Compared to non-Hispanic whites, Hispanics and African Americans with type 2 diabetes experience lower rates of control of risk factors (glucose, blood pressure, lipids), and higher rates of end-organ complications. To address these disparities, new models of primary care are needed. The use of Community Health Workers (CHWs) has been advocated as one approach, and preliminary research findings have been encouraging. The MATCH randomized controlled trial tested the impact of behavioral self-management coaching delivered in participants' homes by CHWs over a two-year period in a community setting. This rigorous Phase III efficacy trial demonstrated that the MATCH intervention was effective in producing a sustained improvement in Hemoglobin A1c in a Mexican-American population. Participants in the intervention arm had a mean reduction of A1c levels of 0.48 from baseline at the end of year 1 (p=0.021) and an even greater decrease of 0.72 two years post-randomization (p=0.005); the attention control group showed no change. Although mean arterial blood pressure improved relative to control at one year, this improvement was not sustained. The proposed MATCH2 Study (The Multi-clinic Action Trial to Control Hyperglycemia and Hypertension) will test an optimized intervention building on the MATCH protocol in which CHWs will be integrated into the primary care team at three urban safety clinics. A Community Based Participatory Research approach will be used to adapt the CHW intervention to the clinic setting, and to enhance the ability of CHWs to work effectively with health disparity populations of different races/ethnicities. Web-based communications will allow CHWs in participants' homes to rapidly update providers in the clinic. The intervention curriculum has also been strengthened, emphasizing self-monitoring, diet, and physical activity, with increased emphasis on blood pressure as well as glucose. The RCT will test if this optimized intervention, compared to a lower intensity group educational program, can reduce both Hemoglobin A1c levels (Specific Aim 1), and blood pressure (Aim 2) at eighteen months in persons with uncontrolled diabetes (A1c >7.0 at baseline). Follow-up six months after the completion of the intervention will evaluate the sustainability of any gains (Aim 3). Use of more precise measures of diet (food frequency questionnaires) and physical activity (accelerometry) will seek to identify intermediate behaviors and processes that mediate significant improvements in glycemic and blood pressure control in the MATCH CHW intervention (Aim 4). Finally, all costs borne by both the program and the participant will be documented, in order to evaluate costs and benefits (Aim 5). By building on and strengthening the MATCH intervention, the overarching goal of this study is to set the stage for a multi-center effectiveness trial to determine the external validity and replicability of the CHW model in reducing health disparities.
With improvements in glycemic control over a two-year period, the rigorous MATCH trial demonstrated that Community Health Workers (CHWs) could improve diabetes control among Mexican-Americans. The proposed MATCH2 intervention builds on this, seeking to test the intervention among African Americans and Latinos in primary care clinic settings, and determine if the intervention has a sustainable impact on both glucose levels and blood pressure. A Community Based Participatory Research approach will aid in participant enrollment, acceptance of the intervention by patients and their physicians, and sustainability. If this enhanced intervention is found to be efficacious in improving both A1c and blood pressure, MATCH2 will set the stage for a multi-center effectiveness trial of a relatively low cost CHW intervention that may reduce diabetes health disparities.
