Marijuana Use Is Not Associated With Changes in Opioid Prescriptions or Pain Severity Among People Living With HIV and Chronic Pain

Association of a Positive Drug Screening for Cannabis With Mortality and Hospital Visits Among Veterans Affairs Enrollees Prescribed Opioids

IMPORTANCE

Cannabis has been proposed as a therapeutic with potential opioid-sparing properties in chronic pain, and its use could theoretically be associated with decreased amounts of opioids used and decreased risk of mortality among individuals prescribed opioids.

OBJECTIVE

To examine the risks associated with cannabis use among adults prescribed opioid analgesic medications.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted among individuals aged 18 years and older who had urine drug screening in 2014 to 2019 and received any prescription opioid in the prior 90 days or long-term opioid therapy (LTOT), defined as more than 84 days of the prior 90 days, through the Veterans Affairs health system. Data were analyzed from November 2020 through March 2022.

EXPOSURES

Biologically verified cannabis use from a urine drug screen.

MAIN OUTCOMES AND MEASURES

The main outcomes were 90-day and 180-day all-cause mortality. A composite outcome of all-cause emergency department (ED) visits, all-cause hospitalization, or all-cause mortality was a secondary outcome. Weights based on the propensity score were used to reduce confounding, and hazard ratios [HRs] were estimated using Cox proportional hazards regression models. Analyses were conducted among the overall sample of patients who received any prescription opioid in the prior 90 days and were repeated among those who received LTOT. Analyses were repeated among adults aged 65 years and older.

RESULTS

Among 297 620 adults treated with opioids, 30 514 individuals used cannabis (mean [SE] age, 57.8 [10.5] years; 28 784 [94.3%] men) and 267 106 adults did not (mean [SE] age, 62.3 [12.3] years; P < .001; 247 684 [92.7%] men; P < .001). Among all patients, cannabis use was not associated with increased all-cause mortality at 90 days (HR, 1.07; 95% CI, 0.92-1.22) or 180 days (HR, 1.00; 95% CI, 0.90-1.10) but was associated with an increased hazard of the composite outcome at 90 days (HR, 1.05; 95% CI, 1.01-1.07) and 180 days (HR, 1.04; 95% CI, 1.01-1.06). Among 181 096 adults receiving LTOT, cannabis use was not associated with increased risk of all-cause mortality at 90 or 180 days but was associated with an increased hazard of the composite outcome at 90 days (HR, 1.05; 95% CI, 1.02-1.09) and 180 days (HR, 1.05; 95% CI, 1.02-1.09). Among 77 791 adults aged 65 years and older receiving LTOT, cannabis use was associated with increased 90-day mortality (HR, 1.55; 95% CI, 1.17-2.04).

CONCLUSIONS AND RELEVANCE

This study found that cannabis use among adults receiving opioid analgesic medications was not associated with any change in mortality risk but was associated with a small increased risk of adverse outcomes and that short-term risks were higher among older adults receiving LTOT.

Cannabis-Based Products for Chronic Pain : A Systematic Review

BACKGROUND

Contemporary data are needed about the utility of cannabinoids in chronic pain.

PURPOSE

To evaluate the benefits and harms of cannabinoids for chronic pain.

DATA SOURCES

Ovid MEDLINE, PsycINFO, EMBASE, the Cochrane Library, and Scopus to January 2022.

STUDY SELECTION

English-language, randomized, placebo-controlled trials and cohort studies (≥1 month duration) of cannabinoids for chronic pain.

DATA EXTRACTION

Data abstraction, risk of bias, and strength of evidence assessments were dually reviewed. Cannabinoids were categorized by THC-to-CBD ratio (high, comparable, or low) and source (synthetic, extract or purified, or whole plant).

