Pilot of Continuous Glucose Monitor-Augmented Food Is Medicine

Official title

Pilot of a CGM-Augmented Food Is Medicine Intervention

Overview

This study is designed to test the feasibility and preliminary efficacy of a continuous glucose monitor (CGM)-augmented food is medicine (FIM) intervention for adults with type 2 diabetes and nutrition or food insecurity. This study will learn if a FIM intervention ("intervention") that includes access to real-time CGM and nutrition counseling can increase engagement, improve glycemic management, and support healthy eating in this population, compared to the FIM intervention alone ("comparator"). At the study baseline, participants will be randomized to either the intervention or the comparator arm for 16 weeks. The intervention will occur during the first 12 weeks (phase 1: intervention phase) and will be compared to a standard FIM approach without CGM or counseling. Phase 2 (extension phase) will last 4 weeks and will consist of all participants in the intervention and comparator arm receiving both FIM and CGM for self-directed use. The study will also explore participant experiences through a series of semi-structured interviews with a subset of randomly selected participants to identify opportunities for scaling the intervention to a broader population.

Detailed description

This study is designed to test the feasibility and preliminary efficacy of a CGM-augmented FIM intervention for adults with type 2 diabetes and nutrition or food insecurity. The study will enroll adults with type 2 diabetes not using insulin/secretagogues or CGM to be randomized 1:1 to the CGM-augmented FIM intervention (intervention arm) or a standard FIM intervention (comparator arm) for 12 weeks. All participants (N=60) will wear blinded CGM for 10 to 14-days at baseline and at week 12, and complete two random 24-hour dietary recalls during each blinded CGM wear-time. Participants in the intervention arm will wear real-time CGM for the duration of the 12-week intervention and receive a series of structured counseling sessions with a registered dietician. Following the 12-week intervention, all participants will receive both FIM intervention and wear real-time CGM for a 4-week extension phase. FIM intervention will be provided in the form of electronic healthy food vouchers.

At the 12-week and 16-week timepoints, participants will provide outcome data including blinded CGM data, hemoglobin A1c, dietary intake, and other patient-reported outcomes and feedback on their experience using questionnaires. After study completion, a subset of sampled participants will be invited to complete a semi-structured interview regarding their experience with the study. Participants in the intervention group will be invited after the completion of the intervention (beginning week 13) and participants in the comparator group will be invited to interview after completion of the entire study (beginning week 17). The primary outcomes measuring study feasibility and acceptability will collect data related to CGM and FIM use, including overall retention and phase completion, CGM wear-time, use of food subsidy, completion of meal logs, and satisfaction for the intervention. The primary outcomes measuring efficacy will collect diabetes outcomes, glycemic management, and a suite of patient-reported outcomes. Quantitative and qualitative results will be used to improve the intervention prior to rollout of a subsequent multicenter, fully powered randomized trial.

Interventions

• Behavioral CGM-Augmented FIM
  The intervention arm will receive electronic healthy foods vouchers and unblinded, real-time CGM sensors for 16-weeks, in addition to individualized nutrition counseling with a registered dietician for 5-8 sessions (all participants will attend 5 sessions, with up to three additional sessions scheduled as needed based a set of a-priori decision rules).
• Behavioral FIM only
  The comparator arm will receive electronic healthy foods vouchers and healthy eating resources and self-directed nutrition education. This group will not receive unblinded CGM sensors or any nutrition counseling for the first 12 weeks. This group will receive 30-days of unblinded CGM sensors to use in the extension phase only.

Primary outcome measures

• Change in percent of Time in Range (TIR) [Time frame: Baseline at Week 0, Post-intervention at Week 12]
• Change in percent of Time Below Range (TBR) [Time frame: Baseline at Week 0, Post-intervention at Week 12]
• Change in percent of Time Above Range (TAR) [Time frame: Baseline at Week 0, Post-intervention at Week 12]
• Glycemic variability [Time frame: Baseline at Week 0, Post-intervention at Week 12]
• Change in Hemoglobin A1c (HbA1c) [Time frame: Baseline at Week 0, Post-intervention at Week 12]
• Change in Healthy Eating Index (HEI) Score based on two 24-hour recalls [Time frame: Baseline at Week 0, Post-intervention at Week 12, Post-extension at Week 16]
• Change in Mediterranean diet scores [Time frame: Baseline at Week 0, Post-Intervention at Week 12, Post-extension at Week 16]
• Change in Dietary Approaches to Stop Hypertension (DASH) Scores [Time frame: Baseline at Week 0, Post-Intervention at Week 12, Post-extension at Week 16]

