Hospitals across the country are increasingly turning to hydromorphone over morphine to treat pain, triggering an increase in opioid-related adverse events and higher readmission rates, new research has found.
At a time when there is growing concern about opioid abuse, hospitals are increasingly embracing a much more powerful painkiller without clear benefits, explained Padma Gulur, MD, lead study author, of the Department of Anesthesiology and Perioperative Care at the University of California, Irvine.
Researchers from the Massachusetts General Hospital (MGH), in Boston, launched the study after noticing a four- to fivefold increase in the amount of narcotics being prescribed for pain. They examined data gathered in the University Health Systems Consortium from 38 hospitals covering more than 1.3 million patients who were given either hydromorphone or morphine. The goal was to determine whether opioid choice influenced outcomes.
The initial assumption was that MGH physicians were simply being more aggressive in treating pain. The researchers decided to look at whether the shift to hydromorphone resulted in better patient outcomes, as measured by readmission rates and other benchmarks. They found that hospital use of hydromorphone rose 17% and 22% among medical and surgical patients, respectively, from October 2010 to September 2013.
“We weren’t doing well in any of those columns, and that meant a deeper dive,” Dr. Gulur said. “We had changed from being primarily a morphine hospital to a hydromorphone hospital.”
This change is significant given that “morphine has been traditionally considered the first-line drug for analgesia in hospitals,” the authors noted.
The researchers found that while side effects for both medications were roughly equal, patient outcomes were actually better in some key areas for those who received morphine. The percentage of patients experiencing an adverse event after being given hydromorphone was significantly higher for both surgical and medical patients.
The difference was most pronounced with surgical patients, with 2.19% experiencing an adverse event after taking hydromorphone compared with 1.58% of those who received morphine.
For medical patients, 1.11% had an adverse event after hydromorphone was administrated, compared with 0.86% for morphine patients, the study found.
Patients were considered to have experienced an adverse event if they required naloxone on the same day after receiving either hydromorphone or morphine.
Readmission rates were also markedly lower for morphine patients. More than 10% of medical patients and 4.8% of surgical patients given hydromorphone were readmitted to the hospital within 30 days, compared with 6.5% and 3.5%, respectively, for patients administered morphine.
Still, patients receiving hydromorphone spent somewhat less time in the hospital, with medical patients leaving on average after 5.68 days and surgical patients after 6.21 days. For morphine patients, those numbers were 6.56 and 6.83 days, respectively.
Dr. Gulur said factors such as a greater emphasis on treating pain—from organizations such as the Joint Commission and the U.S. Department of Veterans Affairs—and a general belief in health care that morphine has worse side effects, including nausea and itching, have contributed to the boost in hydromorphone use versus morphine. However, these assumptions are not backed by the latest research, according to Dr. Gulur, who cited the following studies:
- A meta-analysis found no significant differences between the two pain medications in three common side effects: nausea, vomiting and itching (Br J Anaesth2011;107:319-328).
- A systematic review of studies on hydromorphone for acute and chronic pain found “that there is little difference between hydromorphone and other opioids in terms of analgesic efficacy, adverse effect profile and patient preference.” (J Pain Symptom Manage2003;25:169-178).
“There is really no benefit here, and potentially the downside is that we are using stronger and more potent opioids and contributing to the opioid tolerance in our society,” said Dr. Gulur. The findings were presented at the Regional Anesthesiology and Acute Pain Medicine’s 2015 annual meeting.
Study Preliminary, However
However, Jianren Mao, MD, PhD, chief of the Division of Pain Medicine at MGH, expressed reservations about coming to any conclusions on hydromorphone based on the study.
Dr. Mao called the study “very preliminary,” arguing that various clinical conditions, a history of opioid abuse and a myriad of other factors were not considered. He said comparing morphine and hydromorphone is like “comparing apples and oranges.” However, Dr. Mao said he wouldn’t “totally dismiss the concept” that different opioids may “have different outcomes.”
“The notion is certainly a valid notion and worthy of study,” he said.
Dr. Gulur said comparing hydromorphone and morphine is not a new concept, with a range of studies looking at everything from analgesia to side effects. In respect to her own study, Dr. Gulur noted that in “observational studies of this nature, there are inherent limitations in drilling down to individual risk factors.” That said, the large sample in the well-respected University Hospitals database provides “reasonable indicators of population effectiveness, safety and utilization.”
“It is definitely our hope that this will be examined further in future research,” Dr. Gulur said.