Undiagnosed hypertension is common among urban emergency room patients

Philadelphia, PA - An observational study of adults presenting to the emergency departments (EDs) in four US inner-city hospitals found that unrecognized or poorly controlled hypertension is common, especially among African Americans. The report is published in the September 2005 issue of Academic Emergency Medicine^[1] .

It is estimated that one in four adults in the US has hypertension, and early identification and management of this condition is known to reduce cardiovascular disease, stroke, and renal disease. To date, however, there has been little systematic study of patients who present to the emergency room with hypertension. Dr David J Karras (Temple University School of Medicine, Philadelphia, PA) and colleagues investigated such a population to assess presenting symptoms and determine the prevalence of elevated BP after discharge.

The study was conducted in 2002 at the emergency departments of four primary teaching hospitals of medical schools serving largely economically disadvantaged patients in Philadelphia, New York, Atlanta, and Miami. All patients age 18 and older who presented to these four EDs during a one-week period and had a diastolic BP of >90 mm Hg or a systolic BP of >140 mm Hg were eligible to participate. Of 7238 presenting patients, 1440 fulfilled the study criteria, and 1396 were enrolled. A total of 893 study subjects consented to be interviewed in a follow-up phone call three weeks after the ED visit, and of these, 334 randomized subjects were contacted.

African Americans and Hispanic subjects made up 63.1% and 21.6% of the study population, reflecting the ethnic composition of patients seen in the four EDs. Almost half (46.6%) were uninsured.

Elevated BP values were highly prevalent. African Americans were more likely to have stage 2 and 3 values than stage 1 values (p<0.001), whereas the reverse was true for non-Hispanic white patients.

BP stages of 1396 emergency room patients with hypertension

One third of patients presented with a chief complaint of a hypertension-associated symptom—chest pain, dyspnea, dizziness, neurologic deficit, mental-status change, headache, epistaxis, and hematuria—which may reflect end-stage organ dysfunction.

The team found that BP stage declined in fewer than half of ED patients with elevated BP values who had serial measurements. "This suggests that an elevated BP value in an ED patient should not be discounted as a transient phenomenon," Karras writes.

Among patients who were followed at three weeks and saw a primary-care physician after discharge from the ED, one fourth reported that their BP remained elevated. "This lends further support to the argument that even mildly elevated BP values in ED patients should not be discounted."

Study limitations include the fact that this was an exploratory study, findings might not translate to other practice settings, and measurement of BP was not standardized.

Half of the patients showing up in the emergency room with elevated BP reported that they were not under medical care for hypertension. "Our findings support the assertion that the ED may be an appropriate location for identifying previously undiagnosed or inadequately treated hypertensive individuals and referring them for further evaluation, although such a screening program would have a high false-positive rate," Karras et al conclude.

Heartwire from Medscape © 2005 

Cite this: Undiagnosed hypertension is common among urban emergency room patients - Medscape - Sep 02, 2005.