Delish Study: Diabetes Education to Lower Insulin, Sugars, and Hunger

Study Overview
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Brief Summary
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Type 2 diabetes mellitus (T2DM) is the most expensive chronic disease in the U.S. Lifestyle modification is central to T2DM management, but long-term adherence to dietary recommendations is difficult. A key challenge is the difficulty of coping with cravings for high carbohydrate or sugar-laden foods in an environment where these foods are tempting and widely available. One mechanism by which mindfulness may increase long-term dietary adherence is by better equipping individuals with skills to experience food cravings and difficult emotions without eating in response. Such approaches seek to strengthen abilities to be non-judgmentally aware of, tolerate, and respond skillfully to food cravings and difficult emotions without reacting impulsively or maladaptively. The investigators hypothesize that improved ability to manage food cravings and emotional eating is a key mechanism through which mindfulness-enhancements can improve dietary adherence. The study will test a mindfulness-based intervention (MBI) for improving dietary adherence. Although the particular diet employed is not the focus of this study, the study will use a diet with about 10% of calories from carbohydrate as: (1) it induces a low level of ketone production, which will be used as a biomarker for dietary adherence; (2) prior studies suggest it improves metabolic parameters in T2DM, including glycemic control.

Detailed Description
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The study will use ecological momentary assessment (EMA) methods to measure eating in response to difficult emotions and/or food cravings. In the R61 phase, the team will ensure this measure is appropriate for further testing and assess the impact of the MBI components on our hypothesized behavioral mechanisms in N=60 persons with T2DM. The study plans 3 waves of 20 persons each with 12 weekly sessions. All participants will attend an in-person group course providing education on basic behavioral strategies for diet and physical activity. Participants will be randomized to receive this education alone (Ed) or this same material with added MBI components (Ed+MBI). The team will also pilot test two levels of intensity of maintenance phase intervention (monthly group meetings alone or supplemented by individualized attention) to prepare them for R33 testing. the investigators plan an R33 phase trial in which 120 persons with T2DM will be randomized (using a 1:2 ratio) to Ed or Ed+MBI conditions and followed for 12 months, including a 9-month maintenance phase. The study will test the robustness of the effect of MBI components on our proposed behavioral mechanisms, and on dietary adherence, as well as preliminary effect sizes on weight and glycemic control. The study will use an innovative adaptive intervention design to optimize maintenance phase intensity, which the investigators believe may be key to augment the MBI effects. The R33 phase will be registered and reported in a separate clinicaltrials.gov record.

Official Title
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Optimizing Lifestyle Interventions With Mindfulness-based Strategies in Type 2 Diabetes

Conditions
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Diabetes Mellitus, Type 2

Intervention / Treatment
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* Behavioral: Carbohydrate-restricted diet
* Behavioral: Mindfulness


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: History of T2DM mellitus. If taking insulin, screening labs will include C-Peptide to rule out T1DM. HbA1c >= 6.5% and < 12.0% at screening. Experience food-related cravings most days of the week and eat in response to these cravings regularly. Aged 18 years old and older. Able to engage in light physical activity. Willing and able to participate in the interventions. Must be interested in following a carbohydrate- restricted diet, willing to learn about mindful eating and behavioral strategies for following prescribed diets, have sufficient control over their food intake so that they can follow either diet, and otherwise be able and willing to participate in the intervention. Intervention content must be practiced to evaluate whether it is effective. Have smartphone and are willing to use it on a regular basis for data collection. Ability to speak English. Exclusion Criteria: Unable to provide informed consent. A substance abuse, mental health, or medical condition that, in the opinion of investigators, will make it difficult for the potential participant to participate in the intervention or that may need immediate changes in medical management that will affect study outcome measures. Such conditions may include cancer, liver failure, renal failure, untreated hypo or hyperthyroidism, or history of serious bulimia. Some other serious medical conditions that may alter key study outcomes or require other important diet modifications, including untreated hypothyroidism, renal failure, cirrhosis, and conditions requiring oral or parenteral glucocorticoid treatment. Pregnant or planning to get pregnant in the next 6 months, breastfeeding or less than 6 months post-partum. Current use of weight loss medications, such as Alli or amphetamine-based drugs that may affect weight. Planned weight-loss (bariatric) surgery or bariatric surgery within the past 18 months. Currently enrolled in a weight loss program, such as Weight Watchers or a self-help group such as Overeaters Anonymous, or have unalterable plans to enroll in one of these programs in the next year. Vegan or vegetarian. Unwilling to do home ketone monitoring.

