Factors that Affect the Adherence to ADHD Medications during a Treatment Continuation Period in Children and Adolescents: A Nationwide Retrospective Cohort Study Using Korean Health Insurance Data from 2007 to 2011

Abstract

ObjectiveSeveral factors, such as male gender, older age, type of insurance, comorbid conditions, and medication type, have been associated with attention-deficit/hyperactivity disorder (ADHD) medication adherence rates, but the results have been inconsistent. We analyzed data to answer several questions: 1) How old were patients who first refilled their treatment medications used primarily for ADHD, regardless of the medication type? 2) What socio-demographic factors are associated with medication adherence? 3) What medical conditions, such as medication type and comorbid diagnosis, influence adherence?MethodsWe analyzed National Health Insurance data, which comprised continuously enrolled Korean National Medical Insurance children (6–18 years) with at least 2 ADHD prescription claims (January 2008–December 2011). The persistence of use regarding the days of continuous therapy without a 30-day gap were measured continuously and dichotomously. Adherence, using a medication possession ratio (MPR), was measured dichotomously (80% cut-off).ResultsThe cumulative incidence of index cases that initiated medication refills for ADHD treatment during the 4 year period was 0.85%. The patients who exhibited a MPR greater than 80 comprised approximately 66%. The medication type, high school age groups, physician speciality, treatment at a private clinic, and comorbid conditions were associated with medication adherence during continuous treatment using a multivariate analysis.ConclusionA better understanding of ADHD treatment patterns may lead to initiatives targeted at the improvement of treatment adherence and persistence. Other factors, including the severity, family history, costs, type of comorbidities, and switching patterns, will be analyzed in future studies.

Exploring Factors Influencing Medication Adherence From Initiation to Discontinuation in Parents and Adolescents With Attention Deficit Hyperactivity Disorder

“…19 Various studies have examined the factors that influence medication adherence in children with ADHD. [20][21][22][23][24][25][26][27] Some have also examined the parental factors that influence medication adherence in children with ADHD. 1,[28][29][30][31][32][33] However, little attempt has been made to examine adherence in view of its dynamic nature and the 3 phases according to the ABC taxonomy.…”

Examining Breaks and Resistance in Medication Adherence Among Adolescents With ADHD as Associated With School Outcomes

“…In general, children (i.e., age of 12 years and under) appear to have higher adherence rates when it comes to taking medication as compared with their adolescent counterparts (Bhang et al, 2017; Gau et al, 2008; Sanchez, Crismon, Barner, Bettinger, & Wilson, 2005). Adolescents with ADHD appear to practice more autonomy in general and with respect to taking medication as they age out of childhood (Sibley, Altszuler, et al, 2014; Sibley, Kuriyan, et al, 2014; Wehmeier, Dittmann, & Banaschewski, 2015).…”

WISC-IV Intellectual Profiles in Korean Children and Adolescents with Attention Deficit/Hyperactivity Disorder

“…About 70% of children newly diagnosed ADHD take stimulants in South Korea, and children with ADHD who receive stimulants showed increased FSIQ and all of indexes of WISC-IV. [59][60][61][62] In summary, we investigated the demographic and cognitive characteristics of children with ADHD using the K-WISC-IV, ADHD Rating Scale, and ATA. The results of this study show that working memory is impaired in children with ADHD and can be assessed with the WMI of the WISC-IV.…”