A Remotely Delivered Episodic Future Thinking Intervention to Improve Management of Type 2 Diabetes

Study Overview
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Brief Summary
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The goals of this project are to assess the efficacy of remotely delivered episodic future thinking for reducing delay discounting and improving management of type 2 diabetes, including glycemic control, weight loss, medication adherence, dietary intake, physical activity, and blood pressure. This will be accomplished by randomly assigning participants (N = 64) to episodic future thinking or control thinking groups, while tracking outcome measures before, during, and after the 4-month intervention, as well at a 6-month follow-up visit. Participants in both groups will also receive access to an information-based weight loss intervention.

Detailed Description
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Participants (N = 64) will be randomly assigned to either an episodic future thinking group or control thinking groups. Participants will generate episodic future events or control information, as well as related text-based cues, and will be prompted via smartphone or web application to engage in episodic future or control thinking frequently in their natural environment (e.g., at home or work, before meal times, and in high-risk situations) for a 4-month period. Participants in both groups will be provided with one-on-one, phone-based case management and provided with instructional materials and behavioral tools for weight loss and diabetes management. Instructional materials will include: 1) a modified version of the Traffic Light Diet, which utilizes red, yellow, and green labels for food to guide participants toward the goal of consuming low energy dense, low glycemic, high nutrient dense foods; 2) the Traffic Light Activity Program, which also utilizes red, yellow, and green labels for different levels of caloric expenditure, and 3) tools for self-monitoring of weight, diet, and/or physical activity. Participants will complete four laboratory-based assessment sessions in which the investigators assess body weight, height, waist and hip circumference, glycemic control (HbA1C), adherence to oral glucose-lowering medication, delay discounting, reinforcing efficacy of food, and blood pressure. These assessments will be completed before the intervention (Week 0), during the intervention (8 weeks), and immediately after the intervention (Week 16), as well after a 2-month post-intervention follow-up (Week 24). The latter three assessments sessions will also include questions to measure participants' perceived effectiveness and ease of use of the intervention. Participants will also complete several remote assessments, including dietary intake and physical activity (during Weeks 0, 8, and 16; via accelerometer), as well as delay discounting and reinforcing efficacy of food (during Weeks 3, 8, and 16).

Official Title
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A Remotely Delivered Episodic Future Thinking Intervention to Improve Management of Type 2 Diabetes

Conditions
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Type 2 Diabetes

Intervention / Treatment
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* Behavioral: Episodic future thinking
* Behavioral: Control Thinking


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Overweight or obese (BMI of 25 or greater) Poorly controlled type 2 diabetes (HbA1C of 8% or greater) Prescribed or recommended oral glucose-lowering medication Exclusion Criteria: Current insulin therapy for type 2 diabetes History of gestational diabetes Pregnant or lactating Not ambulatory Intellectual impairment Unmanaged medical or psychiatric disorder Abnormal glucose related to medications (e.g, glucocorticoids)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Participants will engage in episodic future or control thinking in the natural environment. All participants will also receive case management regarding the Traffic Light Diet, modified for type 2 diabetes to include glycemic index of foods, as well as the Traffic Light Activity Plan and other techniques to aid in weight loss (e.g., self-monitoring).
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Episodic future thinking<br>Participants will generate positive future events and related text cues that will be accessed via an electronic app to engage in episodic future thinking. | Behavioral: Episodic future thinking<br>* Participants will engage in episodic future thinking, prompted via text-based cues, when making decisions about dietary, exercise, and medication adherence choices.<br>|
| Sham Comparator: Control thinking<br>Participants will generate non-future-oriented information and related text cues that will be accessed via an electronic app to engage in control thinking.. | Behavioral: Control Thinking<br>* Participants will engage in non-future-oriented control thinking, prompted via text-based cues, when making decisions about dietary, exercise, and medication adherence choices.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in glycemic control | Glycemic control will be assessed by hemoglobin A1C (HbA1c), a standardized diagnostic measure for type 2 diabetes. | Baseline, 8 weeks, 16 weeks, and 24 weeks | 
| Change in weight | Body weight will be measured using a digital scale. | Baseline, 8 weeks, 16 weeks, and 24 weeks | 
| Change in delay discounting | Delay discounting will be assessed using computerized behavioral tasks. | Baseline, 8 weeks, 16 weeks, and 24 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in dietary intake | Dietary intake will be assessed by 24-hour food recall, using the Automated Self-Administered 24 (ASA-24) food recalls. | Baseline, 8 weeks, 16 weeks, and 24 weeks | 
| Change in medication adherence | Medication adherence to oral glucose-lowering medication (e.g., metformin) will be assessed by direct observation (pill counts) and by self-report. | Baseline, 8 weeks, 16 weeks, and 24 weeks | 
| Change in physical activity | Duration of physical activity (in minutes) will be measured using an Actigraph accelerometer | Baseline, 8 weeks, 16 weeks, and 24 weeks | 
| Change in blood pressure | Blood pressure will be measured using an automated blood pressure device. | Baseline, 8 weeks, 16 weeks, and 24 weeks | 
| Change in waist and hip circumference | Waist and hip circumference will be assessed by measuring tape. | Baseline, 8 weeks, 16 weeks, and 24 weeks |