Maternal and personal cigarette smoking synergize to increase airflow limitation in adults

McConnachie, A. , Davey Smith, G., Upton, M. N., Hart, C. L. and Watt, G. C.M. (2004) Maternal and personal cigarette smoking synergize to increase airflow limitation in adults. American Journal of Respiratory and Critical Care Medicine, 169(4), pp. 479-487. (doi: 10.1164/rccm.200211-1357OC)

Abstract

Susceptibility of the lungs to cigarette smoke is poorly understood. It is not known whether maternal smoking increases chronic obstructive pulmonary disease (COPD) risk. In 1998 we reported an inverse association between maternal smoking (prerecorded) and FEV₁ in adults. Because FEV₁ and FVC are strongly correlated, it is unclear whether the association in question reflects a link with lung volume, airflow limitation, or both. We extended our original analysis to investigate whether maternal and personal smoking synergize to increase airflow limitation. We estimated residual FEV₁ to express FEV₁ variation that was not associated with FVC. Maternal smoking was inversely associated with FVC and FEV₁ irrespective of personal smoking. It was inversely associated with FEV1/FVC, forced midexpiratory flow rates (FEF_25–75 [mean forced expiratory flow during the middle half of the FVC], FEF_25–75/FVC), and residual FEV₁ in current smokers but not in never or former smokers (heterogeneity p = 0.016, 0.024, 0.021, and 0.016, respectively). We tested the clinical relevance of findings in ever smokers without asthma: 10 cigarettes/day maternal smoking increased prevalent COPD by 1.7 (95% confidence interval: 1.2–2.5) after adjustment for covariates. Maternal smoking impairs lung volume irrespective of personal smoking and appears to synergize with personal smoking to increase airflow limitation and COPD.<p></p>

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: McConnachie, Professor Alex and Hart, Dr Carole and Davey Smith, Professor George and Upton, Dr Mark and Watt, Professor Graham
• Authors: McConnachie, A., Davey Smith, G., Upton, M. N., Hart, C. L., and Watt, G. C.M.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Robertson Centre; College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Public Health; College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > General Practice and Primary Care; College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing > Centre for Population and Health Sciences; College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing > Clinical Specialities
• Journal Name: American Journal of Respiratory and Critical Care Medicine
• Publisher: American Thoracic Society
• ISSN: 1073-449X
• ISSN (Online): 1535-4970
• Published Online: 20 November 2003