Are BMI and adipokines associated with asthma, atopy and lung function in young adults previously hospitalized for bronchiolitis?

Abstract

Background: Children hospitalized for bronchiolitis have increased risk of asthma and low lung function persisting into adulthood, but the underlying mechanisms are poorly understood. Body mass index (BMI) and adipokines are associated with respiratory morbidity. We aimed to investigate if associations between BMI and adipokines and the outcomes asthma, atopy, and lung function differed between young adults previously hospitalized for bronchiolitis and control subjects.

Methods: This sub study of a historical cohort enrolled 185 young adults previously hospitalized for bronchiolitis and 146 matched control subjects. Exposures (BMI and the adipokines: adiponectin, leptin, resistin, and ghrelin) and outcomes (asthma, atopy, and lung function) were measured cross-sectionally at 17-20 years of age. Associations were tested in regression models, and differences between the post-bronchiolitis- and control group were tested by including interaction terms.

Results: BMI was associated with asthma and lung function, but we did not find that the associations differed between the post-bronchiolitis- and control group. We also found some associations between adipokines and outcomes, but only associations between adiponectin and forced vital capacity (FVC) and between resistin and current asthma differed between the groups (p-value interaction term 0.027 and 0.040 respectively). Adiponectin tended to be positively associated with FVC in the post-bronchiolitis group, with an opposite tendency in the control group. Resistin was positively associated with current asthma only in the control group.

Conclusion: The increased prevalence of asthma and impaired lung function observed in young adults previously hospitalized for bronchiolitis do not seem to be related to growth and fat metabolism.

Keywords: Adipokines; Asthma; Atopy; BMI; Bronchiolitis; Lung function.