Program for the Comprehensive Neurocognitive Treatment of Excess Weight
Condition: Obesity; Overweight
MeSH terms: Overweight
Study type: Interventional

Summary: 
      The present study aims to determine the effectiveness of a comprehensive neurocognitive
      program for the treatment of excess weight. The program will include sessions to improve
      multiple cognitive processes implicated in weight gain and obesity. These cognitive processes
      include approach-avoidance bias, inhibition control, implementation intentions and episodic
      future thinking. Participants will be randomly allocated to one of three groups: 1) the
      experimental group will receive active neurocognitive sessions, 2) an active control group
      that will receive sham sessions and 3) a usual treatment control group. All three groups will
      receive a motivational interviewing session, along with personalized diet and physical
      exercise recommendations. We hypothesized that the neurocognitive program will decrease body
      mass index in people with overweight and obesity. In addition, the neurocognitive program
      will improve other anthropometric measures (waist circumference, waist-to-hip and
      waist-to-height ratios), lifestyle behaviors (eating behavior and physical activity), as well
      as cognitive processes (approach-avoidance bias, food inhibition, food liking and delay of
      gratification). Finally, the program will show its efficiency in the economic balance of
      cost-effectiveness and cost-utility.
    

Detailed description: 
      1. STARTING HYPOTHESES AND GENERAL OBJECTIVE HYPOTHESIS: The treatment of excess weight
           with a comprehensive program based on experimental knowledge about the functioning and
           modification of the impulsive and executive systems will be effective for the treatment
           of overweight and obesity. Thus, the neurocognitive training will reduce body mass index
           (BMI) in people with overweight and obesity, compared to a sham treatment and to only
           usual treatment. In addition, the neurocognitive program will improve other
           anthropometric measures (waist circumference, waist-to-hip and waist-to-height ratios),
           lifestyle behaviors (eating behavior and physical activity), as well as cognitive
           processes (approach-avoidance bias, food inhibition, food liking and delay of
           gratification). Finally, the program will show its efficiency in the economic balance of
           cost-effectiveness and cost-utility.

           GENERAL OBJECTIVE: To determine the effectiveness of a comprehensive neurocognitive
           program for the treatment of excess weight.

           1.1. Specific Aims: Objective 1: To examine the effectiveness of a comprehensive
           neurocognitive training to reduce BMI in the short, medium and long term
           (post-treatment, 3-month follow-up and 6-month follow-up).

           Objective 2: To study the effectiveness of the comprehensive neurocognitive program to
           change food behaviors, physical activity and body measures.

           Objective 3: To investigate which active ingredients have an impact on the results of
           the program as outlined below:

           3.1. To study the effectiveness of the impulsive training (approach-avoidance bias
           modification and improvement of inhibitory control) to reduce the approach bias to
           appetitive foods, increase the inhibitory control, improve the food decision making and
           modify the valuation of healthy and unhealthy foods.

           3.2. To study the effectiveness of reflexive training (implementation of intentions and
           episodic future thinking) to improve behaviors related to implementation of intentions
           in healthy eating and physical activity, and to increase delay of gratification.

           3.3. To compare the effectiveness of the neurocognitive training (impulsive and
           reflexive) to reduce BMI and body measures, and to improve food behaviors and physical
           activity.

           3.4. To study the variables related to cognition, affect, stress and non-homeostatic
           food intake, motivation and personality to predict or mediate the intervention results.

           Objective 4: To conduct an economic evaluation analysis of cost-effectiveness and
           cost-utility of the neurocognitive training in people with overweight and obesity, and
           analyze what budgetary impact would imply for the Spanish National Health System.

        2. METHODOLOGY

           2.1. Design: Randomized controlled trial of parallel groups.

           2.2. Participants: The participants (N=150) will be randomly allocated to three groups:
           experimental group (neurocognitive intervention; n=50), active control group (sham
           intervention; n=50), and control group (treatment as usual; n=50).

           A randomization (minimization) through the software Minimizer® will be performed to
           avoid imbalances between the groups in age, sex, and BMI.

