PROJECT SUMMARY/ABSTRACT Women with a history of gestational diabetes mellitus (GDM) are at high risk of developing type 2 diabetes (T2DM). Evidence from the Diabetes Prevention Program indicates that lifestyle change and metformin use in this population are clinically equivalent, each reducing the incidence of T2DM by approximately 50% among women with a GDM history. These women face a preference-sensitive decision between the evidence-based alternatives. Shared decision making (SDM) is an attractive approach in this situation, using a decision aid to make the decision explicit, describe the available options with equipoise, elicit patient preferences, and help patients make an informed decision that is right for them. To our knowledge, there are no existing studies evaluating SDM for diabetes prevention among women with a history of GDM. Our team has extensive experience with a team-based SDM approach for diabetes prevention, and our prior work showed that this approach leads to increased uptake of an evidence-based diabetes prevention strategy (lifestyle change, metformin or both) as well as sustained weight loss at 12-month follow-up in a broader population with prediabetes. We have also completed a pilot test of SDM among 33 women with a GDM history, demonstrating feasibility and acceptability. In this proposal, we aim to evaluate SDM for diabetes prevention among women with a history of GDM and prediabetes within two health systems (UCLA and Intermountain). Pharmacists will implement the intervention at UCLA, and clinic care managers will implement the intervention at Intermountain. Our Specific Aims are as follows: To test the effectiveness of an RCT evaluating SDM for diabetes prevention on 1) weight loss among overweight/obese women with a history of GDM and hemoglobin A1c between 5.7-6.4%, 2) uptake of lifestyle change and/or metformin use, patient- reported outcomes (physical activity, eating patterns, patient activation, health-related quality of life), annual follow-up screening for progression to T2DM, and rates of GDM in a subsequent pregnancy (exploratory outcome), and 3) to evaluate the incremental cost of program implementation per woman with a history of GDM and hemoglobin A1c between 5.7-6.4% who successfully initiates lifestyle change and/or metformin. Our application presents a unique opportunity to implement a rigorous project addressing a critical area of unmet need in diabetes prevention for women with history of GDM, leveraging our health system infrastructure and our collaborative, multidisciplinary team with a strong record of accomplishment in diabetes prevention. This work will provide pragmatic, effective and sustainable approaches to increase evidence-based diabetes prevention strategies for women with a history of GDM that can be readily adopted in other health systems.

PROJECT NARRATIVE Women with a history of gestational diabetes mellitus (GDM) are at high risk of developing Type 2 diabetes. We are proposing a randomized controlled trial evaluating shared decision making for diabetes prevention among overweight/obese women with a history of GDM and hemoglobin A1c between 5.7-6.4%. The primary study outcome is loss of >5% of body weight, and secondary study outcomes include uptake of behavior change, use of metformin, and increased follow-up screening for diabetes.