The motives and methods of methamphetamine and 'heroin' co-use in West Virginia

Prevalence of adults with stimulant misuse and/or stimulant use disorder in Massachusetts, USA, 2014-2021

BACKGROUND AND AIMS

Stimulant-involved overdose deaths are increasing throughout the United States. Because stimulant misuse (i.e. taking a prescribed medicine not as directed) and stimulant use disorder contribute to the surging number of stimulant-related deaths, knowing the prevalence of stimulant misuse and use disorder is important. We aimed to estimate the prevalence of stimulant misuse and/or use disorder in Massachusetts from 2014 to 2021.

DESIGN, SETTING AND PARTICIPANTS

This was a cohort study using a multiple systems estimation approach (previously known as 'capture-recapture'), using multiple individually linked epidemiological data sources, located in the Commonwealth of Massachusetts, 2014-2021. People aged 18-64 years from administrative databases were linked at the individual level and included in the analysis.

MEASUREMENTS

Measurements included known and estimated counts of people with stimulant misuse and/or use disorder (as defined in each individual database) as well as total count and prevalence in Massachusetts. We performed both a stratified analysis using log-linear models to estimate the unknown population with stimulant misuse/use disorder and a single model analysis in which demographics were used as covariates. Uncertainty is characterized using 95% confidence intervals (95% CI) on the total counts and prevalence estimates.

FINDINGS

The number of known individuals increased during the study period from 31 037 in 2014 to 42 612 in 2021. Using the multiple systems estimation approach, the estimated prevalence of underlying stimulant misuse and/or use disorder population ranged from 4.1 to 7.1% during the study period in the stratified analysis and 4.2 to 6.8% in the single model. By race, the highest prevalence estimates were among the Black non-Hispanic population, which showed a prevalence of up to 14.5% (95% CI = 14.32%, 14.57%) in 2021.

CONCLUSIONS

The estimated prevalence of stimulant misuse and/or use disorder in Massachusetts from 2014 to 2021 ranged from 4% to nearly 7% of the population. People from racial minorities appear to be disproportionately affected compared with the white non-Hispanic population. The unknown population accounted for large proportions of the total estimated population.

Prevalence and Correlates of Alcohol and Drug Harms to Others: Findings From the 2020 U.S. National Alcohol Survey

OBJECTIVE

The purpose of this study was to measure the prevalence and overlap of secondhand harms from other people's use of alcohol, cannabis, opioids, or other drugs and examine sociodemographic and other correlates of these secondhand harms.

METHOD

This cross-sectional analysis used data from 7,799 respondents (51.6% female; 12.9% Black, 15.6% Hispanic/Latiné; mean age = 47.6 years) in the 2020 U.S. National Alcohol Survey. Secondhand harms included family/marriage difficulties, traffic accidents, vandalism, physical harm, and financial difficulties. Weighted prevalence estimates provided nationally representative estimates of these harms. Logistic regression assessed associations between individual characteristics and secondhand harms.

RESULTS

Lifetime prevalence of secondhand harms from alcohol, cannabis, opioids, or other drugs was 34.2%, 5.5%, 7.6%, and 8.3%, respectively. There was substantial overlap among lifetime harms: Almost 30% of those reporting secondhand alcohol harms also reported secondhand drug harms. Significant correlates of secondhand substance harms included female sex (alcohol, other drugs); White (alcohol, opioids), American Indian/Alaska Native (opioids), and Black (cannabis) race/ethnicity; and separated/divorced/widowed marital status (opioids). Those reporting a family history of alcohol problems had significantly higher odds of reporting secondhand harms across substance types. Individuals who reported frequent cannabis use had higher odds of reporting secondhand alcohol and opioid harms compared to those with no cannabis use (aOR = 1.55; aOR = 2.38) but lower odds of reporting secondhand cannabis harms (aOR = 0.51).

CONCLUSIONS

Although less prevalent than secondhand alcohol harms, 14% of participants reported secondhand harms from someone else's drug use and frequently experienced secondhand harms attributed to multiple substances. Population-focused interventions are needed to reduce the total burden of alcohol and other drug use.

Levels of engagement among office-based opioid treatment (OBOT) patients with concurrent methamphetamine use

BACKGROUND AND OBJECTIVES

Recent increases in methamphetamine use among people seeking treatment for opioid use disorder (OUD) has created significant demand for effective approaches to support this clinical population. This study assessed the extent to which office-based opioid treatment (OBOT) patients, who were diagnosed with methamphetamine use disorder (MUD), engaged with providers.

