Walnuts, Long-Chain Polyunsaturated Fatty Acids and Adolescent Brain Development

NCT02590848 | Completed DMC

• 1 other identifier: CP14/00108
• Study Type: interventional
• Target: 730
• Locations: 1 country
• Sites: 1

Brief Summary

Background: Adolescence is an important period for brain development as a result of increased synaptic plasticity. Omega-3 polyunsaturated fatty acids (n-3 PUFAs) are essential nutrients for brain development and protection against oxidative stress. Walnuts have the highest n-3 PUFA concentrations of all edible plants. Objective: The investigators hypothesize that walnut intake will increase n-3 PUFA availability in the body to a level that enhances the development of the brain during adolescence. The technicians will conduct a long-term (6 months) population-based randomized controlled trial in teenagers (n=400 in each arm), and determine the effectiveness of the intervention (30 g of walnut kernels per day, \~1.5g of n-3 PUFA) in enhancing brain development. Methods: Fieldwork team will contact teenagers and families in collaboration with 20 high schools. Families will receive a basic guide on following a healthy diet in order to ensure implementation and adherence. Brain development outcomes will be measured at baseline and after the intervention. The use of computerized neuropsychological tests will provide the precision required to detect even subtle changes in brain development resulting from the nutritional intervention. Behavioral (socio-emotional) development will be assessed in order to cover a wider picture of brain development. Blood samples will be collected to measure n-3 PUFA levels before and after the intervention in a randomized subsample from both groups (control/ intervention). Linear regression models adjusted for baseline neuropsychological scores will be used to analyze the intervention effect. Implications: The outcomes of this Project are expected to be a greater understanding of the role of n-3 PUFA intake (walnut) in brain development. A major goal in public health research is to develop cost-effective health recommendations to teenagers.

Conditions

Vitamin/Nutritional Deficiency; Neurobehavioral Manifestations

Keywords

Walnut intake; Brain development; Nutritional intervention; Healthy adolescents

Outcome Measures

Primary Outcomes (7)

• N-back task

  It is a computerized test that takes approximately 25 minutes to complete. The stimulus appears in the laptop screen one by one. Children are invited to press a button in the keyboard when the stimulus is the same as the previous one in the 1-back level. In 2-back, they are required to press the button when the stimulus in the screen is the same as the one presented 2 trials back. In 3-back, they had to press when the stimulus is the same as the one presented 3 trials back. The outcome is d: d prime (d') = z (hit rate) - z (false alarm rate)

  12 months

• ANT: Attention Network Test

  A test to provide a measure of the efficiency of three different functions of attention: Alerting (the ability to produce and maintain optimal vigilance and performance during tasks), Orienting (involves shifting attention to sensory stimuli) and Executive attention (involves detecting and resolving conflict among responses, error detection and response inhibition). - Alerting (median RT for no cue - median RT for double cue) * Orienting (median RT for central cue - median RT for spatial cue) * Executive attention (in data base: conflict) (median RT for incongruent - median RT for congruent).

  12 months

• PMA-R: Primary Mental Abilities- Revised

  This test aims to asses Fluid Intelligence. This test was finally selected instead of using Trail Making Test. This latter test assesses attention function and executive function already measured by ANT and N-Back.

  12 months

• Roulettes Task

  The Roulettes Task assesses risky decision making for rewards (money gain) and punishments (money loss) separately. More specifically, this tasks assesses whether the participant adjusts is risky behavior according to the probabilities and importance of the outcome. It assesses "hot" executive functions (cognition influenced by emotion).

  12 months

• SDQ: Strengths and Difficulties Questionnaire

  Twenty-five questions, organized in five separate sub-scales, were used to assess emotional symptoms, conduct problems, hyperactivity/inattention, peer relationship problems and pro-social behavior. Each subscale was scored from 0 to 10. A Total Difficulties Score (TDS) ranging from 0 to 40 was then generated by summing the scores for all scales except the pro-social behavior scale, which is not used to evaluate mental health.

