Notes from the Field: Trends in Gabapentin Detection and Involvement in Drug Overdose Deaths - 23 States and the District of Columbia, 2019-2020

Opioid and non-opioid analgesic regimens after fracture and risk of serious opioid-related events

Background

Non-opioid analgesics are prescribed in combination with opioids among patients with long bone fracture to reduce opioid prescribing needs, yet evidence is limited on whether they reduce the risk of serious opioid-related events (SOREs). We compared the risk of SOREs among hospitalized patients with long bone fracture discharged with filled opioid prescriptions, with and without non-opioid analgesics.

Design

We identified a retrospective cohort of analgesic-naïve adult patients with a long bone fracture hospitalization using the Merative MarketScan Commercial Database (2013-2020). The exposure was opioid and non-opioid analgesic (gabapentinoids, muscle relaxants, non-steroidal anti-inflammatory drugs, acetaminophen) prescriptions filled in the 3 days before through 42 days after discharge. The outcome was the development of new persistent opioid use or opioid use disorder during follow-up (day 43 through day 408 after discharge). We used Cox proportional hazards regression with inverse probability of treatment weighting with overlap trimming to compare outcomes among those that filled an opioid and a non-opioid analgesic to those that filled only an opioid analgesic. In secondary analyses, we used separate models to compare those that filled a prescription for each specific non-opioid analgesic type with opioids to those that filled only opioids.

Results

Of 29 489 patients, most filled an opioid prescription alone (58.4%) or an opioid and non-opioid (22.0%). In the weighted proportional hazards regression model accounting for relevant covariates and total MME, filling both a non-opioid analgesic and an opioid analgesic was associated with 1.63 times increased risk of SOREs compared with filling an opioid analgesic only (95% CI 1.41 to 1.89). Filling a gabapentin prescription in combination with an opioid was associated with an increased risk of SOREs compared with those that filled an opioid only (adjusted HR: 1.84 (95% CI1.48 to 2.27)).

Conclusions

Filling a non-opioid analgesic in combination with an opioid was associated with an increased risk of SOREs after long bone fracture.

Level of evidence

Level III, prognostic/epidemiological.

Study type

Retrospective cohort study.

Complex regional pain syndrome: advances in epidemiology, pathophysiology, diagnosis, and treatment

Complex regional pain syndrome (CRPS) is a rare pain disorder that usually occurs in a limb after trauma. The features of this disorder include severe pain and sensory, autonomic, motor, and trophic abnormalities. Research from the past decade has offered new insights into CRPS epidemiology, pathophysiology, diagnosis, and treatment. Early identification of individuals at high risk of CRPS is improving, with several risk factors established and some others identified in prospective studies during the past 5 years. Better understanding of the pathophysiological mechanisms of CRPS has led to its classification as a chronic primary pain disorder, and subtypes of CRPS have been updated. Procedures for diagnosis have also been clarified. Although effective treatment of CRPS remains a challenge, evidence-based integrated management approaches provide new opportunities to improve patient care. Further advances in diagnosis and treatment of CRPS will require coordinated, international multicentre initiatives.

Direct-To-Definitive Urine and Oral Fluid Test Results for Unscreened and Rarely Screened Drugs in Individuals Applying for Methadone Treatment in 7 U.S. States

The standard protocol in addiction treatment/pain management is to conduct immunoassay screens for major drugs subject to misuse, followed by confirmatory testing of positive results. However, this may miss unscreened or rarely screened drugs that could pose risks, especially to polydrug users. We sought to determine the prevalences of unscreened/rarely screened drugs in a sample of individuals misusing drugs in 7 U.S. states, and to compare the results of urine vs. oral testing for these drugs by direct-to-definitive liquid chromatography/tandem mass spectrometry (LC-MS-MS). The five drugs with the highest prevalences were: gabapentin (16.8%), quetiapine (6.2%), chlorpheniramine (5.3%), hydroxyzine (4.9%), and ephedrine (3.5%). All have clinical significance as indicated by severity of possible side effects, interactions with other drugs, and/or misuse potential. Drugs were generally detected more frequently in oral fluid than urine, but gabapentin was more frequently detected in urine. The prevalences of the included drugs seem high enough, and their clinical significance important enough, to warrant consideration of expanding clinical drug test panels, either by direct-to-definitive testing or the addition of selected immunoassay screens when available. Oral fluid was usually more suitable than urine as the test matrix, given the higher rates of detection in oral fluid for most substances included in this study.

