The purpose of this study is to find out whether a program called HEARTS can improve care for people who have both high blood pressure and diabetes. HEARTS was created by the World Health Organization to help primary care clinics deliver better treatment. It includes training for health workers, simpler treatment guides, better access to medicines, teamwork among clinic staff, and tracking systems to monitor patient care. In this study, 36 public primary care clinics in Guatemala will be randomly assigned to either use the HEARTS program or continue with their current care. About 1,440 adults who have both high blood pressure and diabetes will take part. Participants will be assessed at the start of the study and again after 12 months. The main measures are blood pressure and hemoglobin A1c (a blood test that shows average blood sugar levels over the past 2 to 3 months).

Hypertension and diabetes frequently co-occur and together are a leading cause of death and disability. Despite the availability of effective treatments, many patients remain untreated or uncontrolled. HEARTS is a package of implementation strategies recommended by the World Health Organization and Pan American Health Organization to improve cardiovascular disease management in primary care. To date, most HEARTS projects have focused on hypertension alone, and rigorous evaluations of HEARTS for integrated hypertension and diabetes care are lacking.

This cluster-randomized trial will be conducted in 36 Ministry of Health primary care facilities (Health Centers) in Guatemala. Health Centers will be randomized 1:1 to HEARTS or enhanced usual care. The HEARTS intervention consists of five implementation strategies adapted to Guatemala: (1) training and supportive supervision for health workers; (2) simplifying treatment protocols; (3) strengthening supply chains of medications and supplies; (4) task sharing with non-physician health workers; and (5) implementing quality monitoring systems. The comparator arm receives enhanced usual care, which includes standard Ministry of Health clinical care plus supply chain strengthening to ensure between-arm differences are not attributable to medication availability.

Approximately 1,440 patients with hypertension-diabetes multimorbidity (40 per facility) will be enrolled and assessed at baseline and 12 months. Co-primary outcomes are change in systolic blood pressure and hemoglobin A1c. Secondary outcomes include diastolic blood pressure, and proportions achieving blood pressure control (<130/<80 mmHg), hemoglobin A1c control (<7.0%), and combined control. A cost-effectiveness and budget impact analysis will be conducted from the health care sector perspective. The implementation period is 30 months, followed by a 12-month maintenance period.

Inclusion Criteria:

• Age ≥18 years
• Systolic blood pressure ≥130 mmHg on ≥2 occasions, defined as the mean of 6 measurements at 2 study visits scheduled at least 1 day apart but within 7 days
• Hemoglobin A1c ≥6.5%
• Able and willing to provide informed consent

Exclusion Criteria:

• Does not live in Health Center's catchment area or is unwilling to receive care at the Health Center
• Currently pregnant or planning pregnancy in the next 2 years
• Has been diagnosed with type 1 diabetes, or there is high suspicion of this diagnosis by study physicians
• Has severe chronic or terminal illness such that primary care management of hypertension and/or diabetes would be clinically inappropriate, including end-stage kidney disease
• Confined to bed
• Planning to leave the study area in the next 2 years
• Unwilling to comply with protocol requirements

De-identified individual participant data from the clinical trial will be shared via the NHLBI BioLINCC repository. Data will include sociodemographics, anthropometrics, medical history, blood pressure, hemoglobin A1c, and self-reported outcomes.

Data will be made accessible no later than the time of publication of the primary results or the end of the grant period, whichever comes first. Data will be available for a minimum of 10 years.

Controlled access through the NHLBI BioLINCC platform. Researchers must submit a data access request and sign a Data Use Agreement. Access and reuse will comply with NIH, institutional, and Guatemalan policies on data sharing and ethical guidelines.