The importance of achieving long-term treatment effects in ADHD

Abstract

Over the past decade, there has been a strong increase in the number of children diagnosed with Attention-Deficit/ Hyperactivity Disorder (ADHD) [1]. The prescription rates of drugs to treat ADHD were between 47.3 and 59.6% in 2014–2015 [1]. Although pharmacological treatment of ADHD appears efficacious, treating children with medication has clear limitations. These include considerable rates of non-response [7], common adverse effects such as loss of sleep and appetite [9], and very limited information on longterm safety and efficacy. This emphasizes the importance of non-pharmacological treatment of ADHD. Studies into strategies to maintain initial results of non-pharmacological treatments are scarce, however. In the current issue, Qian and colleagues from the Peking University Sixth Hospital describe results of a second dose of ecological executive skills training for children with ADHD one year after an initial training. While the first dose of this executive skills training was mostly child-focused, the second dose (or booster) also included a behavior parent training component. Compared to a waiting list, the authors found that the booster intervention led to improvements on executive functioning (planning abilities and delay aversion) as measured by the Cambridge Neuropsychological Test Automated Battery, on daily executive functioning performance as measured by the BRIEF questionnaire, and on ratings of ADHD symptoms by parents. Improvements were maintained one year after the end of the booster training. Empirical evidence for a longterm behavioral treatment strategy for ADHD is important, given the chronic nature of ADHD. Over the years, several meta-analyses have been performed on behavioral interventions for ADHD [10,11]. A recent meta-analysis [11] into the effects of socials skills training for children and adolescents with ADHD, covering 25 randomized trials with a total of 2690 participants, did not indicate statistically significant treatment effects on teacher-rated social skills, emotional competencies, or general behavior at the end of treatment, but found improvements on teacher-rated ADHD symptoms (standardized mean difference [SMD] = 0.26). The authors, however, warned against a high risk of bias, lack of clinical significance, high heterogeneity, and low certainty regarding this finding. These disappointing findings are in line with the modest effects of social skills training in children with autism spectrum disorder (e.g., [6]). Organizational skills training appears to be a more promising intervention according to the results of another meta-analysis, covering 12 studies involving 1054 children with ADHD [2]. Both teachers and parents reported statistically significant improvements on symptoms of inattention. Teachers also reported better academic performance and average grade points. Most behavioral interventions for children with ADHD have some component of parent training. Parent-mediated treatment works from the rationale that parents act as a therapist to modify the child’s behavior. Following this rationale, parental behavior should change before the child’s behavior can change [5]. Two meta-analyses on behavioral treatments, most of them with a parenting component [4, 10] will be discussed here. Both subdivide their outcomes in most proximal and probably blinded, to indicate whether the rater of the behavior was aware of the treatment allocation of the family. The meta-analysis by Daley et al. [4] focused on behavioral interventions for children and adolescents with ADHD, and not only examined child outcomes, but also included possible changes in parents. Meta-analytic evidence showed positive effects on proximally rated ADHD core symptoms (SMD = 0.35), symptoms of conduct disorder (SMD = 0.26), social skills (SMD = 0.47), and academic achievement (SMD = 0.28). Importantly, Daley and colleagues also showed improvements on positive (SMD = 0.68) and negative parenting (SMD = 0.57), and parental self-concept (SMD = 0.37). Interestingly, also a small but significant effect of behavioral interventions for ADHD on parental mental health (Effect size [ES] = 0.09) was found. Furthermore, they found that although probably blinded measures * Annabeth P. Groenman [email protected]