Gabapentin Use Among Individuals Initiating Buprenorphine Treatment for Opioid Use Disorder

Importance

Gabapentin prescriptions have drastically increased in the US due to off-label prescribing in settings such as opioid use disorder (OUD) treatment to manage a range of comorbid conditions and withdrawal symptoms, despite a lack of evidence.

Objective

To assess the purpose and associated risks of off-label gabapentin use in OUD treatment.

Design, Setting, and Participants

This retrospective recurrent-event case-control study with a crossover design used administrative claims data from MarketScan Commercial and Multi-State Medicaid databases from January 1, 2006, to December 31, 2016. Individuals aged 12 to 64 years with an OUD diagnosis and filling buprenorphine prescriptions were included in the primary analysis conducted from July 1, 2022, through June 1, 2023. Unit of observation was the person-day.

Exposures

Days covered by filled gabapentin prescriptions.

Main Outcomes and Measures

Primary outcomes were receipt of gabapentin in the 90 days after initiation of buprenorphine treatment and drug-related poisoning. Drug-related poisonings were defined using codes from International Classification of Diseases, Ninth Revision, and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision.

Results

A total of 109 407 patients were included in the analysis (mean [SD] age, 34.0 [11.2] years; 60 112 [54.9%] male). Among the 29 967 patients with Medicaid coverage, 299 (1.0%) were Hispanic, 1330 (4.4%) were non-Hispanic Black, 23 112 (77.1%) were non-Hispanic White, and 3399 (11.3%) were other. Gabapentin was significantly less likely to be prescribed to Black or Hispanic patients, and more likely to be prescribed to female patients, those with co-occurring substance use or mood disorders, and those with comorbid physical conditions such as neuropathic pain. Nearly one-third of persons who received gabapentin (4336 [31.1%]) had at least 1 drug-related poisoning after initiating buprenorphine treatment, compared with 13 856 (14.5%) among persons who did not receive gabapentin. Adjusted analyses showed that days of gabapentin use were not associated with hospitalization for drug-related poisoning (odds ratio, 0.98 [95% CI, 0.85-1.13]). Drug-related poisoning risks did not vary based on dosage.

Conclusions and Relevance

Gabapentin is prescribed in the context of a myriad of comorbid conditions. Even though persons receiving gabapentin are more likely to have admissions for drug-related poisoning, these data suggest that gabapentin is not associated with an increased risk of drug-related poisoning alongside buprenorphine in adjusted analyses. More data on the safety profile of gabapentin in OUD settings are needed.

Polypharmacy in Multiple Sclerosis: Prevalence, Risks, and Mitigation Strategies

PURPOSE OF REVIEW

Polypharmacy, the use of ≥ 5 medications, is common in people with multiple sclerosis and is associated with negative outcomes. The use of multiple medications is common for symptom management in people with multiple sclerosis, but risks drug-drug interactions and additive side effects. Multiple sclerosis providers should therefore focus on the appropriateness and risks versus benefits of pharmacotherapy in each patient. This review describes the prevalence and risks associated with polypharmacy in people with multiple sclerosis and offers strategies to identify and mitigate inappropriate polypharmacy.

RECENT FINDINGS

Research in people with multiple sclerosis has identified risk factors and negative outcomes associated with polypharmacy. Medication class-specific investigations highlight their contribution to potentially inappropriate polypharmacy in people with multiple sclerosis. People with multiple sclerosis are at risk for inappropriate polypharmacy. Multiple sclerosis providers should review medications and consider their appropriateness and potential for deprescribing within the context of each patient.

