Marijuana users are likely to report opioid misuse among adults over 50 years in representative sample of the United States (2002-2014)

The relationship between medical marijuana use and prescription pain reliever use among U.S. adults: A retrospective analysis utilizing the 2015-2019 National Survey on Drug Use and Health (NSDUH)

Background

Despite a number of states in the U.S. enacting medical marijuana policies, there is currently a lack of research outlining the role that individual-level factors play in predicting medical marijuana use, especially regarding use and misuse of prescription pain relievers. The overall aim of this study was to assess the prevalence of medical marijuana use in the U.S. and to identify clinical, social, and demographic predictors.

Methods

A retrospective secondary database analysis was conducted utilizing five years of the National Survey on Drug Use and Health (NSUDH). A multivariable logistic regression model assessed the association between prescription pain reliever use and medical marijuana in the adult U.S. population while adjusting for substance use factors, psychiatric factors, and demographic characteristics.

Results

Within the U.S. adult population from 2015 to 2019, medical marijuana use increased from 1.6% to 2.4%, while appropriate prescription pain reliever use decreased from 33.4% to 27.5%, and prescription pain reliever misuse decreased from 4.7% to 3.7%. Of all marijuana users, 15.1% resided within non-medical marijuana states. Medical marijuana users are more likely to have a serious mental illness (14.0% vs. 4.4%) and a non-marijuana related substance dependence (5.3% vs. 1.2%). Past-year medical marijuana use was significantly more likely to be reported among appropriate users of prescription pain relievers (OR = 1.99, p < .001) and misusers (OR = 1.94, p < .001) (relative to nonusers).

Conclusions

Prescription pain reliever appropriate use and misuse were associated with higher odds of medical marijuana use. This study identified a potential treatment gap among individuals residing in states with no medical marijuana availability. These study findings highlight the potential benefits of medical marijuana legalization that future research can build on to guide policy making decisions.

Impacts of medical and non-medical cannabis on the health of older adults: Findings from a scoping review of the literature

BACKGROUND

Cannabis legalization has enabled increased consumption in older adults. Age-related mental, physical, and physiological changes may lead to differences in effects of cannabis in older adults compared to younger individuals.

OBJECTIVE

To perform a scoping review to map the evidence regarding the health effects of cannabis use for medical and non-medical purposes in older adults.

METHODS

Electronic databases (MEDLINE, Embase, PsycINFO, Cochrane Library) were searched for systematic reviews (SRs), randomized controlled trials (RCTs) and non-randomized/observational studies (NRSs) assessing the health effects and associations of cannabis use (medical or non-medical) in adults ≥ 50 years of age. Included studies met age-related inclusion criteria or involved a priori identified health conditions common among older adults. Records were screened using a liberal accelerated approach and data charting was performed independently by two reviewers. Descriptive summaries, structured tables, effect direction plots and bubble plots were used to synthesize study findings.

FINDINGS

From 31,393 citations, 133 publications describing 134 unique studies (26 SRs, 36 RCTs, 72 NRSs) were included. Medical cannabis had inconsistent therapeutic effects in specific patient conditions (e.g., end-stage cancer, dementia), with a number of studies suggesting possible benefits while others found no benefit. For medical cannabis, harmful associations outnumbered beneficial, and RCTs reported more negative effects than NRSs. Cannabis use was associated with greater frequencies of depression, anxiety, cognitive impairment, substance use and problematic substance use, accidents/injuries, and acute healthcare use. Studies often were small, did not consistently assess harms, and did not adjust for confounding.

DISCUSSION

The effects of medical cannabis are inconsistent within specific patient conditions. For older adults, generally, the available evidence suggests cannabis use may be associated with greater frequencies of mental health issues, substance use, and acute healthcare use, and the benefit-to-risk ratio is unclear. Studies with a balanced assessment of benefits and harms may guide appropriate public health messaging to balance the marketing pressures of cannabis to older adults.

