In recent years, seniors have been five times more likely than other Canadians to be hospitalized due to an adverse drug reaction, according to a new report.
One in 200 seniors was hospitalized because of an adverse drug reaction in 2010–2011, compared with 1 in 1,000 among all other Canadians. This translates to approximately 27,000 people age 65 and older, according to the report, released Tuesday by the Canadian Institute for Health Information (CIHI).
“The factors most often associated with hospitalization for adverse drug reactions are the number of drugs, age, and being hospitalized in the previous year,” said Michael Gaucher, director of pharmaceuticals and health workforce information services at CIHI.
“While it is appropriate in many cases for people to be using these medications, it is important for seniors, their caregivers and health professionals to manage the associated risks.”
Blood thinners, often used to prevent heart attack and stroke, were the drug class most commonly associated with drug-related hospitalizations among seniors (13 percent), followed by chemotherapy drugs (12 percent) and opioids, a class of strong pain killers (7.4 percent).
The most likely reasons for hospitalization include hemorrhaging from blood thinners, low white blood cell count from chemotherapy drugs, and constipation from opioids.
In some cases, these reactions were related to difficulty determining and maintaining the proper drug dosage, especially among blood thinner and opioid users. Blood thinners are known to have a narrow window between what is an effective or a harmful dose, and opioids tend to require dose adjustments to balance pain relief and unwanted effects, said the report.
Those with multiple chronic conditions who take several drugs simultaneously to manage their illnesses were also more likely to have an adverse reaction.
The report recommended regular reviews of patients’ medications by physicians and pharmacists to reduce the risks of an adverse reaction. It also touted the implementation of drug information systems such as electronic health records, which would help with medication reviews by providing a more complete picture of patients’ medications.
Electronic health records have already been partially completed in several provinces to date, the report noted.
“To minimize your risk of an adverse drug reaction, you should regularly review your medications with your physicians and notify them of any changes in what you are taking,” said Dr. David Hogan, Brenda Strafford Foundation chair in geriatric medicine at the University of Calgary.
“It is also important to follow any plans to monitor therapy—such as getting blood tests—and don’t hesitate to report to your care providers any concerns you might have,” Hogan said.
In an issue of the journal Drug Safety published last year, researchers estimated that emergency department visits and hospitalizations related to adverse drug reactions among seniors in Canada cost an estimated $35.7 million per year.