EXECUTIVE SUMMARY

Given the high prevalence of undiagnosed hypertension, investigators are looking at how emergency providers can play a role in identifying and intervening with patients who present to the ED with high blood pressure (BP) readings. The idea is to catch the condition at an earlier stage so that patients do not end up returning to the ED with strokes, heart attacks, and other serious cardiovascular consequences from uncontrolled hypertension.

  • Investigators at Rhode Island Hospital in Providence have found that providing home-monitoring cuffs to patients with high BP readings in the ED can be a helpful tool in clarifying a hypertension diagnosis.
  • Taking the issue one step further, investigators at University of Illinois Hospital in Chicago are testing the effects of an ED-based intervention that has shown promise in using images and education to empower patients to take hypertension seriously, even though the condition generally is asymptomatic in its earlier stages.
  • One goal of such studies is to build an evidence base toward a uniform way to manage patients who present to the ED with uncontrolled hypertension.

Emergency providers see patients with elevated blood pressure (BP) readings every day. However, many emergency providers do not see it as their role to screen for the condition, let alone to commence treatment for a diagnosis that requires regular follow-up. Still, given the high prevalence of undiagnosed hypertension and the serious downstream consequences of not treating the condition, the thinking about ED intervention on this issue has begun to change in some quarters.

For example, investigators have begun to probe just how reliable BP readings taken in the ED are and whether subsequent home monitoring could clarify an accurate diagnosis. Taking it one step further, other researchers are testing the effects of an ED-based intervention aimed at empowering patients with high BP to take the condition seriously and access treatment before adverse cardiovascular problems occur.

The idea behind such efforts is to leverage the opportunity frontline providers have to identify and short-circuit the course of this disease. Doing so could reduce the number of patients who otherwise would present to the ED with strokes, heart attacks, and other avoidable complications that affect quality of life while significantly running up the tab on care costs.

Gather Evidence

Noting that the American College of Emergency Physicians released a clinical policy on asymptomatic elevated BP in 2013,1 Elizabeth Goldberg, MD, an assistant professor of emergency medicine at the Warren Alpert Medical School at Brown University and an attending emergency physician at Rhode Island Hospital in Providence, observes that it is clear her specialty recognizes that emergency providers see a lot of patients with elevated BP. Still, there is not a uniform approach to caring for these patients.

“It turns out we know very little about how to manage, how to treat, and how to screen patients with elevated BP in the ED,” Goldberg laments. “It is very important because hypertension is the leading modifiable risk factor for stroke and heart disease. ... We are very comfortable treating people with strokes and heart attacks when they come into the ED, but the thing that actually leads to stroke or heart attack — hypertension — we are not very comfortable treating.”

Given that the reason for this discomfort is likely the lack of research into how to screen and manage emergency patients with elevated BP, Goldberg and colleagues decided to conduct their own research. Their first endeavor to bear fruit is a new study of whether home BP monitoring can assist clinicians in detecting undiagnosed hypertension in ED patients with elevated BP readings.2

Investigators recruited patients in the ED at Rhode Island Hospital, a large, Level I trauma center.

“We approached patients who did not have a known diagnosis of hypertension ... but they had elevated BP readings when they came to the ED,” Goldberg says. “We asked them if they would be willing to take their BP at home using a device that we gave them for free ... if they agreed to do that, we provided them with a validated device.” Patients were excluded from the study if they were pregnant or admitted to the hospital, where they might be given medications for hypertension.

“We didn’t recruit patients who were already on high BP medications. That was an indication that they might not know they have high BP, but their doctor was already treating them for it,” Goldberg observes.

All patients included in the study registered BP readings equal to or greater than 120/80 mmHg during their ED visits and had no known history of hypertension. Goldberg explains that the BP readings were recorded in the ED using a research-grade device called the BpTRU that takes five BP measurements without a clinician in the room. This is to decrease the occurrence of “white coat” hypertension.