Gabapentinoid detection in coronial casework in Gold Coast, Australia: a 5-year retrospective study

Gabapentinoids is a class of drug with analgesic, anxiolytic, and anticonvulsant properties and has a reported increase in prescription, use, and adverse outcomes. Regional studies are scant, and postmortem toxicological data may characterise patterns of regional use and inform local interventions. Characterising drug and non-drug-related deaths with gabapentinoid detection may also aid in toxicology interpretation. A 5-year retrospective study on all deaths admitted to the Gold Coast University Hospital under where toxicological analysis was performed. Of the gabapentinoids, only pregabalin was detected over the study period, and annual rates of detection did not differ significantly over the period (7.4-12.4%). In cases where pregabalin was detected, it was 15 times more likely to be a drug-related death. Drug-related deaths where pregabalin was detected have higher levels of pregabalin, are younger, and had a greater proportion of concurrent opioid detection. Postmortem detection of pregabalin was associated with drug-related deaths. Higher levels, younger decedents, and concurrent use of opioids were found in drug-related deaths. Public health interventions and regulated prescribing to target concurrent pregabalin and opioid use may address the burden of pregabalin drug-related deaths.

Trends in overdose deaths involving gabapentinoids and Z-drugs in the United States

INTRODUCTION

As policies have been implemented to limit access to prescription opioids, other drugs have been prescribed off-label, sometimes concurrently with opioids, to manage pain. There are concerns about the use of gabapentinoids and "Z-drugs" with opioids. As the opioid crisis transitions to illicit opioids and polysubstance use, little work quantifies the concurrent involvement of non-opioid prescription drugs and illicit opioids in overdose deaths.

METHODS

Data from the census of deaths in the United States for 1999-2020 were used to understand trends in deaths involving gabapentinoids/Z-drugs and opioid co-involvement. These trends were studied overall and by sex, race, age, and education.

RESULTS

Per capita overdose deaths involving gabapentinoids/Z-drugs increased almost continuously since 1999, averaging 15.8% annual growth. This rate increased to 32% in 2020, primarily due to overdoses involving synthetic opioids. Women typically had higher rates of overdose deaths involving both opioids and gabapentinoids/Z-drugs, though this disparity disappeared in 2020. White Americans and American Indians/Alaskan Natives historically had higher rates than other racial groups; however, Black Americans experienced over 60% annual growth in recent years. Low education groups have been disproportionately impacted. The age incidence tends to be older than overdoses involving opioids more generally.

CONCLUSION

Overdose deaths involving opioids and gabapentinoids/Z-drugs have tended to disproportionately affect women and older age groups compared to all opioid-involved overdoses. As deaths involving synthetic opioids likely reflect use of illicitly-obtained opioids, there may be less of a role for policies targeting the concurrent prescribing of gabapentinoids/Z-drugs with opioids to reduce these deaths.

Understanding the rise in overdose deaths involving opioids and non-opioid prescription drugs in the United States

BACKGROUND

Previous studies demonstrate that the reformulation of OxyContin in the U.S. in 2010 induced substitution to illicit opioids, causing illicit opioid markets to grow disproportionately fast in states more exposed to the reformulation. In this paper, we examine if this shift to the illicit market also led to a rise in polysubstance overdose deaths involving non-opioid prescription drugs, including gabapentinoids and "Z-drugs" and, separately, benzodiazepines.

METHODS

Using a difference-in-differences framework, the relationship between exposure to reformulation and overdose death rates including specific substances was studied in each year from 1999 to 2020 while accounting for fixed differences across states, common nationwide shocks, and state-level differences in pain reliever misuse prior to reformulation. Exposure to reformulation was measured as the pre-reformulation rate of OxyContin misuse.

RESULTS

Exposure to reformulation predicted growth in overdose deaths involving gabapentinoids and Z-drugs. There is less evidence that it predicted growth in overdose deaths involving benzodiazepines. However, for all substances, there is strong evidence that pre-reformulation OxyContin misuse rates predicted post-reformulation growth in overdose deaths concurrently involving synthetic opioids.

DISCUSSION

The opioid crisis has changed in radical ways. This study links a major supply-side intervention to the increase in polysubstance overdose deaths involving non-opioid prescription drugs, specifically gabapentinoids and Z-drugs.