DATA SYNTHESIS

Eighteen randomized, placebo-controlled trials (n = 1740) and 7 cohort studies (n = 13 095) assessed cannabinoids. Studies were primarily short term (1 to 6 months); 56% enrolled patients with neuropathic pain, with 3% to 89% female patients. Synthetic products with high THC-to-CBD ratios (>98% THC) may be associated with moderate improvement in pain severity and response (≥30% improvement) and an increased risk for sedation and are probably associated with a large increased risk for dizziness. Extracted products with high THC-to-CBD ratios (range, 3:1 to 47:1) may be associated with large increased risk for study withdrawal due to adverse events and dizziness. Sublingual spray with comparable THC-to-CBD ratio (1.1:1) probably is associated with small improvement in pain severity and overall function and may be associated with large increased risk for dizziness and sedation and moderate increased risk for nausea. Evidence for other products and outcomes, including longer-term harms, were not reported or were insufficient.

LIMITATION

Variation in interventions; lack of study details, including unclear availability in the United States; and inadequate evidence for some products.

CONCLUSION

Oral, synthetic cannabis products with high THC-to-CBD ratios and sublingual, extracted cannabis products with comparable THC-to-CBD ratios may be associated with short-term improvements in chronic pain and increased risk for dizziness and sedation. Studies are needed on long-term outcomes and further evaluation of product formulation effects.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality, U.S. Department of Health and Human Services. (PROSPERO: CRD42021229579).

Cannabis use, pain interference, and prescription opioid receipt among persons with HIV: a target trial emulation study

Concomitant with expanded legalization, cannabis is increasingly used to treat chronic pain among persons with HIV (PWH), despite equivocal benefit in research limited by small sample sizes and short duration of follow-up. To address these limitations, among a sample of PWH with pain interference enrolled in the Veterans Aging Cohort Study, we performed a target trial emulation study to compare the impact of four cannabis use strategies on pain interference. Among those receiving long-term opioid therapy (LTOT), we also explored impact of these strategies on ≥ 25% LTOT dose reduction. Among the analytic sample (N = 1284), the majority were men with a mean age of 50. Approximately 31% used cannabis and 12% received LTOT at baseline. Adjusting for demographic and clinical factors, cannabis use in any of 4 longitudinal patterns was not associated with resolved pain interference over 12- to 24-month follow-up. Among 153 participants receiving LTOT at baseline, cannabis use at both baseline and follow-up was negatively associated with LTOT dose reduction compared to no use at both baseline and follow-up. These findings support other observational studies finding no association between cannabis use and improved chronic pain or LTOT reduction among PWH.

Factors Associated with Pain Treatment Satisfaction Among Patients with Chronic Non-Cancer Pain and Substance Use

INTRODUCTION

A better understanding of pain treatment satisfaction in patients with chronic noncancer pain (CNCP) and substance use is needed, especially as opioid prescribing policies are changing. We sought to identify factors associated with pain treatment satisfaction in individuals with CNCP on recent opioid therapy and prior or active substance use.

METHODS

An exploratory cross-sectional analysis using baseline data from a cohort study of 300 adults with CNCP receiving >20 morphine milligram equivalents of opioids for ≥3 of the preceding 12 months and prior or active substance use. Participants completed interviews, clinical assessments, urine drug screening, and medical chart review.

RESULTS

Participants were predominantly middle-aged (mean age 57.5 years), Black (44%), and cisgender men (60%). One-third (33%) had high, 28% moderate, and 39% low pain treatment satisfaction. Post-traumatic stress disorder (PTSD), tobacco use, past-year opioid discontinuation, and higher average pain scores were associated with lower satisfaction. HIV and prescription cannabis use were associated with higher satisfaction.

CONCLUSIONS

The relationship between PTSD and tobacco use with lower satisfaction should be explored to augment pain outcomes. Higher satisfaction among individuals with HIV and prescription cannabis use presents potential research areas to guide CNCP management and reduce reliance on opioid therapies.