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
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Diet Education<br>All participants will receive instruction in the carbohydrate-restricted diet (CR).The study diet has approximately 10% of kcal coming from carbohydrate, typically 50 grams/day or fewer, not including fiber. Participants will be encouraged to eat a normal amount of protein, typically about 80-100 grams/day (about 20-25% of calories), and the rest of their calories from fat. Foods that are encouraged include green leafy and other non-starchy vegetables, nuts, seeds, oils (especially olive oil), fish, poultry, tofu, and avocados. Other foods consistent with the diet include berries (in modest amounts), meats, eggs, and cheese. Key foods to minimize include any sugar-sweetened foods or beverages, bread, pasta, potatoes, highly processed packaged foods, and other starchy foods. | Behavioral: Carbohydrate-restricted diet<br>* Education for carbohydrate-restricted diet<br>|
| Experimental: Diet Education + Mindfulness<br>In addition to the carbohydrate-restricted diet described above, the Ed+MBI group will receive mindfulness training consisting of two integrated components: 1) use of a mindful eating app at home to learn and practice mindfulness skills for food-cravings and eating, and 2) in-person group-based meetings to discuss and troubleshoot how the mindfulness practices are working. Key mindfulness content includes helping people improve their relationship with food and control food cravings and using mindful eating approaches including paying attention, noticing habit loops, understanding brain science and food/sugar addiction, disrupting emotional and stress eating, cultivating acceptance and curiosity, lovingkindness, detaching from thoughts, using healthy restraint, and maintaining motivation. | Behavioral: Carbohydrate-restricted diet<br>* Education for carbohydrate-restricted diet<br>Behavioral: Mindfulness<br>* Mindful eating app-use and instruction<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| frequency of eating in response to cravings (primary mechanistic outcome) | frequency (times/day) of eating in response to cravings using ecological momentary assessment (EMA) | change from baseline to 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| decreased impulsivity as measured by delayed discounting (secondary mechanistic outcome) | change in delayed discounting score | change from baseline to 6 months | 
| emotion-related eating (secondary mechanistic outcome) | measured by the coping subscale of the Palatable Eating Motives Scale (PEMS) | change from baseline to 6 months | 
| stress-related eating (secondary mechanistic outcome) | measured by two questions about stress-related eating from the MIDUS study and one additional stress-related eating question | change from baseline to 6 months | 
| resumption of dietary adherence after dietary non-adherence occurs (secondary mechanistic outcome) | time from a ketone measure of < 0.3 mmol/L to higher levels of >= 0.3 mmol/L, indicating a return to nutritional ketosis after a period of consuming foods that depress ketosis. | 6 months | 
| Glycemic control, using HbA1c (secondary clinical outcome) | hemoglobin A1c (HbA1c) | change from baseline to 6 months | 
| Fasting glucose (secondary clinical outcome) | plasma fasting glucose | change from baseline to 6 months | 
| insulin resistance(secondary clinical outcome) | Homeostatic model assessment (HOMA) index of insulin resistance (computed from insulin and fasting glucose measures) | change from baseline to 6 months | 
| Weight change(secondary clinical outcome) | pounds | change from baseline to 6 months | 
| Adherence to diet (secondary clinical outcome) | measured by blood ketones | 6 months | 
| Adherence to diet (secondary clinical outcome) | measured by 24-hour diet recall | change from baseline to 6 months | 
| Perceived Stress (secondary mechanistic outcome) | Perceived Stress Scale total score | change from baseline to 6 months |