METHODS

A retrospective analysis was conducted of adult patients (n = 470) seeking treatment for OUD who attended at least one visit between March 2020 and March 2023 at a rural regional OBOT provider. Approximately one quarter (28.7%) of patients were diagnosed with MUD in addition to receiving an OUD diagnosis. Bivariate methods and multivariate negative binomial regression models were estimated to examine the associations between clinical measures and the numbers of office visits, peer visits, and telehealth visits.

RESULTS

Regression results indicated patients who met criteria for MUD in addition to OUD attended a higher rate of peer visits (incidence rate ratio [IRR] = 2.63, p = .036) when compared to patients who did not meet criteria for MUD. In contrast, patients with MUD and OUD diagnoses displayed significantly lower (IRR = 0.68, p < .001) engagement rates through fewer office visits relative to those who did not meet MUD criteria.

DISCUSSION AND CONCLUSIONS

Patients seeking treatment for OUD who meet criteria for MUD are more likely to engage through peer support specialists rather than office visits.

SCIENTIFIC SIGNIFICANCE

This study demonstrates the ways patients who meet criteria for OUD and MUD engage with providers to receive treatment.

U.S. trends in methamphetamine-involved psychiatric hospitalizations in the United States, 2015-2019

BACKGROUND

In the U.S., overdose deaths and substance treatment admissions related to methamphetamine are rising. This study aims to measure and compare U.S. temporal trends in methamphetamine-involved psychiatric hospitalizations.

METHODS

We conducted a population-based, trend analysis of U.S. psychiatric hospitalizations and calculated quarterly (Q) rates per 100,000 population of substance-involved psychiatric hospitalizations. We assessed U.S. regional quarterly percentage hospitalization rate changes using Joinpoint regression.

RESULTS

From Q4 2015-Q4 2019, there were 963,202 psychiatric hospitalizations, 50,223 (5.2 %) involved methamphetamine and 102,877 (10.7 %) involved opioids and/or cocaine without methamphetamine. Methamphetamine-involved psychiatric hospitalization rates increased by 68.0 %, psychiatric hospitalizations rates involving opioid and/or cocaine without methamphetamine decreased by 22 %, while nonsubstance-involved psychiatric hospitalizations rates remained unchanged. The largest significant increases in methamphetamine-involved psychiatric hospitalization rates were among people >61 years old, males, and Midwesterners. Methamphetamine-involved psychiatric hospitalization rates doubled among Black patients. The largest average percent increase among methamphetamine-involved psychiatric hospitalizations was 10.2 % from Q4 2015-Q2 2017 in the Midwest.

CONCLUSION AND RELEVANCE

Most psychiatric hospitalizations did not involve substances. Methamphetamine-involved psychiatric hospitalizations greatly increased while opioid-involved psychiatric hospitalizations decreased, but involved more total encounters. Greater access to harm reduction services, contingency management programs, and mental health services is urgently needed.

Co-administration of naloxone and dexmedetomidine to simultaneously reverse acute effects of fentanyl and methamphetamine in rats

BACKGROUND

The incidence of combination methamphetamine (METH)-opioid overdose has substantially increased in recent years. While agitation is uncommon after the naloxone (NLX) reversal of opioids, it is a major clinical concern in acute METH intoxication and can be physiologically antagonized by opioid-induced sedation. This study aimed to perform initial preclinical analysis of the safety and efficacy of dexmedetomidine (DEXMED) co-administered with NLX to attenuate METH-induced locomotor activity, as a rat model of agitation, after the reversal of fentanyl (FENT)-induced sedation.

METHODS

Male Sprague Dawley rats were administered subcutaneous (SC) 0.1mg/kg FENT ± 1mg/kg METH. Fifteen min later, SC 0.1mg/kg NLX ± an increasing (0, 0.032, 0.056, and 0.1mg/kg) DEXMED dose was administered prior to the measurement of locomotor activity. After a washout period, the FENT ± METH and NLX ± DEXMED administration with the highest dose of DEXMED was administered for measurement of blood oxygen saturation and heart rate.

RESULTS

After the NLX reversal of FENT-induced sedation, adjunct DEXMED substantially and significantly reduced METH-induced locomotor activity (p<0.05) at all doses tested. While the addition of DEXMED did not significantly reduce blood oxygenation in METH treated rats, it did so in the absence of METH. Also, DEXMED significantly reduced heart rate compared to non-DEXMED treated groups and resulted in further significant reductions in the animals not exposed to METH (p<0.05).