Targeting the endocannabinoid system for management of HIV-associated neuropathic pain: A systematic review

Human immunodeficiency virus (HIV) infection and antiretroviral therapy can independently induce HIV-associated neuropathic pain (HIV-NP). There is a dearth of drugs or therapeutic modalities that can alleviate HIV-NP. Smoked cannabis has been reported to improve pain measures in patients with neuropathic pain. Cannabis, phytocannabinoids, and the endocannabinoids such N-arachidonoylethanolamine (anandamide; AEA) and 2-arachidonoylglycerol (2-AG), produce some of their effects via cannabinoid receptors (CBRs). Endocannabinoids are degraded by various enzymes such as fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase. We searched PubMed, Google Scholar, clinicaltrials.gov and clinicaltrialsregister.eu using various key words and their combinations for published papers that studied HIV-NP and cannabis, cannabinoids, or endocannabinoids up to 27th December 2020. All original research articles that evaluated the efficacy of molecules that modulate the endocannabinoid system (ECS) for the prevention and/or treatment of pain in HIV-NP animal models and patients with HIV-NP were included. The PubMed search produced a total of 117 articles, whereas the Google Scholar search produced a total of 9467 articles. Amongst the 13 articles that fulfilled the inclusion criteria 11 articles were found in both searches whereas 2 articles were found in Google Scholar only. The clinicaltrials.gov and clinicaltrialsregister.eu searches produced five registered trials of which three were completed and with results. Ten preclinical studies found that the endocannabinoids (2-AG and AEA), synthetic mixed CB1R/CB2R agonist WIN 55,212-2, a CB2R-selective phytocannabinoid β-caryophyllene, synthetic CB2R-selective agonists (AM1710, JWH015, JWH133 and Gp1a, but not HU308); FAAH inhibitors (palmitoylallylamide, URB597 and PF-3845) and a drug combination of indomethacin plus minocycline, which produces its effects in a CBR-dependent manner, either prevented the development of and/or attenuated established HIV-NP. Two clinical trials demonstrated greater efficacy of smoked cannabis over placebo in alleviating HIV-NP, whereas another clinical trial demonstrated that cannabidivarin, a cannabinoid that does not activate CBRs, did not reduce HIV-NP. The available preclinical results suggest that targeting the ECS for prevention and treatment of HIV-NP is a plausible therapeutic option. Clinical evidence shows that smoked cannabis alleviates HIV-NP. Further research is needed to find out if non-psychoactive drugs that target the ECS and are delivered by other routes than smoking could be useful as treatment options for HIV-NP.

A Mapping Literature Review of Medical Cannabis Clinical Outcomes and Quality of Evidence in Approved Conditions in the USA from 2016 to 2019

In 2017, a National Academies of Sciences, Engineering, and Medicine (NASEM) report comprehensively evaluated the body of evidence regarding cannabis health effects through the year 2016. The objectives of this study are to identify and map the most recently (2016-2019) published literature across approved conditions for medical cannabis and to evaluate the quality of identified recent systematic reviews, published following the NASEM report. Following the literature search from 5 databases and consultation with experts, 11 conditions were identified for evidence compilation and evaluation: amyotrophic lateral sclerosis, autism, cancer, chronic noncancer pain, Crohn's disease, epilepsy, glaucoma, human immunodeficiency virus/AIDS, multiple sclerosis (MS), Parkinson's disease, and posttraumatic stress disorder. A total of 198 studies were included after screening for condition-specific relevance and after imposing the following exclusion criteria: preclinical focus, non-English language, abstracts only, editorials/commentary, case studies/series, and non-U.S. study setting. Data extracted from studies included: study design type, outcome definition, intervention definition, sample size, study setting, and reported effect size. Few completed randomized controlled trials (RCTs) were identified. Studies classified as systematic reviews were graded using the Assessing the Methodological Quality of Systematic Reviews-2 tool to evaluate the quality of evidence. Few high-quality systematic reviews were available for most conditions, with the exceptions of MS (9 of 9 graded moderate/high quality; evidence for 2/9 indicating cannabis improved outcomes; evidence for 7/9 indicating cannabis inconclusive), epilepsy (3 of 4 graded moderate/high quality; 3 indicating cannabis improved outcomes; 1 indicating cannabis inconclusive), and chronic noncancer pain (12 of 13 graded moderate/high quality; evidence for 7/13 indicating cannabis improved outcomes; evidence from 6/7 indicating cannabis inconclusive). Among RCTs, we identified few studies of substantial rigor and quality to contribute to the evidence base. However, there are some conditions for which significant evidence suggests that select dosage forms and routes of administration likely have favorable risk-benefit ratios (i.e., epilepsy and chronic noncancer pain). The body of evidence for medical cannabis requires more rigorous evaluation before consideration as a treatment option for many conditions, and evidence necessary to inform policy and treatment guidelines is currently insufficient for many conditions.

