Time Limited Eating in Adolescents (Time LEAd): a Pilot Study
Condition: Obesity, Childhood
MeSH terms: Pediatric Obesity
Study type: Interventional

Summary: 
      The investigators propose a randomized controlled trial in 90 children (age 13-21y) with
      obesity recruited from clinical programs at the Children's Hospital Los Angeles (CHLA).
      Patients will be randomized to one of three treatment groups for a 12-week intervention:
      Group 1) Low sugar and carbohydrate diet (LSC, <90 gm carbohydrate (CHO)/day, <25 gm added
      sugar/day) + blinded CGM (used to monitor adherence and glycemic outcomes without real time
      feedback). Group 2) LSC+TLE (16-hour fast/8-hour feed for 3 days per week) + blinded CGM,
      Group 3) LSC+TLE+ real time feedback via CGM (to evaluate effect of providing CGM data on
      intervention efficacy).
    

Detailed description: 
      The majority of adolescents with obesity demonstrate declining beta cell (β-cell) function
      and progressive insulin resistance over their lifetime.1 In our population of lower income
      minority teens, 1 in 3 have obesity or severe obesity and of those 30-50% go on to develop PD
      or T2D during adolescence or as young adults.1 Although diet and increased adiposity play a
      significant role in the pathogenesis of these conditions, the standard treatment model of
      intensive lifestyle modifications often result in modest decrease in BMI z-score of -0.1-0.2
      SD.2, 3 There is a paucity of trials that have examined the effect of time limited eating
      (TLE) interventions in the treatment of youth with obesity.4 Novel dietary approaches like
      time limited eating have been shown to be effective for weight loss and improved glycemic
      control in adults with obesity but have not been examined in children.5, 6 A TLE approach
      involves interspersing normal daily caloric intake with 16-hour periods of calorie
      restriction/fasting several times a week.7-9 TLE may actually be more feasible,
      non-stigmatizing, flexible and effective for adolescents than alternatives like severe
      caloric restriction because it removes the need for intensive counting of daily caloric
      intake or macronutrient content and focuses on a straightforward task of consuming food
      during a pre-specified time period.4, 10, 11 One major limitation to implementing any dietary
      intervention in pediatric populations is concern for poor adherence and difficulty in
      reliably assessing compliance. We aim to overcome these issues with the use of continuous
      glucose monitoring (CGM) to monitor and promote adherence to the intervention and thus
      improve overall efficacy. In addition, the use of CGM will provide important outcome data
      related to overall glycemic response. Finally, we will evaluate whether providing individual
      feedback based on CGM data to subjects as real time biofeedback as part of the intervention,
      enhances efficacy. We propose a randomized controlled trial in 60 children (age 14-18) with
      obesity (BMI% > 95th percentile) recruited from clinical programs at the Children's Hospital
      Los Angeles (CHLA). Patients will be randomized to one of three treatment groups for a
      12-week intervention: Group 1) Low sugar and carbohydrate diet (LSC, <90 gm carbohydrate
      (CHO)/day, <25 gm added sugar/day) + blinded CGM (used to monitor adherence and glycemic
      outcomes without real time feedback). Group 2) LSC+TLE (16-hour fast/8-hour feed for 5 days
      per week) + blinded CGM, Group 3) LSC+TLE+ real time feedback via CGM (to evaluate effect of
      providing CGM data on intervention efficacy).

      We have 3 Specific Aims:

      Aim 1. Test the efficacy of adding a TLE approach to a LSC intervention on body fat and
      weight loss (Group 2 vs. Group 1). Hypothesis 1: LSC+TLE will result in greater decrease in
      body fat and zBMI than LSC alone.

      Aim 2. Test the efficacy of LSC+TLE compared to LSC alone on reduction on glycemic response
      (CGM) and psychosocial parameters (Group 2 vs. Group 1). Hypothesis 2: TLE+LSC will result in
      a greater improvement in glucose control (FBG) and psychosocial parameters.

      Aim 3. Evaluate if CGM use is a feasible tool to determine dietary compliance to TLE type
      interventions and determine the impact of unblinded CGM on dietary intervention adherence and
      efficacy (Group 3 vs. Group 2). Hypothesis 3a: CGM will be a feasible tool to determine
      dietary compliance. Hypothesis 3b: Unblinded CGM data will result in 1) improved adherence to
      the dietary intervention as assessed by percent time in range when compared to those wearing
      a blinded CGM and 2) improve intervention effects.

      Overall Impact: This research will generate new knowledge that can readily be integrated into
      clinical weight management programs to optimize their impact and accelerate healthy changes
      for youth with obesity. This dietary intervention could lead to global improvement and result
      in slowed disease progression, decreased complications and reduced prevalence of secondary
      comorbidities that arise from a lifetime of obesity.

      Virtual Adaptation: To respond to the COVID-19 research restriction the study protocol was
      adapted for a 100% virtual model in which all study procedures, consent and outcome measures
      were collected virtually. For this cohort the aim was to recruit 10-12 completer per study
      arm with a maximum anticipated recruitment of 20-30 adolescents per group. For the virtual
      adaptation there is no DEXA scan or blood testing that is collected due to the in-person
      restriction.
    

Intervention name(s): Low sugar and carbohydrate diet; Time Limited Eating; Continuous Glucose Monitor
Intervention type(s): Behavioral; Behavioral; Device
Intervention description(s): Low sugar and carbohydrate diet (LSC, <90 gm carbohydrate (CHO)/day, <25 gm added sugar/day); 16-hour fast/8-hour feed for 3 days per week; CGM (used to monitor adherence and glycemic outcomes without real time feedback)
Other intervention name(s): LSC; TLE; CGM
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Investigator)
Primary purpose: Treatment