Behavioral Economics and Self-Determination Theory to Change Diabetes Risk (BEST Change)

University of Michigan380 enrolled

Overview

Patients with prediabetes can significantly reduce their risk of developing type 2 diabetes mellitus (T2DM) by participating in a Diabetes Prevention Program (DPP) or using metformin, but very few patients with prediabetes engage in these strategies. This randomized controlled trial will compare, among adults with prediabetes, the effectiveness of financial incentives, tailored messages based on self-determination theory (SDT) principles, and the combination of financial incentives plus tailored messages based on SDT principles in decreasing hemoglobin A1c (HbA1c) and weight and in increasing participation in a DPP or use of metformin. Our main hypotheses are that the mean decrease in HbA1c will be greater in the arm that receives a combination of financial incentives plus tailored messages than in the arm that receives generic health education messages, and that the mean decrease in HbA1c will be greater in the arm that receives a combination of financial incentives plus tailored messages than in the arm that receives financial incentives alone and the arm that receives tailored messages alone. The study will also identify moderators and mediators of the effectiveness of the interventions and evaluate facilitators of and barriers to scalability, acceptability, and sustainability of the different interventions.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

DOUBLE

Enrollment

380

Conditions

Pre Diabetes

Automated educational text messagesBEHAVIORAL

During the first two weeks, participants receive a series of educational messages delivered via text message. These messages welcome participants to the study, set expectations for the next 12 months, and establish a general level of knowledge among all participants on prediabetes, the Diabetes Prevention Program (DPP), and metformin. For the next 11.5 months, participants receive three automated text messages per week that provide evidence-based educational content about prediabetes and tips on prevention. Additionally, participants receive monthly messages reminding them about their health insurance plan's coverage of the DPP at no cost and coverage of metformin as a low co-pay medication, and monthly messages providing feedback on their participation in the DPP and use of metformin in the previous calendar month. Participants' PCPs receive quarterly chart updates about participation in the DPP and use of metformin, and A1c results at enrollment and 6 and 12 months.

Autonomy-supportive automated educational text messagesBEHAVIORAL

Participants receive the same text messages as in the automated educational text message intervention, but the thrice weekly messages have been modified, where applicable, to support the participant's autonomy, in accordance with principles of Self-Determination Theory. Participants' PCPs receive quarterly chart updates about participation in the DPP and use of metformin, and A1c results at enrollment and 6 and 12 months.

Financial incentivesBEHAVIORAL

Participants in this arm have the opportunity to earn a financial incentive ranging from $50 to $250 per month for taking an evidence-based action to prevent T2DM (i.e., engagement in a DPP or fill of a metformin prescription) in the previous month.

Tailored text messagesBEHAVIORAL

Participants receive twice-weekly tailored text messages that link evidence-based actions to prevent T2DM to the participant's self-identified top values, roles, and strengths. Text messages are also tailored, when possible, to participants' self-reported importance of taking action to try to prevent T2DM (i.e., participating in the DPP or taking metformin), confidence in being able to take such preventive action, and past preventive actions taken.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Primary Care Provider part of Michigan Medicine * Body mass index (BMI) of 25 or higher (23 or higher if of Asian descent) * Primary health insurance is U-M Premier Care * Recent Hgb (hemoglobin) A1c 5.7 - 6.4% (inclusive) Exclusion Criteria: * Participated in pretesting of intervention materials * Diagnosis of type 2 Diabetes Mellitus * Serious mental health conditions (described by protocol) * End stage renal disease (described by protocol) * Alcohol dependence and opioid dependence (described by protocol) * Unable to send and receive several text messages weekly * No regular access to a smart phone or tablet with data capabilities or Wireless Fidelity (WiFi) connection at home * Currently taking metformin * Unable to take metformin due to contraindications or side effects * Participated in a Diabetes Prevention Program covered by University of Michigan Premier Care insurance * Currently enrolled in an interventional research study that is examining how a diet, program, or drug might: promote physical exercise, healthy eating habits, or weight loss; lower blood pressure; or lower blood sugar * Not planning to live in local area over the next year * Pregnant or planning a pregnancy in the next year * Received treatment for an eating disorder (e.g. anorexia or bulimia), not including binge-eating disorder, in last 12 months * Intensive cancer treatment such as bone marrow transplant, chemotherapy, radiation, or cancer related surgery (not including hormonal chemotherapy like Tamoxifen) in last six months or near future * Organ transplant in last six months * Bariatric/ gastric bypass surgery, gastric sleeve surgery, or gastric balloon procedure in last six months * Stroke, heart attack, heart surgery, or hospitalization for congestive heart failure in the past three months * Other serious health issues or personal concerns that could prevent participant from completing study

Outcomes

Primary Outcomes

Change in Hemoglobin A1c From Baseline to 6 Months

Hemoglobin A1C will be tested at a clinical lab using blood samples from venipuncture. An A1C test measures the percentage of red blood cells with glucose-coated hemoglobin. This percentage indicates average blood sugar levels over the last 2-3 months. Higher percentages indicate higher blood sugar levels, and an A1c between 5.7% and 6.4% is considered in the prediabetes range. The negative numbers for change over time indicate an improvement because they show a drop in percentages from the baseline percentages. Changes in HbA1c will be calculated by subtracting the baseline value from the 6-month value, with a negative value indicating an HbA1c reduction.

Time frame: baseline to 6 months

Change in Hemoglobin A1c From Baseline to 12 Months

Hemoglobin A1C will be tested at a clinical lab using blood samples from venipuncture. An A1C test measures the percentage of red blood cells with glucose-coated hemoglobin. This percentage indicates average blood sugar levels over the last 2-3 months. Higher percentages indicate higher blood sugar levels, and an A1c between 5.7% and 6.4% is considered in the prediabetes range. The negative numbers for change over time indicate an improvement because they show a drop in percentages from the baseline percentages. Changes in HbA1c will be calculated by subtracting the baseline value from the 12-month value, with a negative value indicating an HbA1c reduction.

Time frame: baseline to 12 months

Secondary Outcomes

Change in Weight From Baseline to 6 Months

Participants will measure their body weight (in pounds) using a scale shipped to them by the study. Participants will submit a photo of the weight displayed on the scale. Change in weight will be calculated by subtracting the baseline value from the 6-month value, with a negative value indicating a weight reduction.

Time frame: baseline to 6 months

Change in Weight From Baseline to 12 Months

Participants will measure their body weight (in pounds) using a scale shipped to them by the study. Participants will submit a photo of the weight displayed on the scale. Change in weight will be calculated by subtracting the baseline value from the 12-month value, with a negative value indicating a weight reduction.

Time frame: baseline to 12 months

Engagement in Diabetes Prevention Program or Use of Metformin

Monthly activity of participants enrolled in an online Diabetes Prevention Program (DPP) will be obtained from the program provider. Prescription fills of metformin will be collected from pharmacy benefits data, and proportion days covered (PDC) will be calculated for each month. For months 2-12 a participant is in the study, they will be considered engaged if the calculated metformin PDC for that month was 80% or higher or if they reached the monthly threshold for DPP engagement (4 lessons completed plus at least two of following for at least 4 days: tracked food intake, weighed themselves, and tracked physical activity). Total number of months engaged will be calculated for each participant. Engagement is not assessed in the first month of the study to allow for time to commence engagement.

Time frame: Months 2-12 of participation in the study