Severe hypertension: a third have end-organ damage.

Clinical bottom line (level 2c)

  1. Around 3% of Caucasian patients attending a medical emergency department have a diastolic blood pressure of 120 mmHg or more.
  2. ~ 1% have evidence of end-organ damage; commonly stroke (24%), acute pulmonary oedema (22%), hypertensive encephalopathy (17%).
Zampaglione et al: Hypertension 1996; 27 (1): 144-147
Expires September 2004

The study

Outcome study with objective outcomes, not adjusted for confounding factors, not validated in an independent set of patients.

Setting: medical section of emergency department, acute hospital, Italy

449 patients (aged mean 64 years, 58% female) with diastolic blood pressure > 120 mmHg or more and one of:
  • hypertensive emergency: associated evidence of end-organ damage: hypertensive encephalopathy; stroke (cerebral infarction or intracerebral or subarachnoid haemorrhage); acute pulmonary oedema, congestive heart failure, left ventricular failure or aortic dissection; acute MI or unstable angina; progressive renal insufficiency; eclampsia
  • hypertensive urgency: no end-organ damage


Excluded if
  • <18 years old
  • diastolic blood pressure <120 mmHg


    • Most patients had blood and urine chemistry, fundoscopy, ECG, chest X-ray, and CT or ultrasound scan as required. Blood pressure was taken by mercury sphygmomanometer twice in the recumbent position. Average of two readings taken 30 seconds apart were used. Patients were monitored in the emergency department for at least 24 hours, and treated with nifedipine, captopril, clonidine, sodium nitroprusside or frusemide as required.


    Outcomes studied:
  • hypertensive crises
  • hypertensive urgencies
  • hypertensive emergencies
  • end-organ damage associated with hypertensive emergencies: cerebral infarction
  • acute pulmonary oedema
  • hypertensive encephalopathy
  • acute congestive heart failure
  • acute MI or unstable angina
  • intracranial haemorrhage or subarachnoid haemorrhage
  • eclampsia
  • aortic dissection

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    hypertensive crises ? 449/14209 3.2%
    (2.9% to 3.4%)
    hypertensive urgencies ? 341/14209 2.4%
    (2.1% to 2.7%)
    hypertensive emergencies ? 108/14209 0.8%
    (0.6% to 0.9%)
    end-organ damage associated with hypertensive emergencies: cerebral infarction ? 26/108 24%
    (16% to 32%)
    acute pulmonary oedema ? 24/108 22%
    (14% to 30%)
    hypertensive encephalopathy ? 18/108 17%
    (9.6% to 24%)
    acute congestive heart failure ? 15/108 14%
    (7.4% to 20%)
    acute MI or unstable angina ? 13/108 12%
    (5.9% to 18%)
    intracranial haemorrhage or subarachnoid haemorrhage ? 5/108 4.6%
    (0.7% to 8.6%)
    eclampsia ? 5/108 4.6%
    (0.7% to 8.6%)
    aortic dissection ? 2/108 1.9%
    (0.0% to 4.4%)

    • There were 14, 207 admissions to the emergency department. Medical urgencies/ emergencies (any critically ill patient): 1634 (11.5%).

    Comments

    1. US Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure recommends immediate reduction of blood pressure in patients with hypertensive emergencies, and a reduction over 24 hours in patients with hypertensive urgencies.
    2. This study has limited applicability in other populations since only Caucasian patients comprised the study group. In addition,the emergency department has low volume and patients may not be representative of other regions
    3. Patients with hypertensive emergencies were older than those with urgencies.
    4. Patients with strokes, subarachnoid and intracerebral haemorrhages were included. No details on whether symptoms predated ischaemic event.

    Citation

    1. Zampaglione B, Pascale C, Marchisio M, et al: Hypertensive urgencies and emergencies: prevalence and clinical presentation. Hypertension 1996; 27 (1): 144-147
    Contributor: Nick Shenker and Chris Ball, September 2000
    Reviewer: Janice L Zimmerman

    Clinical Question.
    Patient severe hypertension
    Intervention or Exposure prevalence
    Outcome end-organ damage