title: Occupational exposure to textile dust increases the risk of rheumatoid arthritis: results from a Malaysian population-based case-control study.
abstract: Lung exposures including cigarette smoking and silica exposure are associated with the risk of rheumatoid arthritis (RA). We investigated the association between textile dust exposure and the risk of RA in the Malaysian population, with a focus on women who rarely smoke.
  
  
  
  Data from the Malaysian Epidemiological Investigation of Rheumatoid Arthritis population-based case-control study involving 910 female early RA cases and 910 female age-matched controls were analysed. Self-reported information on ever/never occupationally exposed to textile dust was used to estimate the risk of developing anti-citrullinated protein antibody (ACPA)-positive and ACPA-negative RA. Interaction between textile dust and the human leucocyte antigen DR β-1 (HLA-DRB1) shared epitope (SE) was evaluated by calculating the attributable proportion due to interaction (AP), with 95% CI.
  
  
  
  Occupational exposure to textile dust was significantly associated with an increased risk of developing RA in the Malaysian female population (OR 2.8, 95% CI 1.6 to 5.2). The association between occupational exposure to textile dust and risk of RA was uniformly observed for the ACPA-positive RA (OR 2.5, 95% CI 1.3 to 4.8) and ACPA-negative RA (OR 3.5, 95% CI 1.7 to 7.0) subsets, respectively. We observed a significant interaction between exposure to occupational textile dust and HLA-DRB1 SE alleles regarding the risk of ACPA-positive RA (OR for double exposed: 39.1, 95% CI 5.1 to 297.5; AP: 0.8, 95% CI 0.5 to 1.2).
  
  
  
  This is the first study demonstrating that textile dust exposure is associated with an increased risk for RA. In addition, a gene-environment interaction between HLA-DRB1 SE and textile dust exposure provides a high risk for ACPA-positive RA.
authors.affiliation: Institute for Medical Research, Jalan Pahang, Kuala Lumpur, Malaysia Rheumatology Unit, Department of Medicine, Center for Molecular Medicine L8:O4, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Chun Lai
authors.initials: CL
authors.lastname: Too
authors.affiliation: Institute for Medical Research, Jalan Pahang, Kuala Lumpur, Malaysia.
authors.forename: Nor Asiah
authors.initials: NA
authors.lastname: Muhamad
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Ilar
authors.affiliation: Rheumatology Unit, Department of Medicine, Center for Molecular Medicine L8:O4, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Leonid
authors.initials: L
authors.lastname: Padyukov
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Alfredsson
authors.affiliation: Rheumatology Unit, Department of Medicine, Center for Molecular Medicine L8:O4, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Klareskog
authors.affiliation: Institute for Medical Research, Jalan Pahang, Kuala Lumpur, Malaysia.
authors.forename: Shahnaz
authors.initials: S
authors.lastname: Murad
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Camilla
authors.initials: C
authors.lastname: Bengtsson
mesh_terms: D000328:Adult; D000483:Alleles; D000906:Antibodies / Q000097:blood / Q000235:genetics; D001172:Arthritis, Rheumatoid / Q000209:etiology* / Q000235:genetics; D016022:Case-Control Studies; D004391:Dust; D000939:Epitopes; D005260:Female; D059647:Gene-Environment Interaction; D059811:HLA-DRB1 Chains / Q000235:genetics / Q000276:immunology; D006801:Humans; D008296:Malaysia; D008875:Middle Aged; D009784:Occupational Diseases / Q000209:etiology* / Q000235:genetics; D016273:Occupational Exposure / Q000009:adverse effects*; D010456:Peptides, Cyclic / Q000235:genetics / Q000276:immunology; D012307:Risk Factors; D013783:Textile Industry; D013784:Textiles / Q000009:adverse effects*
chemical_list: D000906:Antibodies; D004391:Dust; D000939:Epitopes; D059811:HLA-DRB1 Chains; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide
keywords: Ant-CCP; Epidemiology; Rheumatoid Arthritis