The Silent Number: Should the Emergency Department Treat Asymptomatic Hypertension at All?
The Case
A woman in her fifties presents to the emergency department with a laceration across the back of her hand. She was slicing a mango. It needs a few stitches. This is a fifteen minute visit on a good day.
Then the nurse cycles the blood pressure cuff, and the number that comes back is 182 over 112.
She feels completely fine. No headache, no chest pain, no visual disturbance, no focal deficit, no dyspnea. Her history is unremarkable. She has no primary care physician and has not had a set of vitals taken in about four years. She just wants her hand fixed so she can get back to work.
And now there is a decision to make that is genuinely one of the more contested calls in emergency medicine. Do I do anything about that number? Do I treat it in the department? Do I send her out with a prescription? Or do I repair the laceration, say nothing, and let it become somebody else's problem?
Why This Question Matters
Start with the scale, because it is genuinely staggering. Roughly 120 million American adults have poorly controlled high blood pressure.7 * That means something close to a third of the country is carrying a deadly and, here is the operative word, modifiable risk factor for the leading cause of death we have. Hypertension is not a passive bystander in that story. Something on the order of 47 percent of coronary heart disease and 54 percent of strokes worldwide are attributable to elevated blood pressure.6 * If those numbers do not bother you, they should.
Now layer the emergency medicine problem on top. A very large share of these people are not seeing a primary care physician. They are, however, coming to us. For a laceration, an ankle sprain, a cough, a rash. And while they are sitting in front of us, the cuff reveals the silent number. The emergency department becomes, whether we chose the role or not, the place where a massive public health problem surfaces in plain sight.
The tension is real and it cuts both ways. The ED is a terrible place to diagnose chronic hypertension off a single reading. Pain drives pressure up. Anxiety drives pressure up. Alarms are sounding, the lights are on, and nobody is relaxed. It is not a day spa. But if we do nothing at all, we may be squandering the only contact this person has with the healthcare system all year.
So the paper we are looking at asks a sharp, practical question. When emergency physicians do prescribe an antihypertensive to a discharged patient, is that associated with better short term outcomes?
The Paper, in PICO
Todd and colleagues, writing in the Journal of the American College of Emergency Physicians Open in 2024.1 One honesty note before we go any further. This is not a randomized controlled trial. It is a large observational cohort study, which means we are talking about associations rather than proof of cause and effect. Keep that flag flying the whole way through.
Population
All discharged adult emergency department patients with a diagnosis of hypertension across an eight hospital health system, screened from January 2016 through February 2020. The system served a mix of suburban and urban patients with broad ethnic and socioeconomic representation. The final sample was 93,512 ED visits. The cohort was 57.5 percent female with a mean age of 59.3 years.1
Intervention
Receiving a prescription for oral antihypertensive medication at the point of ED discharge. Only 4.7 percent of the cohort did.1
Comparator
Being discharged with no antihypertensive prescription. That is the overwhelming majority of this population, which is itself the most important descriptive finding in the paper.
Outcome
The primary outcome was a severe composite adverse event attributable to hypertension within 30 days of discharge, defined as aortic catastrophe, heart failure, myocardial infarction, hemorrhagic or ischemic stroke, or hypertensive encephalopathy. Secondary outcomes were death and ED revisit over the same 30 day window. Analyses were adjusted for age, race, degree of hypertension, whether the patient was treated for elevated blood pressure in the department, Elixhauser comorbidity index, and history of heart failure.1
What the Data Showed
The first thing that jumps out of this paper is not the effect size. It is how little we are doing.
Across 93,512 discharged ED visits carrying a diagnosis of hypertension, 4.7 percent left with a prescription for an antihypertensive.1 Fewer than 1 in 20. For the overwhelming majority of these patients, an elevated number was quietly documented and then nothing happened.
Within 30 days of discharge, 0.7 percent of the whole cohort experienced a severe adverse event, 0.1 percent died, and 15.2 percent returned to the emergency department.1
And here is the headline. After adjustment, patients who received a prescription at discharge had substantially lower odds of a severe adverse event, with an adjusted odds ratio of 0.224 and a 95 percent confidence interval of 0.106 to 0.416. They also had lower odds of an ED revisit, with an adjusted odds ratio of 0.610 and a 95 percent confidence interval of 0.547 to 0.678. There was no difference in the odds of death at 30 days.1
Now I want to be disciplined here, because this is exactly the kind of result that is easy to oversell. An adjusted odds ratio of 0.224 on a composite outcome is a dramatic looking number. It is also an association drawn from observational data, and it is entirely plausible that the patients who got prescribed differed in ways the adjustment could not fully capture. That is a serious limitation, and I come back to it hard below. But the signal is worth taking seriously, especially against a backdrop where 95 percent of these patients walk out with nothing.