“Sometimes, when patients are right in front of the doctors, they are very nervous, and their BP goes up,” Goldberg notes. “The cool thing about the BpTRU is that ... patients push the start button, and the BP [measurements] cycle without anyone else in the room. It discards the first BP measurement and averages the other [four], and you get a more accurate BP reading.”

Upon discharge from the ED, the patients included in the study were asked to take and record their BP measurements every morning and evening for two weeks with the home-monitoring device. After the two weeks, patients were to return the device and their log of BP readings to investigators using a prepaid package that was provided to them at the time of their ED visit.

Out of 132 participants, 70% returned their home BP devices to investigators. The researchers averaged the BP readings, which produced intriguing results. If an average of all of a patient’s BP readings was higher than 135/85 mmHg, investigators concluded that the patient was hypertensive, Goldberg explains. Out of 39 patients who demonstrated prehypertension (a systolic BP of 120-139 or diastolic BP of 80-89) in the ED, investigators found that 31% actually were hypertensive based on their home BP measurements.

Among 38 patients with stage 1 hypertension (a systolic BP between 140 and 159 or diastolic BP between 90 and 99) in the ED, 50% were hypertensive based on their home BP readings. Among 25 patients with stage 2 hypertension (a systolic BP of 160 or higher or a diastolic BP of 100 or higher) in the ED, 75% were hypertensive based on their home BP readings.

From the study, investigators concluded that home BP monitoring following discharge from the ED can be a helpful tool in confirming a hypertension diagnosis. The findings regarding the third group of patients are particularly noteworthy, Goldberg suggests.

“If you come into the ED, and your systolic BP is greater than 150, your chance of having high BP is 75%. That is a really important group to make an impact on. The risk for stroke is pretty significant with untreated high BP, and these people might not see a physician for years,” she says. “People who come in with very elevated BP, even if they are in pain or they have anxiety ... that BP is a real reading. It is a real opportunity to make a difference in their subsequent healthcare course.”

However, precisely how to proceed most effectively with such patients is not so clear. In this study, many patients with undiagnosed high BP were on Medicaid, came from a lower socioeconomic class, or were not as health-literate as others.

“That patient population can be harder to get follow-up on,” Goldberg says. “It turns out that referring them to [other providers for follow-up] is not always the best answer because many of them don’t actually go to that follow-up appointment.”

Under ideal circumstances, there is an integrated health system in which primary care providers (PCP) can see what tests and medications have been started in the ED.

“The emergency provider can just be the first step and maybe start the patient on a first-line BP medication,” Goldberg offers.

She adds that a PCP could follow up, ensuring the patient is not experiencing side effects from the medication and adjusting treatment from there. However, Goldberg acknowledges that this type of arrangement still does not exist for most patients at this point.

Further, Goldberg acknowledges that many emergency providers do not see treating high BP as part of their role. “They don’t want to supplant PCPs. They see their role as taking care of acute emergencies,” she says. However, while establishing effective links to care should be a prime area for improvement, Goldberg counters that hypertension is a highly prevalent problem that emergency providers can address. “A lot of patients see us, and they don’t see PCPs. If we don’t take care of them, then who else will?”

Hypertension also is the subject of a randomized, clinical trial underway in the ED at the University of Illinois Hospital in Chicago. Over a five-year period, ED-based investigators will recruit 800 participants with uncontrolled high BP for which they are not receiving any treatment.

Half these patients will receive usual care, which consists of printed education about high BP and an outpatient referral for follow-up with a PCP. The other half will receive an intervention, which consists of a three-minute educational video on what causes hypertension and potential treatment options.

Intervention participants also will view ultrasound images that show the difference between a healthy heart and one affected by uncontrolled hypertension. These patients will interact briefly with a clinical pharmacist or an advanced practice nurse who will review current medications and provide more education.

Intervention patients will be provided with a cuff so they can monitor their BP readings at home. Patients without a PCP will be assigned one, along with a scheduled appointment.

