Receipt of COVID-19 emergency funds and engagement in sex work during COVID-19 among people who use drugs: evidence from Vancouver, Canada

BACKGROUND

During the early period of the COVID-19 pandemic, public health orders disrupted income generation in numerous sectors and many governments provided emergency financial support. Access to government support and changes in engagement in sex work during the early period of the pandemic among people who use drugs (PWUD) are not well described. In the present study, we investigate the prevalence and correlates of engaging in sex work during the COVID-19 pandemic, among PWUD in Vancouver, Canada.

METHODS

Data derived from three harmonized cohorts of PWUD. Using multivariable logistic regression, we characterized factors associated with engaging in sex work in the last month between July 17 and November 30, 2020. Reports of changes in frequency of engagement in sex work since the pandemic were also collected.

RESULTS

Of the 864 individuals included in this analysis, 55 (6.4%) reported sex work engagement in the last month. Among these participants, 40.7% reported receiving COVID-19 income support in the past month vs. 52.7% of the rest of the sample, though receipt of income support in the past six months was similar between the two groups (72.2% vs. 75.7%, p = 0.624). In multivariable analysis, receipt of financial support in the last month was negatively associated with engagement in sex work in the last month (adjusted odds ratio [AOR] = 0.44 [95% confidence interval [CI]: 0.24-0.81]). Among 69 participants who responded to a question regarding changes in engagement in sex work, 38 (55.1%) reported a decrease, 11 (15.9%) reported an increase, 19 (27.5%) reported no change, and 1 (1.4%) reported cessation.

CONCLUSIONS

Findings document that engagement in sex work appears to have declined early in the pandemic. Participants who received income support in the past month were less likely to report recent engagement in sex work. Findings suggest that recent receipt of income support may have contributed to reductions in engagement in sex work. Additional investigation is warranted.

Does This Patient Have Alcohol Use Disorder?: The Rational Clinical Examination Systematic Review

Importance

The accuracy of screening tests for alcohol use disorder (defined as a problematic pattern of alcohol use leading to clinically significant impairment or distress) requires reassessment to align with the latest definition in the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) (DSM-5).

Objective

To assess the diagnostic accuracy of screening tools in identifying individuals with alcohol use disorder as defined in the DSM-5.

Data Sources and Study Selection

The databases of MEDLINE and Embase were searched (January 2013-February 2023) for original studies on the diagnostic accuracy of brief screening tools to identify alcohol use disorder according to the DSM-5 definition. Because diagnosis of alcohol use disorder does not include excessive alcohol use as a criterion, studies of screening tools that identify excessive or high-risk drinking among younger (aged 9-18 years), older (aged ≥65 years), and pregnant persons also were retained.

Data Extraction and Synthesis

Sensitivity, specificity, and likelihood ratios (LRs) were calculated. When appropriate, a meta-analysis was performed to calculate a summary LR.

Results

Of 4303 identified studies, 35 were retained (N = 79 633). There were 11 691 individuals with alcohol use disorder or a history of excessive drinking. Across all age categories, a score of 8 or greater on the Alcohol Use Disorders Identification Test (AUDIT) increased the likelihood of alcohol use disorder (LR, 6.5 [95% CI, 3.9-11]). A positive screening result using AUDIT identified alcohol use disorder better among females (LR, 6.9 [95% CI, 3.9-12]) than among males (LR, 3.8 [95% CI, 2.6-5.5]) (P = .003). An AUDIT score of less than 8 reduced the likelihood of alcohol use disorder similarly for both males and females (LR, 0.33 [95% CI, 0.20-0.52]). The abbreviated AUDIT-Consumption (AUDIT-C) has sex-specific cutoff scores of 4 or greater for males and 3 or greater for females, but was less useful for identifying alcohol use disorder (males: LR, 1.8 [95% CI, 1.5-2.2]; females: LR, 2.0 [95% CI, 1.8-2.3]). The AUDIT-C appeared useful for identifying measures of excessive alcohol use in younger people (aged 9-18 years) and in those older than 60 years of age. For those younger than 18 years of age, the National Institute on Alcohol Abuse and Alcoholism age-specific drinking thresholds were helpful for assessing the likelihood of alcohol use disorder at the lowest risk threshold (LR, 0.15 [95% CI, 0.11-0.21]), at the moderate risk threshold (LR, 3.4 [95% CI, 2.8-4.1]), and at the highest risk threshold (LR, 15 [95% CI, 12-19]). Among persons who were pregnant and screened within 48 hours after delivery, an AUDIT score of 4 or greater identified those more likely to have alcohol use disorder (LR, 6.4 [95% CI, 5.1-8.0]), whereas scores of less than 2 for the Tolerance, Worried, Eye-Opener, Amnesia and Cut-Down screening tool and the Tolerance, Annoyed, Cut-Down and Eye-Opener screening tool identified alcohol use disorder similarly (LR, 0.05 [95% CI, 0.01-0.20]).