Practical Strategies Using Medical Cannabis to Reduce Harms Associated With Long Term Opioid Use in Chronic Pain

Background: Chronic non-cancer pain (CNCP) is estimated to affect 20% of the adult population. Current United States and Canadian Chronic non-cancer pain guidelines recommend careful reassessment of the risk-benefit ratio for doses greater than 90 mg morphine equivalent dose (MED), due to low evidence for improved pain efficacy at higher morphine equivalent dose and a significant increase in morbidity and mortality. There are a number of human studies demonstrating cannabis opioid synergy. This preliminary evidence suggests a potential role of cannabis as an adjunctive therapy with or without opioids to optimize pain control.

Methods: In 2017, the Canadian Opioid Guidelines Clinical Tool was created to encourage judicious opioid prescribing for CNCP patients and to reevaluate those who have been chronically using high MED. Mirroring this approach, we draw on our clinical experiences and available evidence to create a clinical tool to serve as a foundational clinical guideline for the initiation of medical cannabis in the management of CNCP patients using chronic opioid therapy.

Findings: Following principles of harm reduction and risk minimization, we suggest cannabis be introduced in appropriately selected CNCP patients, using a stepwise approach, with the intent of pain management optimization. We use a structured approach to focus on low dose cannabis (namely, THC) initiation, slow titration, dose optimization and frequent monitoring.

Conclusion: When low dose THC is introduced as an adjunctive therapy, we observe better pain control clinically with lower doses of opioids, improved pain related outcomes and reduced opioid related harm.

Opioid-sparing effects of cannabinoids: Myth or reality?

A converging line of evidence is indicating that cannabinoids may have an opioid-sparing effect. This property, well validated in preclinical studies, allow when both drugs are co-administered to reduce the dose of opioids without loss of analgesic effects. A meta-analysis of pre-clinical studies indicated in 2017 that the median effective dose (ED₅₀) of morphine administered in combination with delta-9-tetrahydrocannabinol (delta-9-THC) is 3.6 times lower than the ED₅₀ of morphine alone (Nielsen et al., 2017). However, very few studies have been conducted in humans to validate this effect. This narrative review provides an update on whether or not cannabinoid drugs can be used to produce an opioid sparing effect. For this, various lines of evidence ranging from preclinical, epidemiological and human studies will be summarized. Overall, this review indicates that the preclinical results are strongly and consistently supportive of the presence of an opioid sparing effect of cannabinoid drugs. However, to date the clinical studies have been mostly negative; and, the evidence collected in humans so far is so limited that it is premature to conclude. Therefore, prospective high quality controlled clinical trials are still required to validate this. Priorities for future research are also discussed.

Demand curve analysis of marijuana use among persons living with HIV

BACKGROUND

Despite medicalization and legalization of marijuana use, factors influencing demand for marijuana among persons living with HIV (PLWH) are incompletely understood. This knowledge gap undermines effective clinical management and policies. This study used demand curve simulation methods to address these issues.

METHODS

Marijuana-using PLWH (N = 119) completed experimental tasks to simulate amount of marijuana purchasing/use across different costs (money or time), and likelihood of reselling marijuana or marijuana therapeutic-use registration card in relation to profits. Additional simulations assessed purchasing of marijuana relative to other drug and non-drug goods.

RESULTS

Simulated marijuana use decreased as money and time costs increased. Consumption was greater for participants with more severe Cannabis Use Disorder (CUD) and anxiety, intermediate pain levels, and past 90-day opioid use. Whereas few participants chose to sell their registration card, marijuana resale (diversion) steeply increased with profit. Likelihood of seeking marijuana therapeutic-use certification decreased in relation to registration card money cost, having to visit more physicians to get a signature, and delay to receiving the card, and increased with duration of certification. Participants who reported recent opioid use were more likely to seek certification. Consumption of several commodities assessed was independent of marijuana.