CONCLUSIONS

These data provide preclinical evidence that DEXMED may be a safe and effective chemical restraint for METH-induced agitation after NLX opioid reversal.

Estimating changes in overdose death rates from increasing methamphetamine supply in Ohio: Evidence from crime lab data

Background

We investigate the relationship between the supply of methamphetamine and overdose death risk in Ohio. Ohio and the overall US have experienced a marked increase in overdose deaths from methamphetamine combined with fentanyl over the last decade. The increasing use of methamphetamine may be increasing the risk of overdose death. However, if people are using it to substitute away from more dangerous synthetic opioids, it may reduce the overall risk of overdose death.

Methods

Ohio's Bureau of Criminal Investigation's crime lab data include a detailed list of the content of drug samples from law enforcement seizures, which are used as a proxy for drug supply. We use linear regressions to estimate the relationship between the proportion of methamphetamine in lab samples and unintentional drug overdose death rates from January 2015 through September 2021.

Results

Relatively more methamphetamine in crime lab data in a county-month has either no statistically significant relationship with overdose death rates (in small and medium population counties) or a negative and statistically significant relationship with overdose death rates (in large population counties). Past overdose death rates do not predict future increases in methamphetamine in crime lab data.

Conclusions

The results are consistent with a relatively higher supply of methamphetamine reducing the general risk of overdose death, possibly due to substitution away from more dangerous synthetic opioids. However, the supply of methamphetamine appears unrelated to the past illicit drug risk environment. The non-lethal and yet serious health effects of MA use were not explored and, thus, even if the presence of MA reduces the population-level overdose mortality rate, the rise of other adverse health effects may counteract any public health benefits of fewer deaths.

Changes in injecting versus smoking heroin, fentanyl, and methamphetamine among people who inject drugs in San Diego, California, 2020-2023

BACKGROUND

Amidst an increasingly toxic drug supply in North America, people who inject drugs may be transitioning to smoking them. We aimed to assess changes in injecting and smoking opioids and methamphetamine among a cohort of people who inject drugs from San Diego, California.

METHODS

Over five six-month periods spanning October 2020-April 2023, we assessed prevalence of injecting and smoking opioids or methamphetamine and whether participants used these drugs more frequently by smoking than injecting. Multivariable Poisson regression via generalized estimating equations was used to examine time trends.

RESULTS

Of 362 participants, median age was 40 years; a minority were female (29%), Hispanic/Latinx/Mexican (45%), and housed (33%). Among this cohort, of whom 100% injected (and 84% injected and smoked) in period one (October 2020-April 2021), by period five (November 2022-April 2023), 34% only smoked, 59% injected and smoked, and 7% only injected. By period five, the adjusted relative risk (aRR) of injecting opioids was 0.41 (95% Confidence Interval [CI]: 0.33, 0.51) and the aRR for injecting methamphetamine was 0.50 (95% CI: 0.39, 0.63) compared to period one. Risks for smoking fentanyl rose significantly during period three (aRR=1.44, 95% CI: 1.06, 1.94), four (aRR=1.65, 95% CI: 1.24, 2.20) and five (aRR=1.90, 95% CI: 1.43, 2.53) compared to period one. Risks for smoking heroin and methamphetamine more frequently than injecting these drugs increased across all periods.

CONCLUSIONS

Opioid and methamphetamine injection declined precipitously, with notable increases in smoking these drugs. Research is needed to understand the health consequences of these trends.

Strategies to Improve Patient-Centered Care for Drug Use-Associated Infective Endocarditis: JACC Focus Seminar 2/4

Drug use-associated infective endocarditis (DUA-IE) is a major cause of illness and death for people with substance use disorder (SUD). Investigations to date have largely focused on advancing the care of patients with DUA-IE and included drug use disorder treatment, decisions about surgery, and choice of antibiotics during the period of hospitalization. Transitions from hospital to outpatient care are relatively unstudied and frequently a key factor of uncontrolled infection, continued substance use, and death. In this paper, we review the evidence supporting cross-disciplinary care for people with DUA-IE and highlight domains that need further clinician, institutional, and research investment in clinicians and institutions. We highlight best practices for treating people with DUA-IE, with a focus on addressing health disparities, meeting health-related social needs, and policy changes that can support care for people with DUA-IE in the hospital and when transitioning to the community.

