“[T]here appears to be little evidence that changing opioid prescribing practices immediately after surgery is likely to decrease long-term opioid use. […] [T]he statistical power inherent in [big data] does not directly translate to clinically meaningful differences.”
As many as 300 million surgical procedures are performed annually, making surgical therapy, and related perioperative management, a clear contributor to public and population health. Concurrently, management of the opioid epidemic has emerged as a top public health priority, especially in the United States and Canada, where per capita prescription opioid use substantially exceeds the global average. While any direct link between perioperative opioid prescribing and population-level opioid misuse is complex, as opioids are routinely prescribed for postoperative pain management, anesthesiologists can have a role to play in opioid stewardship. As previously discussed in detail in the journal, the relationship between opioid prescribing practices and public health implications of the opioid epidemic exists within a multifaceted ecosystem.1 Ultimately, the interplay between provider behaviors (driving opioid supply), patient behaviors (driving demand), and the disposal rate of unused opioids impacts the overall pool of opioids in our communities. Shrinking the size of this opioid pool may represent a key opportunity to improve opioid-related public health.1 Therefore, if perioperative clinicians can change prescribing behaviors to appropriately decrease supply, while optimizing patients’ care and experience to manage demand, reductions to the opioid pool could be achieved.
In the current issue of Anesthesiology, Cen and colleagues assess the possible link between early perioperative opioid prescribing patterns of orthopedic surgeons and long-term receipt of opioids.2 Such studies can help to inform how to balance the needs of individual patients with the health of populations in an evidence-based manner. The study objective was to estimate whether variation in surgeons’ opioid prescribing patterns in the week before and after surgery (i.e., the immediate perioperative period) was associated with long-term differences in opioid utilization. The authors hypothesized that if higher-intensity opioid-prescribing surgeons’ patients were more likely to remain on opioids long-term, such findings could inform guidelines and policy approaches to mitigate the risks associated with opioid prescribing. Using Medicare data in a population-based, retrospective cohort design, Cen and colleagues identified more than 600,000 knee replacement patients from 2011 to 2016.
Findings demonstrated that surgeons in the highest quartile of perioperative opioid prescribers (“high-intensity prescribers”) prescribed about 7 mg/day more morphine equivalents immediately before and after surgery than the average surgeon, after adjustment for patient characteristics, and prescribing variation was present.2 The study did not find a clinically meaningful association between receiving care from a higher-intensity perioperative opioid prescriber with opioid receipt in the subsequent 3 months. Patients of higher-intensity prescribers received roughly 2 mg/day morphine equivalents above the mean rate of 10 mg/day. In the 9 months after surgery, patients of higher-intensity perioperative prescribers had lesser daily average opioid prescription (1 mg below the mean of 5 mg/day), which was again not clinically meaningful. While some readers may see the small P values (both less than 0.001) accompanying these results and identify their statistical significance, both estimates amounted to less than a tablet difference per day, highlighting that the statistical power inherent in routinely collected health care databases (often referred to as “big data”) does not directly translate to clinically meaningful differences.
How can these findings guide improvements in opioid-prescribing practices for surgical patients? First, we must acknowledge that high variation in early postoperative opioid prescribing is well documented between different clinicians, hospitals, and even countries.3–5 Such variation appears to be a major perioperative supply side contributor to the opioid pool and has made postoperative prescribing practices a key target for improvement.1 Implementation and evaluation of interventions now demonstrate that standardizing postoperative prescription practices, including limiting the number of days and tablets provided, can effectively reduce opioid dispensation without signals of patient harm.6,7 Such efforts highlight the positive impact that perioperative clinicians have already had on reducing supply side contributions to the opioid pool, and must continue to spread. Based on the findings of Cen and colleagues,2 there appears to be little evidence that changing opioid prescribing practices immediately after surgery is likely to decrease long-term opioid use.
To better address the patient side of the prescription opioid ecosystem, we need future research to move beyond the limitations inherent in studies that use big data. While a strength of such studies is the use of core variables that are accurately captured (i.e., surgery performed, physicians involved, and prescriptions filled), these variables, especially as they pertain to long-term opioid use, often do not capture the complex and patient-centered aspects of pain management that matter most.8 Furthermore, depending on how long-term opioid use is defined, estimates can vary by an order of magnitude.9 We must also recognize that a small but meaningful number of patients (less than 2% based on recent data4,5 ) go on to continue long-term opioid therapy. While anesthesia practice can influence early postoperative pain, and potentially longer-term pain trajectories, the majority of persistent opioid prescribing occurs in primary care, outside of the purview of anesthesiologists, highlighting the need to address opioid prescribing at the health system level.
How can anesthesiologists work to prevent patients from developing long-term pain and opioid use, which directly impact demand-side considerations of the opioid pool? We need to identify which patients are most likely to develop long-term postoperative pain. A key consideration will be a shift from studying routinely collected proxies of persistent pain (such as opioid prescriptions) to patient-centered and -reported outcomes that can capture both benefits and harms of analgesics in terms of function, quality of life, and disability. Core outcome sets in pain and perioperative medicine can guide selection of appropriate measures to ensure that these needed developments are evaluated in a manner meaningful to patients.10,11 Potentially promising interventions include transitional pain services,12,13 but substantial work remains to develop and evaluate such programs. We must also recognize that for some patients, opioids may represent a rational treatment option that may help them to maintain or improve function and quality of life without unacceptable adverse effects.
Ultimately, evidence-based pain management informed by patient characteristics, preferences, and goals should exist. In many ways, this reflects the art of medicine. At a health system level, science now demonstrates that large variation in early postoperative prescribing is an important target to decrease opioid supply, and that reducing variation is achievable and could reduce the pool of opioids in our community. However, scientific efforts to date have consistently demonstrated that this early variation is not meaningfully associated with longer-term opioid use. Therefore, we must continue to focus on the health care system, and opportunities in the perioperative and transitional periods, to improve long-term pain management in a patient-centered and evidence-based manner.
Dr. McIsaac receives salary support from the Ottawa Hospital Anesthesia Alternate Funds Association and a Clinical Research Chair from the University of Ottawa Faculty of Medicine (Ottawa, Canada). Dr. Ladha is supported in part by a Merit Award from the Department of Anesthesiology and Pain Medicine at the University of Toronto (Toronto, Canada) and is co-principal investigator of an observational study on medical cannabis funded by Shoppers Drug Mart (Toronto, Canada).