BACKGROUND: Asthma and obesity are common conditions that are strongly associated. This association might be due to shared genetic or environmental causes. OBJECTIVE: We sought to determine whether a shared genetic cause is responsible for the association between asthma and obesity and to estimate the magnitude of shared genetic cause. METHODS: The analyses were performed with 1001 monozygotic and 383 dizygotic same-sex twin pairs within the University of Washington Twin Registry. The presence of asthma was determined by self-report of a physician diagnosis of asthma, and body mass index (BMI) was calculated by using self-reported height and weight. Obesity was defined as a BMI of 30 or greater. The association between asthma and BMI was assessed by means of mixed-effects ordinal regression. Twin correlations examined the association of asthma and obesity. Univariate and bivariate structural equation models estimated the components of variance attributable to genetic and environmental effects. RESULTS: A strong association between asthma and BMI was identified in the sample population (P < .001). Substantial heritability was detected for asthma (53%) and obesity (77%), which is indicative of additive genetic influences on each disorder. The best-fitting model of shared components of variance indicated that 8% of the genetic component of obesity is shared with asthma. CONCLUSION: The covariation between obesity and asthma is predominantly caused by shared genetic risk factors for both conditions.
BACKGROUND:Asthma and obesity are common conditions that are strongly associated. This association might be due to shared genetic or environmental causes. OBJECTIVE: We sought to determine whether a shared genetic cause is responsible for the association between asthma and obesity and to estimate the magnitude of shared genetic cause. METHODS: The analyses were performed with 1001 monozygotic and 383 dizygotic same-sex twin pairs within the University of Washington Twin Registry. The presence of asthma was determined by self-report of a physician diagnosis of asthma, and body mass index (BMI) was calculated by using self-reported height and weight. Obesity was defined as a BMI of 30 or greater. The association between asthma and BMI was assessed by means of mixed-effects ordinal regression. Twin correlations examined the association of asthma and obesity. Univariate and bivariate structural equation models estimated the components of variance attributable to genetic and environmental effects. RESULTS: A strong association between asthma and BMI was identified in the sample population (P < .001). Substantial heritability was detected for asthma (53%) and obesity (77%), which is indicative of additive genetic influences on each disorder. The best-fitting model of shared components of variance indicated that 8% of the genetic component of obesity is shared with asthma. CONCLUSION: The covariation between obesity and asthma is predominantly caused by shared genetic risk factors for both conditions.
Authors: J C Celedón; L J Palmer; A A Litonjua; S T Weiss; B Wang; Z Fang; X Xu Journal: Am J Respir Crit Care Med Date: 2001-11-15 Impact factor: 21.405
Authors: J A Castro-Rodríguez; C J Holberg; W J Morgan; A L Wright; F D Martinez Journal: Am J Respir Crit Care Med Date: 2001-05 Impact factor: 21.405
Authors: Amy Murphy; Kelan G Tantisira; Manuel E Soto-Quirós; Lydiana Avila; Barbara J Klanderman; Stephen Lake; Scott T Weiss; Juan C Celedón Journal: Am J Hum Genet Date: 2009-07-02 Impact factor: 11.025
Authors: Erik Melén; Blanca E Himes; John M Brehm; Nadia Boutaoui; Barbara J Klanderman; Jody S Sylvia; Jessica Lasky-Su Journal: J Allergy Clin Immunol Date: 2010-09 Impact factor: 10.793
Authors: Juanita H J Vernooy; Niki D J Ubags; Guy G Brusselle; Jan Tavernier; Benjamin T Suratt; Guy F Joos; Emiel F M Wouters; Ken R Bracke Journal: Pulm Pharmacol Ther Date: 2013-03-27 Impact factor: 3.410