Blood Pressure-Improving Control Among Alaska Native People" (BP-ICAN)

Background:

Cardiovascular disease (CVD) and stroke have become leading causes of mortality among ANAI people, who experience CVD disparities in incidence, risk factors, and mortality, especially for stroke, compared to the general population. From 1994-2003 stroke mortality in ANAIs was at least 25% higher than for Whites in Alaska. Over the same period, stroke mortality for ANAIs under age 45 increased 400%, but declined in Whites. In addition, the decline in age-adjusted CVD mortality observed in recent decades within the general population does not extend to ANAIs. Controlling hypertension is a pillar of prevention for CVD and stroke.

Although ANAIs were formerly thought to have a very low prevalence of stroke and CVD, more reliable newer data indicate high levels of hypertension and associated mortality. A recent systematic review of 141 publications on hypertension in ANAI people documented a significant increase in recorded prevalence over the past 3 decades, as well as a significantly higher prevalence in ANAI adults than in reference populations, usually White. Aggregated data from the Behavioral Risk Factor Surveillance System (BRFSS) also show a higher prevalence of self-reported hypertension in ANAIs than in non-Hispanic Whites (27% vs. 22%). The National Health Interview Survey found a similar disparity of 35% vs 26% in ANAIs vs. Whites. As in non-Hispanic Whites, 61% of ANAIs with hypertension were taking anti-hypertensive medication. In a previous study, an investigator on the present proposal examined the health records of 524 ANAI elders, finding that 23% had undiagnosed hypertension, and 38% had diagnosed hypertension. Of those with diagnoses, 81% were taking medication, 37% had well-controlled blood pressure (BP), and lifestyle counseling was rare.

Ongoing management of high BP often requires healthcare providers to initiate or intensify therapy in response to uncontrolled high BP. A recent review concluded that the patient/provider relationship, patient/provider communication, and patient-centered decision making were essential to appropriate decisions on medication change. Another study using electronic health record (EHR) data on military veterans found that ~60% of patients with hypertension had poorly controlled systolic BP, yet less than half of clinicians made medication changes after a computer-generated notification.

Improving BP control requires the involvement not only of individuals but of healthcare systems and social environments. Communications must extend care to patients "where they are" outside the clinic; facilitate BP self-management; and minimize barriers to care AN/AIs face in healthcare access. Across Alaska, 60% of residents are medically underserved, and in 75% of Alaskan communities, regardless of residents' race, comprehensive healthcare services are accessible only by air or water. Even in urban areas, health disparities among AN/AIs persist, and access to care is affected by factors such as lack of transportation.

CVD morbidity, mortality, and organ damage are more accurately predicted by home blood pressure monitoring (HBPM) than by in-office measurements. HBPM avoids over-treating sporadic high BP readings and "white coat" hypertension while facilitating control of both resistant and "masked" hypertension (high at home and normal in the clinic), which are associated with stroke. Compared to usual care or HBPM alone, HBPM combined with self-titration of medications or with physician, pharmacist, or nurse management leads to better use of medications and BP control. Research shows the value of using HBPM values to trigger modifications in anti-hypertensive regimens, and the addition of provider feedback, patient and provider education, and decision-making support to encourage treatment adjustments improves control even more. HBPM can support patient decision making, provide data to providers, facilitate patient/provider communication, and engage, educate, and empower patients. HBPM devices are widely accepted by patients, who prefer them to clinic-based measurements. HBPM interventions appear to be most effective in patients with less well-controlled BP at baseline. Therefore, tailored HBPM interventions have been developed for minorities, who may receive more benefit from HBPM than Whites.

Significance:

BP-ICAN is innovative in many ways. First, it will be the only rigorous, population-based study about BP control for prevention of CVD and stroke in ANs, and one of very few multilevel interventions in any minority population. Second, the Southcentral Foundation (SCF) service area includes rural, suburban, and urban locations. Third, our intervention design addresses therapeutic inertia, a well-recognized barrier to hypertension control that is often neglected in clinical trials, so our approach to improve self-efficacy and ownership should lead to more timely communication with providers and titration of medications.

The investigators will conduct a group-randomized trial for improving BP control among ANAI adults with diagnosed hypertension (Figure 2). Study group assignment will occur by randomizing all SCF primary care panels to the BP-ICAN or usual care control arms; adults with uncontrolled hypertension will be nested within groups defined by panel, which corresponds to one provider. For each panel, investigators will recruit up to 10 ANAI adults (expecting average of 8-9 per provider, for a total n = 500) who have had systolic BP ≥ 130 mmHg measured at one or more clinic visits in the past 18 months OR who have previously diagnosed hypertension and systolic BP ≥ 130 mmHg measured at their study screening visit. The study period for all participants will last 12 months.

Participants who are randomized to the BP-ICAN arm will receive education about BP control, CVD and stroke and the importance of hypertension management for prevention, other lifestyle changes that can prevent or reduce morbidity from hypertension, and educational materials about the importance of timely response to uncontrolled hypertension. BP-ICAN arm participants will also receive HBPM equipment (Omron device) and training in its use, interpretation of results, and assistance with communicating high BP values to their healthcare providers. Lastly, participants will receive culturally tailored text messages to reinforce the educational material and motivate adherence to HBPM and provider communication strategies. Participants whose providers have been randomized to the control condition will continue to receive care as usual.

Patient-initiated communication about uncontrolled BP will serve as one component of the provider-level intervention. Participants will be trained to sync their HBPM and smartphone to automatically upload their BP measurements into a data repository using Omron's free iOS and/or Android wellness application. This will update the participant's data on Omron's Wellness Application website (https://omronhealthcare.com). Investigators plan to use Validic, a cloud-based technology platform to serve as a data repository and are working with tribal leadership, institutional privacy officers, compliance officers, and providers on how data will displayed and stored within the health care system. The goal is to make aggregate BP measure data available to providers in either a personal health record (PHR) and/or health information exchange (HIE) that allows for transmission of select measures into the electronic health and or population health record. Note that this protocol was developed based on extensive collaboration with SCF providers.

At the individual level, the primary outcome is within-person change in systolic BP. Secondary outcomes are diastolic BP, anti-hypertensive medication use and adherence, physical activity, weight, and tobacco use. Individual-level outcomes will be measured at baseline, 3 months, 6 months, and 1 year post-baseline. At the provider level, the primary outcome is change in prescribing behavior for medication and other relevant lifestyle changes. At the systems level, the primary outcome is change in systolic BP for all adults with hypertension whose providers are randomized to the BP-ICAN arm vs. the care as usual arm, regardless of whether the adults were directly enrolled into the study.