Emergency department visits provide an opportunity to identify people with undiagnosed, untreated, or uncontrolled high blood pressure. In Reach Out, we will test whether a mobile health intervention yields a greater reduction in blood pressure than usual care among individuals identified with high blood pressure during a safety-net emergency department visit. Subsequently, we will estimate the reduction in heart attack, stroke, and dementia if Reach Out were implemented across all U.S. safety-net emergency departments.

Hypertension is the most important modifiable risk factor for cardiovascular disease. Black Americans have the highest prevalence of hypertension and the lowest rates of blood pressure (BP) control of any racial or ethnic group in the U.S., contributing to cardiovascular disease disparities. Low-income Americans are also disproportionally burdened by hypertension. To achieve health equity, new approaches to hypertension management leveraging safety-net healthcare systems to reach underserved populations are needed.

One approach to addressing the hypertension epidemic is to identify and treat people undiagnosed, untreated, or with undertreated hypertension - people who have fallen through the cracks in the healthcare system. We did this in Reach Out 1 (R01MD011516), a mobile health (mHealth) 8-arm factorial trial of hypertensive patients recruited from a safety-net ED. Overall, systolic BP declined by 9.2 mmHg (95% CI -12.2 to - 6.3) after 6 months, without differences across treatment arms. Reach Out 1 successfully enrolled a hypertensive, medically underserved population into a mHealth intervention. Despite a very large reduction in BP overall, the efficacy of the Reach Out mHealth intervention is uncertain, given the lack of a control group.

Reach Out 2 proposes to test the most promising components of Reach Out 1 in a randomized open, blinded-endpoint (PROBE) controlled trial. Reach Out 2, continues our work with the same safety-net ED and Federally Qualified Health Centers. In Reach Out 2, we will compare usual care, to 6-months of prompted self-monitored blood pressure (SMBP) monitoring with tailored feedback and facilitated primary care appointment and transportation. The usual care group will receive instructions to follow up with a primary care provider after ED discharge. After 6 months, the intervention participants will enter an extended treatment period of long-term SMBP monitoring. To contextualize our findings, we will use our chronic disease agent-based simulation model to estimate the reduction in myocardial infarction, stroke, and dementia if Reach Out 2 were to be implemented in safety-net EDs across the US. The overarching goal of our proposal is to determine whether a low-tech mHealth intervention will reduce BP more than usual care among patients recruited from a safety-net ED and to understand the potential national impact of such an intervention. Because safety-net EDs are anchor institutions that care for large populations of medically underserved hypertensive people, mHealth strategies initiated here have tremendous potential to reduce cardiovascular inequities. To reach this potential, evidence based interventions to reduce BP must be identified (aim 1), long-term engagement evaluated (aim 2), and their impact understood (aim 3).

While in the ED, the patient must meet all of the following:

• Adult (≥18 y/o)
• At least one BP with Systolic BP ≥160 or a Diastolic BP ≥100 (criteria 1)
• If the patient has repeated measurements after achieving Criteria 1, at least one of the repeat BP remains systolic BP ≥140 or a diastolic BP ≥90
• Must have cell phones with text-messaging capability
• Likely to be discharged from the ED

Exclusion Criteria for Main Trial Participants:

• Critical illness
• Unable to read English (<1% at study site)
• Incarcerated
• Pregnant
• Pre-existing condition making 6-month follow-up unlikely

Data in which direct and indirect identifiers have been removed will be made available through data-sharing website

Before completion of trial data collection.