August 13, 2019

expert reaction to study looking at ADHD medication and brain development in children

Research, published in the journal Radiology, reports that a drug, Methylphenidate (MHP), used in the treatment of ADHD may impact the brain development of children who take it.

Prof David Nutt, The Edmond J Safra Chair and Head of the Centre for Neuropsychopharmacology, Division of Brain Sciences, Dept of Medicine, Imperial College London, Imperial College London, said:

“This is an interesting and well conducted study with placebo controls. The impact of methylphenidate to increase FA (fractional anisotropy) maybe explains why methylphenidate is an effective treatment for ADHD and it’s a pity that they don’t present clinical outcome data in this paper in relation to this. There is evidence from other psychiatric disorders that increased FA is associated with clinical improvements¹. Why the effect should be seen in the adolescence, but not adult brain is unclear, but may reflect greater opportunity for change in the younger brain.”

1. ToMol Psychiatry. 2017 Aug;22(8):1164-1171. doi: 10.1038/mp.2016.217. Epub 2016 Dec 6. Pattern of structural brain changes in social anxiety disorder after cognitive behavioral group therapy: a longitudinal multimodal MRI study. Steiger VR1,2, Brühl AB2,3, Weidt S4, Delsignore A4, Rufer M4, Jäncke L1,5,6,7, Herwig U2, Hänggi J1.

Dr Punit Shah, Psychology lecturer, University of Bath, said:

“This is an interesting and important study, which isn’t completely novel but uses a new research design, adds to evidence showing that ADHD medication affects brain structure. However, it is important to remember that AHDH is diagnosed based on behaviour, therefore small changes in the development of brain structure are less clinically relevant than careful diagnostic procedures and research on the mental processes and behaviour associated with ADHD. Relatedly, it is also the case that brain structure is not always related to behaviour in a clear-cut way, so behavioural changes as a result of medication are, in my view, more interesting than changes in the brain.

“Notwithstanding these limitations of the study, I agree with the authors sentiments about the (over)prescribing of medication for ADHD and related neurodevelopmental conditions. This is a bigger issue in the US than the UK, but there is growing use of these pharmacological agents in children and young adults across the world. Indeed, ADHD medications are also inappropriately being used by university students, whose brains are also still developing, to boost their academic performance. It is possible that similar changes to brain structure identified by the authors, are also being driven by the misuse of Methylphenidate in this population. This warrants investigation in future research.”

‘White Matter by Diffusion MRI Following Methylphenidate Treatment: A Randomized Control Trial in Males with Attention-Deficit/Hyperactivity Disorder.’ by Reneman et al. was published in Radiology at 15:00 UK time on Tuesday 13 August. 

Declared interests:

Prof David Nutt: “has advised several companies with an interest in ADHD treatments”

Dr Punit Shah: “None”