  12 months

• ADHD-DSM-IV form list: Attention Deficit Hyperactivity Disorder DSM-IV form List

  The teacher of the child has to do answer 18 questions of multiple choice in order to rate the ADHD of the child. This is a negative scale (higher scores mean more ADHD symptoms). The scores can be transformed in number of symptoms and diagnostic criterion for ADHD and Inattentive and hyperactive subtypes.

  12 months

• Blood concentration of omega-3 and omega-6 fatty acids

  Concentrations of docosahexaenoic acid, arachidonic acid, eicosapentaenoic, alpha-linolenic acid will be measured before and after the intervention. All measures will be assessed in plasma (The results will be expressed in relative amounts (% of total FAs)).

  12 months

Secondary Outcomes (4)

• Height

  12 months

• Weight

  12 months

• Blood pressure

  12 months

• Spirometry

  12 months

Study Arms (2)

Group with no intervention

NO INTERVENTION

This group will receive healthy recommendations of eating fresh fruits

Group with walnut intake

EXPERIMENTAL

This group will receive healthy recommendation of eating fresh fruits + 30 g of walnut kernels per day during 6 months.

Dietary Supplement: Walnut intake

Interventions

Walnut intake DIETARY_SUPPLEMENT

Nutritional intervention: 30g walnut kernels per day

Group with walnut intake

Eligibility Criteria

• Age: 12 Years - 15 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)

You may qualify if:

• Participants with good communication skills
• No twins and siblings included

You may not qualify if:

• Adolescents eating walnuts everyday
• Adolescents with supplements of omega-3 fatty acids
• Adolescents with allergy to walnuts

Sponsors & Collaborators

• Barcelona Institute for Global Health: lead
• Carlos III Health Institute: collaborator

Study Sites (1)

Fundació Centre de Recerca en Epidemiologia Ambiental

Barcelona, 08003, Spain

Location

Related Publications (2)

• Pinar-Marti A, Gignac F, Fernandez-Barres S, Romaguera D, Sala-Vila A, Lazaro I, Ranzani OT, Persavento C, Delgado A, Carol A, Torrent J, Gonzalez J, Roso E, Barrera-Gomez J, Lopez-Vicente M, Boucher O, Nieuwenhuijsen M, Turner MC, Burgaleta M, Canals J, Arija V, Basagana X, Ros E, Salas-Salvado J, Sunyer J, Julvez J. Effect of walnut consumption on neuropsychological development in healthy adolescents: a multi-school randomised controlled trial. EClinicalMedicine. 2023 Apr 6;59:101954. doi: 10.1016/j.eclinm.2023.101954. eCollection 2023 May.

  PMID: 37096186 DERIVED

• Julvez J, Gignac F, Fernandez-Barres S, Romaguera D, Sala-Vila A, Ranzani OT, Persavento C, Delgado A, Carol A, Torrent J, Gonzalez J, Roso E, Barrera-Gomez J, Lopez-Vicente M, Garcia-Esteban R, Boucher O, Forns J, Burgaleta M, Sebastian N, Canals J, Arija V, Basagana X, Ros E, Vendrell J, Salas-Salvado J, Sunyer J. Walnuts, Long-Chain Polyunsaturated Fatty Acids, and Adolescent Brain Development: Protocol for the Walnuts Smart Snack Dietary Intervention Trial. Front Pediatr. 2021 Jun 8;9:593847. doi: 10.3389/fped.2021.593847. eCollection 2021.

  PMID: 34169045 DERIVED

Related Links

• Project Description
• Project Description

MeSH Terms

Conditions

Malnutrition; Neurobehavioral Manifestations

Condition Hierarchy (Ancestors)

Nutrition Disorders; Nutritional and Metabolic Diseases; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Jordi Julvez Calvo, PhD

  Fundació Centre de Recerca en Epidemiologia Ambiental, Barcelona, Spain

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 19, 2015
• First Posted: October 29, 2015
• Study Start: April 1, 2016
• Primary Completion: July 30, 2017
• Study Completion: June 5, 2019
• Last Updated: June 9, 2020

Record last verified: 2019-07

Locations

ES (1)