Ageing and older people who use illicit opioids, cocaine or methamphetamine: a scoping review and literature map

AIMS

To provide an overview of research literature on ageing and older people who use illicit opioids and stimulants by documenting the conceptual frameworks used and content areas that have been investigated.

METHODS

We conducted a scoping review of literature relating to ageing and older people who use illicit stimulants and opioids, defining 'older' as 40 years and above. Primary studies, secondary studies and editorials were included. Searches were conducted in PubMed and Embase in July 2020 and March 2021; the Cochrane library was searched in November 2021. Charted data included methodological details, any conceptual frameworks explicitly applied by authors and the content areas that were the focus of the publication. We developed a hierarchy of content areas and mapped this to provide a visual guide to the research area.

RESULTS

Of the 164 publications included in this review, only 16 explicitly applied a conceptual framework. Seven core content areas were identified, with most publications contributing to multiple content areas: acknowledgement of drug use among older people (n = 64), health status (n = 129), health services (n = 109), drug use practices and patterns (n = 84), social environments (n = 74), the criminal legal system (n = 28) and quality of life (n = 15).

CONCLUSIONS

The literature regarding older people who use illicit drugs remains under-theorized. Conceptual frameworks are rarely applied and few have been purposely adapted to this population. Health status and health services access and use are among the most frequently researched topics in this area.

Associations of Healthcare Service Utilization With Cannabis Use Status, Use Reasons, and Use Characteristics Among Those Age 50 and Older

Cannabis use has increased steadily among older adults, and they are a significant proportion of medical cannabis users. Using 2015-2019 National Survey on Drug Use and Health data (n = 44,007 age 50+), we examined whether the numbers of emergency department (ED) visits and nights hospitalized are associated with cannabis use status, use reason (nonmedical-only, medical-only, and medical and nonmedical), and use characteristics. Past-year users had higher rates of any ED visit (30.0%) and hospitalization (14.7%) than prior-to-past-year users and never users. However, negative binomial regression models showed that past-year users did not differ from never users on numbers of ED visits and nights hospitalized, although they had more ED visits than prior-to-past-year users (IRR = 1.21, 95% CI = 1.10-1.34). Medical-only users had more ED visits (IRR = 1.38, 95% CI = 1.02-1.88) than nonmedical-only users. Cannabis use and use characteristics were not associated with nights hospitalized. The study findings provide insights into older cannabis users' healthcare utilization.

Effects of combined THC and heroin vapor inhalation in rats

RATIONALE

Opioids are effective medications, but they have several key limitations including the development of tolerance, establishment of dependence, diversion for non-medical use, and the development of addiction. Therefore, any drugs which act in an additive or synergistic fashion with opioids to address medical applications have the potential to reduce opioid-related harms.

OBJECTIVES

To determine if heroin and Δ⁹-tetrahydrocannabinol (THC) interact in an additive or independent manner to alter nociception, body temperature, and spontaneous locomotor activity when inhaled or injected.

METHODS

Groups of female and male rats, implanted with radiotelemetry transmitters, were exposed to vapor generated from heroin (50 mg/mL in propylene glycol vehicle; PG), THC (50 mg/mL), or the combination for assessment of effects on temperature and activity. Thermal nociception was assessed with a warm water tail-withdrawal assay.

RESULTS

Heroin inhalation increased temperature and activity whereas THC inhalation decreased temperature and activity in both female and male Sprague-Dawley rats. Effects of combined inhalation were in opposition, and additional experiments found the same outcome for the injection of heroin (0.5 mg/kg, s.c.) and THC (10 mg/kg, i.p.) alone and in combination. In contrast, the co-administration of heroin and THC by either inhalation or injection produced additive effects on thermal nociception in both male and female Sprague-Dawley and Wistar rats.

CONCLUSIONS

This study shows that additive effects of THC with an opioid on a medical endpoint such as analgesia may not generalize to other behavioral or physiological effects, which may be a positive outcome for unwanted side effects.