Rationale and design of a comparative effectiveness trial to prevent type 2 diabetes in mothers and children: the ENCOURAGE healthy families study.

The number of youth with type 2 diabetes (T2D) is expected to quadruple over 4 decades. Gestational diabetes mellitus (GDM) is also increasing and is linked with development of T2D in women, and greater risk for T2D in adolescents exposed to GDM. Despite the increasing prevalence of T2D, approaches to prevent diabetes in high-risk youth and families are rare. To address this, we are conducting the Encourage Health Families Study (ENCOURAGE). This is a randomized trial evaluating the comparative effectiveness and costs of an adaptation of the Diabetes Prevention Program (DPP) directed at mothers who had GDM or prediabetes and their children. The intervention is a group-based lifestyle program which we developed and implemented in partnership with the YMCA. We are comparing the ENCOURAGE intervention targeted to 1) mothers who have had GDM or prediabetes, and 2) mothers who have had GDM or prediabetes along with their school-aged children. This manuscript provides 1) the rationale for a targeted approach to preventing T2D and the interventions, 2) description of the translation of the DPP curriculum, and 3) the study design and methodology. The primary aims are to determine if participation leads to 1) weight loss in high-risk mothers, and 2) youth having healthier weights and lifestyle habits. We will also evaluate costs associated with each approach. These data are essential to build a translation model of T2D prevention that is both realistic and feasible to address this growing problem in both youth and adults.