title: Presence of anticitrullinated protein antibodies in a large population-based cohort from the Netherlands.
abstract: OBJECTIVE
  To determine the prevalence of anticitrullinated protein antibodies (ACPAs) and their association with known rheumatoid arthritis (RA) risk factors in the general population.
  
  
  METHODS
  Lifelines is a multidisciplinary prospective population-based cohort study in the Netherlands. Cross-sectional data from 40 136 participants were used. The detection of ACPA was performed by measuring anti-CCP2 on the Phadia-250 analyser with levels ≥6.2 U/mL considered positive. An extensive questionnaire was taken on demographic and clinical information, including smoking, periodontal health and early symptoms of musculoskeletal disorders. RA was defined by a combination of self-reported RA, medication use for the indication of rheumatism and visiting a medical specialist within the last year.
  
  
  RESULTS
  Of the total 40 136 unselected individuals, 401 (1.0%) had ACPA level ≥6.2 U/mL. ACPA positivity was significantly associated with older age, female gender, smoking, joint complaints, RA and first degree relatives with rheumatism. Of the ACPA-positive participants, 22.4% had RA (15.2% had defined RA according to our criteria and 7.2% self-reported RA only). In participants without RA, 311 (0.8%) were ACPA-positive. In the non-RA group, older age, smoking and joint complaints remained significantly more frequently present in ACPA-positive compared with ACPA-negative participants.
  
  
  CONCLUSIONS
  In this large population-based study, the prevalence of ACPA levels ≥6.2 U/mL was 1.0% for the total group and 0.8% when excluding patients with RA. Older age, smoking and joint complaints were more frequently present in ACPA-positive Lifelines participants. To our knowledge, this study is the largest study to date on ACPA positivity in the general, mostly Caucasian population.
authors.affiliation: Department of Rheumatology and Clinical Immunology, Groningen, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: van Zanten
authors.affiliation: Department of Rheumatology and Clinical Immunology, Groningen, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: Arends
authors.affiliation: Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: C
authors.initials: C
authors.lastname: Roozendaal
authors.affiliation: Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: P C
authors.initials: PC
authors.lastname: Limburg
authors.affiliation: Department of Rheumatology and Clinical Immunology, Groningen, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Maas
authors.affiliation: Department of Rheumatology, LUMC, Leiden, The Netherlands.
authors.forename: L A
authors.initials: LA
authors.lastname: Trouw
authors.affiliation: Department of Rheumatology, LUMC, Leiden, The Netherlands.
authors.forename: R E M
authors.initials: REM
authors.lastname: Toes
authors.affiliation: Department of Rheumatology, LUMC, Leiden, The Netherlands.
authors.forename: T W J
authors.initials: TWJ
authors.lastname: Huizinga
authors.affiliation: Department of Rheumatology and Clinical Immunology, Groningen, The Netherlands.
authors.forename: H
authors.initials: H
authors.lastname: Bootsma
authors.affiliation: Department of Rheumatology and Clinical Immunology, Groningen, The Netherlands.
authors.forename: E
authors.initials: E
authors.lastname: Brouwer
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking / Q000453:epidemiology; D018771:Arthralgia / Q000453:epidemiology / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000453:epidemiology / Q000235:genetics / Q000276:immunology*; D001323:Autoantibodies / Q000276:immunology*; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008572:Menarche; D008875:Middle Aged; D015999:Multivariate Analysis; D009426:Netherlands; D010298:Parity; D010456:Peptides, Cyclic / Q000276:immunology*; D010518:Periodontitis / Q000453:epidemiology; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide
keywords: Ant-CCP; Epidemiology; Smoking