Effects of Lemon Verbena Extract Supplementation in Sub-ADHD Children

Not Applicable

Completed

• Conditions: Behavior, Child; Cognitive Change
• Interventions: Dietary Supplement: Placebo; Dietary Supplement: Lemon verbena

• Registration Number: NCT05476549
• Lead Sponsor: Northumbria University

Brief Summary

The aim of this study is to investigate the effects of 15 mg/kg lemon verbena, in comparison to placebo, on the attention deficit hyperactivity disorder (ADHD) type behaviour and cognitive function of children who do not have a diagnosis of ADHD, but who exhibit high scores (highest tertile) on ADHD behaviour parameters. Multiple aspects of mood will also be assessed.

The proposed randomised, double-blind, placebo-controlled, parallel groups design methodology will assess the psychological effects of 15 mg/kg lemon verbena extract and a matched placebo prior to and after 4 and 8 weeks of supplementation. The trial will utilise the COMPASS cognitive assessment system (Northumbria University) and a range of mood measures during laboratory testing visits.

Parents and children will also take part in a concomitant smartphone study, comprising the collection of the parent's assessment of the child's behaviour/cognitive function and the child's self-report of the same, plus their mood. These assessments will take place on Days -1, 14, 28, 42 and 56.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-07-25
• Study First Submitted QC: 2022-07-25
• Study First Posted: 2022-07-27
• Study Start: 2022-08-04
• Primary Completion: 2023-08-27
• Study Completion: 2023-08-27
• Status Verified: 2023-12
• Last Update Submitted: 2023-12-08
• Last Update Posted: 2023-12-11

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 140

Inclusion Criteria

• Are in good health as reported by themselves and their parent/guardian
• Are aged 8 to 17 years at the time of giving assent and parents giving consent
• Have a sex and age-related BMI less than the 98th centile according to the local NHS guidelines
• Are rated by their parents as having a high score (T score of ≥60) on both the Connors 3 subscales of Inattention and Hyperactivity/Impulsivity.
• Have no current diagnosis of ADHD
• Have no relevant food intolerances/ sensitivities/ allergies
• Are not currently using any illicit, herbal or recreational drugs including alcohol and nicotine products
• Are not currently taking prescription medications
• Have not taken dietary supplements e.g. Vitamins, omega 3 fish oils etc. in the last 4 weeks
• Do not have a diagnosed neurological condition, or learning/behavioural or neurodevelopmental differences (e.g. dyslexia, autism)
• Do not suffer from visual (including colour blindness) impairment that cannot be corrected with glasses or lenses (that may impact task performance in the opinion of the PI).
• Do not have any pre-existing diagnosed medical condition/illness which will impact taking part in the study
• Consume less than 250 mg/day of caffeine.
• Can complete all of the study assessments at the training visit
• Are not currently participating in other clinical or nutrition intervention studies, or have in the past 4 weeks
• Are compliant with regards to treatment consumption
• Have not taken antibiotics within the past 4 weeks
• Do not have any health condition that would prevent fulfilment of the study requirements (this includes non-diagnosed conditions for which no medication may be taken)

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	-
Lemon verbena	Lemon verbena	-

Primary Outcome Measures

Name	Time	Method
Change in depression-dejection from baseline to 8 weeks	Baseline to 8 weeks	Profile of mood states questionnaire
Change in systolic blood pressure from baseline to 8 weeks	Baseline to 8 weeks	Systolic blood pressure (mmHg)
Change in diastolic blood pressure from baseline to 8 weeks	Baseline to 8 weeks	Diastolic blood pressure (mmHg)
Change in heart rate during the performance of cognitive tasks from baseline to 8 weeks	Baseline to 8 weeks	Beats per minute
Change in confusion-bewilderment from baseline to 8 weeks	Baseline to 8 weeks	Profile of mood states questionnaire
Change in body temperature from baseline to 8 weeks	Baseline to 8 weeks	Degrees Celsius
Change in RMSSD during the performance of cognitive tasks from baseline to 8 weeks	Baseline to 8 weeks	Root mean square of successive differences between normal heartbeats (RMSSD)
Change in Conners 3 score from baseline to 8 weeks, parent rating	Baseline to 8 weeks
Change in heart rate variability index during the performance of cognitive tasks from baseline to 8 weeks	Baseline to 8 weeks	Heart rate variability index
Change in subjective mood from baseline to 8 weeks, alertness	Baseline to 8 weeks	Visual analogue scale composite score
Change in Conners 3 score from baseline to 8 weeks, child rating	Baseline to 8 weeks
Change in anger-hostility from baseline to 8 weeks	Baseline to 8 weeks	Profile of mood states questionnaire
Change in subjective perceived stress from baseline to 8 weeks	Baseline to 8 weeks	Perceived stress scale (PSS) total score
Change in reaction time of performance on arrow flankers task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, reaction time in milliseconds
Change in reaction time of performance on rapid visual information processing task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, reaction time in milliseconds
Change in total mood disturbance from baseline to 8 weeks	Baseline to 8 weeks	Profile of mood states questionnaire
Change in tension-anxiety from baseline to 8 weeks	Baseline to 8 weeks	Profile of mood states questionnaire
Change in vigour-activity from baseline to 8 weeks	Baseline to 8 weeks	Profile of mood states questionnaire
Change in fatigue-inertia from baseline to 8 weeks	Baseline to 8 weeks	Profile of mood states questionnaire
Change in stress index during the performance of cognitive tasks from baseline to 8 weeks	Baseline to 8 weeks	The stress index is a measure of the ratio between the parasympathetic and sympathetic tone. intervals exceeds 50 milliseconds.
Change in subjective mood from baseline to 8 weeks, stress	Baseline to 8 weeks	Visual analogue scale composite score
Change in accuracy of performance from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task composite score, %
Change in accuracy of performance on arrow flankers task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, %
Change in accuracy of performance on Corsi blocks task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, %
Change in accuracy of performance on rapid visual information processing task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, %
Change in reaction time of performance on Stroop task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, reaction time in milliseconds
Change in pNN50 during the performance of cognitive tasks from baseline to 8 weeks	Baseline to 8 weeks	pNN50 is the mean number of times per hour in which the change in consecutive normal sinus (NN) intervals exceeds 50 milliseconds.
Change in subjective anxiety from baseline to 8 weeks	Baseline to 8 weeks	State-trait anxiety inventory (STAI) total score
Change in subjective mood from baseline to 8 weeks, tranquility	Baseline to 8 weeks	Visual analogue scale composite score
Change in accuracy of performance on Stroop task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, %
Change in reaction time of performance on numeric working memory task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, reaction time in milliseconds
Change in completion time of peg and ball task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, time in milliseconds
Change in speed of performance from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task composite score, milliseconds
Change in accuracy of performance on numeric working memory task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, %
Change in accuracy of performance on peg and ball task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, number of errors
Change in false alarms on rapid visual information processing task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, number of false alarms
Change in thinking time of peg and ball task from baseline to 8 weeks	Baseline to 8 weeks	Cognitive task score, time in milliseconds

Trial Locations

Locations (1)

Brain, Performance, Nutrition Research Centre, Northumbria University; 🇬🇧 Newcastle upon Tyne, Tyne & Wear, United Kingdom