Individuals raised on a farm appear to have less asthma than individual raised elsewhere. However, selective migration might contribute to this as may also the suggested protection from farm environment. This study investigated if parents with asthma are less likely to raise their children on a farm. This study involved three generations: 6045 participants in ECRHS/RHINE cohorts (born 1945–1973, denoted G1), their 10,121 parents (denoted G0) and their 8260 offspring participating in RHINESSA (born 1963–1998, denoted G2). G2-offspring provided information on parents not participating in ECRHS/RHINE. Asthma status and place of upbringing for all three generations were reported in questionnaires by G1 in 2010–2012 and by G2 in 2013–2016. Binary regressions with farm upbringing as outcome were performed to explore associations between parental asthma and offspring farm upbringing in G0–G1 and G1–G2. Having at least one parent with asthma was not associated with offspring farm upbringing, either in G1–G2 (RR 1.11, 95% CI 0.81–1.52) or in G0–G1 (RR 0.99, 0.85–1.15). G1 parents with asthma born in a city tended to move and raise their G2 offspring on a farm (RR 2.00, 1.12–3.55), while G1 parents with asthma born on a farm were less likely to raise their G2 offspring on a farm (RR 0.34, 0.11–1.06). This pattern was not observed in analyses of G0–G1. This study suggests that the protective effect from farm upbringing on subsequent asthma development could not be explained by selective migration. Intriguingly, asthmatic parents appeared to change environment when having children.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
Timm S, Frydenberg M, Janson C, Campbell B, Forsberg B, Gislason T, Holm M, Jogi R, Omenaas E, Sigsgaard T, Svanes C, Schlünssen V. The urban-rural gradient in asthma: a population-based study in Northern Europe. Int J Environ Res Public Health. 2015;13:1–14. https://doi.org/10.3390/ijerph13010093.
Ege M, Mayer M. Exposure to environmental microorganisms and childhood asthma. N Engl J Med. 2011;364:701–9.
Von Ehrenstein OS, Von Mutius E, Illi S, Baumann L, Böhm O, Von Kries R. Reduced risk of hay fever and asthma among children of farmers. Clin Exp Allergy. 2000;30:187–93. https://doi.org/10.1046/j.1365-2222.2000.00801.x.
Bråbäck L, Hjern A, Rasmussen F. Trends in asthma, allergic rhinitis and eczema among Swedish conscripts from farming and non-farming environments. A nationwide study over three decades. Clin Exp Allergy. 2004;34:38–43.
Heederik D, Von Mutius E. Does diversity of environmental microbial exposure matter for the occurrence of allergy and asthma? J Allergy Clin Immunol. 2012;130:44–50. https://doi.org/10.1016/j.jaci.2012.01.067.
Strachan DP. Hay fever, hygiene and household size. BMJ. 1989;299:1259–60.
Ege MJ, Frei R, Bieli C, Schram-Bijkerk D, Waser M, Benz MR, Weiss G, Nyberg F, van Hage M, Pershagen G, Brunekreef B, Riedler J, Lauener R, Braun-Fahrländer C, von Mutius E. Not all farming environments protect against the development of asthma and wheeze in children. J Allergy Clin Immunol. 2007;119:1140–7. https://doi.org/10.1016/j.jaci.2007.01.037.
Wlasiuk G, Vercelli D. The farm effect, or: when, what and how a farming environment protects from asthma and allergic disease. Curr Opin Allergy Clin Immunol. 2012;12:461–6. https://doi.org/10.1097/ACI.0b013e328357a3bc.
Basinas I, Sigsgaard T, Kromhout H, Heederik D, Wouters IM, Schlünssen V. A comprehensive review of levels and determinants of personal exposure to dust and endotoxin in livestock farming. J Expo Sci Environ Epidemiol. 2013. https://doi.org/10.1038/jes.2013.83.
Bråbäck L, Hjern A, Rasmussen F, Van Schayck CP, Knottnerus JA. Selective migration contributes to a healthy worker effect in the farming population. J Clin Epidemiol. 2006;59:102–3. https://doi.org/10.1016/j.jclinepi.2005.08.003.
Vogelzang PFJ, van der Gulden JWJ, Tielen MJ, Folgering H, van Schayck CP. Health based selection for asthma, but not for chronic bronchitis, in pig farmers: an evidence based hypothesis. Eur Respir J. 1999;13:187. https://doi.org/10.1034/j.1399-3003.1999.13a34.x.
Eduard W, Schlünssen V, Sigsgaard T, Omland Ø, Pearce N, Douwes J. Can selection explain the protective effects of farming on asthma? Ann Agric Environ Med. 2015;22:467–9. https://doi.org/10.5604/12321966.1167715.
Klintberg B, Berglund N, Lilja G, Wickman M, van Hage-Hamsten M. Fewer allergic respiratory disorders among farmers’ children in a closed birth cohort from Sweden. Eur Respir J. 2001;17:1151–7. https://doi.org/10.1183/09031936.01.00027301.
