Study identifies most effective treatments for ADHD in adults
Southampton and Oxford researchers have found that atomoxetine and a class of drug known as stimulants are the most effective treatments in the management of attention deficit hyperactivity disorder (ADHD) symptoms in adults.
A comparative review of available ADHD treatments – funded by the National Institute for Health and Care Research (NIHR) via a Research for Patient Benefit grant to Professor Samuele Cortese of the University of Southampton – provides the most comprehensive analysis to date of the effectiveness of pharmacological, psychological and neurostimulatory treatments for ADHD.
The paper, also supported by NIHR Applied Research Collaboration Oxford and Thames Valley published in The Lancet Psychiatry , highlights that stimulants and atomoxetine are the only treatments with proven efficacy in reducing symptoms of ADHD in adults, as reported by both clinicians and patients.
The landmark study sets a new benchmark for evidence-based treatment recommendations for healthcare providers and policymakers and paves the way for future advancements in ADHD care.
This review collated and analysed data from 113 randomised controlled trials involving over 14,800 participants from different countries with a diagnosis of ADHD. The study assessed the efficacy of treatments in reducing core ADHD symptoms, alongside their acceptability and safety.
Stimulants, a group of medicines that stimulate parts of the brain to improve concentration and attention, and reduce impulsive and hyperactive behaviour, include methylphenidate, lisdexamfetamine, and dexamfetamine.
The drug atomoxetine works differently to stimulants as a selective noradrenaline reuptake inhibitor (SNRI), which increases the amount of a chemical in the brain called noradrenaline which can aid concentration and help control impulses.
In the review, atomoxetine was found to be unacceptable to some participants due to common side-effects including small increase in blood pressure and heart rate, nausea, vomiting, stomach aches, trouble sleeping, dizziness, headaches, and irritability , which highlights the importance of personalised treatment decisions, made together by clinicians with their patients.
Non-drug treatments for ADHD were also evaluated and compared to the effectiveness of commonly prescribed drugs. Clinicians reported that cognitive behavioural therapy (CBT), cognitive remediation, mindfulness, psychoeducation, and transcranial direct current stimulation, a procedure which involves electrical stimulation of the brain by applying a weak direct current on the scalp, showed some efficacy in reducing symptoms. However, this evidence was found only on clinician-reported measures, not when symptom severity was rated by the patients themselves.
Unfortunately, only a small subgroup of studies assessed the effects of interventions for adults with ADHD beyond 12 weeks, so long term information is limited.
NIHR Research Professor at the University of Southampton, Samuele Cortese, who is a senior co-author on the study, says: "There is significant variation in the way ADHD in adults is managed worldwide. Our study represents the most comprehensive evidence synthesis on the treatments for ADHD and should inform future guidelines. This can contribute to more evidence-based and standardised approaches to care, supporting adults with ADHD."
Lead researcher Dr Edoardo G Ostinelli, Senior Researcher & Deputy Lead of the Oxford Precision Psychiatry Lab (OxPPL) at the University of Oxford, and Honorary Consultant Psychiatrist at Oxford Health NHS Foundation Trust commented: “Given the concerns around the safety of ADHD medications, there is a pressing need to better understand the comparative benefits and harms of medications and non-pharmacological interventions for the management of ADHD in adults.
“This network meta-analysis is a pivotal step toward optimising ADHD treatment strategies in adults. By providing a comparative evaluation of pharmacological and non-pharmacological options, it lays the groundwork for more informed, patient-centred care.”
The study’s senior co-author Professor Andrea Cipriani, Professor of Psychiatry at the University of Oxford and Director of the OxPPL and the NIHR Oxford Health Clinical Research Facility (OH CRF) said: “This study was co-developed with people with lived experience of ADHD. While stimulants and atomoxetine have demonstrated short-term benefits, it is vital to explore sustainable treatment options and their effects on co-occurring conditions and overall well-being.
“This research fills critical gaps in understanding the comparative benefits of pharmacological versus non-pharmacological therapies for ADHD in adults but evidence for the medium and long-term efficacy of all treatments, particularly non-pharmacological options, remains limited.”
ADHD is the most common neurodevelopmental disorder, affecting around 5 percent of school-aged children (ages 6–18 years) worldwide. Symptoms persist into adulthood in up to 75 percent of people with ADHD, with an estimated global prevalence of ADHD in adults at around 2-5 percent in 2020.