An Investigation of the Relationship Between Omega-3 Fatty Acid Nutrition and Mental Health in Children and Adolescents
Condition: Major Depressive Disorder; Depression; Child Mental Disorder
MeSH terms: Depression; Depressive Disorder; Depressive Disorder, Major; Mental Disorders; Neurodevelopmental Disorders
Study type: Observational

Summary: 
      This is an observational case-control add-on study to an investigator-initiated clinical
      trial (IICT) (ClinicalTrials.gov Identifier: NCT03167307): Omega-3 fatty acids as firstline
      treatment in pediatric depression. A 36-week multi-centre, double-blind, placebo-controlled
      randomized superiority study.

      This project will recruit a healthy control group matched for age and sex to a sub-group of
      patients with diagnosed pediatric major depressive disorder (pMDD) enrolled in the IICT. The
      aim is to investigate the relationship of n-3 FA intake and status with mental health in
      children and adolescents with and without diagnosed pMDD, and explore potential biochemical
      mechanisms underlying this relationship by measuring biomarkers related to n-3 FA metabolism,
      mental health and cognitive function.
    

Detailed description: 
      According to a recent school survey, one out of ten adolescents in Zurich have moderate to
      marked depressive symptoms. Early onset of paediatric major depressive disorder (pMDD) is a
      risk factor for chronic and recurrent forms of depression in adulthood (MDD). MDD is
      associated with difficulties in relationships, impaired school and work performance, and an
      increased risk of substance abuse. Furthermore, MDD is a major contributor to the burden of
      suicide and poor long-term health late in life. The emerging potential of n-3 polyunsaturated
      fatty acids (n-3 PUFAs), also known in short as omega-3 fatty acids (n-3 FAs), for the
      treatment of MDD is being investigated in several studies. Previous observational studies
      suggest a link between the consumption of n-3PUFA-rich food and the level of depressive
      symptoms. However, studies that investigated the potential beneficial effects of n-3 PUFA
      supplementation for the treatment of MDD compared with placebo showed inconsistent findings.

      Primary objectives of this project are:

        1. To determine the relationship of n-3 FA intake and status with mental health in children
           and adolescents with and without diagnosed pMDD.

        2. To explore biochemical mechanisms underlying this relationship by measuring biomarkers
           related to n-3 FA metabolism, mental health, cognitive function, and potential pathways
           linking n-3 FA intake/status and brain health (e.g. immune system, gut
           microbiome-brain-axis).

      Participants meeting the following criteria are eligible for the study:

      Inclusion criteria:

        -  Participants of female and male sex

        -  Children aged 8 to ≤ 13 years or teenagers 13 to < 18 years at time of study entry

        -  Written informed assent of the subject and written informed consent from the subject's
           parents/legal representatives

        -  No present primary diagnosed psychiatric disorder according to the M.I.N.I. KID Test

      Exclusion criteria:

        -  More than 4 weeks of regular n-3 FA supplementation

        -  Women who are self-reported pregnant or breast feeding

        -  Pre-existing neurological or medical conditions likely to be a risk factor for
           developing depressive symptoms

      In a first step participants will be screened for in- and exclusion criteria. If participants
      can be included into the study we will

        -  Measure participant's mental health with behavioural and cognitive assessments

        -  Collect biological samples from participants (blood, urine, saliva, hair, and stool)

      This study aims to recruit a total of 200 participants: 100 cases (from IICT) and 100
      controls (recruited for this study).

      There will be a total recruiting period of 18 months.
    

Observational model: Case-Control
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Children/adolescents in German speaking Switzerland
      
Biospecimen description: 
      Blood, urine, saliva, hair, and stool
    
Keywords: n-3 fatty acids; pediatric Major Depressive Disorder