Guided Imagery Intervention for Obese Latino Adolescents
Condition: Obesity; Insulin Resistance; Metabolic Syndrome
MeSH terms: Metabolic Syndrome; Insulin Resistance
Study type: Interventional

Summary: 
      Guided imagery, a mind-body complementary/alternative treatment modality, offers promise to
      reduce stress and promote lifestyle behavior change to reduce diabetes and heart disease risk
      in obese Latino adolescents. The overall purpose of this study was to determine whether
      guided imagery, could reduce diabetes risk in obese Latino adolescents undergoing a lifestyle
      intervention. The specific objectives were: 1) To pilot test a new 12-week lifestyle
      intervention in obese Latino adolescents, in order to determine the effects of the mind-body
      technique of Interactive Guided ImagerySM, over and above those of healthy lifestyle
      education, on eating and physical activity behaviors, stress and stress biomarkers, and
      hormonal markers of diabetes risk; and 2) To explore the way that changes in stress produced
      by the intervention were associated with changes in hormonal markers of diabetes risk,
      particularly insulin resistance. The investigators hypothesized that participants who
      received guided imagery program in addition to the healthy lifestyle education would show
      greater improvements in insulin resistance, physical activity, dietary intake, and stress,
      than those receiving the healthy lifestyle education without the guided imagery. The
      investigators further hypothesized that reductions in stress due to the intervention would be
      associated with improvements in insulin resistance, a major hormonal marker of diabetes risk.
      For this study, obese, Latino adolescents (age 14-17) were randomized to receive either 12
      weekly sessions of the lifestyle education plus guided imagery program, or lifestyle
      education plus a digital storytelling computer program (as a control). Outcome measures were
      assessed before and after the 12-week intervention, comparing the differences between the
      intervention groups behavioral (eating and physical activity behaviors), biological (insulin
      resistance and stress hormones), and psychological (stress) outcomes.
    

Detailed description: 
      The current proposal pilot tests the investigators' guided imagery intervention in a limited
      sample of subjects in order to refine the intervention (Study 1) and then proceeds to test
      the intervention in a controlled, randomized trial (Study 2).

      Study 1: Pilot test and refinement of guided imagery program

      Specific Aim 1: To pilot, evaluate, and complete development of a guided imagery intervention
      program based on stress reduction and improving lifestyle behaviors for use with overweight
      Latino adolescents.

      Outcome Objectives: Findings from Study 1 will permit us to test the intervention via a
      controlled, randomized trial in Study 2.

      Study Design The guided imagery intervention program will be combined with a lifestyle
      education program and will be piloted, one module weekly for 12 weeks, in 8 overweight Latino
      adolescents (4 males, 4 females). Upon completion of the pilot intervention, participants
      will participate in an idea-building session about their experiences with the program, in
      order to develop ideas to add to or modify the program. Participants will discuss the
      acceptability, cultural relevance, developmental appropriateness and obstacles to efficacy
      and delivery of the program. The information from these sessions will be analyzed in order to
      improve the intervention's developmental and cultural relevance and appeal. Analyses of the
      idea-building data will be similar to analyses used for focus group data, including
      recording, transcription, and examination of the data for emergent themes. Based on
      information obtained during the pilot study and from the idea-building sessions, the program
      will be modified for the intervention study, Study 2.

      Study 2: Clinical trial of guided imagery program intervention Specific Aim 2 : To conduct a
      randomized and controlled trial to test the direct and mediated effects of adding a guided
      imagery intervention program to a lifestyle education program. Major outcomes will include
      insulin sensitivity, psychosocial measures, and dietary and physical activity behaviors.

      Hypotheses

        1. The addition of a guided imagery intervention program to a lifestyle education program
           will be more effective than the lifestyle education program alone in increasing insulin
           sensitivity (independent of body fat), improving body composition, reducing stress
           hormone (cortisol) secretion, and decreasing cardiovascular risk factors.

        2. The addition of a guided imagery intervention program will be more effective than the
           lifestyle education alone in improving health-promoting dietary and physical activity
           behaviors.

        3. The guided imagery intervention program will change behavior and physiology through
           lowering stress and through changing the meanings of dietary and physical activity
           behaviors.

      Study Design This study is a 12-week randomized, controlled clinical trial. After collection
      of baseline psychosocial, behavioral, and metabolic outcome measurements, participants will
      be randomly assigned to either "Treatment Group" with guided imagery program + lifestyle
      education (n = 20), or "Control Group" with the same lifestyle education + digital
      storytelling program to ensure equal contact time (n = 20). At the end of the 12-week
      treatment period, all baseline measures will be repeated, and differences in outcome
      variables between groups will be assessed.

      Inclusion Criteria: see below

      Exclusion Criteria: see below

      Participant Recruitment: Clinic-based recruitment, past lists of potential recruits from our
      prior studies, referrals from hospital, local health fairs, and extensive word of mouth.

      12-Week Intervention Participants will be randomized to treatment group (lifestyle program
      plus guided imagery, n=20) or control group (lifestyle program alone, n=20), stratified by
      sex in order to ensure equal numbers of girls and boys in each study group.

      Control and Treatment (guided imagery) interventions will be delivered in weekly, 1.5 hour
      sessions over a 12-week period in the late afternoon after school. Each session will begin
      with a 45-minute lifestyle education component delivered in groups of 4-8 subjects, followed
      immediately by an individual 45 minute guided imagery module for each subject in the
      Treatment Group, or an individual 45 minute Digital Storytelling module for each subject in
      the Control Group, in order to ensure equal contact time.

      The lifestyle education program curriculum consists of 12 weekly modules focused on decreased
      intake of added sugars and increased intake of whole grains and fiber in the diet, combined
      with the non-dieting philosophy of intuitive eating. Educational content relating to
      principals of healthy nutrition and physically active lifestyle contained within the proposed
      lifestyle education curriculum are fully consistent with expert committee recommendations for
      obesity intervention in adolescents.

      The guided imagery program curriculum consists of 12 weekly, one-on-one imagery modules based
      on 2 major underlying theoretical principles: 1) relaxation/stress reduction imagery; and 2)
      imagery designed to improve eating and physical activity behaviors. The protocol of each
      one-on-one imagery module will follow the standard procedures of Interactive Guided
      ImagerySM, consisting of 3 essential aspects: 1) foresight (identification of the issue to be
      addressed in imagery); 2) insight (the facilitated imagery experience itself); 3) hindsight
      (discussion and integration of the imagery experience).

      The digital storytelling program curriculum, to control for contact time with research staff,
      consists of 12 weekly 45-minute modules delivered one-on-one immediately following the
      lifestyle education class each week. Subjects will learn to create and edit their own short
      films by writing a script, gathering media (images and music), and editing the complete
      product. The subjects will be free to choose their own topic for their project, excluding
      topics relating to obesity or health behaviors.
    

Intervention name(s): Guided Imagery; Digital Storytelling
Intervention type(s): Behavioral; Behavioral
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Health Services Research
Keywords: obesity; stress; intuitive eating; guided imagery; latinos; adolescents; insulin resistance