Conclusions and Relevance

The AUDIT screening tool is useful to identify alcohol use disorder in adults and in individuals within 48 hours postpartum. The National Institute on Alcohol Abuse and Alcoholism youth screening tool is helpful to identify children and adolescents with alcohol use disorder. The AUDIT-C appears useful for identifying various measures of excessive alcohol use in young people and in older adults.

The FASTER-BUP Study, Extended-Release Injectable Buprenorphine for the Treatment of Opioid Use Disorder Among Individuals at High Risk of Overdose: Protocol for an Observational Prospective Study

North America is facing an unprecedented public health emergency of opioid-related morbidity and mortality. The mortality benefits of oral medication treatment for opioid use disorder (MOUD), such as methadone or buprenorphine, are well documented. However, barriers to access and long-term engagement have prevented maximizing their benefits. Long-acting injectable buprenorphine formulations were developed to address some of the challenges associated with oral MOUD. The "Pilot study to assess the feasibility, efficacy, and safety of extended-release injectable buprenorphine for the treatment of opioid use disorder among individuals at high risk of overdose" (FASTER-BUP) was developed to explore this treatment option in populations at high risk of overdose in a real-world Canadian setting. FASTER-BUP is a 24-week observational prospective study evaluating the feasibility and clinical utility of extended-release injectable buprenorphine (XR-BUP) for the treatment of opioid use disorder (OUD) among 40 adults at high risk of overdose (ie, lifetime history of overdose or a positive urine drug test (UDT) for fentanyl within 30 days prior to screening) in Vancouver, BC. The primary outcome is retention in treatment and secondary outcomes include: use of unregulated opioids, safety, overdose events, treatment satisfaction, changes in drug-related problems, changes in quality of life, opioid cravings, health service utilization, and criminal activity. FASTER-BUP is the first study to explore XR-BUP among individuals at high risk of overdose in a real-world Canadian setting. This commentary provides a brief narrative about the study thus far and presents insights on key adaptations to the study protocol, including those adopted to mitigate recruitment challenges.

Patterns of Socioeconomic Marginalization among People Who Use Drugs: A Gender-Stratified Repeated Measures Latent Class Analysis

Socioeconomic factors are important correlates of drug use behaviors and health-related outcomes in people who use drugs (PWUD) residing in urban areas. However, less is known about the complex overlapping nature of socioeconomic conditions and their association with a range of individual, drug use, and health-related factors in men and women who use drugs. Data were obtained from two community-recruited prospective cohorts of PWUD. Using a gender-stratified approach, we conducted repeated measures latent class analyses (RMLCA) to identify discrete latent socioeconomic subgroups. Multivariable generalized estimating equations were then used to identify correlates of class membership. Between June 2014 and December 2018, RMLCA of 9844 observations from 1654 participants revealed five distinct patterns of socioeconomic status for both men and women. These patterns were primarily distinguished by variations in income, material and housing security, income generation activity, exposure to violence, criminal justice involvement, and police contact. Across gender, progressive increases in exposure to multiple dimensions of socioeconomic disadvantage were found to be associated with frequent use of opioids and stimulants, accessing social services, and being hepatitis C virus antibody-positive. Similar but less congruent trends across gender were observed for age, binge drug use, engagement with opioid agonist therapy, and living with HIV. Gendered patterns of multiple and overlapping dimensions of socioeconomic adversity aligned with patterns of frequent drug use and health-related concerns, highlighting priority areas for gender-inclusive, multilevel responses to mitigate health disparities and meet the diverse socioeconomic needs of urban-dwelling men and women who use drugs.

Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13  TeV and corresponding to an integrated luminosity of 137  fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst)  pb.

Sexually transmitted and blood-borne infection risk reduction with methadone and buprenorphine/naloxone among people with prescription-type opioid use disorder: Findings from a Canadian pragmatic randomized trial

INTRODUCTION

People who use drugs are disproportionally affected by sexually transmitted and blood-borne infections (STBBIs). While the benefits of methadone in reducing injecting-risk behaviours are well documented, less is known on its impacts on sexual-related risks, as well as its comparative effectiveness to buprenorphine/naloxone, particularly in the context of highly potent opioids. The aim of this study was to estimate the relative effects of buprenorphine/naloxone and methadone on injecting and STBBI risks among people with prescription-type opioid use disorder (POUD).

METHODS

Secondary analysis of a pan-Canadian pragmatic 24-week randomized clinical trial comparing methadone and buprenorphine/naloxone models of care among 272 people with POUD (including licit or illicit opioid analgesics, fentanyl). The Risk Behaviour Survey was used to collect injecting and sexual risks at baseline, and weeks 12 and 24.

RESULTS

In total, 210 participants initiated treatment (103 buprenorphine/naloxone and 107 methadone). At baseline, 113/205 (55.1%) participants reported recently injecting drugs, 37/209 (17.7%) unsafe injection practices and 67/162 (41.4%) high-risk sex. Both methadone and buprenorphine/naloxone were associated with reductions in the prevalence of injection drug use and high-risk sex at weeks 12 and 24 with no interactions between treatment arm and time.

CONCLUSION

Methadone and buprenorphine/naloxone were similarly effective in reducing injecting and sexual risk behaviours among people with POUD.

CLINICAL TRIALS REGISTRATION

clinicaltrials.gov NCT03033732.

Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector

ATLAS measured the centrality dependence of the dijet yield using 165  nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16  TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140  fb^{-1} of pp collisions at sqrt[s]=13  TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst)  fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06  fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

Longitudinal polysubstance use patterns and non-fatal overdose: A repeated measures latent class analysis

BACKGROUND

Polysubstance use (PSU) is common among people who use opioids (PWUO) and has been associated with drug-related harms. We aimed to identify latent longitudinal PSU classes among a cohort of PWUO and characterize non-fatal overdose risks among different sub-classes over time.

METHODS

We used longitudinal data (2005-2018) from three ongoing prospective cohorts of people who use drugs in Vancouver, Canada. The primary outcome of interest was self-reported non-fatal overdose during the past six months. The primary exposure of interest was longitudinal PSU patterns among PWUO, obtained from repeated measures latent class analysis (RMLCA) of weekly substance use-related outcome indicators. Multivariable generalized estimating equations models were built to assess the association between latent PSU class membership and non-fatal overdose, adjusting for potential sociodemographic, behavioural, and structural confounders.

RESULTS

2627 PWUO were included in the analysis, and 1094 (41.6 %) had experienced at least one non-fatal overdose during the study period. RMLCA revealed five distinct latent longitudinal PSU classes, including low/infrequent use (Class 1; 30 %), primarily opioid and methamphetamine use (Class 2; 22 %), primarily cannabis use (Class 3; 15 %), primarily opioid and crack use (Class 4; 29 %), and frequent PSU (Class 5; 4 %). In comparison with Class 1 (low), membership in all latent PSU classes except Class 3 (cannabis) was associated with increased odds of non-fatal overdose: Class 2 (opioids + meth) vs. Class 1 (Adjusted odds ratios [aOR] = 2.20, 95 % confidence intervals [CI]: 1.51-3.22), Class 4 (opioids + crack) vs. Class 1 (aOR = 1.06, 95 % CI: 0.85-1.33), and Class 5 (frequent) vs. Class 1 (aOR = 2.39, 95 % CI: 1.92-2.97).

CONCLUSION

Our findings highlighted the heterogeneous characteristics of PWUO in terms of patterns of PSU and non-fatal overdose risk. The diverse nature of PWUO and the potential additive or multiplicative impact of using several substances on overdoses should be reflected across the substance use treatment continuum and care provision.

Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data

A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140  fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11  GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.

Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector

A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.

