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Majority of patients who end up in emergency room after a self-measurement for high blood pressure get discharged


The number of patients who turn up in the emergency room (ER) with elevated blood pressure has been on the rise for the last decade and according to a new study by researchers at the Institute for Clinical Evaluative Sciences (ICES), most of those patients are discharged home.

“Guidelines began recommending the use of self-measurement blood pressure devices in the early 2000s. Anecdotally, many emergency physicians report seeing a large increase in the number of patients they see in the ER after the patient received an elevated blood pressure reading at home or in a pharmacy, but most of these patients reported they either had no symptoms or mild symptoms. But the actual numbers have never been studied before,” says Dr. Clare Atzema, lead author on the study, scientist at ICES and emergency department physician at Sunnybrook Health Sciences Centre.

The study, published in Annals of Emergency Medicine, is the first to examine the number of patients who present at an ER after taking a self-measurement blood pressure test.

The study looked at ER visits for high blood pressure at five Ontario emergency rooms from April 2010 and March 2011. In half of the 1508 patient charts it was documented that the patient had taken a self-measurement blood pressure device reading prior to coming to the ER; 40.9 per cent of the 1508 patients had taken a home blood pressure reading, while 8.3 per cent had taken a reading at a pharmacy (total 49.2 per cent).

Among the patients who presented at an ER following a self-measurement blood pressure device reading, the overwhelming majority (97 per cent) were discharged back home at the end of the emergency visit. This compares to 11.2 per cent for the rest of the patients.

“To provide context, among all emergency patients seen in Ontario, 90 per cent are discharged, and in patients with another ambulatory-sensitive cardiovascular disease, atrial fibrillation, 63 per cent are discharged. Therefore 97 per cent is an extremely high rate of discharge and a very low rate of hospital admission,” adds Atzema.

Previous research by this group shows that the number of ER visits for which high blood pressure was the primary diagnosis jumped 64 per cent in the last decade, from 15,793 to 25,950.

The researchers add that the high rates of discharge suggest that many patients who present for emergency care after taking a home or pharmacy blood pressure test may not require emergency care, but instead could be provided care at a timely appointment with their primary care provider.

Author block: Atzema CL, Wong A, Masood S, Zia A, Al-bulushi S, Sohail QZ, Cherry A, Chan FS.

The article “The characteristics and outcomes of patients who make an emergency department visit for hypertension after use of a home or pharmacy blood pressure device,” is published July 20, 2018 in the Annals of Emergency Medicine.

The Institute for Clinical Evaluative Sciences (ICES) is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy. For the latest ICES news, follow us on Twitter: @ICESOntario

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Deborah Creatura
Media Advisor, ICES
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