RT Journal Article SR Electronic T1 Late Breaking Abstract - Childhood farming environment: Association to age at asthma diagnosis in a population-based study JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP OA1327 DO 10.1183/13993003.congress-2021.OA1327 VO 58 IS suppl 65 A1 Heidi Andersén A1 Pinja Ilmarinen A1 Jasmin Honkamäki A1 Leena E Tuomisto A1 Hanna Hisinger-Mölkänen A1 Helena Backman A1 Bo Lundbäck A1 Eva Rönmark A1 Lauri Lehtimäki A1 Anssi Sovijärvi A1 Päivi Piirilä A1 Hannu Kankaanranta YR 2021 UL http://erj.ersjournals.com/content/58/suppl_65/OA1327.abstract AB Background: Association of childhood farming environment to late-diagnosed asthma is poorly understood. Most studies are based on a population <50 years of age. The childhood farming environment and its microbiota reduce the likelihood of allergic asthma.Objective: Driving immunity differ in early- and late-diagnosed asthma. Therefore, we hypothesized that the childhood environment might modify asthma risk differently for early-onset and late-onset asthma.Methods: A cross-sectional population-based study was performed on subjects aged 20-69 years in Western Finland. The response rate was 52.5% and for those over 60 years 73.8%. We included 3864 participants, of whom 426 had physician-diagnosed asthma with a known age at diagnosis. Population was 3864 in early-diagnosed (0-11 years), 2832 in intermediate-diagnosed (12-39 years), and 1380 in late-diagnosed (40-69 years) in adjusted logistic regression analyses. To minimize bias, we used population aged 40-69 for intermediate-diagnosed and 60-69 years for late-diagnosed asthma analysis.Results: Childhood farming environment increased the odds of late-diagnosed asthma (aOR, 2.30; 95% CI, 1.12-4.69), but the odds were lower for early- (aOR, 0.49; 95% CI, 0.30-0.80) and intermediate-diagnosed asthma (aOR, 0.75; 95% CI, 0.47-1.18). The results remained after the exclusion of current and former farmers or co-existing COPD. The main result was validated in another cohort from Finland.Conclusions: Childhood farming environment was associated with higher odds for late-diagnosed asthma.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, OA1327.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).