CONCLUSIONS

Simulated marijuana use was related to participants' clinical profile (CUD, anxiety and pain symptoms, recent opioid use), and unrelated to purchasing other goods. Likelihood of seeking marijuana therapeutic-use registration was affected by several types of costs and recent opioid use. Participants were unlikely to divert registration cards. We discuss clinical and policy implications of these findings.

Variations in Long-term Opioid Therapy Definitions: A Systematic Review of Observational Studies Using Routinely Collected Data (2000-2019)

Routinely collected data have been increasingly used to assess long-term opioid therapy (LTOT) patterns, with very little guidance on how to measure LTOT from these data sources. We conducted a systematic review of studies published between January 2000 and July 2019 to catalogue LTOT definitions, the rationale for definitions and LTOT rates in observational research using routinely collected data in nonsurgical settings. We screened 4056 abstracts, 210 full-text manuscripts and included 128 studies, mostly from the United States (81%) and published between 2015 and 2019 (69%). We identified 78 definitions of LTOT, commonly operationalised as 90 days of use within a year (23%). Studies often used multiple criteria to derive definitions (60%), mostly based on measures of duration, such as supply days/days of use (66%), episode length (21%) or prescription fills within specified time periods (12%). Definitions were based on previous publications (63%), clinical judgment (16%) or empirical data (3%); 10% of studies applied more than one definition. LTOT definition was not provided with enough details for replication in 14 studies and 38 studies did not specify the opioids evaluated. Rates of LTOT within study populations ranged from 0.2% to 57% according to study design and definition used. We observed a substantial rise in the last 5 years in studies evaluating LTOT with large variability in the definitions used and poor reporting of the rationale and implementation of definitions. This variation impacts on research reproducibility, comparability of findings and the development of strategies aiming to curb therapy that is not guideline-recommended.

Cannabis Use and Nonfatal Opioid Overdose among Patients Enrolled in Methadone Maintenance Treatment

BACKGROUND

Some ecological studies found lower rates of opioid overdose in states with liberalized cannabis legislation, but results are mixed, and the association has not been analyzed in individuals. We quantified the association between cannabis use and nonfatal opioid overdose among individuals enrolled in methadone maintenance treatment (MMT) for opioid use disorder (OUD).

METHODS

We recruited a convenience sample of individuals enrolled in four MMT clinics in Washington State and southern New England who completed a one-time survey.Descriptive statistics and multivariate logistic regression compared the prevalence and risk of nonfatal opioid overdose in the past 12 months between participants reporting frequent (at least weekly) or infrequent (once or none) cannabis use in the past month.

RESULTS

Of 446 participants, 35% (n = 156) reported frequent cannabis use and 7% (n = 32) reported nonfatal opioid overdose in the past year. The prevalence of nonfatal opioid overdose was 3% among reporters of frequent cannabis use, and 9% among reporters of infrequent/no use (p = 0.02). After imputing missing data and controlling for demographic and clinical factors, the likelihood of self-reported nonfatal opioid overdose in the past year was 71% lower among reporters of frequent cannabis use in the past month (adjusted RR = 0.29, 95% CI 0.10-0.80, p = 0.02).

CONCLUSIONS

Among individuals enrolled in MMT, frequent cannabis use in the past month was associated with fewer self-reported nonfatal opioid overdoses in the past year. Methodological limitations caution against causal interpretation of this relationship. Additional studies are needed to understand the prospective impact of co-occurring cannabis on opioid-related outcomes.

Factors associated with current and severe pain among people living with HIV: results from a statewide sample

Background

People living with HIV (PLHIV) are more likely to suffer from pain compared to the general public. Pain often clusters with mental health symptoms and substance use. This study sought to evaluate mental health and substance use factors associated with any pain and severe pain intensities among PLHIV.

Methods

Data were derived from HIV+ adults (N = 733) recruited from community health centers across Florida who completed questionnaires regarding demographics, chronic pain, HIV clinical outcomes, mental health symptoms, and substance use information. Pain was assessed using the Brief Pain Inventory (BPI) short form. Multivariate logistic regression analysis was utilized to assess the relationship between selected covariates and pain.

