Antinuclear autoantibodies are more prevalent in COPD in association with low body mass index but not with smoking history
- H P J Bonarius1,6,
- C A Brandsma1,
- H A M Kerstjens2,
- J A Koerts1,
- M Kerkhof3,
- E Nizankowska-Mogilnicka4,
- C Roozendaal5,
- D S Postma2,
- W Timens1
- 1Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, The Netherlands
- 2Department of Pulmonology, University Medical Center Groningen, University of Groningen, The Netherlands
- 3Department of Epidemiology and Statistics, University Medical Center Groningen, University of Groningen, The Netherlands
- 4Department of Pulmonology, Jagiellonian University Medical College, Cracow, Poland
- 5Laboratory Center University Medical Center Groningen, University of Groningen, The Netherlands
- 6IQ Therapeutics, Groningen, The Netherlands
- Correspondence to Professor Dr W Timens, Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands;
- Received 7 January 2010
- Accepted 26 August 2010
- Published Online First 3 November 2010
Background Chronic 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.
Methods The 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.
Results Patients with COPD had a significantly higher risk of being serum positive for ANAs (OR 3.12, 95% CI 1.68 to 5.76, p<0.001). ANAs were not significantly associated with age, smoking status, gender or pack-years of smoking. Within the COPD population, subjects with BMI <22 kg/m2 had a significantly higher risk of ANAs (OR 4.93, 95% CI 1.50 to 16.50, p=0.009) than those with normal or high BMI. The antibody repertoire of B cells in the lungs of patients with COPD had a high frequency of positively charged CDR3 residues, a feature which is associated with self-reactive antibodies.
Conclusion The results show that COPD is a heterogeneous disease with respect to the prevalence of ANAs. ANAs are primarily associated with the presence of COPD and with low BMI, but not with smoking and forced expiratory volume in 1 s.
- Chronic obstructive pulmonary disease
- body mass index
- COPD mechanisms
- COPD pathology
Funding This study was supported by a grant from the Dutch “Stichting Astma Bestrijding” and the Netherlands Asthma Foundation.
Competing interests None.
Ethics approval This study was conducted with the approval of the hospital medical ethical committees of Groningen and Cracow.
Provenance and peer review Not commissioned; externally peer reviewed.