Critical Appraisal
What is good
• The scale is real. A denominator of 93,512 ED visits across eight hospitals captures messy, everyday practice rather than a hand picked trial population. That gives the descriptive findings, and particularly the prescribing rate, a great deal of external credibility.
• The outcome is patient centered. This is not a study of blood pressure numbers at 30 days. The composite is built from aortic catastrophe, heart failure, myocardial infarction, stroke, and hypertensive encephalopathy. Those are events patients care about, not surrogates.
• The adjustment is thoughtful. Adjusting for Elixhauser comorbidity index, heart failure history, degree of hypertension, and whether the patient was treated in the department addresses several of the most obvious confounders directly.
• It shines a light on a genuine care gap. The single most important thing this paper tells us is not the odds ratio. It is that we intervene in fewer than 1 in 20 of these patients. That finding alone should make us uncomfortable, in a productive way.
What is not so good
• It is observational, and that is the big one. This design cannot establish that the prescription caused the better outcome. There is substantial potential for confounding by indication, where clinicians chose to prescribe precisely for the patients they judged most likely to benefit, most likely to adhere, or most likely to follow up. Association is not causation, and the effect size here is large enough that residual confounding deserves serious weight.
• The confidence interval is wide. An interval running from 0.106 to 0.416 sits on a small number of events. With 0.7 percent of the cohort experiencing the primary outcome, the absolute event count driving that estimate is modest.
• A single ED reading is a poor diagnostic instrument. Pain, anxiety, and the sheer noise of the department push pressure up. An elevated number in the ED is a prompt to investigate, not a diagnosis carved in stone. A 2025 scoping review found that even the definition of asymptomatic hypertension varies widely across the literature, with no consensus on thresholds, on diagnostic testing, or on whether treatment should be initiated in the department at all.4
• Single health system, and pre pandemic. One eight hospital system in one region, with data ending in February 2020. Prescribing culture, follow up availability, and patient behavior all shifted considerably after that point.
• The guideline is cautious for good reasons. The American College of Emergency Physicians clinical policy does not routinely recommend initiating antihypertensive therapy for asymptomatic elevated blood pressure in the ED, and it warns that lowering pressure too rapidly can cause harm. It does carve out recommendations for selected at risk populations. There is a legitimate, evidence based reason to be conservative here, and it deserves to be represented fairly because it is the mainstream position.3
Holding both at once
So how do you reconcile a cautious guideline with a paper suggesting benefit? You hold both, and you notice that they are answering different questions.
The guideline is right that we should not be aggressively driving pressures down in the department off a single reading. Rapid reduction has documented harms, and reflexive testing in asymptomatic patients has repeatedly been shown to be low yield. A clinical pathway study in a Veterans Health Administration emergency department found that standardizing care reduced unnecessary chest radiographs from 10 percent to 0 percent with no major adverse cardiovascular events in either period, and that at no point did diagnostic testing identify a previously undiagnosed condition.5
The paper is right that doing absolutely nothing, for an entire visit, is also a failure. Those two statements are compatible. The space between them is where the actual clinical work lives.
How Should This Modify Your Practice?
Here is where I land, and I will be candid that I sit toward one end of the spectrum on this. We in the emergency department have an extraordinary privilege of access. In my experience it is close to impossible for an unattached patient to establish care with a primary physician within 30 days of an ED visit. Saying nothing at all about a genuinely elevated pressure feels like a disservice to a patient who may not be seen again for years.
My compromise is not to reflexively start a drug and rush the pressure down. It is to spend a few focused minutes on three things.
1. Teach home measurement, properly. Counsel the patient to buy an inexpensive validated upper arm cuff, sit quietly with the arm supported at heart level, and measure at two set times a day for seven days, logging every reading. Tell them explicitly not to react to any single value. The seven day home average is a far better estimate of true blood pressure than anything the department can generate, and it converts a vague worry into something an outpatient clinician can act on.