           2.3. Interventions: Pre-treatment interventions (all groups): Participants will
           participate in a group Motivational Interviewing session, and will receive an
           individualized diet and a physical exercise planning for 6 weeks. Also, informative
           videos and brochures will be provided. Further, participants will participate in two
           group informative sessions (one with a nutritionist and another with a physical exercise
           instructor). These two meetings will be recorded and made available for all
           participants.

           Whatsapp groups will be created to promote participants' social interactions.

           Neurocognitive program (experimental and active control groups). Duration: 4 weekly
           sessions of about 60-90 minutes.

           Phase 1. Impulsive training will include: (i) Approach-avoidance bias modification with
           the Tilt Task app; (ii) Inhibition training with the Food Trainer task app.

           Phase 2. Reflexive training will include: (iii) Implementation of Intentions; (iv)
           Episodic Future Thinking.

           The order of phases 1 & 2 will be counterbalanced. One task will be trained in each
           session, and participants will practice that task daily at home for one week (until the
           next session). They will receive daily reminders on their mobile phones. A weekly
           pre-post assessment will be conducted for each trained task.

           Post-treatment interventions (all groups): Participants will have the opportunity to
           attend a second group meeting with the nutritionist and another with the physical
           activity professional to receive information and ask questions about how to maintain
           long-term healthy habits on diet and physical exercise. These meetings will be recorded
           and made available for all participants. They will also be provided with new videos with
           guidelines about how to maintain a healthy long-lasting eating and exercise. The aim is
           that participants be autonomous and can develop their own diet and exercise planning.

           2.4. Outcome measures: Body Mass Index will be the main outcome measure. Secondary
           outcomes will measure changes in cognitive, lifestyle behaviors and body measures.
           Mediating and moderating variables will include affect, stress and nonhomeostatic
           eating, executive functions, motivation, personality, adherence to diet and physical
           exercise, and clinical variables. Further, assessment will include screening and
           descriptive variables, and measures to calculate cost-effectiveness, cost-utility and
           budget impact of the intervention program.

        3. PROCEDURE All assessments and intervention sessions will be delivered online. Inclusion
           and exclusion criteria will be checked through the data collected in a questionnaire of
           sociodemographic and clinical variables. Further, psychopathology exclusion criteria
           will be tested with two questionnaires to measure depression, anxiety, and stress
           symptoms as well as binge eating and bulimia (DASS-21 and QEWP-5), and a short clinical
           interview by phone and/or information requested by email in those cases where there are
           doubts about any of the aspects collected through the online instruments.

      All candidates who meet the criteria will attend an information meeting about the project in
      which they will receive written and oral information, and will be asked for their informed
      consent. Then, participants will be randomly assigned to groups before the pre-treatment
      assessment sessions. The three groups of the study (intervention, active control and control)
      will complete all of the evaluations, as well as the follow-ups (see below). Further, all
      groups will received the pre-treatment interventions (Motivational Interviewing, nutrition
      and physical activity sessions). What will differentiate the groups will be, therefore, the
      treatment: neurocognitive intervention vs. sham vs. usual treatment. The control groups will
      be offered the treatment sessions (without the assessment components) after the end of the
      6-month follow-up.

      Sessions will be developed in groups of 5-6 persons. If a participant misses a session he/she
      can attend another one within 3-4 days. There will be 10 experimental groups of active
      training = 50 participants; 10 active control groups of sham training = 50 participants; and
      10 control groups = 50 participants. The program will comprise 8 weeks including three
      assessments (pre, intermedium and post-treatment), four intervention sessions, as well as
      pre-treatment and post-treatment intervention sessions. Also, two follow-up sessions at 3 and
      6 months after treatment (see below). Sessions will last about 1 hour and a half.

      Sessions will consist of the following:

        1. Informative session (session 1; week 0): All participants will be informed about the
           aims and the procedure of the research, and they will provide written informed consent.

        2. Pre-treatment assessment (session 2, week 1): All participants will complete the
           instruments to obtain the main and secondary outcomes, the potential
           mediators/moderators, and economic measures.

