Adherence to pharmacological treatments that are effective will result in symptom reduction and improvement in functioning and participation. There are barriers and facilitators to treatment adherence that should be addressed to ensure that treatment is effective in people with ADHD.
NICE conducted a qualitative evidence review which included several important themes linked to adherence to pharmacological approaches (NICE, 2018). The review found that, as young people became older, some noted an increasing realisation that medication was effective, resulting in increased adherence with age. Adherence was increased when people with ADHD or their parents perceived it to be improving their symptoms. Adherence to medication is impacted by the level of side effects experienced by people with ADHD. Some young people with ADHD experienced a loss of ‘sense of self’ from medication resulting in reduced adherence.
Adherence to medication treatment can be negatively impacted by forgetting to take medication and difficulties with time management regarding keeping appointments for medication reviews. Adults noted difficulties accessing medication related to pharmacists being unwilling to dispense repeat prescriptions and finding GPs willing to prescribe ADHD medication. The transition from child to adult services could also result in reduced adherence due to delays in accessing adult services resulting in periods of treatment cessation (NICE, 2018).
In addition to the NICE evidence review, 4 new studies were identified that reviewed qualitative evidence about the factors that people with ADHD believe affect their adherence. The 4 studies reported here reviewed parent training programs and the use of technology to support medication adherence with positive findings. However, the studies did not have sufficiently similar outcome measures for adherence or ADHD symptoms to warrant pooling of data.
A cluster RCT (Bai, Wang, Yang, & Niu, 2015) with low risk of bias, despite a small sample size, compared parent training with a waitlist over 3 months. It reported statistically significant benefits of parent training for measures of adherence to medication and ADHD symptoms. Another cluster RCT (Zheng et al., 2020) comparing parent and teacher training with control (no further information) for 4 weeks (high risk of bias due to many instances of reporting bias) reported statistically significant benefits of parent and teacher training for medication adherence, based on parent report and medical records. An observational study with a high risk of bias (Fried et al., 2020), which used electronic medical record data to compare a text messaging intervention with treatment as usual, reported a statistically significant higher medication adherence rate in the intervention group of unclear duration.
An RCT (Weisman et al., 2018) with high risk of bias and small sample size compared an interactive, information and medication reminder app intervention with treatment as usual over 8 weeks. The study reported statistically significant benefits of the app over treatment as usual for adherence measured by pill counts and ADHD symptoms by the Clinician Rating Scale. There were no statistically significant differences for ADHD-RS (rater unclear) and for Clinical Global Impression scale – Severity and Improvement.
Clinical practice points and consensus recommendations were based on the evidence review, the GDG’s expertise and clinical experience, and adaptation of the NICE recommendations to the Australian context. The evidence identified several factors that affect adherence to treatment and these were supported by the GDG’s own experience.
The evidence highlighted time management and forgetfulness as common barriers to adherence. The GDG, therefore, recommended that clinicians were aware that the symptoms of ADHD will affect people’s adherence and remembering to collect medication and organise review appointments to ensure continuous supply of prescriptions. The GDG provided examples of how clinicians might encourage people to follow strategies that support adherence.
The GDG noted from the qualitative evidence the worry that taking medication might impact on the sense of identity of the person and that the attitudes of people close to a person with ADHD can influence adherence. The GDG agreed that although it was important that children and adolescents should be encouraged to take responsibility for their own health (including taking medication), parents and carers should oversee them.
These recommendations will require clinicians to allocate more time discussing treatment adherence with people with ADHD. However, this investment is likely to improve current and ongoing treatment/support, provide a more accurate understanding of the efficacy and adverse events of any treatment tried, and lead to a higher chance of positive outcomes. The recommendations made here are generally well established in clinical practice and are therefore likely to be acceptable to stakeholders.
