Nonadherence to Clinical Practice Guidelines for Opioid Prescribing in Patients with Chronic Low Back Pain: A Pain Research Registry–Based Study

Discussion

Almost one-fifth of participants who were prescribed opioids for low back pain did not receive them in a manner that was adherent to CPGs in the United States. Such participants used neither nonpharmacological treatments nor NSAIDs before using opioids for treatment of their chronic low back pain, contrary to recommendations from the Centers for Disease Control and Prevention³ and the American College of Physicians.⁴ These participants experienced worse clinical outcomes than their counterparts who used opioids in accord with CPGs, as manifested by greater low back pain intensity, back-related disability, and pain impact on health-related quality of life. The 2 latter findings surpassed the threshold for a medium effect size (Cohen's d ≥ 0.5). Thus, the study findings suggest that important health benefits may derive from adherence to major clinical practice guidelines for chronic low back pain in the United States.^3,4 Although several sociodemographic, psychological, and clinical characteristics were associated with nonadherence to CPGs in univariate analyses, only having a low educational level or being 60 years of age or older, male, or bothered a lot by widespread pain remained significantly associated with nonadherence to CPGs in the multivariate analysis.

Most importantly, having intermediate or higher levels of education were strongly and inversely associated with nonadherence to CPGs in this study. Alternatively, having no more than a high school education was an important risk factor for nonadherence to CPGs. Over the past 2 decades, several organizations in the United States have highlighted that only a small proportion of the population is sufficiently proficient in health literacy to understand opioid contracts or such related items as patient educational materials and informed consent documents.¹⁵ The National Pain Strategy now envisions that patients with low literacy or communications disabilities would have access to information that they can understand about the benefits and risks of treatment options, including opioids.¹⁶ Correspondingly, the Federal Pain Research Strategy endorses public health strategies to educate patients on managing pain, including health literacy.¹⁷ Although the association between low literacy and opioid use may be potentially confounded by other variables not controlled in our study, the findings generally support greater efforts to mitigate the impact of opioid use that is not adherent to CPGs among patients with low educational levels.

It is interesting to note that most aspects of the participant interaction with their physician, including satisfaction with the technical quality of the physician, were not associated with CPG adherence status. Only the patient participation and patient orientation scale of the Communication Behavior Questionnaire demonstrated a marginally significant statistical association with nonadherence to CPGs. Participants who received care for chronic low back pain that was nonadherent to CPGs rated their physicians more highly on this scale. This may simply represent a type I error attributable to the multiple physician interactions studied herein. However, several items on the patient participation and patient orientation scale focus on the degree to which the physician discusses and explains treatment options, involving the patient in a collaborative manner. It remains unclear if such patient involvement facilitates physician deviation from CPGs. Recent research has shown that patients on long-term opioid therapy for chronic noncancer pain report significantly lower satisfaction with their pain treatment when opioids are discontinued.¹⁸

Our study findings are consistent with the belief that reducing pain intensity through opioid prescribing should not be the ultimate goal of chronic pain management. Opioid prescribing that was not adherent to CPGs may have represented failed efforts to eliminate or minimize chronic pain among the participants in our study. Such opioid prescribing may have adversely selected for patients who were least likely to benefit and most likely to be harmed by opioids.¹⁹ Patient functioning and health-related quality of life may be more appropriate clinical endpoints in the management of chronic low back pain.

There were several strengths of our study. It was conducted within a pain research registry using a digital platform that enhanced and facilitated participation, particularly since the onset of the COVID-19 pandemic in March 2020. This digital research platform also precluded missing data in any of the research instruments used by the registry.⁶ The registry used methods recommended by the National Institutes of Health Task Force on Research Standards for Chronic Low Back Pain.⁵ These included the diagnostic criteria for chronic low back pain, use of the RMDQ as a legacy measure of back-related functioning, and quantifying the impact of low back pain on health-related quality of life. The study was conducted after the Centers for Disease Control and Prevention Guideline for Prescribing Opioids for Chronic Pain was published.³ Although there is often a lag time between guideline publication, dissemination, and implementation, it is important to note that substantial efforts were undertaken during 2016 to address the “opioid crisis” and hasten implementation of the Centers for Disease Control and Prevention guideline. For the first time in the 145-year history of the Office of the Surgeon General, a letter was mailed specifically to medical professionals (including 2.3 million doctors, nurses, dentists, and other clinicians) calling them to action in ending the opioid epidemic through the Turn The Tide Rx program.²⁰ The letter included a pocket card for prescribing opioids for chronic pain as part of the program. Thus, physicians should have been well aware of opioid prescribing guidelines during the entire study period.

There were also limitations that should be noted because this was a cross-sectional study using only participant-reported data collected at the initial registry encounter to measure the prevalence of nonadherence to CPGs. It is possible that some participants may not have recalled use of nonpharmacological treatments or NSAIDs before using opioids for low back pain. It was not possible to assemble a sufficiently large cohort of opioid-naïve participants for meaningful longitudinal follow-up over 12 months of registry observation. Thus, the temporal relationships among measures were not always clear. For example, we may have underestimated nonadherence to CPGs by identifying only prevalent cases at the initial registry encounter. Incident cases of nonadherence to CPGs that occurred before registry enrollment would have been left-censored if the participant subsequently initiated use of a nonpharmacological treatment or NSAID after using opioids, but before enrollment. Alternatively, we may have overestimated nonadherence to CPGs because we collected data on only 6 common nonpharmacological treatments for low back pain. It is possible that participants may have used other less common nonpharmacological treatments, including those not shown to be effective,^4,21 before initiating opioids.

In summary, our study findings suggest that up to 1/5^th of patients with chronic low back pain in the United States may be prescribed opioids in a manner that is not adherent to CPGs, thereby placing them at risk for poor outcomes involving low back pain intensity, back-related disability, and pain impact on health-related quality of life. Patients with low educational levels, older persons, males, and those with bothersome widespread pain are at greatest risk of receiving opioids that are not prescribed according to CPGs. Physician characteristics, such as communications with their patients and empathy, and patient satisfaction with physician interactions are generally not associated with CPG adherence status.