Patterns and Characteristics of Amphetamine-type Stimulant Use in a North-eastern State of India: A Cross-sectional Study

Background

South Asia generally reports low levels of amphetamine-type stimulant (ATS) use, with few studies on the pattern of ATS use. We assessed the pattern of ATS use and associated high-risk behavior in Manipur, a north-eastern state of India.

Methods

209 adult male ATS users (mean age 28.8 years) from three districts of Manipur were interviewed. Data were collected on the patterns of high-risk behavior with ATS use, health consequences, and help-seeking. The severity of use with various substances was assessed using the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST). Depression and anxiety were assessed by the Patient Health Questionnaire (PHQ-9) and Generalized Anxiety Disorder (GAD-7) scale, respectively.

Results

The mean duration of ATS use was 3.7 years (SD 2.3). The majority used ATS almost daily (88%) and depended on ATS (77%). Methamphetamine (99.5%) was the most used ATS orally. Around 87% also suffered from opioid dependence. About 76% injected drugs, most commonly heroin. Almost three-fourths (78%) used ATS before their sexual intercourse, 31% of whom did not use condoms. Most reported physical problems with ATS and had above-cut-off scores on PHQ-9 and GAD-7. The majority (95%) reported that they could procure ATS easily. Also, the majority (93%) had thought of quitting ATS use.

Discussion

Most ATS users start using ATS at a young age and have comorbid other drug use, including heroin. ATS use is associated with various physical and psychological problems. Focusing on ATS use in India and developing strategies to address this problem is essential.

Longitudinal patterns of use of stimulants and opioids in the AIDS linked to the IntraVenous experience cohort, 2005-2019

BACKGROUND

Overdoses involving opioids and stimulants are on the rise, yet few studies have examined longitudinal trends in use of both substances. We sought to describe use and co-use of opioids and stimulants, 2005-2019, in the AIDS Linked to the Intravenous Experience (ALIVE) cohort - a community-based cohort of people with a history of injection drug use living in or near Baltimore, MD.

METHODS

We included 2083 ALIVE participants, who had at least two visits during the study period. Our outcome was based on self-reported use of opioids and stimulants in the prior 6 months. We estimated prevalence of 4 categories of use (neither stimulants nor opioids, only stimulants, only opioids, stimulants and opioids), using a non-parametric multi-state model, accounting for the competing event of death and weighting for informative loss to follow-up. All analyses were stratified by enrollment cohort, with the main analysis including participants who enrolled prior to 2015 and a sub-analysis including participants who enrolled 2015-2018.

RESULTS

In the main analysis, prevalence of using stimulants and opioids decreased from 38 % in 2005 to 12 % 2013 but stabilized from 2014 onwards (13-19 %). The prevalence of using only stimulants (7-11 %) and only opioids (5-10 %) was stable across time. Participants who reported using both were more likely to report homelessness, depression, and other substance use (e.g., marijuana and heavy alcohol use) than participants in the other use categories. On average, 65 % of visits with use of both were followed by a subsequent visit with use of both; of participants transitioning out of using both, 13% transitioned to using neither.

CONCLUSIONS

While use of stimulants and opioids declined in the cohort through 2013, a meaningful proportion of participants persistently used both. More research is needed to understand and develop strategies to mitigate harms associated with persistent use of both stimulants and opioids.

Patterns of polydrug use among Black Americans who misuse opioids

In the United States, opioid-related deaths involving polydrug use are now more prevalent than those involving only opioids. What often goes unnoticed is that deaths involving more than one substance are increasing more rapidly among Black Americans than Whites. Unfortunately, little research attention is paid to understanding opioid-related polydrug use patterns among Black Americans. As a result, less is known regarding which drug combinations are most common among this population and their reasons for co-using certain drugs. Therefore, the objective of this mixed methods study was to identify which substances were most commonly co-used with opioids among Black Americans, while also capturing their motives for combining opioids with other drugs. This study used data from the Florida Minority Health Study, a mixed-methods project that included online surveys (n = 303) and qualitative in-depth interviews (n = 30) of Black Americans who misuse opioids. Data collection was conducted from August 2021 to February 2022 throughout Southwest Florida. Analyses revealed that opioids were most commonly combined with alcohol, cocaine, and methamphetamine, respectively. Opioids were co-used with alcohol in an attempt to enhance the desired effect (i.e., intoxication), while stimulants and opioids were combined to counteract the undesirable side effects of the other. This study begins to answer the question of which/why substances are combined with opioids among Black Americans and should inform behavioral health interventions targeted at this population. Data on this topic are especially timely as the United States goes through the current fourth wave of the opioid crisis that is characterized by deaths due to polydrug use. These findings invite further study using nationally representative data to determine the extent to which polydrug using patterns differ across racial/ethnic groups.