Results

Approximately half (45.0%) of participants reported having any current pain while 16.1% reported severe pain. The odds of having any current pain were 2.49 (CI 95% 1.48, 4.18, p <  0.01) times greater among PLHIV reporting anxiety and 1.69 (CI 95% 1.11, 2.57, p = 0.01) times greater among PLHIV reporting PTSD compared to those without those factors. The odds of having severe pain were 2.03 (CI 95% 1.03, 4.01, p = 0.04) times greater among PLHIV reporting anxiety and 2.02 (CI 95% 1.26, 3.24, p <  0.01) times greater among female participants compared to PLHIV without those factors respectively. Factors including depression, alcohol consumption, and marijuana use were not statistically associated with any current pain nor with severe pain.

Conclusion

The relationship between pain and mental health is complex. Thus, future research is needed to determine if pain treatments may reduce mental health symptoms or if treatments can be targeted to address both issues simultaneously.

Marijuana Use and Its Associations With Pain, Opioid Dose, and HIV Viral Suppression Among Persons Living With HIV on Chronic Opioid Therapy

BACKGROUND

Medical marijuana is legal in 29 US states and the District of Columbia: both HIV and chronic pain are "approved conditions" for receipt. Chronic pain is common among people living with HIV (PLWH). We anticipate PLWH will question their providers about medical marijuana for chronic pain. We examined marijuana use and its associations with pain, opioid dose, and HIV viral suppression among PLWH receiving chronic opioid therapy.

METHODS

PLWH prescribed chronic opioid therapy were recruited into the Targeting Effective Analgesia in Clinics for HIV cohort. The main exposure variable was any past 12-month marijuana use. The primary outcomes were (1) opioid misuse (≥9 on the Current Opioid Misuse Measure) and (2) opioid dose (morphine equivalent daily dose). HIV viral load (VL) suppression (<200 copies/μL) and pain severity and interference using the Brief Pain Inventory were exploratory outcomes.

RESULTS

Participants (n = 166) were men (65%), Black (72%), and had an undetectable VL (89%). We found no significant association between current marijuana use and opioid misuse, opioid dose, or pain. Current marijuana use was associated with 3.03 times the odds of having a detectable VL (95% odds ratio: 1.11-8.31, P = 0.03) while controlling for depressive symptoms and other substance use.

DISCUSSION

We did not detect an association between marijuana use and opioid misuse behaviors, opioid dose, or pain. In an exploratory analysis, current marijuana use was associated with 3× greater odds of having a detectable VL. This study provides insights into potential consequences of marijuana use among PLWH with chronic pain.

Adverse Consequences of Co-Occurring Opioid Use Disorder and Cannabis Use Disorder Compared to Opioid Use Disorder Only

Background: While there is growing interest in the possibility that cannabis may be a partial substitute for opioids, studies have yet to examine whether individuals with co-occurring opioid and cannabis use disorders (OUD and CUD) have less risk of negative outcomes than those with OUD only. Objective: This study sought to compare the sociodemographic and clinical characteristics of patients diagnosed with co-occurring OUD and CUD to patients with OUD only, CUD only, and patients with any other drug use disorders. We hypothesized that co-occurring OUD and CUD would be associated with lower risk of inpatient admissions and emergency department (ED) visits, lower rates of homelessness, and fewer opioid prescriptions. Methods: Comparisons were based on bivariate analyses, logistic and linear multiple regression models of National Veterans Health Administration (VHA) data from Fiscal Year 2012. Results: Of the 234,181 (94% male) patients diagnosed with drug use disorders, 8.6% were diagnosed with co-occurring OUD and CUD; 33.3% with OUD only; 26.5% with CUD only; and 31.6% with other drug use disorders. Compared to the OUD only group (Mean = 4.8 (SD = 8.84)), the group with co-occurring OUD and CUD was associated with a lower number of opioid prescriptions (Mean = 3.79 (SD = 8.22)) (d = -0.16), but higher likelihood of inpatient psychiatric admission (RR = 1.95) and homelessness (RR = 1.52), and no significant difference in ED visits. Conclusions: These data highlight the need to further investigate whether the complex effects of cannabis use on patients with OUD are counterbalanced by potential benefits of reduced in opioid prescribing.