Comorbidities of asthma during childhood: possibly important, yet poorly studied.

Asthma in adults is associated with comorbidities such as obesity, gastro-oesophageal reflux, dysfunctional breathing and mental disorders. Herein, we provide an overview of the current state of evidence on these comorbidities in childhood asthma. The prevalence, known mechanisms and possible treatment options for each comorbid condition will be discussed. Obesity is an increasing health problem in children, but its relationship with asthma remains unclear. Allergic rhinitis is a very common comorbidity in asthma, both in children and in adults, but its effect on childhood asthma severity has not been studied. The prevalence and treatment options of dysfunctional breathing, a known comorbidity in adult asthma, have not yet been studied in paediatric asthma. Food allergies appear to cause more severe reactions in patients with asthma. Depressive disorders are more prevalent in childhood asthma than in healthy children, but seem to be poorly recognised and treated in children. Although gastro-oesophageal reflux is commonly thought to be a comorbid disease complicating asthma, it remains uncertain whether treatment improves asthma control. In conclusion, knowledge of asthma comorbidities in childhood is sparse. Further studies are urgently needed to identify the prevalence, and, more importantly, the effects of these comorbidities and their treatment on the degree of asthma control in children.