Heather Prendergast, MD, MS, FACEP, the principal investigator on the study and a professor in the department of emergency medicine at the University of Illinois College of Medicine, explains the intervention is based in part on a pilot study she conducted on patients who were discharged from the ED with evidence of stage 2 hypertension.

“We did a limited bedside [echocardiogram] with these patients,” she observes. “We were looking for evidence of early subclinical changes. We were able to show patients in real time that this was their heart and these were changes that were starting to occur.”

The idea was to see if the images could be used to help educate and empower patients to take their BP seriously and make recommended changes.

“We did this pilot for a year and actually had great success,” observes Prendergast, noting that 83% of the patients showed improved BP readings and/or improved subclinical findings on echocardiogram exams conducted at the end of the one-year study.

The pilot results proved convincing to the National Institutes of Health, which then funded the current trial.

“We have a high-risk population in an urban setting. The area that I practice in has some of the highest rates of uncontrolled hypertension,” Prendergast reports. “We were able to demonstrate that this [intervention] could be impactful in terms of decreasing secondary cardiovascular complications.” The benefits of identifying and treating hypertension at an early stage are clear, Prendergast observes.

“The cardiovascular complications are not only costly to the system, but costly to the individuals because they severely impact their quality of life,” she says. “Many of our patients don’t even understand they have elevated BP because they haven’t started having complications from it. The first time they are aware of [high BP] is when they go into renal failure or heart failure.”

In the past, it has been difficult to get emergency patients with high BP to follow up with a PCP because they are not bothered by any symptoms. The intervention is designed to show patients why they need to take the condition seriously. “It seems from our pilot data that patients are receptive to it,” Prendergast notes.

From the start of the project, investigators understood the importance of making sure that the BP intervention was not disruptive to patient flow in the ED. Consequently, the research team is alerted to potential participants when their vital signs, including BP readings, are noted on the department’s track board.

“All patients get a repeat BP check [following an earlier BP check at triage] before they are discharged. If that second BP is greater than 140/90 ... then the patients are approached,” Prendergast explains.

Patients are excluded from the study if they are pregnant or if they are planning to leave the Chicago area within the next year. Also, researchers are excluding patients who cannot speak either English or Spanish. Otherwise, researchers engage with patients to see if they are interested in participating.

Patients randomized to receive the intervention can complete that process within 30 minutes, a short enough stretch so that their discharge is not delayed, Prendergast notes.

“When patients are identified for discharge, it will be an hour or more before they actually leave the department,” she says. “Our intervention is designed to capture them in that time between when they are identified for discharge and the time when they actually leave.”

Participants in both the usual care and intervention groups will be checked at three months and six months following the ED visit to see if their BP readings have changed.

Prendergast explains that she has always been focused on producing a streamlined approach that can be duplicated in many other settings. In fact, the next task on her list is to develop a toolkit to help other EDs start addressing hypertension.

“Right now, our usual care is just to notify patients [that they have high BP], and then refer them for follow-up. I believe that because we deal with the secondary cardiovascular complications, we have an opportunity to do some risk stratification and assessment of these patients,” she says. “We can actually ... stem the tide of a lot of this disability.”

REFERENCES

  1. Wolf SJ, Lo B, Shih RD, et al. Clinical policy: Critical issues in the evaluation and management of adult patients in the emergency department with asymptomatic elevated blood pressure. Ann Emerg Med 2013;62:59-68.
  2. Goldberg EM, Wilton T, Marks SJ, et al. Can home blood pressure monitoring assist in the detection of undiagnosed hypertension among emergency department patients with elevated blood pressure? Ann Emerg Med 2018;72:S45-S46.

SOURCES

  • Elizabeth Goldberg, MD, Assistant Professor, Emergency Medicine, Warren Alpert Medical School, Brown University; Attending Emergency Physician, Rhode Island Hospital, Providence, RI. Email: Elizabeth_Goldberg@brown.edu.
  • Heather Prendergast, MD, MS, FACEP, Professor, Department of Emergency Medicine, College of Medicine, University of Illinois, Chicago. Email: Hprender@uic.edu.