Nonadherence to inhaled corticosteroids: A characteristic of the pediatric obese-asthma phenotype?

BACKGROUND

Children with excess weight and asthma tend to respond less well to inhaled corticosteroids (ICS) than children with normal weight, potentially resulting in nonadherence to ICS.

OBJECTIVES

To assess whether excess weight (body mass index ≥85th percentile) was associated with general, unintentional, and intentional nonadherence to ICS in children with asthma.

METHODS

We analyzed data from 566 children aged 4-13 years with asthma, who used ICS as maintenance therapy, from the cross-sectional Pharmacogenetics of Asthma medication in Children: Medication with Anti-inflammatory effects study. General nonadherence was measured objectively with the proportion of days covered (<50%) and subjectively with the parent-reported Medication Adherence Rating Scale (MARS <21) reflecting parent-reported nonadherent behavior. Unintentional and intentional nonadherence were defined as forgetting to take medication and deliberately changing or skipping doses, respectively, from specific items of the MARS. We performed logistic regression analyses, stratifying estimates by asthma severity and age group.

RESULTS

Excess weight was associated with a trend towards increased odds of parent-reported nonadherent behavior (odds ratio [OR]: 1.54; 95% confidence interval [CI]: 0.84-2.81) and objectively measured general nonadherence, but only in moderate-to-severe asthma (OR: 1.71; 95% CI: 0.84-3.48). The odds of intentional, but not unintentional, nonadherence seemed to be greater in children with excess weight than normal weight (OR: 1.94; 95% CI: 0.94-4.01), and the association appeared to be stronger in younger (OR: 2.17; 95% CI 1.00-4.73) versus older children (OR: 1.18; 95% CI: 0.36-3.94).

CONCLUSIONS

Excess weight was associated with general nonadherence to ICS, but only in children with moderate-to-severe asthma, and nonadherent behavior, which seemed to be intentional.