Severe acute hypertension among inpatients admitted from the emergency department

Abstract

Background: Hospitalists often treat patients with severe acute hypertension (AH) presenting to the hospital. Little is known about the epidemiology of this syndrome.

Objective: To examine the prevalence of severe AH in patients admitted through the emergency department (ED) and its associated outcomes.

Design: A cohort study using retrospectively collected vital signs and other clinical data.

Patients: A total of 1,290,804 adults admitted between 2005 and 2007.

Setting: One hundred fourteen acute-care hospitals.

Measurements: Severe AH was defined as at least 1 systolic blood pressure (SBP) >180 mmHg. We used multivariable regression to estimate AH-attributable in-hospital mortality, need for mechanical ventilation (MV), and length of stay (LOS).

Results: Severe AH occurred in 178,131 (13.8%) patients. Disease categories with the highest prevalence were nervous (29.0%), circulatory (16.0%), endocrine (14.7%), and kidney/urinary (13.5%). The overall in-hospital mortality was 3.6%. The relationship between severe AH strata and mortality was graded for nervous system diseases; mortality rates for each 10 mmHg increase in SBP from 180 to >220 mmHg were 6.5%, 8.1%, 9.9%, 12.0%, and 19.7%, respectively (P < 0.0001). The relationship between severe AH strata and need for MV was graded in the most pronounced way in respiratory and circulatory conditions (P < 0.0001). The relationship between severe AH strata and LOS was graded in most disease categories (P < 0.0001).

Conclusions: Severe AH appears common and its prevalence varies by underlying clinical condition. Severe AH is associated with excess in-hospital mortality for patients with nervous system diseases and, for most disease categories, prolongs hospitalization.