Observation of Single-Top-Quark Production in Association with a Photon Using the ATLAS Detector

This Letter reports the observation of single top quarks produced together with a photon, which directly probes the electroweak coupling of the top quark. The analysis uses 139  fb^{-1} of 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. Requiring a photon with transverse momentum larger than 20 GeV and within the detector acceptance, the fiducial cross section is measured to be 688±23(stat) _{-71}^{+75}(syst)  fb, to be compared with the standard model prediction of 515_{-42}^{+36}  fb at next-to-leading order in QCD.

Evaluation of audit and feedback to family physicians on prescribing of opioid analgesics to opioid-naïve patients: A pragmatic randomized delay trial

BACKGROUND

Exposure to opioid analgesics have historically raised concern for a risk of developing opioid use disorder. Prescriber audit-and-feedback interventions may reduce opioid prescribing, but some studies have shown detrimental effects for current users. We examined the effectiveness of an audit and feedback intervention, named Portrait, to reduce initiation of opioid analgesics among opioid-naïve patients experiencing pain.

METHODS

REDONNA was a single-blinded, two-arm (Early vs Delayed mailing) randomized trial of a portrait for eligible family physicians (FPs) in British Columbia (BC), Canada. The primary outcome was the change in the number of initiations of opioid analgesic prescriptions written by FPs for acute/chronic pain management. We compared outcomes for a 6-month window before vs. after each mailed intervention, using differences in percent differences (DPD) with 95% confidence intervals (CI) and odds ratios (OR) from logistic regressions adjusted for clustering of patients by FP.

RESULTS

In the Early (n = 2260) and Delayed (n = 2156) groups, opioid initiations per month were the same in the Before (2.10 Early; 2.06 Delayed) and After (1.94 Early; 1.95 Delayed) windows. The DPD was -2.1% (CI: -4.4% to 0.3%), and ORs were: 0.98 (CI: 0.96 to 1.01) for any opioid, 0.97 (CI: 0.94 to 1.01) for codeine (62% of initiations), and 1.0 (CI: 0.97 to 1.07) for tramadol (25% of initiations). There were no differences in mean quantity of tablets, mean milligrams of morphine equivalents (MME), or mean number of days.

CONCLUSION

Portrait had no impact on FPs' rates of prescribing opioid analgesics to opioid-naïve patients experiencing pain.

TRIAL REGISTRATION

The study was registered prospectively on 30 March 2020 at the ISRCTN Register (https://www.isrctn.com/ISRCTN34246811).

Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02  TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72  nb^{-1} and 257  pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158 Collapse

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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13  TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8  pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

Temporal Structures in Positron Spectra and Charge-Sign Effects in Galactic Cosmic Rays

We present the precision measurements of 11 years of daily cosmic positron fluxes in the rigidity range from 1.00 to 41.9 GV based on 3.4×10^{6} positrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The positron fluxes show distinctly different time variations from the electron fluxes at short and long timescales. A hysteresis between the electron fluxes and the positron fluxes is observed with a significance greater than 5σ at rigidities below 8.5 GV. On the contrary, the positron fluxes and the proton fluxes show similar time variation. Remarkably, we found that positron fluxes are modulated more than proton fluxes with a significance greater than 5σ for rigidities below 7 GV. These continuous daily positron fluxes, together with AMS daily electron, proton, and helium fluxes over an 11-year solar cycle, provide unique input to the understanding of both the charge-sign and mass dependencies of cosmic rays in the heliosphere.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

Observation of the γγ→ττ Process in Pb+Pb Collisions and Constraints on the τ-Lepton Anomalous Magnetic Moment with the ATLAS Detector

This Letter reports the observation of τ-lepton-pair production in ultraperipheral lead-lead collisions Pb+Pb→Pb(γγ→ττ)Pb and constraints on the τ-lepton anomalous magnetic moment a_{τ}. The dataset corresponds to an integrated luminosity of 1.44  nb^{-1} of LHC Pb+Pb collisions at sqrt[s_{NN}]=5.02  TeV recorded by the ATLAS experiment in 2018. Selected events contain one muon from a τ-lepton decay, an electron or charged-particle track(s) from the other τ-lepton decay, little additional central-detector activity, and no forward neutrons. The γγ→ττ process is observed in Pb+Pb collisions with a significance exceeding 5 standard deviations and a signal strength of μ_{ττ}=1.03_{-0.05}^{+0.06} assuming the standard model value for a_{τ}. To measure a_{τ}, a template fit to the muon transverse-momentum distribution from τ-lepton candidates is performed, using a dimuon (γγ→μμ) control sample to constrain systematic uncertainties. The observed 95% confidence-level interval for a_{τ} is -0.057 Collapse

