The association of obesity and asthma severity and control in children.

BACKGROUND: The association between obesity and asthma severity and control in children is not well understood.

OBJECTIVE: The objective of this study was to examine the association of childhood body mass index (BMI) percentile for age of 85% or greater with the number of β-agonist canisters dispensed, corticosteroid courses, emergency department visits, and hospitalizations for asthma.

METHODS: A retrospective cohort of 32,321 children aged 5 to 17 years and given a diagnosis of asthma who received at least 1 asthma (controller or rescue) medication and were enrolled in Kaiser Permanente from 2004-2008 was identified. Outcomes from electronic medical records included β-agonist canister and nebulizer units dispensed per year, hospitalizations and emergency department visits for asthma exacerbations, and oral corticosteroid courses. Potential confounding factors known to influence asthma outcomes were also collected: demographics, parental education level, asthma controller use, gastroesophageal reflux disease diagnosis, and diabetes mellitus diagnosis. Multiple logistic regression models were used to measure the independent association of BMI status with outcomes.

RESULTS: Even after adjusting for demographics, parental education level, asthma controller use, and gastroesophageal reflux disease and diabetes mellitus diagnoses, overweight (BMI percentile for age, 85% to 94%) and obese (BMI percentile for age, ≥ 95%) children were more likely to have increased β-agonists dispensed (odds ratio of 1.15 [95% CI, 1.02-1.27] and odds ratio of 1.17 [95% CI, 1.06-1.29], respectively) and increased risk for oral corticosteroids dispensed (odds ratio of 1.21 [95% CI, 1.13-1.29] and odds ratio of 1.28 [95% CI, 1.21-1.36], respectively) compared with normal-weight (BMI percentile for age, 16% to 84%) children.

CONCLUSIONS: Our findings suggest that childhood obesity is associated with an increased risk of worse asthma control and exacerbations.