        3. Pre-treatment interventions (sessions 3, 4 and 5, week 2):

           3.1. Motivational interviewing session: This 90-minute session will be developed in a
           group format of 5-6 participants.

           3.2. Nutrition session: Participants will receive an individualized diet for the
           following 6 weeks. Videos and brochures about nutrition will be provided, and
           participants will assist a 60-minute group session with the nutritionist to match and
           complete relevant information on nutrition and excess weight.

           3.3. Physical activity session: Participants will receive physical activity
           recommendations for the following 6 weeks. Videos and brochures about physical exercise
           will be provided, and participants will assist a 60-minute group session with the
           physical exercise instructor to match and complete relevant information on exercise and
           excess weight.

        4. Intervention sessions (sessions 6, 7, 9 and 10; weeks 3, 4, 6 and 7): All sessions will
           start with Visual Analogue Scales to evaluate hunger, nutrition and physical activity.
           Each intervention session will be preceded by its pre-treatment evaluation, and followed
           by its post-treatment evaluation after a week of daily training. The pre and
           post-treatment evaluation of the impulsive training will be measured by the
           approach-avoidance bias (with the Tilt-Task app), food choice, the inhibitory control
           (with the Food Trainer app) and food liking. The pre and post-treatment evaluation of
           the reflexive training will be measured by the Now or Later questionnaire for the
           episodic future thinking training, and the self-registration of nutrition and physical
           exercise for the implementation of intentions.

        5. Intermediate assessment (session 8; week 5): This assessment will allow the comparison
           between the interventions for the impulsive and reflexive trainings.

        6. Post-treatment assessment (session 11, week 8): To evaluate the effectiveness of the
           whole intervention program, the measures of the pre-treatment assessment will be
           repeated.

        7. Post-treatment interventions (session 12, week 8): After the post-treatment assessment,
           participants will have the opportunity to have a second 60-minute group meeting with the
           nutritionist and another with the physical activity professional, and they will be
           provided with new 20-minute videos about how to maintain a healthy long-lasting eating
           and exercise.

           After all interventions, participants will be asked to complete a debriefing to register
           their thoughts and subjective experience about the program.

        8. Follow-up (sessions 13 and 14, week 20 and week 32): Follow-ups at 3 and 6 months after
           the intervention will include the instruments to obtain the main and secondary outcome
           measures. Besides, every month after the end of the treatment, participants will be
           contacted by email and mobile message to maintain adherence.

      Participants will be instructed to eat two hours before all evaluation (pre, intermediate and
      post-treatment, and the two follow-ups) and neurocognitive sessions. Pre, intermediate and
      post-treatment assessments will be carried out at the same hour.
    

