Antinuclear autoantibodies are more prevalent in COPD in association with low body mass index but not with smoking history

BackgroundChronic obstructive pulmonary disease (COPD) is associated with a higher prevalence of antinuclear autoantibodies (ANAs). However, a significant subgroup of patients is ANA negative. It remains to be determined which patient groups carry autoantibodies.MethodsThe association of smoking behaviour, disease status, gender, age and body mass index (BMI) with the presence of autoantibodies in the serum was determined in 124 patients with COPD and 108 non-COPD control subjects. In addition, the role of B cells in autoantibody generation in COPD was investigated by sequencing the antibody repertoire of B cells in the lungs of patients with COPD and of ex-smoking and never-smoking control subjects.ResultsPatients with COPD had a significantly higher risk of being serum positive for ANAs (OR 3.12, 95% CI 1.68 to 5.76, p