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Proton pump inhibitors are associated with an increased risk of acute kidney failure and acute interstitial nephritis in older patients


Older patients prescribed proton pump inhibitors (PPIs) were more than twice as likely to be hospitalized for acute kidney failure relative to individuals not prescribed these drugs, new research has found.

Researchers at the Institute for Clinical Evaluative Sciences (ICES) and St. Michael’s Hospital looked at patients 66 years and older who were prescribed PPIs and compared their risk of acute kidney failure and acute interstitial nephritis (a type of acute kidney injury often resulting from a drug reaction) within 120 days of starting treatment, to a highly similar group of individuals who were not prescribed these drugs.

PPIs reduce the amount of acid made by the stomach and are used for treating conditions such as heartburn and ulcers. While acute kidney failure is a rare side effect of PPIs, it is important to note that tens of millions of patients take these drugs every year in North America.

“Our study should not deter clinicians from prescribing PPIs for patients with well-defined indications, but underscores the importance of ongoing efforts to curtail the indiscriminate use of these drugs,” said Dr. Tony Antoniou, a pharmacist in St. Michael’s Department of Family and Community Medicine, an adjunct scientist at ICES and lead author of the study published today in CMAJ Open.

Acute kidney failure occurs when kidneys suddenly become unable to filter waste products from the blood. Acute kidney failure can be fatal and requires intensive treatment. However, it may be reversible.

The population-based study identified 290,592 patients who began treatment with a PPI and an equal number of matched unexposed patients. Acute kidney failure occurred in 1,787 individuals within 120 days of the initial prescription date.

“Clinicians should maintain a high index of suspicion for acute interstitial nephritis among patients treated with proton pump inhibitors who present with a decline in renal function, particularly at the outset of treatment,” added Antoniou.

“Proton pump inhibitors and the risk of acute kidney injury in older patients: a population-based cohort study,” was published today in CMAJ Open.

Author block: Tony Antoniou, Erin M. Macdonald, Simon Hollands, Tara Gomes, Muhammad M. Mamdani, Amit X Garg, J. Michael Patterson, David N. Juurlink for the Canadian Drug Safety and Effectiveness Research Network.

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.

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St. Michael’s Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future healthcare professionals in more than 23 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, and care of the homeless are among the hospital’s recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Center, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael’s Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.



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