Intervention name(s): Approach-Avoidance Bias Modification; Inhibition Training; Implementation of Intentions; Episodic Future Thinking; Sham Approach-Avoidance Bias Modification; Sham Inhibition Treatment; Setting Intentions; Recent Episodic Thinking; Motivational Interviewing; Nutritional intervention; Physical exercise intervention
Intervention type(s): Behavioral; Behavioral; Behavioral; Behavioral; Behavioral; Behavioral; Behavioral; Behavioral; Behavioral; Behavioral; Behavioral
Intervention description(s): In this task participants must zoom in or zoom out a food image according to its format (vertical or horizontal) using their smartphone device. 90% of healthy food images will appear in the format to be approached (for example, vertical), while only 10% of unhealthy images will appear in that format (to ensure concentration on the task). The format to be approached will be counterbalanced. Participants will practice the task at home at least once a day (about 5 minutes) for one week, and will receive daily reminders to practice via instant messaging on their mobile phones.; In this App participants are instructed to touch green circle items as quickly as possible, but to withhold their response and not to press on the red circle items, using their smartphone device. Some images are food, some non-foods. Participants can choose which food categories they would like to train to resist. The food-specific inhibition training condition included pictures of high-calorie foods always paired with the no-go signal. Participants will practice the task at least once a day (about 5 minutes) for one week, and will receive daily reminders to practice via instant messaging on their mobile phones.; Participants establish one intention related to food and one related to exercise, and write when, where and how they will implement each one, possible inconveniences to do it, and how they will overcome them. Furthermore, motivational cues (why I eat) will be considered (negative emotions -I'm bored; social motives -eat a piece of cake you are offered in a party; politeness/conformity with others' expectations; pleasure). The implementation of intentions related to food will be written in format: "if… then…". This format allows for the consideration of the health goals and medium and long-term objectives for each of the participants. The intention related to food will focus on unhealthy snacking habits whenever possible. Participants will read and visualized their implementation of intentions at least twice a day (about 5 minutes) for one week, and will receive two daily reminders to practice via instant messaging on their mobile phones.; Participants will decide health-related goals and anticipate positive future personal events at various time points (next month, 2-3 months and 4-6 months), from which contextual, temporal and emotional cues should be obtained. Goals and future events will be matched to generate episodic future thinking cues that include the necessary keys to facilitate their effectiveness. Participants will read and visualized their three cues at least twice a day (about 5 minutes) for one week, and will receive two daily reminders to practice via instant messaging on their mobile phones.; Participants must zoom in or zoom out a food image according to the format (vertical or horizontal) using their smartphone device. 50% of healthy food images and 50% of unhealthy food images will appear in the format to be approached (for example, vertical). The format to be approached will be counterbalanced. Participants will practice the task at least once a day (about 5 minutes) for one week, and will receive daily reminders to practice via instant messaging on their mobile phones.; In this App participants are instructed to touch green circle items as quickly as possible, but to withhold their response and not to press on the red circle items, using their smartphone devices. Some images are food, some non-foods. Participants can choose which food categories they would like to resist. High-calorie and low-calorie foods will be paired with the go signal on 50% of trials and with the no-go signal on 50% of trials. Participants will practice the task at least once a day (about 5 minutes) for one week, and will receive daily reminders to practice via instant messaging on their mobile phones.; Participants will choose 10 items of healthy foods to eat whenever they want to eat unhealthy food. They will also order a list of physical activities that they could do to lose weight. Participants will read their lists (food and exercise) at least twice a day (about 5 minutes) for one week, and will receive two daily reminders to practice via instant messaging on their mobile phones.; Participants will match habits and positive recent past events (1 day ago, 2 days ago, 1 week ago), both unrelated to food or physical activity, to establish their cues. Participants will read and visualized their three cues at least twice a day (about 5 minutes) for one week, and will receive two daily reminders to practice via instant messaging on their mobile phones.; Participants will assist a 90-minute group Motivational Interviewing session to maximize motivation and adherence to the program. The session will be guided through open questions and empathic reflections and affirmations to promote change talk. Participants will share their personal aims to reduce weight, improve their diet and increase their level of physical activity. Further, participants will talk about obstacles they have had on previous occasions, their expectations, and their motivations in regards to weight loss. When needed, information will be provided with the elicit-provide-elicit format. Sessions will end with an individual empathic summary for each participant's interventions.; Participants will maintain a 60-minute group session with a nutritionist and will watch a 20-minute video to match and complete relevant information on nutrition. The nutritionist will design a 6-week individualized diet that participants will receive after the initial assessment. When the 6-week diet ends, participants will assist another 60-minute group session with the nutritionist and will watch another video intended to teach them how to design their own healthy diet and maintain long-term healthy eating habits.; Participants will maintain a 60-minute group session with a physical exercise professional and will watch a 20-minute video to match and complete relevant information on exercise. The physical exercise professional will design a 6-week physical exercise planning that participants will receive after the initial assessment. After those 6-weeks, participants will assist another 60-minute group session with the physical exercise professional and will watch another video intended to teach them how to design their own physical activity planning and maintain long-term healthy exercise habits.
Other intervention name(s): Tilt Task; Food Trainer; Sham Tilt Task; Sham Food Trainer
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Parallel group randomized controlled trial
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Excess weight; Obesity; Overweight; Neurocognitive training