Nested Pilot Study Comparing Two Treatments to Reduce Type 2 Diabetes Risk in At-Risk Delawareans

Prediabetes affects over one-third of Delaware residents, placing more than 70% at risk of developing type 2 diabetes (T2D) within a decade if left untreated. This public health burden disproportionately impacts diverse population segments, including racial/ethnic minority groups and those with lower income and education; groups who are less likely to benefit from current prevention strategies. The 12-month National Diabetes Prevention Program (DPP) is the first-line intervention to prevent T2D, but only 35% of participants achieve the recommended ≥5% weight loss, with non-responders more likely to reside in high-priority communities. Moreover, comorbid conditions such as hypertension remain inadequately addressed. Sleep health improvements and time-restricted eating (TRE) are two promising, evidence-based strategies shown to enhance metabolic and cardiovascular outcomes. Despite recommendations from national guidelines for diabetes prevention and management to include sleep health, their widespread implementation is limited by the lack of an effective delivery platform. Expanding the DPP to include these interventions (creating the "DPP++"; DPP + sleep health + TRE) could provide a scalable solution to enhance efficacy and improve access to diabetes prevention across all communities. This 12-month Clinical and Translational Research (CTR) pilot study will evaluate the clinical efficacy of DPP++ compared to the standard DPP among adults at risk for T2D already enrolled in DPP cohorts administered by the University of Delaware Nutrition Clinic. Focused community-engagement efforts that are overseen by the study steering committee will target traditionally overlooked populations to enroll in these cohorts. Between months 1-3 of the standard DPP, participants will be invited to join a nested randomized controlled trial. In month 4, consenting participants will be randomized to either the standard DPP (control) or DPP++. Aim 1 of this study will compare the efficacy of DPP++ vs. standard DPP on metabolic health at 6 and 12 months. Aim 2 will assess DPP++ vs. standard DPP differences in cardiovascular health and quality of life. Completing this pilot will also support the capacity for integrating the sleep health and TRE intervention components into clinical practice.

Inclusion criteria

• Adults aged 18 years or older
• Prediabetes confirmed by blood test result within 12 months of enrollment, previous diagnosis of gestational diabetes mellitus (GDM), or positive screening for prediabetes based on the Prediabetes Risk Test
• BMI of 25 kg/m² or greater (23 kg/m² or greater for Asian Americans)

Exclusion criteria

• Age younger than 18 years
• BMI less than 25 kg/m² (less than 23 kg/m² for Asian Americans)
• No current diagnosis of prediabetes or gestational diabetes mellitus
• Prior diagnosis of type 1 or type 2 diabetes
• Pregnancy at the time of enrollment
• Development of a medical condition that, in the PI's judgment, could be exacerbated by the study interventions (e.g., eating disorder, severe sleep disorder)