Observational stepped-wedge analysis of a community health worker-led intervention for diabetes and hypertension in rural Mexico

OBJECTIVES: There is emerging interest and data supporting the effectiveness of community health workers (CHWs) in non-communicable diseases (NCDs) in low/middle-income countries (LMICs). This study aimed to determine whether a CHW-led intervention targeting diabetes and hypertension could improve markers of clinical disease control in rural Mexico. DESIGN AND SETTING: A prospective observational stepped-wedge study was conducted across seven communities in rural Chiapas, Mexico from March 2014 to April 2018. PARTICIPANTS: 149 adults with hypertension and/or diabetes. INTERVENTION: This study was conducted in the context of the programmatic roll-out of an accompaniment-based CHW-led intervention designed to complement comprehensive primary care for adults with diabetes and/or hypertension. Implementation occurred sequentially at 3-month intervals with point-of-care data collected at baseline and every 3 months thereafter for 12 months following roll-out in all communities. OUTCOME MEASURES: Primary outcomes were glycated haemoglobin (HbA1c) and systolic blood pressure (SBP), overall and stratified by baseline disease control. We conducted an individual-level analysis using mixed effects regression, adjusting for time, cohort and clustering at the individual and community levels. RESULTS: Among patients with diabetes, the CHW-led intervention was associated with a decrease in HbA1c of 0.35%; however, CIs were wide (95% CI −0.90% to 0.20%). In patients with hypertension, there was a 4.7 mm Hg decrease in SBP (95% CI −8.9 to −0.6). In diabetic patients with HbA1c ≥9%, HbA1c decreased by 0.96% (95% CI −1.69% to −0.23%), and in patients with uncontrolled hypertension, SBP decreased by 10.2 mm Hg (95% CI −17.7 to −2.8). CONCLUSIONS: We found that a CHW-led intervention resulted in clinically meaningful improvement in disease markers for patients with diabetes and hypertension, most apparent among patients with hypertension and patients with uncontrolled disease at baseline. These findings suggest that CHWs can play a valuable role in supporting NCD management in LMICs. TRIAL REGISTRATION NUMBER: NCT02549495.