An Investigation Into the Effects of a Wild Blueberry Powder and a Wild Blueberry Extract on Cognition in Older Adults
Condition: Cognitive Decline
MeSH terms: Cognitive Dysfunction
Study type: Interventional

Summary: 
      The purpose of this study is to determine whether a 6 month dietary intervention with wild
      blueberry powder and extract stabilised with L-cysteine and L-glutathione have an effect on
      cognitive performance in participants aged between 65 - 80.
    

Detailed description: 
      Interventions: A placebo and two different wild blueberry products will be used in this study
      (see Table 1). A wild blueberry powder at two different doses and a single wild blueberry
      extract. The wild blueberry powder will be used at a 450 mg-dose, to which 45 mg of
      L-Cysteine and 5 mg of L-Glutathione will be added (wild blueberry powder-450), as well as at
      a 900 mg-dose, to which 90 mg of L-Cysteine and 10 mg of L-Glutathione will also be added
      (wild blueberry powder-900). The wild blueberry extract will consist of 100 mg of wild
      blueberry extract supplemented with 10 mg of L-Cysteine and 1 mg of L-Glutathione.
      Participants will be asked to consume two capsules daily with their normal breakfast. The
      capsules will be packed in blister packs with 4 capsules per blister. Each box contains 4
      blisters (or a total of 16 capsules) in order to provide for 1 week of study medication, with
      2 capsules remaining. Participants will be instructed to return the left-over investigational
      product weekly (i.e two capsules) using stamped addressed envelopes supplied by the
      experimenters. Weekly assessment of left-over investigational product will allow for
      continued compliance verification.

      Procedure: The study comprises of a telephone screen and then six visits, including a
      familiarization visit (week T-1), three test visits (week 0, 12 and 24), and two control
      visits (week 6 and 18). Participants may stop the study treatment without stating any reason
      at any time during the study. In addition, a participant will be withdrawn from the study if:
      a subject requests discontinuation, he/she exhibits a serious adverse event to any component
      of the test product, the participant significantly violates the inclusion or exclusion
      criteria, an intercurrent illness emerges and/or the investigator's opinion is that
      withdrawal is appropriate and in the best interest of the participant. If a participant
      withdraws from the study, he/she will be encouraged to make a final visit as soon as
      possible, irrespective of the reason for withdrawal, to complete a final battery of cognitive
      tasks.

        1. Screening: once a participant has indicated that they wish to join the trial they will
           be contacted by telephone for a brief screening session. The research associate (RA)
           will give a brief overview of the study and will ascertain that each interested
           volunteer is willing to participate for the entire duration of the study and to check
           that they fulfill our inclusion/exclusion criteria. Once confirmation of suitability for
           the study is confirmed, the RA will schedule their familiarization visit.

        2. Familiarization Visit: Volunteers will be asked to attend the Nutritional Psychology
           Unit at the University of Reading where they will receive a detailed explanation on the
           study by the participating research associate and will be asked to sign the informed
           consent form before any study procedure starts. A log will be kept identifying all
           participants having signed the informed consent form (ICF) and the participant will be
           allocated a participant number. Once consent has been given, the inclusion/exclusion
           criteria will be checked once again and vital signs (blood pressure and heart rate) and
           anthropometric measurements (height, weight, BMI) will be taken. The participants will
           then be asked to complete a number of questionnaires and cognitive tasks comprising: (i)
           Yale Physical Activity Questionnaire; (ii) Frequency of Forgetting Questionnaire to give
           a baseline assessment of their memory performance; and (iii) Computerized Global
           Cognitive Health Assessments (NART, CERAD, MMSE, letter and category fluency; unless as
           a member of the Older Adult Panel these data have been collected from them in the
           preceding 3 months). Finally, participants will be given training on the cognitive test
           battery (tasks outlined below) that will be used during the study to reduce the chances
           of 'practice' adversely effecting performance on subsequent test days. Before leaving
           the laboratory, participants will be asked to keep a 72 hour food diary (consisting of 2
           week days & 1 weekend day) so that background flavonoid intakes can be measured prior to
           the start of the intervention.

        3. Test Visits (Weeks 0, 12 and 24): All of these sessions will be held in the morning
           (typically 8am-10am arrival time to suit participants individual needs). Participants
           will attend the laboratory in a fasted state and on arrival at the laboratory we will
           check participants still fulfill our inclusion/exclusion criteria, their general
           well-being, notification of any adverse events, any issues with compliance, and to check
           whether there have been changes to any concomitant medication. Blood pressure and heart
           rate will also be measured, and the food diary will be collected (week 0 and 24 only).
           They will then receive a standard low-flavonoid breakfast and will complete the battery
           of cognitive tasks (see below). Subjects will then be given their intervention
           (sufficient quantity until their next test session, in blister packs, weeks 0 and 12
           only), and will then be requested to consume 2 capsules each day. At week 24 only, the
           Yale Physical Activity and Frequency of Forgetting questionnaires will also be
           administered, and weight will be measured.

        4. Control Visits (weeks 6 & 18): These sessions can take place at any time of day to suit
           the participant. Participants will attend the laboratory at the University of Reading to
           collect the next 6 week supply of their intervention. During these visits we will check
           that participants still fulfill our inclusion/exclusion criteria, informally check their
           well-being, inquire whether there have been any adverse events, and confirm that there
           have not been any changes to their concomitant medication. At week 18 only participants
           will be given another copy of the 72 hour food diary (consisting of 2 week days & 1
           weekend day and asked to complete this before they return for their test visit in week
           24.
    

Intervention name(s): Placebo; Wild Blueberry Powder - 450mg; Wild Blueberry Powder - 900 mg; Wild Blueberry extract 100mg
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): Formulation containing inert artificially colored maltodextrin, once daily, in a 2-hard capsule regimen; Formulation containing 225 mg wild blueberry powder + 22.5 mg L-Cysteine @ 2.5 mg L-Glutathione 250 mg placebo powder, once daily, in a 2-hard capsule regimen; Formulation containing 450 mg wild blueberry powder = 45 mg L-Cysteine + 5 mg L-Glutathione once daily, in a 2-hard capsule regimen; Formulation containing 100 mg wild blueberry powder + 10 mg L-Cysteine + 1 mg L-Glutathione + 389 mg of placebo, once daily, in a 2-hard capsule regimen
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Basic Science