Opioid prescribing practices put patients at risk, study finds

Some family physicians write dramatically higher numbers of prescriptions for powerful opioid painkillers than others, according to a new study that warns major problems with prescribing practices is putting patients at risk.

The study, being published in the March edition of Canadian Family Physician, found family doctors who wrote the most opioid prescriptions also had the highest number of patient deaths linked to the painkillers.

Opioids are a class of drugs used most commonly to treat and manage pain. They have come under intense scrutiny in recent years, however, as use of the drugs increased significantly and more patients abused, misused or overdosed on the drug.

The findings add to widespread concerns in the medical community that opioid painkillers, such as oxycodone, morphine and fentanyl, are being over-prescribed, leading to drug dependence and serious side effects, including increased risk of death.

"They're dangerous drugs," said Irfan Dhalla, staff physician and scientist at Toronto's St. Michael's Hospital and lead author of the study. "They need to be prescribed and used with great care and the way they're being used right now, they're often prescribed and used as if they were much safer than they are."

But the study also highlights divisions in the medical community about the role opioids should play. While some health professionals want use of the drugs restricted, others say that solution ignores the fact opioids are an important treatment tool for some chronic-pain patients.

In the study, researchers at St. Michael's Hospital and the Institute for Clinical Evaluative Sciences used records from Ontarians who qualified for provincial drug coverage in 2006 to determine opioid prescribing rates among physicians.

They found major variation among family doctors across Ontario, with some physicians writing opioid prescriptions at rates 55 times higher than those who prescribed opioids the least.

Researchers also determined that of the 408 people whose deaths were linked to opioids in 2006, 166 of them had received at least one publicly funded opioid prescription in the year before their death. About 60 per cent of them received their final prescription from a family physician.

"I think the dangers of these medications are still underappreciated," Dr. Dhalla said.

The study authors argue the number of opioid prescriptions given to patients should be reduced in order to prevent serious adverse events in patients. Dr. Dhalla said there is limited evidence proving the effectiveness of opioids in managing pain, which should provide the impetus for their use to be restricted.

There are some efforts under way to improve opioid prescribing practices in Canada. Guidelines were published last year to help doctors determine the circumstances under which the drugs should be prescribed. Now, the Michael G. DeGroote National Pain Centre at McMaster University in Hamilton is overseeing the guidelines and will update them in the hope they help health professionals across Canada understand opioid use.

Norm Buckley, director of the pain centre and chair of anesthesia at McMaster's medical school, said some patients can benefit from opioid painkillers, which is why doctors need better prescribing guidelines. He added that it might be too simple to conclude the drugs need to be severely limited because some patients died while taking them. Many chronic-pain patients taking opioids, for instance, suffer depression and may commit suicide, not accidentally overdose on the drugs.

"Not prescribing them is as reflective of lack of knowledge and skill as prescribing them might be," Dr. Buckley said.

Dr. Buckley has also conducted research studies for companies that sell opioid drugs.

However, Dr. Irfan argues opioids have clear, undeniable dangers to many patients and that much better evidence is needed to understand who may be most at risk while taking them as well as the long-term side effects.

He said the explosion in the use of opioids is, in many ways, irresponsible and more of a reflection of aggressive marketing by the drug companies that sell them.