title: Predictors of Chikungunya rheumatism: a prognostic survey ancillary to the TELECHIK cohort study.
abstract: BACKGROUND
  Long-lasting relapsing or lingering rheumatic musculoskeletal pain (RMSP) is the hallmark of Chikungunya virus (CHIKV) rheumatism (CHIK-R). Little is known on their prognostic factors. The aim of this prognostic study was to search the determinants of lingering or relapsing RMSP indicative of CHIK-R.
  
  
  METHODS
  Three hundred and forty-six infected adults (age≥15 years) having declared RMSP at disease onset were extracted from the TELECHIK cohort study, Reunion island, and analyzed using a multinomial logistic regression model. We also searched for the predictors of CHIKV-specific IgG titres, assessed at the time of a serosurvey, using multiple linear regression analysis.
  
  
  RESULTS
  Of these, 111 (32.1%) reported relapsing RMSP, 150 (43.3%) lingering RMSP, and 85 (24.6%) had fully recovered (reference group) on average two years after acute infection. In the final model controlling for gender, the determinants of relapsing RMSP were the age 45-59 years (adjusted OR: 2.9, 95% CI: 1.0, 8.6) or greater or equal than 60 years (adjusted OR: 10.4, 95% CI: 3.5, 31.1), severe rheumatic involvement (fever, at least six joints plus four other symptoms) at presentation (adjusted OR: 3.6, 95% CI: 1.5, 8.2), and CHIKV-specific IgG titres (adjusted OR: 3.2, 95% CI: 1.8, 5.5, per one unit increase). Prognostic factors for lingering RMSP were age 45-59 years (adjusted OR: 6.4, 95% CI: 1.8, 22.1) or greater or equal than 60 years (adjusted OR: 22.3, 95% CI: 6.3, 78.1), severe initial rheumatic involvement (adjusted OR: 5.5, 95% CI: 2.2, 13.8) and CHIKV-specific IgG titres (adjusted OR: 6.2, 95% CI: 2.8, 13.2, per one unit increase). CHIKV specific IgG titres were positively correlated with age, female gender and the severity of initial rheumatic symptoms.
  
  
  CONCLUSIONS
  Our data support the roles of age, severity at presentation and CHIKV specific IgG titres for predicting CHIK-R. By identifying the prognostic value of the humoral immune response of the host, this work also suggest a significant contribution of the adaptive immune response to the physiopathology of CHIK-R and should help to reconsider the paradigm of this chronic infection primarily shifted towards the involvement of the innate immune response.
authors.forename: Patrick
authors.initials: P
authors.lastname: Gérardin
authors.forename: Adrian
authors.initials: A
authors.lastname: Fianu
authors.forename: Alain
authors.initials: A
authors.lastname: Michault
authors.forename: Corinne
authors.initials: C
authors.lastname: Mussard
authors.forename: Karim
authors.initials: K
authors.lastname: Boussaïd
authors.forename: Olivier
authors.initials: O
authors.lastname: Rollot
authors.forename: Philippe
authors.initials: P
authors.lastname: Grivard
authors.forename: Somar
authors.initials: S
authors.lastname: Kassab
authors.forename: Eric
authors.initials: E
authors.lastname: Bouquillard
authors.forename: Gianandrea
authors.initials: G
authors.lastname: Borgherini
authors.forename: Bernard-Alex
authors.initials: BA
authors.lastname: Gaüzère
authors.forename: Denis
authors.initials: D
authors.lastname: Malvy
authors.forename: Gérard
authors.initials: G
authors.lastname: Bréart
authors.forename: François
authors.initials: F
authors.lastname: Favier
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000276:immunology; D065632:Chikungunya Fever / Q000150:complications / Q000276:immunology* / Q000473:pathology*; D015331:Cohort Studies; D003625:Data Collection; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012216:Rheumatic Diseases / Q000276:immunology* / Q000473:pathology*; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G