title: Increased risk of revision for infection in rheumatoid arthritis patients with total hip replacements.
abstract: Medical treatment of rheumatoid arthritis (RA) has changed dramatically over the last 15 years, including immune modulation. We investigated the risk of revision for infection after primary total hip replacement (THR) in patients with rheumatoid arthritis over a 16-year period, and compared it with that in THR patients with osteoarthritis (OA).
  
  
  
  We identified 13,384 THRs in RA patients and 377,287 THRs in OA patients from 1995 through 2010 in a dataset from the Nordic Arthroplasty Register Association (NARA). Kaplan-Meier survival curves, with revision for infection as the endpoint, were constructed. Cox regression analyses were performed to calculate the relative risk (RR) of revision for infection adjusted for age, sex, fixation technique, and year of primary surgery.
  
  
  
  RA patients had a 1.3 times (95% CI 1.0-1.6) higher risk of revision for infection. After 2001, this risk increased more for RA patients than for OA patients. During the first 3 months and from 8 years postoperatively, the risk of revision for infection was higher in RA patients with THRs fixated with antibiotic-loaded cement than in corresponding OA patients.
  
  
  
  We found a slightly higher overall risk of revision for infection in RA patients than in OA patients, but this difference was only present after 2001. In THRs with antibiotic-loaded cement, the risk of very early and late infections leading to revision was higher in RA patients than in OA patients.
authors.affiliation: The Norwegian Arthroplasty Register, Department of Orthopaedic Surgery, Haukeland University Hospital.
authors.forename: Johannes Cornelis
authors.initials: JC
authors.lastname: Schrama
authors.forename: Anne M
authors.initials: AM
authors.lastname: Fenstad
authors.forename: Håvard
authors.initials: H
authors.lastname: Dale
authors.forename: Leif
authors.initials: L
authors.lastname: Havelin
authors.forename: Geir
authors.initials: G
authors.lastname: Hallan
authors.forename: Søren
authors.initials: S
authors.lastname: Overgaard
authors.forename: Alma B
authors.initials: AB
authors.lastname: Pedersen
authors.forename: Johan
authors.initials: J
authors.lastname: Kärrholm
authors.forename: Göran
authors.initials: G
authors.lastname: Garellick
authors.forename: Pekka
authors.initials: P
authors.lastname: Pulkkinen
authors.forename: Antti
authors.initials: A
authors.lastname: Eskelinen
authors.forename: Keijo
authors.initials: K
authors.lastname: Mäkelä
authors.forename: Lars B
authors.initials: LB
authors.lastname: Engesæter
authors.forename: Bjørg-Tilde
authors.initials: BT
authors.lastname: Fevang
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000601:surgery*; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D006622:Hip Prosthesis / Q000382:microbiology*; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery*; D016459:Prosthesis-Related Infections / Q000453:epidemiology*; D012042:Registries; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D012537:Scandinavian and Nordic Countries / Q000453:epidemiology; D013997:Time Factors