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Effects of Lemon Verbena Extract Supplementation in Sub-ADHD Children

Not Applicable
Completed
Conditions
Behavior, Child
Cognitive Change
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

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
Primary Outcome Measures
NameTimeMethod
Change in depression-dejection from baseline to 8 weeksBaseline to 8 weeks

Profile of mood states questionnaire

Change in systolic blood pressure from baseline to 8 weeksBaseline to 8 weeks

Systolic blood pressure (mmHg)

Change in diastolic blood pressure from baseline to 8 weeksBaseline to 8 weeks

Diastolic blood pressure (mmHg)

Change in heart rate during the performance of cognitive tasks from baseline to 8 weeksBaseline to 8 weeks

Beats per minute

Change in confusion-bewilderment from baseline to 8 weeksBaseline to 8 weeks

Profile of mood states questionnaire

Change in body temperature from baseline to 8 weeksBaseline to 8 weeks

Degrees Celsius

Change in RMSSD during the performance of cognitive tasks from baseline to 8 weeksBaseline to 8 weeks

Root mean square of successive differences between normal heartbeats (RMSSD)

Change in Conners 3 score from baseline to 8 weeks, parent ratingBaseline to 8 weeks
Change in heart rate variability index during the performance of cognitive tasks from baseline to 8 weeksBaseline to 8 weeks

Heart rate variability index

Change in subjective mood from baseline to 8 weeks, alertnessBaseline to 8 weeks

Visual analogue scale composite score

Change in Conners 3 score from baseline to 8 weeks, child ratingBaseline to 8 weeks
Change in anger-hostility from baseline to 8 weeksBaseline to 8 weeks

Profile of mood states questionnaire

Change in subjective perceived stress from baseline to 8 weeksBaseline to 8 weeks

Perceived stress scale (PSS) total score

Change in reaction time of performance on arrow flankers task from baseline to 8 weeksBaseline 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 weeksBaseline to 8 weeks

Cognitive task score, reaction time in milliseconds

Change in total mood disturbance from baseline to 8 weeksBaseline to 8 weeks

Profile of mood states questionnaire

Change in tension-anxiety from baseline to 8 weeksBaseline to 8 weeks

Profile of mood states questionnaire

Change in vigour-activity from baseline to 8 weeksBaseline to 8 weeks

Profile of mood states questionnaire

Change in fatigue-inertia from baseline to 8 weeksBaseline to 8 weeks

Profile of mood states questionnaire

Change in stress index during the performance of cognitive tasks from baseline to 8 weeksBaseline 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, stressBaseline to 8 weeks

Visual analogue scale composite score

Change in accuracy of performance from baseline to 8 weeksBaseline to 8 weeks

Cognitive task composite score, %

Change in accuracy of performance on arrow flankers task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, %

Change in accuracy of performance on Corsi blocks task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, %

Change in accuracy of performance on rapid visual information processing task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, %

Change in reaction time of performance on Stroop task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, reaction time in milliseconds

Change in pNN50 during the performance of cognitive tasks from baseline to 8 weeksBaseline 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 weeksBaseline to 8 weeks

State-trait anxiety inventory (STAI) total score

Change in subjective mood from baseline to 8 weeks, tranquilityBaseline to 8 weeks

Visual analogue scale composite score

Change in accuracy of performance on Stroop task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, %

Change in reaction time of performance on numeric working memory task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, reaction time in milliseconds

Change in completion time of peg and ball task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, time in milliseconds

Change in speed of performance from baseline to 8 weeksBaseline to 8 weeks

Cognitive task composite score, milliseconds

Change in accuracy of performance on numeric working memory task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, %

Change in accuracy of performance on peg and ball task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, number of errors

Change in false alarms on rapid visual information processing task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, number of false alarms

Change in thinking time of peg and ball task from baseline to 8 weeksBaseline to 8 weeks

Cognitive task score, time in milliseconds

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

Brain, Performance, Nutrition Research Centre, Northumbria University

🇬🇧

Newcastle upon Tyne, Tyne & Wear, United Kingdom

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

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