Gestational diabetes mellitus (GDM) is rapidly rising in prevalence and has been linked with several short and long-term adverse maternal health outcomes, including type 2 diabetes (T2DM) and cardiovascular disease. The postpartum year is a time of heightened risk, and 32-46% of people with GDM develop type 2 diabetes (T2DM) or Pre-Diabetes (PreDM) during the postpartum year. To prevent maternal diabetes, US guidelines recommend behavioral counseling to promote healthy eating, activity, and weight, but dissemination channels have been lacking. Evidence-based home visiting programs, with their well-established infrastructure in every state and focus on maternal and child health, are a promising platform through which the recommended behavioral interventions could reach people with GDM and reduce health disparities. Effective GDM intervention within home visiting needs to be potent, build on existing content, and remain brief, so as not to displace other evidence-based content. Integrating referral to medically tailored meals (MtMs) is a Food is Medicine strategy that may prevent and mitigate maternal diabetes in home visiting. Access to MtMs has been expanding rapidly in the US, with 10 states currently having and 5 states pending Medicaid Service waivers that offer coverage for MtMs. Systematic reviews have found that providing MtMs allows patients to experience significantly better glucose and weight management, improved food insecurity and dietary quality, and greater treatment satisfaction. MtMs also benefit health systems, insurers, and governments through reduced costs and fewer hospitalizations and emergency department visits. However, national calls and systematic reviews have identified a major evidence gap and the need for adequately powered effectiveness trials to determine whether MtMs are effective in treating and preventing maternal diabetes. For MtMs to continue as a treatment approach for GDM, compelling evidence is needed that they work and for whom and in what context. The primary aim of this study is to evaluate the 12-month incidence T2DM/PreDM in people with GDM who receive GDM Enhanced + Meals vs. GDM Enhanced Only within home visiting. A robust implementation process evaluation will inform ensure successful sustainment and reach for diverse pregnant and postpartum people with GDM. A Hybrid Type 1 effectiveness-implementation trial is proposed. The study will recruit 978 perinatal, English or Spanish-speaking adults nationwide from three clinical centers serving the West, Midwest/South, and East regions. Home visiting clients (35% Black; 40% Hispanic) with recent GDM diagnosis and will be randomized within site and home visiting agency to one of two treatment arms: GDM enhanced lifestyle intervention plus MtMs (GDM Enhanced + Meals) or GDM Enhanced Only. The primary study aim is to evaluate the 12-month incidence of T2DM/PreDM. Secondary aims will examine treatment group differences in health factors (weight, blood pressure) and client-centered outcomes (diet quality, physical activity, home food environment, food security, quality of life, treatment satisfaction, self-efficacy, mood) at 3, 6, and 12 months postpartum. Key moderators (Black/White race, Hispanic/Non-Hispanic ethnicity, food security), and mediators (changes in weight, dietary quality, physical activity, and the home food environment) will be identified. The RE-AIM framework will guide an implementation process evaluation to plan for successful delivery and sustainment of the interventions. Findings from this from large scale, adequately powered trial of MtMs for maternal health will fill a major gap in the literature. If the MTM approach is found effective, there will be strong justification to bolster access (at state level) and referrals (within home visiting) to MtMs. Findings will inform tailored strategies to ensure successful sustainment in home visiting and reach for diverse pregnant and postpartum people with GDM.
