EFFECT OF FRENCH MARITIME PINE BARK EXTRACT ON ATTENTION-DEFICIT HYPERACTIVITY DISORDER: A RANDOMIZED CLINICAL TRIAL.

This is a dataset from a phase III, randomised, double-blind, placebo and active product controlled, multicentre clinical trial with three parallel treatment arms to compare effects on ADHD and ADD behaviour between Pycnogenol®, MPH (Medikinet® Retard) and placebo, using the ADHDRating Scale (ADHD-RS/ARS) as a primary outcome measure.

Evaluations were performed in weeks 5 and 10, as compared to baseline. Two visits with similar evaluations were conducted: at baseline and after 10 weeks. Next to baseline and final evaluations, an extra evaluation of behaviour and physical symptoms was conducted in week 5 by means of questionnaires. The trial population will consists of ADHD and ADD patients recruited at the University Hospitals of Antwerp (UZA) and Ghent (UZ Ghent) and the Hospital Network Antwerp (ZNA), Belgium. Participants were randomised, stratified by trial centre, to one of the three treatment arms (placebo, Pycnogenol®, or Medikinet® Retard) by randomization.com randomisation software. Published protocol: Verlaet AAJ, Ceulemans B, Verhelst H, Van West D, De Bruyne T, Pieters L, Savelkoul HFJ, Hermans N. Effect of Pycnogenol® on attention-deficit hyperactivity disorder (ADHD): study protocol for a randomised controlled trial. Trials (2017), 18(1).

As the primary objective is to assess the efficacy of Pycnogenol® for improving ADHD and ADD behaviour as rated by teachers compared to placebo and Medikinet® Retard, the primary outcome is the summed ADHD score of the ADHD-RS as rated by teachers. Teachers filled out this questionnaire before the start of the intervention and after 5 and 10 weeks. Secondary outcomes ADHD/ADD behaviour Secondary outcomes related to ADHD/ADD behaviour are:

Summed ADHD score of the ADHD-RS, rated by parents

Summed ADHD score of the Social-emotional Questionnaire (SEQ), rated by parents and teachers

Scores on ADHD subscales of the ADHD-RS and SEQ, rated by parents and teachers (hyperactivity, impulsivity and inattention)

Percentage of responders rated by parents and teachers, defined as participants with a reduction of at least 20% of their baseline summed ADHD-RS s

Social behaviour problems subscale of the SEQ, rated by parents and teachers, to evaluate to what extent symptoms of ODD and CD are displayed

Anxiety subscale of the SEQ, rated by parents and teachers, to evaluate symptoms of general anxiety, social anxiety and anxiety-depression

Physical and sleep complaints, including various potential side effects, measured by the Physical Complaints Questionnaire (PCQ)

Dietary habits of participants were assessed by a Food Frequency Questionnaire (FFQ).

The ADHD-RS (ARS) is a validated, internationally accepted questionnaire. Its 9 inattention (IA) and 9 hyperactivity and impulsivity (HI) items, rated on a four-point rating scale (never/seldom 0, sometimes 1, often 2, or very often 3), are based on the DSM. The ADHD-RS was used in previous trials as well. 

Besides ADHD, the Social-Emotional Questionnaire (SEQ) assesses core symptoms of other social-emotional problems (social behaviour problems, anxiety and autism). Its 72 questions are based on the DSM and rated on a five-point scale (never 0, less than once a month 1, every month 2, every week 3, or (almost) every day 4). The ADHD score can be subdivided into an hyperactivity (H) score, impulsivity (I) score and inattention (IA) score, each based on 6 questions.

The PCQ enquires physical and sleep complaints, for instance related to pain, unusual thirst/perspiration, asthma or rhinitis, skin problems, tiredness, gastrointestinal problems and sleep problems. Questions include potential adverse effects and are rated on a five-point scale. In addition to several stand-alone questions, various questions can be combined (e.g. total pain: headache, stomach ache and growing pains). Each item is rated on a five-point scale (never 0, less than once a month 1, every month 2, every week 3, or (almost) every day 4).  

The FFQ consisted of 50 questions on different food groups to be rated on a nine-point scale (never 0, less than once a month 1, 1-3 times a month 2, once a week 3, 2-4 times a week 4, 5-6 times a week 5, once a day 6, 2-3 times a day 7, more than 3 times a day 8) to assess global dietary habits (e.g. how often a participant consumes fresh fruits or vegetables).

Researchers involved in digitalizing questionnaire answers and statistics were blind for the participant groups. In case of >2 missing answers regarding a (sub)score within a patient, this (sub)score was set to missing. Participants were excluded from analyses only for those outcomes without any data available. Several teacher questionnaires were missing due to teachers never responding/not responding anymore, starting/ending the study during the summer holiday, covid-19 (homeschooling), or a combination of these.

Data in SPSS were directly used for statistics. Data in excel are raw data.