TY - JOUR T1 - Joint effect of obesity and <em>TNFA</em> variability on asthma: two international cohort studies JF - European Respiratory Journal JO - Eur Respir J SP - 1003 LP - 1009 DO - 10.1183/09031936.00140608 VL - 33 IS - 5 AU - F. Castro-Giner AU - M. Kogevinas AU - M. Imboden AU - R. de Cid AU - D. Jarvis AU - M. Mächler AU - W. Berger AU - P. Burney AU - K. A. Franklin AU - J. R. Gonzalez AU - J. Heinrich AU - C. Janson AU - E. Omenaas AU - I. Pin AU - T. Rochat AU - J. Sunyer AU - M. Wjst AU - J-M. Antó AU - X. Estivill AU - N. M. Probst-Hensch Y1 - 2009/05/01 UR - http://erj.ersjournals.com/content/33/5/1003.abstract N2 - Obesity is a risk factor for asthma. Adipose tissue expresses pro-inflammatory molecules including tumour necrosis factor (TNF), and levels of TNF are also related to polymorphisms in the TNF-α (TNFA) gene. The current authors examined the joint effect of obesity and TNFA variability on asthma in adults by combining two population-based studies. The European Community Respiratory Health Survey and the Swiss Cohort Study on Air Pollution and Lung and Heart Disease in Adults used comparable protocols, questionnaires and measures of lung function and atopy. DNA samples from 9,167 participants were genotyped for TNFA -308 and lymphotoxin-α (LTA) +252 gene variants. Obesity and TNFA were associated with asthma when mutually adjusting for their independent effects (odds ratio (OR) for obesity 2.4, 95% confidence interval (CI) 1.7–3.2; OR for TNFA -308 polymorphism 1.3, 95% CI 1.1–1.6). The association of obesity with asthma was stronger for subjects carrying the G/A and A/A TNFA -308 genotypes compared with the more common G/G genotype, particularly among nonatopics (OR for G/A and A/A genotypes 6.1, 95% CI 2.5–14.4; OR for G/G genotype 1.7, 95% CI 0.8–3.3). The present findings provide, for the first time, evidence for a complex pattern of interaction between obesity, a pro-inflammatory genetic factor and asthma. ER -