The influence of transformations in supply on methamphetamine initiation among people injecting opioids in the United States

BACKGROUND

Co-use of methamphetamine (MA) and opioids (pharmaceutical pills, heroin and fentanyls) has increased in the United States and is represented in rising mortality. Although coinciding with the import of low cost, high potency and purity methamphetamine, the relationship between supply and demand in propelling this polydrug use is not well understood. We consider the influence of macro changes in supply on the uptake of opioid and methamphetamine co-use by injection at the level of individual drug and injection initiation in West Virginia, a state which leads the US in drug overdose mortality.

METHOD

We recruited n = 30 people for semi-structured interviews who self-reported injecting heroin/fentanyl and using methamphetamine by any route at a West Virginia syringe service program and through snowball sampling. Interviews were recorded and transcripts analyzed using a thematic approach. Ethnographic observation was also conducted and recorded in fieldnotes. Sequence of substance and mode of use initiation and use trajectories for opioids and stimulants were charted for each participant.

RESULTS

A clear pattern of individual drug initiation emerged that matched each successive supply wave of the US overdose epidemic: 25 participants had initiated opioid use with pills, followed by heroin, often mixed with/replaced by fentanyl, and subsequently added methamphetamine use. For participants, the supply and consumption of opioid analgesics had set in motion a series of steps leading to the addition of stimulant injection to existing opioid injecting repertoires. Unlike other studies that have found a birth cohort effect in patterns of initiation, participants showed the same sequence across age groups. Considerations of economy, availability, dependence, tolerance and the erosion of taboos that marked transitions from opioid pills to heroin injection influenced these subsequent trajectories in novel ways. The form, timing and extent of opioid and stimulant consumption was influenced by four stages of the changing drug supply, which in turn reflected back on demand.

CONCLUSION

Transformations in the social meaning and supply of methamphetamine enabled these transitions while other desired, non-injectable drugs were difficult to obtain. We discuss policy implications of injectable drugs' market dominance at this location and possible interventions.

Challenges and insights: Methamphetamine analysis in post-mortem putrefied human tissues in a hot climate

Background

The production and distribution of methamphetamine (meth) is often associated with illegal and clandestine laboratories, posing significant challenges for law enforcement and public health efforts. Global concern is growing over meth-related fatalities, as its high potential for abuse and detrimental impact on health make it an important issue in the realm of substance abuse and addiction. This concern has notably increased in Saudi Arabia, where the hot climate adds complexity to the analysis due to challenges posed by putrefaction. There is still an urgent need to enhance the screening capabilities of many toxicology laboratories to determine the cause of death, whether it be due to drug use or natural causes.

Aim

This research aimed to investigate meth concentrations in post-mortem putrefied human solid tissues in a hot climate and comparing meth metabolite concentrations in cases where signs of putrefaction were observed versus those with no signs of putrefaction. The objective is to assist criminal investigations by analyzing meth and its metabolite concentrations.

Methods

This retrospective cohort study involved postmortem samples from human subjects during autopsies conducted between 2016 and 2022. It focused on analyzing meth and its metabolite concentrations using LC-MS/MS analysis. Data on demographics, medical history, age, location, putrefaction, and other drug use were retrieved from medical records.

Results

Out of the 27 reported samples of meth and its metabolite amphetamine in both putrefied and non-putrefied biological fluids and tissues, only 8 (30%) exhibited signs of putrefaction between 2016 and 2022. Despite decomposition, detectable concentrations of meth and amphetamine were sufficient to determine the cause of death and the source of amphetamines.

Conclusion

This study found no significant difference in concentrations between putrefied and non-putrefied cases, underscoring the importance of multiple sample testing during autopsy for accurate interpretation. Each case is unique and must be considered individually.

Changes in injecting versus smoking heroin, fentanyl, and methamphetamine among people who inject drugs in San Diego, California, 2020 to 2023

Background

Amidst a rapidly evolving drug supply in North America, people who inject drugs may be transitioning to smoking them. We aimed to assess changes in injecting and smoking heroin, fentanyl and methamphetamine among a cohort of people who injected drugs at baseline from San Diego, California.

Methods

Over five six-month periods spanning October 2020-April 2023, we assessed prevalence of injecting and smoking opioids or methamphetamine and whether participants used these drugs more frequently by smoking than injecting. Multivariable Poisson regression via Generalized Estimating Equations was used to examine time trends.

