(HealthNewsDigest.com) - ROCHESTER, Minn. — Opioid prescriptions from the emergency department (ED) are written for a shorter duration and smaller dose than those written elsewhere, shows new research led by Mayo Clinic. The study, published today in the Annals of Emergency Medicine, also demonstrates that patients who receive an opioid prescription in the ED are less likely to progress to long-term use.

This challenges common perceptions about the ED as the main source of opioid prescriptions, researchers say.

“There are a few things that many people assume about opioids, and one is that, in the ED, they give them out like candy,” says lead author Molly Jeffery, Ph.D., scientific director, Mayo Clinic Division of Emergency Medicine Research. “This idea didn't really fit with the clinical experience of the ED physicians at Mayo Clinic, but there wasn't much information out there to know what's going on nationally.”

To study 5.2 million opioid prescriptions written for acute – or new-onset – pain across the U.S. between 2009 and 2015, the researchers used the OptumLabs Data Warehouse, a database of de-identified, linked clinical and administrative claims information. None of the patients in the study had received an opioid prescription for the previous six months. This made it easier to compare doses by eliminating patients who built up a tolerance to the drugs.

Researchers found prescriptions for commercially insured patients from the ED were 44 percent less likely to exceed a three-day supply than those written elsewhere. Those patients were also 38 percent less likely to exceed a daily dose of 50 milligrams of morphine equivalent, which is almost seven pills of five-milligram oxycodone per day. And they were 46 percent less likely to progress to long-term opioid use. An opioid prescribing guideline from the Centers for Disease Control and Prevention (CDC) issued in 2016 cautions against exceeding a three-day supply or 50 milligrams of morphine equivalent per day for acute pain.

The results were similar for Medicare patients.

“As an emergency physician, it was a good surprise to see the results of the study,” says senior author M. Fernanda Bellolio, M.D., research chair of the Mayo Clinic Department of Emergency Medicine.

Also unexpected, the researchers say, were the number of prescriptions that exceeded 50 milligrams of morphine equivalent per day. One in 5 commercially insured patients in a non-ED setting received a dose exceeding this guideline. People receiving prescriptions exceeding CDC recommendations – regardless of where they were written – were three times more likely to progress to long-term use.

“Patients and physicians should be aware of the risk of long-term use when they're deciding on the best treatment for acute pain,” Dr. Bellolio says.

The researchers hope this study will help combat what the CDC calls an opioid epidemic by working toward an ideal prescription to match each patient’s need.

“There is a large amount of variability across patient populations in the amount of opioids people receive for acute pain, depending on where they receive their prescription,” Dr. Jeffery says. “When we see variability on such a large scale, we should worry that some people are not getting the best, most appropriate treatment.”

In the last 15 years, the number of Americans receiving an opioid prescription and the number of deaths involving overdoses have roughly quadrupled, according to the CDC. More than 41 people per day died from a prescription opioid overdose in 2015.

The researchers also note a positive trend: The proportion of prescriptions progressing to long-term use dropped over the study’s period.

The team now is studying what’s driving the differences between ED prescriptions and other practice settings. They hope shedding light on why there’s a difference will reduce the variation in prescriptions and help health care providers determine the best treatment for each individual.

The Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery funded the research. The center works within the medical practice, gathering and analyzing data with the goal of making broad-based quality and efficiency improvements in patient care at Mayo and beyond.

Dr. Jeffery is a health care practice and policy researcher in the Mayo Clinic Kern Center for the Science of Health Care Delivery, and Dr. Bellolio is a Kern Health Care Delivery Scholars Program alumna.

Their co-authors are:

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