Get access

The association of preterm birth with severe asthma and atopic dermatitis: a national cohort study

Authors

  • Håvard Trønnes,

    Corresponding author
    1. Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
    2. Department of Pediatrics, Haukeland University Hospital, Bergen, Norway
    • Correspondence

      Håvard Trønnes, Department of Global Public Health and Primary Care, University of Bergen, Kalfarveien 31, NO-5020 Bergen, Norway

      Tel.: +47 55586190

      Fax: +47 55588561

      E-mail: havard.tronnes@igs.uib.no

    Search for more papers by this author
  • Allen J. Wilcox,

    1. Epidemiology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Durham, NC, USA
    Search for more papers by this author
  • Rolv Terje Lie,

    1. Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
    2. Medical Birth Registry of Norway, Norwegian Institute of Public Health, Bergen, Norway
    Search for more papers by this author
  • Trond Markestad,

    1. Department of Pediatrics, Haukeland University Hospital, Bergen, Norway
    2. Department of Clinical Medicine, University of Bergen, Bergen, Norway
    Search for more papers by this author
  • Dag Moster

    1. Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
    2. Department of Pediatrics, Haukeland University Hospital, Bergen, Norway
    3. Medical Birth Registry of Norway, Norwegian Institute of Public Health, Bergen, Norway
    Search for more papers by this author

Abstract

Background

Asthma and atopic dermatitis are both regarded as atopic diseases. Being born too early is associated with increased risk of asthma, but some studies have indicated that the opposite might be true for atopic dermatitis. We explored in more detail the associations between preterm birth, asthma, and atopic dermatitis.

Methods

We analyzed data from Norwegian registries with prospectively collected data. All live births in Norway from 1967 through 2001 were followed through 2005 by linking the Medical Birth Registry of Norway to the National Insurance Scheme and to Statistics Norway. Only severe asthma and atopic dermatitis were registered in the National Insurance Scheme.

Results

Of a total of 1,760,821 children, we identified 9,349 cases (0.5%) with severe asthma and 6,930 cases (0.4%) with severe atopic dermatitis. Compared with children born at term (37–41 wk gestation), preterm birth was associated with increased odds for severe asthma (odds ratio (OR) 1.7 (95% confidence interval (CI): 1.6–1.8) for 32–36 wk gestation and OR 3.6 (95% CI: 3.1–4.2) for 23–31 wk) and decreased odds for severe atopic dermatitis (OR 0.9 (95% CI: 0.8–1.0) for 32–36 wk gestation and OR 0.7 (95% CI: 0.5–1.0) for 23–31 wk). Adjustment for perinatal and socio-demographic factors weakened the association between gestational age and severe asthma, while slightly strengthening the association between gestational age and severe atopic dermatitis.

Conclusions

Preterm birth was associated with increased risk of severe asthma and decreased risk of severe atopic dermatitis.

Get access to the full text of this article

Ancillary