The official sum of opioid-related settlements reached between U.S. state and local governments and the major pharmaceutical opioid manufacturers, marketers, distributors and retailers .
Stark statistics from the U.S. Centers for Disease Control and Prevention also indicate that since 1999, approximately 860,000 people have died from an opioid overdose, with nearly 318,000 of those deaths attributable to prescription opioids. In 2024, 73.4 percent of drug overdose deaths were attributable to opioids, with 65.1 percent of those deaths from illegally made fentanyls, .
While much of the focus of the opioid litigation and public conversation in recent years has been on the role of the pharmaceutical industry and how their advertising campaigns led to an increase in opioid use and subsequent overdose deaths, there is more to the story behind this nationwide catastrophe.
Researchers at the University of Notre Dame found that doctors had a hand in fueling the opioid crisis by aggressively prescribing opioids to treat chronic pain. Their work shows the extent to which doctors鈥� prescribing practices can be linked to that increase, indicating that if there had not been such a strong push on the part of physicians, opioid-related death rates would have been much lower.
According to and , both from Notre Dame鈥檚 and co-authors of an , physicians began prescribing opioids to treat chronic pain more extensively and more often in the late 1990s. If their prescription practices had stayed at their 1995 levels, there would have been 43 percent fewer deaths by 2015, just two decades later.
The duo鈥檚 work has the potential to guide conversations about reeducating doctors on the appropriate use of opioids for pain relief and reframing how medical schools teach future doctors about appropriate prescribing practices.
鈥淢ost of the people who have followed this issue acknowledge that the changing prescribing practices of doctors played a critical role in the drug crisis,鈥� said Evans, the Keough-Hesburgh Professor of Economics and co-founder of Notre Dame鈥檚 鈥淚 think we鈥檝e come up with a nice way to quantify the impact, and it is massive.鈥�
To track physicians鈥� practice of overprescribing opioids as pain medication, Evans and Lieber first examined the county characteristics in 1990 that predicted the surge in drug deaths beginning in the early 2000s. They identified one factor that is particularly predictive for whether the county will eventually have a severe drug poisoning crisis: the fraction of the working age population receiving Social Security Disability Insurance (SSDI).
These benefits are for adults who have worked for a minimum of time in jobs covered by Social Security and who have a medical condition limiting their ability to maintain gainful employment. The co-authors showed that not only are those on SSDI in more pain than average, but those in high SSDI rate geographies also have higher levels of pain. Their work shows that as physicians became more aggressive at treating chronic pain with opioids, these high-SSDI, high-pain areas had, on average, a much more severe drug poisoning crisis.
Historically, opioids had only been prescribed for those post-surgical and cancer patients experiencing acute pain, leaving those with chronic pain untreated. Starting in the mid-1990s, however, there was a reevaluation of the use of opioids to treat chronic pain. In 1995, the co-authors noted, the medical community established the notion that pain was the 鈥渇ifth vital sign,鈥� specifically measuring pain levels and equating pain relief with quality of care. In that same year, medical experts released a statement advocating the use of opioids for chronic pain relief. As a result, physicians took note and became more aggressive in their prescribing of those drugs.
Using data from the National Ambulatory Medical Care Surveys from 1980 through 2015, Evans and Lieber demonstrated that prior to 1995, only about 7 percent of patients visiting a doctor with a condition likely to generate chronic pain received an opioid prescription. After 1995, this number increased dramatically, reaching 25 percent by 2015.
鈥淲e were struck by how much these numbers changed over time and how the timing coincided with the efforts to encourage greater use of opioids to treat chronic pain,鈥� said Lieber, the Dillon Hall Associate Professor in Notre Dame鈥檚 .
Evans added that the dropped the use of pain as the fifth vital sign in 2016, noting that 鈥渢he president of the AMA said at the time that physicians played a key role in the epidemic and now they must do their part to end it.鈥�
The study takes into account other factors that potentially drive drug poisoning death rates such as local economic conditions, general access to health services, the decline of institutions like manufacturing jobs and relationships, the rise and marketing of opioid drugs like OxyContin, and prescription drug monitoring programs.
A key data set in their work was the Drug Enforcement Administration鈥檚 Automation of Reports and Consolidated Orders System (ARCOS), which tracks shipments of opioids from manufacturers to points of sale or distribution. Detailed transaction-level data from ARCOS was released as part of the opioid litigation.
In 2024, Notre Dame developed a user-friendly interface of the ARCOS database, which enables public access to more than 10 years of national controlled substance transaction information for 14 different opioids.
This research stems from the , a data-focused research effort fostering and advancing multidisciplinary work on a wide range of pressing demographic issues facing society. Evans leads ND Pop, which is facilitated by a partnership between the University鈥檚 and the .
To hear Evans and Lieber discuss their research, check out the , hosted by the Hoover Institution.
Contact: Tracy DeStazio, associate director of media relations, 574-631-9958 or tdestazi@nd.edu