Roughly 70% of older adults who experience a hip fracture need post-acute care, typically in a rehabilitation or skilled nursing facility (SNF). Because hip fractures are painful and Medicare data rarely reveals medication use in rehabilitation settings, Brown researchers conducted a study to understand which drugs patients use during recovery and their associated risks.
Led by Kaley Hayes, associate director of pharmacoepidemiology within the Center for Gerontology and Healthcare Research at Brown, the research team worked with Omnicare, a large pharmacy that serves SNFs. Researchers obtained Omnicare’s pharmacy dispensing data and linked it anonymously to Medicare records for people who had hip fractures. This allowed them to comprehensively characterize which pain medications patients received during their rehabilitation stays after hip-fracture surgery.
“Our first finding, which may sound simple but is actually quite important, is that about 84% of people with a hip fracture received some form of pain medication,” Hayes said. “The medications ranged from over-the-counter drugs like acetaminophen to opioids such as hydrocodone and oxycodone. Within three months after a hip fracture, most patients had at least one pain medication prescribed.”
The team’s second key finding was that opioids were frequently prescribed, with the most common regimen being a combination of acetaminophen and hydrocodone, followed by acetaminophen and oxycodone. While these were the predominant pain treatments, there was substantial variation in how individual patients were managed.
Finally, researchers looked at whether pain management during this period might expose patients to potential drug-drug interactions. One important example involves gabapentin, which was originally developed to treat nerve pain but is now often used for a wide range of pain conditions. “We found that about 90% of patients taking gabapentin were also taking an opioid at the same time,” Hayes said. “That’s concerning because this combination can increase the risk of respiratory depression—a known side effect of opioids—and in rare cases, can raise the risk of overdose.”
Hayes, who is assistant professor of epidemiology and of health services, policy and practice, points to several incentives for the co-prescribing of gabapentin and opioids. First, prescribers often view the former as a low-risk or ‘opioid-sparing’ medication, meaning that they believe by using gabapentin, they might be able to reduce or even avoid opioid use. Gabapentin is also often seen as part of a ‘multi-modal’ approach to pain management, which involves using multiple strategies, both pharmacologic and non-pharmacologic, to control pain.
