title: Anti-cyclic citrullinated peptide (CCP) antibody in patients with wood-smoke-induced chronic obstructive pulmonary disease (COPD) without rheumatoid arthritis.
abstract: Citrullination, a post-translational modification of proteins, is increased in inflammatory processes and is known to occur in smokers. It can induce anti-cyclic citrullinated peptide (CCP) antibodies, the most specific serologic marker for rheumatoid arthritis. Thus far, the incidence of autoimmunity in patients with wood-smoke-induced chronic obstructive pulmonary disease (COPD) resulting in anti-CCP production has not been examined. We hypothesise that anti-CCP antibody level in these patients should be higher than that in healthy subjects. A total of 112 non-rheumatoid arthritis patients, including 56 patients with wood-smoke-induced COPD and 56 patients with tobacco-induced COPD, and 56 healthy non-smoker controls were included. The serum anti-CCP antibody levels were measured and compared between the groups and against smoke exposure and clinical characteristics. The mean anti-CCP antibody levels in wood-smoke-induced COPD group were significantly higher than those in tobacco-induced COPD group (p = 0.03) and controls (p = 0.004). Furthermore, 8 (14.2 %) patients with wood-smoke-induced COPD, 4 (7.14 %) with tobacco-induced COPD and 2 (3.57 %) controls exceeded the conventional cut-off of anti-CCP antibody positivity. No relationship was found between the anti-CCP antibody level and age, gender, duration of disease, Pack-years of smoking, and duration of exposure to wood smoke. Moreover, correlations between anti-CCP antibodies and severity of airflow limitation, CAT scores, mMRC scores of dyspnoea, and GOLD staging of COPD severity were not significant. Wood-smoke-induced COPD could significantly increase the anti-CCP antibody level in non-rheumatoid arthritis patients when compared with that in patients with tobacco-induced COPD and healthy controls.
authors.affiliation: Internal Medicine Department, School of Medicine, Kurdistan University of Medical Sciences, Sanandaj, Iran, naseh.sigari@muk.ac.ir.
authors.forename: Naseh
authors.initials: N
authors.lastname: Sigari
authors.forename: Nasrin
authors.initials: N
authors.lastname: Moghimi
authors.forename: Farhad Saber
authors.initials: FS
authors.lastname: Shahraki
authors.forename: Shilan
authors.initials: S
authors.lastname: Mohammadi
authors.forename: Daem
authors.initials: D
authors.lastname: Roshani
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000276:immunology; D001323:Autoantibodies / Q000097:blood*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000209:etiology / Q000276:immunology*; D012906:Smoke / Q000009:adverse effects*
chemical_list: D001323:Autoantibodies; D010456:Peptides, Cyclic; D012906:Smoke; C487763:cyclic citrullinated peptide