Mexican American Trial of Community Health Workers: A Randomized Controlled Trial of a Community Health Worker Intervention for Mexican Americans With Type 2 Diabetes Mellitus

Objectives. We assessed whether community health workers (CHWs) could improve glycemic control among Mexican Americans with diabetes.Methods. We recruited 144 Mexican Americans with type 2 diabetes between January 2006 and September 2008 into the single-blinded, randomized controlled Mexican American Trial of Community Health Workers (MATCH) and followed them for 2 years. Participants were assigned to either a CHW intervention, delivering self-management training through 36 home visits over 2 years, or a bilingual control newsletter delivering the same information on the same schedule.Results. Intervention participants showed significantly lower hemoglobin A1c levels than control participants at both year 1 Δ = −0.55; P = .021) and year 2 (Δ = −0.69; P = .005). We observed no effect on blood pressure control, glucose self-monitoring, or adherence to medications or diet. Intervention participants increased physical activity from a mean of 1.63 days per week at baseline to 2.64 days per week after 2 years.Conclusions. A self-management intervention delivered by CHWs resulted in sustained improvements in glycemic control over 2 years among Mexican Americans with diabetes. MATCH adds to the growing body of evidence supporting the use of CHWs to reduce diabetes-related health disparities.The growing prevalence of diabetes mellitus among adults in the United States is well documented, with adverse impact strongest among ethnic minorities and low-income populations. The age-adjusted prevalence of diabetes is 12.6% among non-Hispanic Blacks, 11.8% among Hispanics, and only 7.1% among non-Hispanic Whites.1 Mexican Americans, who make up almost two thirds of US Hispanics,2 have an even higher diabetes prevalence of 13.3%.3 Disparities also persist in both processes of care and clinical outcomes. Mexican Americans with diabetes are significantly less likely than non-Hispanic Whites with the disease to be aware of and treated for comorbid hypertension or dyslipidemia.4 Mexican Americans are less likely to receive recommended clinical services, such as regular ophthalmologic and foot exams,5 and are less likely than non-Hispanic Whites to have well-controlled hemoglobin A1c (HbA1c) and cholesterol levels. In this context, it is not surprising that they are more than twice as likely as non-Hispanic Whites to be hospitalized for uncontrolled diabetes or long-term complications of diabetes5 and that they experience higher diabetes mortality rates.6–8 Although non-Hispanic Whites have experienced reductions in diabetes-related mortality in the past decades, Hispanics have not.8 Thus, unless effective public health strategies are identified and implemented, gaps in health outcomes are likely to grow.Community health workers (CHWs) are frontline public health workers who serve as liaisons between providers and community members, facilitate access to services, and improve both quality and cultural competence of service delivery.9,10 Several characteristics suggest that they may be well suited to addressing diabetes disparities. Because CHWs share culture, language, and knowledge of the community, they engage minority populations more effectively than the formal health care system can.11,12 Living and working in the same community as the people they serve, CHWs are able to provide individualized attention, focus on behavior-related tasks, and deliver regular feedback on the completion of those tasks.13 These qualities should lead to improved diabetes self-management and clinical outcomes. Although much has been written about CHWs in the past decade, few rigorous randomized controlled trials have tested this hypothesis,14–18 and the efficacy of CHWs in improving clinical outcomes in diabetes is not established. Of 6 published randomized controlled trials,19–25 only 2 demonstrated improvements in HbA1c levels among intervention participants, and both of these studies followed participants for only 6 months.19,24 Methodological limitations led the authors of a 2009 Agency for Health Care Research and Quality review to rate the published evidence as fair at best.15The Mexican American Trial of Community Health Workers (MATCH) sought to address these limitations of the literature through a rigorously designed behavioral randomized controlled trial with outcomes measured at 1 and 2 years. The primary study hypothesis was that the CHW intervention, compared with an attention control, would result in improvement in short-term physiological outcomes (mean HbA1c levels and percentage with controlled blood pressure). A secondary hypothesis was that the CHW intervention would improve adherence to self-management behaviors, such as daily self-monitoring of blood glucose, medication taking, and adherence to diet and physical activity recommendations.