Results

Of 362 participants, median age was 40 years; most were male (72%), non-Hispanic (55%), and unhoused (67%). Among this cohort, of whom 100% injected (or injected and smoked) at baseline, by period five (two years later), 34% reported only smoking, while 59% injected and smoked, and 7% only injected. By period five, the adjusted relative risk (aRR) of injecting opioids was 0.41 (95% Confidence Interval [CI]: 0.33, 0.51) compared to period one, and the aRR for injecting methamphetamine was 0.50 (95% CI: 0.39, 0.63). Compared to period one, risks for smoking fentanyl rose significantly during period three (aRR=1.44, 95% CI: 1.06, 1.94), four (aRR=1.65, 95% CI: 1.24, 2.20) and five (aRR=1.90, 95% CI: 1.43, 2.53). Risks for smoking heroin and methamphetamine more frequently than injecting these drugs increased across all periods.

Conclusions

Opioid and methamphetamine injection declined precipitously, with notable increases in smoking these drugs. Research is urgently needed to understand the health consequences of these trends.

Treatment Disparities in Georgia: Methamphetamine Use Disorder

BACKGROUND

Methamphetamine use disorder (MUD) is becoming more of a public health issue in Georgia State, with health and social effects affecting both people and communities. This study aimed to investigate attributes that may affect the accessibility of treatment among the methamphetamine-use population in the state of Georgia.

METHODS

We utilized the Treatment Episode Data Set - Discharges (TEDS-D) for 2016-2020 in Georgia, comprising participants with MUD (175,270). We utilized descriptive statistics and inferential techniques to ascertain the relationship between variables. Multiple logistic regression was used to control for confounding variables at a 95% confidence interval.

RESULTS

This study's findings showed individuals aged 25-49 years had 1.8 times higher odds of getting treatment for methamphetamine use compared to those aged 12-24 years (adjusted odds ratio (AOR) = 1.8; 95% CI: 1.50-2.16). Alaska Native individuals (Aleut, Eskimo, and Indian) had 7.07 times higher odds of receiving treatment than Asian or Pacific Islander individuals (AOR = 7.07; 95% CI: 2.02-24.67). Compared to Asian or Pacific Islander individuals, Black or African American individuals had 12.11 times higher odds of receiving treatment (AOR = 12.11; 95% CI: 9.37-15.66), while White individuals had 6.82 times higher odds of getting treatment (AOR = 1.09; 95% CI: 0.86-1.37).

CONCLUSION

MUD treatment disparity challenges are revealed in our study, emphasizing the critical need for focused intervention programs.

Prevalence of fentanyl in methamphetamine and cocaine samples collected by community-based drug checking services

BACKGROUND

Overdose deaths involving stimulants and opioids simultaneously have raised the specter of widespread contamination of the stimulant supply with fentanyl.

METHODS

We quantified prevalence of fentanyl in street methamphetamine and cocaine, stratified by crystalline texture, analyzing samples sent voluntarily to a public mail-in drug checking service (May 2021-June 2023). Samples from 77 harm reduction programs and clinics originated in 25 US states. Sample donors reported expected drug and physical descriptions. Substances were identified by gas chromatography-mass spectrometry. Negative binomial models were used to calculate fentanyl prevalence, adjusting for potential confounders related to sample selection. We also examined if xylazine changed donors' accuracy of detecting fentanyl.

RESULTS

We analyzed 718 lab-confirmed samples of methamphetamine (64%) and cocaine (36%). The adjusted prevalence of fentanyl was 12.5% (95% CI: 2.2%, 22.9%) in powder methamphetamine and 14.8% (2.3%, 27.2%) in powder cocaine, with notable geographic variation. Crystalline forms of both methamphetamine (Chisq=57, p<0.001) and cocaine (Chisq=18, p<0.001) were less likely to contain fentanyl: less than 1% of crystal methamphetamine (2/276) and no crack cocaine (0/53). Heroin was present in 6.6% of powder cocaine samples. Xylazine reduced donors' ability to detect fentanyl, with correct classification dropping from 92% to 42%.

CONCLUSIONS

Fentanyl was detected primarily in powder forms of methamphetamine and cocaine. Recommended interventions include expanding community-based drug checking, naloxone and fentanyl test strip distribution for people who use stimulants , and supervised drug consumption sites. New strategies to dampen variability in street drug composition are needed to reduce inadvertent fentanyl exposure.