title: Obesity and asthma, what are the links?
abstract: OBJECTIVE
  Obesity is a major cause of morbidity accounting for approximately 300 000 deaths each year and about 7% of the health care budget with an economic impact greater than US dollar 100 billion annually in the United States. Obesity and its sequelae such as cardiovascular disease, diabetes, arthritis or cancer have been on the rise over the last decades. The parallel time trend with an increasing prevalence of asthma has induced a lively debate about a potential link between both conditions.
  
  
  RESULTS
  A number of prospective studies have shown that weight gain can antedate the development of asthma. Effect modification by sex may occur as some studies have shown effects of body mass index on asthma only among females. However, sex differences are not consistent. Several hypotheses have been proposed to explain the epidemiological associations including alterations in airway mechanics and immune responses, hormonal influences and genetic factors.
  
  
  CONCLUSIONS
  There is evidence that obesity and overweight are associated with the development of asthma. Yet, the mechanisms underlying this relation are unclear. Weight reduction among asthmatic patients can result in improvements of lung function demonstrating the potential clinical impact of the findings.
authors.affiliation: University Children's Hospital Munich, Munich, Germany. bschaub@med.uni-muenchen.de
authors.forename: Bianca
authors.initials: B
authors.lastname: Schaub
authors.forename: Erika
authors.initials: E
authors.lastname: von Mutius
mesh_terms: D001249:Asthma / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D006967:Hypersensitivity / Q000150:complications / Q000503:physiopathology; D009765:Obesity / Q000150:complications* / Q000503:physiopathology