Secondary outcome measures (12)

• Change in food security using the USDA Food Security Survey Module [Time frame: Baseline at Week 0, Post-intervention at Week 12, Post-extension at Week 16]
• Change in the presence and/or degree of nutrition security from the Two-item Nutrition Security Screener (NSS) [Time frame: Baseline at Week 0, Post-Intervention at Week 12, Post-extension at Week 16]
• Change in the summed nutrition barrier score from the Two-item Nutrition Security Screener (NSS) [Time frame: Baseline at Week 0, Post-Intervention at Week 12, Post-extension at Week 16]
• Change in the One-Item Gretchen Swanson Nutrition Screener [Time frame: Baseline at Week 0, Post-Intervention at Week 12, Post-extension at Week 16]
• Change in Core Diabetes Distress using the Type 2 Diabetes Distress Assessment System (T2-DDAS) Core Score [Time frame: Baseline at Week 0, Post-intervention at Week 12, Post-extension at Week 16]
• Change in Sources of Diabetes Distress using the Type 2 Diabetes Distress Assessment System (T2-DDAS) Source Scores [Time frame: Baseline at Week 0, Post-intervention at Week 12, Post-extension at Week 16]
• Changes in the Benefits of Continuous Glucose Monitor (BenCGM) [Time frame: Baseline at Week 0, Post-intervention at Week 12, Post-extension at Week 16]
• Changes in the Burdens of Continuous Glucose Monitor (BurCGM) [Time frame: Baseline at Week 0, Post-intervention at Week 12, Post-extension at Week 16]
• Changes in the 10-item Dietary Screener Questionnaire (DSQ) with a lookback of 30 days. [Time frame: Baseline at Week 0, Post-Intervention at Week 12, Post-extension at Week 16]
• Change in Physical Activity Levels [Time frame: Baseline at Week 0, Post-intervention at Week 12, Post-extension at Week 16]
• Change in Food Assistance enrollment (SNAP / WIC) in the last 30 days. [Time frame: Baseline at Week 0, Post-intervention at Week 12]
• Changes in financial strain, from the American Academy of Family Physicians (AAFP) Social Needs Screening Tool [Time frame: Baseline at Week 0, Post-intervention at Week 12]

Eligibility criteria

Inclusion criteria

• Able to complete study activities in English
• Aged ≥18 years
• Type 2 diabetes as defined by self-report and confirmed by ICD-10 codes

• Chart review will be conducted by the study team and a diagnosis of type 2 diabetes (E.11.xx) from either the problem list or a diagnosis linked to an encounter will be used as confirmation. Discrepancies in diagnosis codes will be resolved by review of provider notes within the past 3 years.
• HbA1c > 8.0% in the last 12 months via point of care or venous measurement. If there are multiple values, the most recent one will be considered.
• Receiving primary or specialty care within UNC Health as defined by at least one visit with a primary care provider or endocrine provider within the past year
• Indication of a barrier to healthy eating consisting of report of food insecurity (defined as a score greater or equal to 1.0 on the 6-item USDA Food Security Survey Module (FSSM)) and/OR nutrition insecurity (defined as more often than 'Rarely' on the One-Item Gretchen Swanson Nutrition Screener, OR more often than 'Not Very Hard' on the Two-item Nutrition Security Screener (NSS))

• Any positive screen on the FSSM, Gretchen Swanson Nutrition Screener, or NSS
• No plans to move from the area for at least 4 months
• Willing and able to provide written informed consent and participate in all study activities

Exclusion criteria

• Type 1 or other diabetes
• Use of insulin or secretagogues in the preceding 6 months
• Use of CGM in the preceding 6 months
• Inability to use CGM and related technology (e.g., the companion app), including lack of a smartphone that is compatible with Stelo (information on compatible phones available in Appendix 1) or known allergy to adhesive
• Known psychosis or major psychiatric illness that prevents participation with study activities
• Pregnancy or planned pregnancy in the next 4 months-glycemic targets are different for pregnant women compared to non-pregnant women with diabetes and our intervention is designed for non-pregnant glycemic targets
• Participant in diabetes, nutrition, or weight research intervention in last 12 months

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

United States · 1 center

• University of North Carolina at Chapel Hill — Chapel Hill

Identifiers

NCT: NCT07148713 · 24-2950 · 100001649496

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