2. Name the modifiable levers out loud. Weight, dietary pattern, physical activity, sodium reduction, alcohol moderation, and tobacco cessation. Thirty seconds of concrete counseling from a physician in scrubs lands differently than a pamphlet. This is also the Tier 1 conversation: establishing a relationship with a primary care physician is itself a foundational health intervention, not an administrative afterthought.
3. Open the medication conversation when it fits, rather than issuing a script without one. For the genuinely high risk patient, or the patient in a category the ACEP policy specifically flags, that conversation may well end in a prescription with clear follow up instructions. Frame it around the patient's values and their realistic access to follow up, not around the number on the monitor.
There is one more thing worth saying to trainees in particular. Do not let the strange corners of the internet convince your patients that physicians never discuss lifestyle and are simply pill mills. That claim is nonsense, and the ACC and AHA hypertension guideline is the easiest possible rebuttal. Lifestyle modification sits at the structural center of that document, not in a footnote.
The Bottom Line
1. Asymptomatic hypertension is everywhere in the emergency department, and we intervene astonishingly rarely. Fewer than 1 in 20 discharged patients with a hypertension diagnosis left with a prescription. That care gap is the loudest finding in this paper.
2. Prescribing an antihypertensive at discharge was associated with markedly lower odds of a 30 day severe adverse event and of ED revisit, with no difference in mortality. This is observational data, so treat it as a strong signal to engage rather than as proof that a prescription is the right answer for everyone.
3. The move is not to drive the pressure down off one reading. It is to teach structured home monitoring, name the modifiable levers, and have a values based conversation about medication, escalating to a prescription for the right patient with the right follow up plan.
About the Author
Adrian Cois, MD is an Emergency Medicine physician and Assistant Professor with a background in exercise physiology and sports performance coaching. He is the host of Overheard in the Emergency Room and writes about evidence based medicine for everyday people at DrCois.com.
Disclosures. The author reports no financial relationships with any product, service, or company mentioned in this article. No commercial sponsorship was received for this episode or post. No affiliate links appear anywhere on this site.
Disclaimer. This article is for educational purposes only. It does not constitute medical advice and does not establish a physician and patient relationship. Always discuss management decisions with a qualified clinician who knows your history.
Related Reading on DrCois.com
• Overheard Journal Club Episode 1: ABNORMAL Saline, and Why I Stopped Reaching for the Yellow Bag
• Quick Hits Episode 6: How to Read a Medical Paper Without Losing Your Mind
• The Two Tier Blueprint: Why a Primary Care Physician Is a Tier 1 Foundation, Not an Optional Extra
• Main Episode: Hypertension, Shared Decision Making, and the Conversation Nobody Has Time For
References
1. Todd BR, Xing Y, Zhao L, Nguyen A, Swor R, Eberhardt L, Bahl A. Antihypertensive prescription is associated with improved 30-day outcomes for discharged hypertensive emergency department patients. J Am Coll Emerg Physicians Open. 2024;5(2):e13138. doi:10.1002/emp2.13138
2. Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults. Hypertension. 2018;71(6):e13-e115. doi:10.1161/HYP.0000000000000065
3. American College of Emergency Physicians. Clinical policy: critical issues in the evaluation and management of adult patients in the emergency department with asymptomatic elevated blood pressure. https://www.acep.org/patient-care/clinical-policies/asymptomatic-elevated-blood-pressure
4. Degtyar A, Wilder ME, Richardson LD, Souffront KT. A scoping review of asymptomatic hypertension: definitions, diagnosis, and management in the emergency department. Curr Hypertens Rep. 2025;27(1):18. doi:10.1007/s11906-025-01335-6
5. Farkas A, Turner T, Sherman K, Pavlic A. Implementation of a clinical pathway for the evaluation of asymptomatic hypertension in the emergency department. Am J Emerg Med. 2024;86:37-40. doi:10.1016/j.ajem.2024.09.042
6. Wu CY, Hu HY, Chou YJ, Huang N, Chou YC, Li CP. High blood pressure and all-cause and cardiovascular disease mortalities in community-dwelling older adults. Medicine (Baltimore). 2015;94(47):e2160. doi:10.1097/MD.0000000000002160 *
7. Examining the hypertension control cascade in adults with uncontrolled hypertension in the US. JAMA Netw Open. https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2823542 *
8. Monitoring blood pressure at home can be tricky. Here's how to do it right. American Heart Association. https://www.heart.org/en/news/2022/05/23/monitoring-blood-pressure-at-home-can-be-tricky-heres-how-to-do-it-right