Burney PGJ, Luczynska C, Chinn S, Jarvis D. The European community respiratory health survey. Eur Respir J. 1994;7:954–60. https://doi.org/10.1183/09031936.94.07050954.
Johannessen A, Verlato G, Benediktsdottir B, Forsberg B, Franklin K, Gislason T, Holm M, Janson C, Jögi R, Lindberg E, Macsali F, Omenaas E, Real FG, Saure EW, Schlünssen V, Sigsgaard T, Skorge TD, Svanes C, Torén K, Waatevik M, Nilsen RM, de Marco R. Longterm follow-up in European respiratory health studies—patterns and implications. BMC Pulm Med. 2014;14:63. https://doi.org/10.1186/1471-2466-14-63.
Glymour MM, Greenland S. Causal diagrams. In: Rothmann K, Greenland S, Lash T, editors. Modern Epidemiology. Lippincott Williams & Wilkins; 2012. p. 183–212.
Pekkanen J, Pearce N. Defining asthma in epidemiological studies. Eur Respir J. 1999;14:951–7. https://doi.org/10.1034/j.1399-3003.1999.14d37.x.
Kuiper IN, Svanes C, Benediktsdottir B, Bertelsen RJ, Bråbäck L, Dharmage SC, Holm M, Jögi R. Agreement in reporting of asthma by parents or offspring—the RHINESSA generation study. BMC Pulm Med. 2018. https://doi.org/10.1186/s12890-018-0687-4.
Kjøller M, Thoning H. Characteristics of non-response in the Danish Health Interview Surveys, 1987–1994. Eur J Public Health. 2005;15:528–35. https://doi.org/10.1093/eurpub/cki023.
Demarest S, Van Der Heyden J, Charafeddine R, Tafforeau J, Van Oyen H, Van Hal G. Socio-economic differences in participation of households in a Belgian national health survey. Eur J Public Health. 2013;23:981–5. https://doi.org/10.1093/eurpub/cks158.
Christensen S, Timm S, Janson C, Benediktsdottir B, Forsberg B, Holm M, Jogi R, Johannessen A, Omenaas E, Sigsgaard T, Svanes C, Schlünssen V. A clear urban-rural gradient of allergic rhinitis in a population-based study in Northern Europe. Eur Clin Respir J. 2016;3:33463.
Campbell B, Lodge C, Lowe A, Burgess J, Matheson M, Dharmage S. Exposure to ‘farming’ and objective markers of atopy: a systematic review and meta-analysis. Clin Exp Allergy. 2015;45:744–57. https://doi.org/10.1111/cea.12429.
Svanes C, Zock J-P, Antó J, Dharmage S, Norbäck D, Jarvis D, De Marco R, Plana E, Raherison C, Sunyer J. Do asthma and allergy influence subsequent pet keeping? An analysis of childhood and adulthood. J Allergy Clin Immunol. 2006. https://doi.org/10.1016/j.jaci.2006.06.017.
Bornehag CG, Sundell J, Hagerhed L, Janson S. Pet-keeping in early childhood and airway, nose and skin symptoms later in life. Allergy Eur J Allergy Clin Immunol. 2003;58:939–44. https://doi.org/10.1034/j.1398-9995.2003.00050.x.
The ECRHS/RHINE/RHINESSA study was supported by grants from The Faculty of Health, Aarhus University, Denmark (Project No. 240008), The Wood Dust Foundation (Project No. 444508795), The Danish Lung Association, the Swedish Heart and Lung Foundation, the Swedish Association Against Asthma and Allergy, the Swedish Association against Heart and Lung Disease, the Swedish Council for Working Life and Social Research, The Bror Hjerpstedt Foundation, The Vårdal Foundation for Health Care and Allergic Research, The Norwegian Research Council (Grant Nos. 214123, 230827/F20, 228174 and 135773/330), The Norwegian Asthma and Allergy Association, HelseVest Norway (Grant No. 911 631), The Icelandic Research Council, The University of Iceland Research Fund, The Icelandic GP’s Research Fund, The Estonian Science Foundation (Grant No. 4350), The Estonian Research Council (Grant No. PUT562), Melbourne University, National Health & Medical Research Council of Australia, SEPAR Spain, Sociedad Española de Neumologia y Cirugía Toracica Spain and Horizon2020 PHC1 (Grant No. 633212). For further information about funding sources, please consult www.rhinessa.net. Vivi Schlünssen and Cecilie Svanes are members of the COST BM1201 network. Signe Timm received a PhD scholarship from Aarhus University, Denmark.
Conflict of interest
Michael Abramson has received investigator-initiated grants from Pfizer and Boehringer-Ingelheim for unrelated research. The other authors declare no conflict of interest.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Electronic supplementary material
Below is the link to the electronic supplementary material.
About this article
Cite this article
Timm, S., Frydenberg, M., Abramson, M.J. et al. Asthma and selective migration from farming environments in a three-generation cohort study. Eur J Epidemiol 34, 601–609 (2019). https://doi.org/10.1007/s10654-019-00491-9
- Selective migration