Fatalities Involving Substance Use Among US Oil and Gas Extraction Workers Identified Through an Industry Specific Surveillance System (2014-2019)

OBJECTIVE

Characteristics of oil and gas extraction (OGE) work, including long hours, shiftwork, fatigue, physically demanding work, and job insecurity are risk factors for substance use among workers. Limited information exists examining worker fatalities involving substance use among OGE workers.

METHODS

The National Institute for Occupational Safety and Health's Fatalities in Oil and Gas Extraction database was screened for fatalities involving substance use from 2014 through 2019.

RESULTS

Twenty-six worker deaths were identified as involving substance use. Methamphetamine or amphetamine was the most common substances (61.5%) identified. Other contributing factors were lack of seatbelt use (85.7%), working in high temperatures (19.2%), and workers' first day with the company (11.5%).

CONCLUSIONS

Employer recommendations to mitigate substance use-related risks in OGE workers include training, medical screening, drug testing, and workplace supported recovery programs.

Predictors and motives of polydrug use in opioid users. A narrative review

PURPOSE OF REVIEW

To review the recent literature on predictors and personal motives of polydrug use in opioid users with a focus on combined use of opioids with stimulants, benzodiazepines and gabapentinoids.

RECENT FINDINGS

In North America, methamphetamine is now the most prevalent co-drug in opioid users and is responsible for high mortality rates. In Europe, opioids are rather combined with either cocaine, benzodiazepines or gabapentionoids, but recent data are lacking.Main personal motives of opioid users to combine opioids with methamphetamine or cocaine is to boost the opioid high, inhibit the withdrawal effects of heroin and have a cheaper alternative to maintain the opioid high. Risk factors of polydrug use by opioid users included being male, younger age, homelessness, high-risk sexual behavior, needle sharing, incarceration, poor mental health and recent use of cocaine or prescription opioids. The motives for co-use of opioids and gabapentinoids also include seeking a better high, lower price and to self-medicate pain/physical symptoms, including those resulting from withdrawal.

SUMMARY

When treating opioid users with polydrug drug use, special attention should be paid to dosing when in opioid agonist methadone/buprenorphine treatment and to the presence of physical pain. The validity of part of the personal motives seems questionable which deserves attention when counselling opioid users with polydrug use.

Canadian Health Care Professionals' Familiarity with Chronic Cough Guidelines and Experiences with Diagnosis and Management: A Cross-Sectional Survey

INTRODUCTION

Educational programs on chronic cough may improve patient care, but little is known about how Canadian physicians manage this common debilitating condition. We aimed to investigate Canadian physicians' perceptions, attitudes, and knowledge of chronic cough.

METHODS

We administered a 10-min anonymous, online, cross-sectional survey to 3321 Canadian physicians in the Leger Opinion Panel who managed adult patients with chronic cough and had been in practice for > 2 years.

RESULTS

Between July 30 and September 22, 2021, 179 physicians (101 general practitioners [GPs] and 78 specialists [25 allergists, 28 respirologists, and 25 ear/nose/throat specialists]) completed the survey (response rate: 5.4%). In a month, GPs saw a mean of 27 patients with chronic cough, whereas specialists saw 46. About one-third of physicians appropriately identified a duration of > 8 weeks as the definition for chronic cough. Many physicians reported not using international chronic cough management guidelines. Patient referrals and care pathways varied considerably, and patients frequently experienced lost to follow-up. While physicians endorsed nasal and inhaled corticosteroids as common treatments for chronic cough, they rarely used other guideline-recommended treatments. Both GPs and specialists expressed high interest in education on chronic cough.

CONCLUSION

This survey of Canadian physicians demonstrates low uptake of recent advances in chronic cough diagnosis, disease categorization, and pharmacologic management. Canadian physicians also report unfamiliarity with guideline-recommended therapies, including centrally acting neuromodulators for refractory or unexplained chronic cough. This data highlights the need for educational programs and collaborative care models on chronic cough in primary and specialist care.

