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Home blood pressure monitoring may be driving unnecessary visits to ER: study


Visits to Ontario ERs for hypertension grew 64 per cent in 10 years, while mortality remained low

A new study from the Institute for Clinical Evaluative Sciences (ICES) and Sunnybrook Health Sciences Centre suggests that a growing number of people in Ontario make unnecessary trips to the emergency room because of worries about high blood pressure, possibly due to the prevalence of home monitoring equipment.

The researchers found that Ontario emergency department visits with a primary diagnosis of hypertension (commonly known as high blood pressure) increased by 64 per cent over a 10-year period (from 15,793 in 2002 to 25,950 in 2012). However, over 90 per cent of these patients were discharged without admission to hospital, with low rates of hypertensive complications or death.

The study, which was published today in the journal Annals of Emergency Medicine, is the first of its kind to assess population-level outcomes for hypertension.

The authors say the growth in emergency department visits for hypertension may be due in part to the increased use of in-pharmacy or home blood pressure monitoring devices.

“While home blood pressure monitoring is endorsed by all the major guidelines and is a good idea for long-term blood pressure management, our findings show that that this practice may be inadvertently driving unnecessary visits to emergency rooms,” says the study’s senior author Clare Atzema, who is a scientist at ICES and an emergency physician at Sunnybrook Health Sciences Centre.

Among the study’s findings:

  • Less than 10 per cent of emergency visits with a diagnosis of hypertension resulted in admission. The percentage further decreased over the study decade, from 10 per cent in 2002 to 7 per cent in 2012.
  • Mortality following a visit to the ED with a primary concern of hypertension was very low, at only 0.17 per cent within 7 days. Two years following the first visit, mortality was at 4.4 per cent.
  • For the less than 10 per cent of patients who were admitted to hospital after an initial complaint of hypertension, the most frequent diagnoses were renal failure, heart failure or stroke.
  • Residents of the lowest-income neighbourhoods accounted for 23.4 per cent of all 2012 hospital ED visits for hypertension, compared to 16.4 of residents from higher-income neighbourhoods.

The authors say that the low rates of patient mortality and hypertensive complications show that current approaches to hypertension in the province’s emergency departments are working, including keeping admission rates for hypertension low.

However, they say that patients should receive more education about what to do when they get a high blood pressure reading, including when and how to seek emergency care.

Says Atzema, “Patients and their care providers need to know that unless your high blood pressure reading coincides with symptoms, such as chest pain, headache, nausea or shortness of breath, it is generally quite safe to follow up with your family doctor at his or her next available appointment.”

“A population-based analysis of outcomes in patients with a primary diagnosis of hypertension in the emergency department” was published today in the journal Annals of Emergency Medicine.

Author block: Sameer Masood, Peter C Austin, Clare L Atzema.

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

About Sunnybrook – Sunnybrook Health Sciences Centre is inventing the future of healthcare for the 1.2 million patients the hospital cares for each year through the dedication of its more than 10,000 staff and volunteers. An internationally recognized leader in research and education and a full affiliation with the University of Toronto distinguishes Sunnybrook as one of Canada’s premier academic health sciences centres. Sunnybrook specializes in caring for high-risk pregnancies, critically-ill newborns and adults, offering specialized rehabilitation and treating and preventing cancer, cardiovascular disease, neurological and psychiatric disorders, orthopaedic and arthritic conditions and traumatic injuries. The Hospital also has a unique and national leading program for the care of Canada’s war veterans. For more information about how Sunnybrook is inventing the future of healthcare please visit us online at www.sunnybrook.ca


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  • Laura Bristow
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