Behavioral and cognitive effects of docosahexaenoic acid in drug-naïve children with attention-deficit/hyperactivity disorder: a randomized, placebo-controlled clinical trial
This study aimed to investigate the efficacy of docosahexaenoic acid (DHA) dietary supplementation on behavior and cognition in school-aged, drug-naïve children with attention-deficit/hyperactivity disorder (ADHD). A total of 50 participants with ADHD aged 7 to 14 were enrolled in a 6-month randomized, placebo-controlled clinical trial and received either DHA or placebo. The primary outcome measure was the change in the ADHD rating scale IV Parent Version–Investigator (ADHD-RS-IV) after 4 and 6 months. Secondary outcome measures included Conners Parent Rating Scale-revised, other behavioral rating scales including quality of life and global functioning, and computerized cognitive tasks. Baseline assessment also addressed the blood fatty acids profile. No superiority of DHA supplement to placebo was observed on ADHD-RS-IV, the a priori primary outcome. DHA supplementation showed a significant, nonetheless quite small, effect on children’s psychosocial functioning, emotional problems, and focused attention. Neither major nor minor adverse events were reported throughout the trial. This study shows that 6-month DHA supplementation has no beneficial effect on the symptoms of ADHD in school-aged, drug-naïve children with an established diagnosis of ADHD. Nevertheless, the 6 months treatment with supplemental DHA appears to have small positive effects on other behavioral and cognitive difficulties, which, in light of the absence of side-effects, could be reasonably followed up in future intervention studies. (https://clinicaltrials.gov/ct2/show/NCT01796262: The Effects of DHA on Attention Deficit and Hyperactivity Disorder (DADA)).
KeywordsAttention-deficit/hyperactivity disorder (ADHD) Docosahexaenoic acid (DHA) Fatty acids Cognition Behavior
The authors are grateful to all the children and their families for participating in the study. They also acknowledge the work of Morena Achilli and all nurses at Scientific Institute, IRCCS E. Medea, Child Psychopathology Unit, for their assistance with the collection of blood; Angelo Primavera, Ausilia Rausa, Stefania Conte, Veronica La Riccia, Silvia Busti Ceccarelli, and Silvia Colonna for their research assistance.
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: this work was supported by unrestricted research grant from Dietetic Metabolic Food srl., which further provided the investigational product and respective placebo. Funders have not been involved in study design, data collection or analysis, or publication decisions.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
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