Association between obesity and asthma in a twin cohort
Article first published online: 5 SEP 2007
Volume 62, Issue 10, pages 1199–1204, October 2007
How to Cite
Thomsen, S. F., Ulrik, C. S., Kyvik, K. O., Sørensen, T. I. A., Posthuma, D., Skadhauge, L. R., Steffensen, I. and Backer, V. (2007), Association between obesity and asthma in a twin cohort. Allergy, 62: 1199–1204. doi: 10.1111/j.1398-9995.2007.01480.x
- Issue published online: 5 SEP 2007
- Article first published online: 5 SEP 2007
- Accepted for publication 24 May 2007
- twin study
Background: Obesity is linked to asthma in a yet poorly understood manner. We examined the relationship between obesity and asthma in a population-based sample of twins.
Methods: From the cohorts born between 1953 and 1982, who were enrolled in The Danish Twin Registry, a total of 29 183 twin individuals participated in a nationwide questionnaire study, where data on height, weight and asthma were collected. Latent factor models of genetic and environmental effects were fitted using maximum likelihood methods.
Results: The age-adjusted risk of asthma was increased both in obese females, OR = 1.96 (1.45–2.64), P ≤ 0.001 and in obese males, OR = 1.59 (1.08–2.33), P = 0.02. According to best-fitting models, the heritability for obesity was 81% in males and 92% in females, whereas the heritability for asthma was 78% and 68% in males and females respectively. The age-adjusted genetic liabilities to obesity and asthma were significantly correlated only in females, r = 0.28 (0.16–0.38).
Conclusions: Obese subjects have an increased risk for asthma, which in females seems partly because of common genes.