Adherence to inhaled corticosteroids prescribed once vs twice daily in children with asthma

Abstract

BackgroundSuboptimal adherence to inhaled corticosteroids (ICS) is associated with poor asthma control. Adult studies suggest that simplification of ICS regimen leads to better adherence. ObjectiveWe aimed to determine whether once-daily, compared with twice-daily, ICS dosing was associated with better adherence among children with asthma. MethodsWe conducted a retrospective observational study of children with asthma prescribed with either once-daily or twice-daily ICS monotherapy between 2011 and 2019. Our primary adherence outcome was the proportion of prescribed days covered (PPDC)—that is, the number of days for which the drug was dispensed by the pharmacy divided by the number of days for which it was prescribed. The impact of once-daily vs twice-daily ICS regimen on adherence was evaluated using linear multivariable regression analysis adjusting for covariates. Secondary outcomes included the proportion of patients with greater than or equal to 75% adherence analyzed using logistic regression models. ResultsA total of 232 children (61% boys; mean age of 5.8 [3.6] years) were included; 120 children were prescribed once-daily, and 112 twice-daily, ICS. The median PPDC was 66.8% for the once-daily and 57.9% for the twice-daily group (P = .03). Children prescribed once-daily ICS had a 7.2% (95% confidence interval, 1.3-13.1) greater mean PPDC compared with the twice-daily group and greater odds of having PPDC greater than or equal to 75% (71.4% vs 45.5%; odds ratio, 1.80; 95% confidence interval, 1.01-3.26). ConclusionOur findings suggest that once-daily dosing of ICS is associated with better medication adherence than twice-daily dosing. Whether the gain in adherence leads to better asthma control and health outcomes remains to be evaluated.