Intervention to Promote Weight Loss in Latinas At-risk for Diabetes

The overarching goal of this project is to develop and test a behavioral intervention delivered by promotoras to help at-risk Latinas lose weight and prevent diabetes.

The goal of the proposed research is to compare two evidence-based strategies for preventing type 2 diabetes - promotora-led lifestyle intervention and metformin - vs. usual care (UC) among Latinas in a "real world" setting. The aims of this study are to 1) develop a protocol-based, promotora-led lifestyle intervention (PLI) to promote weight loss in at-risk Latinas, and assess its feasibility; 2) compare changes in weight and cardiometabolic markers-hemoglobin A1C, fasting lipids, blood pressure-from baseline to 1 year between at-risk Latinas randomly assigned to the PLI group versus metformin and usual care (UC) groups; and 3) understand the social and cultural context surrounding weight-related behaviors among Latinas at-risk for diabetes. The investigators hypothesize that Latinas assigned to PLI and metformin will have greater weight loss (primary outcome) and greater improvements in cardiometabolic markers from baseline to 1 year than those randomized to UC

The Promotora-led Intervention consists of a core curriculum or 12 group sessions of 90 minute duration over a 12-week period and will be followed by a maintenance phase of 10 biweekly and then monthly 90-minute sessions during months 4 through 12. One promotora will lead each session in Spanish, exploring such topics as being active, low-fat diets, portion control, self monitoring, problem solving and life-style changes.

One physician visit at Puentes de Salud or Congreso Health Center to discuss healthy lifestyle behaviors that promote weight loss and diabetes prevention. During that visit, UC participants will also receive standard educational materials in Spanish from the NIDDK Weight-control Information Network covering the same topics. UC participants will receive another physician visit upon completion of 1-year follow-up to review laboratory assessments.

Participants randomized to the metformin arm of the study will receive this medication from months 1 through 12 after randomization. Subjects will receive 850 mg daily for 1 month and increase to 850 mg twice daily thereafter if no side effects are experienced.

Behavioral life-style program lead by a team of trained community health workers (called promotoras) with 2 principal goals - encouraging participants to lose 7% of their total weight and complete 150 minutes of moderate physical activity per week.

Participants in this arm will attend one physician visit to discuss healthy lifestyle behaviors and will receive standard educational materials.

Study tests difference in body weight (Weight in kg) between treatment conditions and usual care at 12 months.

Inclusion Criteria: Female gender Latino ethnicity Spanish fluency Age ≥20 years BMI ≥25 kg/m2 And "increased risk of diabetes" (ADA Diabetes Risk Score ≥4 as determine by 7-item questionnaire and hemoglobin A1C ≥ 5.6%) Exclusion Criteria: Hemoglobin A1C ≥ 6.5% Current or planned pregnancy during the study period Chronic conditions that could affect potential participants' ability to participate (osteoarthritis, heart disease, pulmonary disease requiring oxygen or daily bronchodilator use, and severe psychiatric disease) Medical comorbidities that could influence weight loss or weight gain (thyroid disease, cancer, and HIV) Medications that could affect weight or glucose metabolism (thiazide diuretics, β-blockers, and systemic glucocorticoids).