8284122 Pi-genotypes and new onset asthma-like symptoms in farmers

<h3>Objectives</h3> To examine the connection between adult-onset asthma like symptoms and Alpha-1-antitrypsin (A-1-A) phenotype in farmers. <h3>Materials and Methods</h3> A 15-year follow up study of 917 Danish farming students and rural controls. Phenotypes of A-1-A phenotype and clinical examination were conducted at baseline and follow-up. At baseline A-1-A rare alleles wer found associated to non-specific bronchial responsiveness. We performed multiple Log regression assessing associations with adult-onset asthma. Asthma was defined as ‘definite or probable’ according to the ECHRS algorithm previously employed in the baseline study and the ECRHS study. <h3>Results</h3> Among the young farmers 155 had new-onset asthma. Controlling for smoking, atopy, and upbringing at dairy farm risk for new onset asthma-like symptoms according to Alpha-1-phenotype (Pi) were compared to the wild type (MM); OR (95% CI) MS : 0.55 (0,2 - 1.6) MZ : 0.69 (0.3 - 1.8) MX : 1.97 (0.2 - 20) SS: 1.95 (0.2 - 24) <h3>Conclusion</h3> There is no direct effect of the different Pi-types on the risk of new asthma in adulthood. A sensitivity analysis showed no difference in the risk estimates when we included NSBR in the model. However, the study is too small ie. The power is low, and results should be appreciated with cautiousness.