Advanced understanding of modifiable predictors of health care use in pediatric chronic illness is critical to reducing health care costs. We examined the relationship between medication non-adherence and health care use in children and adolescents who have a chronic medical condition.
A systematic review of articles by using PubMed, PsycINFO, and CINAHL was conducted. Additional studies were identified by searching reference sections of relevant manuscripts. Studies that tested the relationship between medication non-adherence and health care use (ie, hospitalizations, emergency department visits, outpatient visits) or cost in children and adolescents (mean age ≤18 years) who have a chronic medical condition were included. Extraction of articles was completed by using predefined data fields.
Ten studies met our inclusion criteria. Nine of the 10 studies reviewed (90%) demonstrated a relationship between medication non-adherence and increased health care use. The directionality of this relationship varied depending on the outcome variable of interest.
Medication non-adherence is related to increased health care use in children and adolescents who have a chronic medical condition and should be addressed in clinical care. Future studies should include randomized controlled trials examining the impact of adherence promotion efforts on health care use and costs.
It was with great interest that I read this article reporting the link between adherence rates and health care utilization in childhood chronic diseases. The finding of this excellent meta-analysis that poor adherence leads to poor disease control and an increased need for acute medical care are of no surprise to anyone in the field.
One of the most interesting points to come from this article is the diversity of methods used to assess adherence in the studies included. Given the proven importance of adherence in chronic disease, it is frustrating to note the lack of universal and objective measurement tools. As referenced in McGrady's discussion, in 2009 Quittner et al assessed the evidence- base for the various methods of adherence assessment. They were divided into 5 distinct groups- Self report and structured interviews, diaries, electronic monitoring, prescription refill history and biochemical assays [1].
Disappointingly, of the 10 adherence measurements used in these studies, electronic monitoring was used in only two, with self- report used 4 times and prescription refill 4 times.
Self-report has been shown to vastly over-estimate adherence when compared to more objective measures, due to inaccurate recall and social desirability bias. In this journal in 2009, Otsuki and colleagues showed that in a group of inner city children with asthma, baseline self- reported adherence to inhaled steroids was 85%, compared to 25% from canister refill data[2].
Four of the studies used prescription refill as an adherence assessment tool. This is a more objective measure, but has also been shown to over-estimate adherence, as there is no guarantee dispensed medication is taken. In a Brazilian study, refill data showed a mean adherence of 70%, compared with only 52% when measured with electronic monitors[3].
Electronic monitoring was used in only two of the studies but is potentially the most objective and reliable method of adherence monitoring. One of the two studies included in McGrady's meta-analysis, Mcnally et al, recorded adherence rates to fluticasone using this method as low as 23%, and showed a strong association between low adherence and increased health care utilization[4].
Dean and colleagues recently performed an excellent meta-analysis of adherence interventions in chronic childhood disease[5]. In the 17 studies analysed, electronic monitoring was again only used twice, and they concluded education interventions alone are insufficient to improve adherence. The lack of objective monitoring in the majority of these studies has potentially skewed the results towards the null hypothesis and led to these conclusions.
Objective and reliable adherence monitoring in future studies is essential in order to find effective adherence interventions for the pediatric population. Whilst objective, biochemical assays are not a feasible measure outside the research setting, which leaves electronic monitoring as the gold standard.
McGrady and colleagues have shown us in this article the huge financial burden of poor adherence in pediatric chronic illness. If we are to find effective interventions to this significant problem, researchers should strive to use objective adherence measurements in future studies.
1. Quittner, A.L., et al., Evidence-based assessment of adherence to medical treatments in pediatric psychology. J Pediatr Psychol, 2008. 33(9): p. 916-36; discussion 937-8. 2. Otsuki, M., et al., Adherence feedback to improve asthma outcomes among inner-city children: a randomized trial. Pediatrics, 2009. 124(6): p. 1513 -21. 3. Jentzsch, N.S., et al., Monitoring adherence to beclomethasone in asthmatic children and adolescents through four different methods. Allergy, 2009. 64(10): p. 1458-62. 4. McNally, K.A., et al., Adherence to combined montelukast and fluticasone treatment in economically disadvantaged african american youth with asthma. J Asthma, 2009. 46(9): p. 921-7. 5. Dean, A.J., J. Walters, and A. Hall, A systematic review of interventions to enhance medication adherence in children and adolescents with chronic illness. Arch Dis Child, 2010. 95(9): p. 717-23.
Conflict of Interest:
None declared