Respiratory medication adherence in chronic lung disease of prematurity

Background: Chronic lung disease of prematurity (CLDP) is a frequent complication of premature birth. Infants and children with CLDP are often prescribed complex medication regimens, which can be difficult for families to manage.

Objective: We sought to determine whether non-adherence was associated with increased CLDP-related morbidities and to identify predictors of adherence.

Methods: Recruited caregivers of 194 children with CLDP completed questionnaires regarding self-reported adherence, respiratory outcomes, and quality of life (January 2008-June 2010). Adherence data were available for 176 subjects, of whom 143 had self-reported data only, and 33 had prescription claims data, which were used to calculate a medication possession ratio (MPR). Participants in the Prescription Claims Sample (n = 33) were more likely to have public insurance (P < 0.001).

Results: Self-reported adherence substantially overestimated medication possession; the mean MPR was 38.8% (n = 33) and was not associated with self-reported adherence (P = 0.71; n = 26). In a small sample, higher MPR was associated with decreased odds ratios of visiting the emergency department (ED) (OR = 0.75 for a 10% increase in MPR [95%CI: 0.58, 0.97]; P = 0.03; n = 74 questionnaires from 28 participants), activity limitations (OR = 0.71 [95%CI: 0.53, 0.95]; P = 0.02; n = 70 questionnaires from 28 participants), and rescue medication use (OR = 0.84 [95%CI: 0.73-0.98]; P = 0.03; n = 70 questionnaires from 28 participants). Increasing caregiver worries regarding medication efficacy and side effects were associated with lower MPR (P = 0.04 and 0.02, respectively; n = 62 questionnaires from 27 participants). Socio-demographic and clinical risk factors were not predictors of MPR (n = 33).

Conclusions: We found that non-adherence with respiratory medications was common in premature infants and children with CLDP. Using multiple timepoints in a small sample, non-adherence was associated with a higher likelihood of respiratory morbidities. Although self-reported adherence and demographic characteristics did not predict MPR, concerns about medications did. We suggest that addressing caregiver concerns about medications may improve adherence and ultimately decrease CLDP-related morbidities. Larger, prospective studies are needed to confirm these findings and determine which factors predict non-adherence.