
authors.initials: Ed
authors.lastname: Albuquerque
authors.forename: W A
authors.initials: WA
authors.lastname: Bianchi
authors.forename: R
authors.initials: R
authors.lastname: Bonfiglioli
authors.forename: C
authors.initials: C
authors.lastname: Campanholo
authors.forename: H M S
authors.initials: HM
authors.lastname: Carvalho
authors.forename: I P
authors.initials: IP
authors.lastname: Costa
authors.forename: A P
authors.initials: AP
authors.lastname: Duarte
authors.forename: M B O
authors.initials: MB
authors.lastname: Gavi
authors.forename: C L
authors.initials: CL
authors.lastname: Kohem
authors.forename: S A L
authors.initials: SA
authors.lastname: Lima
authors.forename: E S
authors.initials: ES
authors.lastname: Meirelles
authors.forename: I A
authors.initials: IA
authors.lastname: Pereira
authors.forename: M M
authors.initials: MM
authors.lastname: Pinheiro
authors.forename: E
authors.initials: E
authors.lastname: Polito
authors.forename: G G
authors.initials: GG
authors.lastname: Resende
authors.forename: F A C
authors.initials: FA
authors.lastname: Rocha
authors.forename: M B
authors.initials: MB
authors.lastname: Santiago
authors.forename: M de F L C
authors.initials: Mde F
authors.lastname: Sauma
authors.forename: P D
authors.initials: PD
authors.lastname: Sampaio-Barros
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D017668:Age of Onset; D000368:Aged; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index; D025241:Spondylarthritis / Q000453:epidemiology* / Q000503:physiopathology*; D013167:Spondylitis, Ankylosing / Q000453:epidemiology* / Q000503:physiopathology*; D055815:Young Adult