New study investigates the effectiveness of French Maritime Pine Bark Extract on pediatric ADHD

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A recent study¹ investigated the value of using a French Maritime Pine Bark Extract (Pycnogenol) from Horphag Research (Hoboken, NJ) as a potential therapy of attention-deficit hyperactivity disorder (ADHD), compared to methylphenidate and placebo. Methylphenidate is a stimulant and first-choice medication for ADHD, but is also associated with adverse effects. In the study, 88 pediatric ADHD patients were randomized to receive placebo, Pycnogenol, or methylphenidate for ten weeks. Teachers and parents filled out various questionnaires at baseline, 5 weeks, and 10 weeks. These include the ADHD-Rating Scale, the Social-Emotional Questionnaire, the Physical Complains Questionnaire, and the Food Frequency Questionnaire.

Results showed significant differences between treatments after ten weeks with teacher-rated summed ADHD-Rating Scale scores as well as inattention and hyperactivity/impulsivity sub scores. Post-hoc analyses shows no differences between Pycnogenol and methylphenidate, however the effects of both active treatments were significantly different from placebo for total and hyperactivity/impulsivity score. Only methylphenidate saw significant differences from placebo on the inattention score. The methylphenidate group started seeing significant results as early as five weeks. Parent-rated summed ADHD-Rating Scale score and inattention sub score saw significant differences between treatments after 10 weeks, with post-hoc analyses showing that effects did not differ between the two treatment groups, but only methylphenidate’s effects significantly differed from placebo for total score, hyperactivity/impulsivity, and inattention sub scores.

ADHD scores on the Social-Emotional Questionnaire based on teacher ratings were significantly different between the three treatments only for the hyperactivity sub score, with post-hoc pairwise comparisons showing that the effects on hyperactivity score did not differ between the active treatments, but both active treatments did differ from placebo. Parent ratings found significantly different effects between the three treatments for the total, hyperactivity and inattention scores. Post-hoc analysis showed that the two active treatments differed significantly for the two sub scores, and methylphenidate differed significantly from placebo for the total and hyperactivity score.

No serious adverse events were related to the interventions, but there were significant differences between treatment groups for the frequency of nonserious adverse events reported by parents. Post-hoc analyses that there were significantly more adverse events reported for subjects in the methylphenidate group at five and ten weeks compared to Pycnogenol. Adverse events related to Pycnogenol included headache, dizziness, nausea, and diarrhea, while adverse events for methylphenidate were GI symptoms, reduced appetite, insomnia, headache, a feeling of tachycardia, sneezing, and being emotional.

Overall, teacher scores showed that the two active treatments were evenly matched after ten weeks, except for inattention, with effects taking longer for Pycnogenol. However, these delayed effects should be balanced with the fact that Pycnogenol cause fewer adverse events, explained the researchers. Among the study’s limitations was the inclusion of only 88 patents, compared to the 144 originally called for based on power calculation.

“Results of this study strengthen the evidence underlying ‘natural’ treatment options, which is highly desired by medical staff, patients and parents. These results should be confirmed by future trials involving a greater number of patients, providing more information on specific subgroups, dosing and mechanisms of action of therapeutic modalities for ADHD,” the researchers concluded.

Reference

1. Weyns AS et al. “Clinical investigation of French maritime pine bark extract on attention-deficit hyperactivity disorder as compared to methylphenidate and placebo: Part 1: Efficacy in a randomised trial.” Journal of Functional Foods, vol. 97 (2022), https://doi.org/10.1016/j.jff.2022.105246