Gabapentinoids for Pain: A Review of Published Comparative Effectiveness Trials and Data Submitted to the FDA for Approval

Use of the gabapentinoids for pain continues to increase. In 2018, the US Food and Drug Administration (FDA) strengthened the warnings for both gabapentin and pregabalin to emphasize the central nervous system side effects and the risk of respiratory depression, especially when combined with other centrally acting drugs. We reviewed the published comparative effectiveness literature for gabapentinoids for pain as well as all trials (published and unpublished) used by the FDA for the approval of the five pain indications for these agents (one for gabapentin, four for pregabalin). Among the findings of interest are the fact that the FDA rejected the application for gabapentin for diabetic peripheral neuropathy based on the risk versus benefit profile of that drug in the clinical trials that were submitted by the manufacturer. Additionally, both the comparative effectiveness trials as well as the studies used by the FDA tend to be short in duration and show only modest pain benefits for the gabapentinoids. The placebo response in these trials was frequently one-third to one-half as great as the pain benefit demonstrated by the gabapentinoid. Based on the available clinical trial evidence, we feel prescribers should be cautious when using gabapentinoids for pain, particularly when using these agents for a prolonged period or when combined with other, centrally acting agents.

Gabapentin utilization among older adults with different cognitive statuses enrolled in the National Alzheimer's Coordinating Center (2006-2019)

This study aimed to examine gabapentin utilization trends among older adults with different cognitive statuses and investigate concurrent medication use of potentially inappropriate medications. Data were extracted from the National Alzheimer's Coordinating Center Uniform Data Set (2006-2019). We estimated the yearly prevalence of gabapentin use, both overall and within subgroups defined by cognitive status (normal, mild cognitive impairment and dementia) and demographics (age and sex) for participants aged 65+. Additionally, we assessed the prevalence of concurrent use of gabapentin with opioids, combined opioids and benzodiazepine, antidepressant and antipsychotic. From 35 205 eligible older adults (mean age [SD]: 75.7 [7.0]; male: 43.1%), gabapentin use increased from 2006 to 2019 in both overall and every participant subgroup. About 10%-30% of gabapentin users reported to concurrently use opioids, and the concurrent use of gabapentin, opioid and benzodiazepine was up to 7.5% throughout the study period. The frequency of concurrent use with antipsychotics or antidepressants was higher in participants with dementia than those with normal cognition or those who were mildly cognitively impaired. Given increasing use among older adults, rigorous studies are needed to examine the safety of gabapentin in this population.

Understanding motivations and use typologies of gabapentin with opioid agonist medications

BACKGROUND

Prior research suggests a potential relationship between the nonmedical use of gabapentin and use of opioid agonist medications (OAMs), buprenorphine and methadone. However, this research has been limited in scope and understanding despite increases in gabapentin prescribing in opioid use disorder (OUD) treatment settings and increased detection in opioid overdose fatalities.

METHODS

Data were analyzed for 346 participants of a follow-up program to an ongoing national opioid surveillance program of new entrants to treatment for opioid use disorder. Data were sourced from a cross-sectional online survey distributed in July/August 2021.

RESULTS

Lifetime exposure to gabapentin was reported by 60.0 % of the sample, while lifetime history of nonmedical use was reported by 43.2 %. Of those nonmedically using gabapentin, 50.0 % did so while also on a dosage of either buprenorphine or methadone, with 28.4 % engaged in concurrent nonmedical use of both gabapentin and OATs. Motivations for concurrent nonmedical use included high-seeking (38.6 %), self-management of pain/physical symptoms (33.3 %), and self-management of OUD (22.2 %).

CONCLUSIONS

Gabapentin exposure in treatment-seeking persons with OUD appears to be quite common, and use, both medically and nonmedically, frequently occurs alongside OAMs. Motivations for concurrent nonmedical use of gabapentin and OATs mirrors motivations for off-label prescribing by healthcare providers, but may also serve as a form of self-management of OUD when OAM regimens are interrupted, insufficiently prescribed or prescribed at insufficient dosages. Further research should seek to understand the risks versus benefits of gabapentin in OAM treatment settings.