Once- vs. twice-daily inhaled corticosteroid dosing for asthma boosts pediatric adherence

Simplification from twice-daily to once-daily dosing of inhaled corticosteroids for asthma correlated with better medication adherence in children, according to a study published in Annals of Allergy, Asthma & Immunology.

Olivier Drouin, MDCM, MSc, MPH, clinical assistant professor in the department of pediatrics at Université de Montréal, and colleagues wrote in their study that adherence to inhaled corticosteroids (ICS) is “notoriously low” among adults and children, with some clinics and hospitals reporting rates around 30% to 40% among pediatric patients.

Based on data that showed improved ICS adherence with once-daily vs. twice-daily dosing among adults with asthma, the researchers conducted a retrospective observational study of children who presented between 2011 and 2019 to the asthma clinic of Sainte-Justine University Hospital Center.

The study comprised 232 patients aged 1 to 17 years, which included the once-daily cohort (n = 120; mean age, 6.94 years; 43% girls; 58% white) and twice-daily cohort (n = 112; mean age, 5.59 years; 36% girls; 50% white). Baseline sociodemographic and asthma characteristics were similar between groups. However, ICS dose was lower and ciclesonide use was higher among the once-daily compared with the twice-daily cohort.

During follow-up, once-daily dosing correlated with a higher median proportion of prescribed days covered (PPDC) by dispensed supply compared with twice-daily treatment (66.8% vs. 57.9%; P = .03).

After adjusting for covariates, children prescribed once-daily ICS treatment had a 7.2% (95% CI, 1.3-13.1) higher PPDC compared with those prescribed twice-daily treatment.

For the secondary outcome, once-daily treatment correlated with a higher proportion of patients with “good adherence,” defined as a PPDC of 75% or higher (71.4% vs. 45.5%; adjusted OR = 1.8; 95% CI, 1.01-3.26).

The researchers also noted an overall trend toward 50% higher odds of having controlled or partially controlled asthma compared with poor control among the once-daily vs. twice-daily cohort (crude OR = 1.54; 95% CI, 0.95-2.51).

The impact of once- vs. twice-daily treatment showed no difference in the time to first exacerbation from baseline (adjusted HR = 0.71; 95% CI, 0.38-1.31) with numerically, but not significantly, fewer children in the once-daily cohort (15% vs. 22.3%) experiencing at least one episode during the first 6 months of the study.

“Other than dosing regimen, factors associated with drug adherence included age, deprivation index and persistent phenotype,” Drouin and colleagues wrote. “Similar to other studies, we found that children from lower socioeconomic status tended to have lower level of adherence to ICS than those from higher socioeconomic status.”

The researchers wrote that the reasons for this finding could not be interpreted from the current study design, but will be explored in a future prospective cohort study.

“Adequately powered studies are necessary to confirm if the improved adherence with once-daily dosing regimen translate in a meaningful improvement in asthma control and time to exacerbation,” Drouin and colleagues concluded.