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Longitudinal latent polysubstance use patterns among a cohort of people who use opioids in Vancouver, Canada

INTRODUCTION

Polysubstance use (PSU) practices are increasing among people who use opioids (PWUO). However, several aspects of longitudinal PSU patterns among PWUO remain understudied. This study aims to identify person-centred longitudinal patterns of PSU among a cohort of PWUO.

METHODS

Using longitudinal data (2005-2018) from three prospective cohort studies including people who use drugs in Vancouver, Canada, we used repeated measures latent class analysis to identify different PSU classes among PWUO. Multivariable generalised estimating equations models weighted by the respective posterior membership probabilities were applied to identify covariates of membership in different PSU classes over time.

RESULTS

Overall, 2627 PWUO (median age at baseline: 36 [quartile 1-3: 25-45]) were included between 2005 and 2018. We found five distinct PSU patterns, including low/infrequent probability of regular substance use (Class 1; 30%), primarily opioid and methamphetamine use (Class 2; 22%), primarily cannabis use (Class 3; 15%), primarily opioid and crack use (Class 4; 29%) and frequent PSU (Class 5; 4%). Membership in Class 2, 4 and 5 was positively associated with several behavioural and socio-structural adversities.

DISCUSSION AND CONCLUSIONS

Findings of this longitudinal study suggest PSU is the norm among PWUO and highlights the heterogeneous characteristics of PWUO. The diversities within the population of PWUO need to be recognised in addiction care and treatment as well as optimising resource allocation in the response to the overdose crisis.

miR-146a aggravates cognitive impairment and Alzheimer disease-like pathology by triggering oxidative stress through MAPK signaling

INTRODUCTION

Mir-146a-5p has been widely recognized as a critical regulatory element in the immune response. However, recent studies have shown that miR-146a-5p may also be involved in the development of Alzheimer disease (AD). Regrettably, the related mechanisms are poorly understood. Here, we investigated the effects of miR-146a in mice models and SH-SY5Y cells treated with amyloid β (Aβ)1-42.

METHODS

To create a model of AD, SH-SY5Y cells were treated with Aβ1-42 and mice received intracerebroventricular injections of Aβ1-42. Then, the transcriptional levels of miR-146a were estimated by real-time PCR. We transiently transfected the miR-146a-5p mimic/inhibitor into cells and mice to study the role of miR-146a. The role of signaling pathways including p38 and reactive oxygen species (ROS) was studied by using specific inhibitors. Aβ and amyloid-beta precursor protein (APP)levels were measured by immunoblotting. Furthermore, Aβ expression was analyzed by immunofluorescence and histochemical examinations.

RESULTS

Aβ1-42-stimulated SH-SY5Y cells displayed increased transcriptional levels of miR-146a and APP. Moreover, the p38 MAPK signaling pathway and ROS production were activated upon stimulation with a miR-146a-5p mimic. However, treatment with a miR-146a-5p inhibitor decreased the levels of APP, ROS, and p-p38 MAPK. A similar phenomenon was also observed in the animals treated with Aβ1-42, in which miR-146a upregulation increased the expression of Aβ, p-p38, and ROS, while the inhibition of miR-146a had the opposite effect. This suggests that miR-146a increases Aβ deposition and ROS accumulation via the p-p38 signaling pathway.

CONCLUSIONS

Our research demonstrates that miR-146a-5pa increases Aβ deposition by triggering oxidative stress through activation of MAPK signaling.

Police seizure of drugs without arrest among people who use drugs in Vancouver, Canada, before provincial 'decriminalization' of simple possession: a cohort study

BACKGROUND

Several jurisdictions in Canada have recently considered decriminalizing possession of illicit drugs for personal use (henceforth, simple possession) as part of their responses to the ongoing drug toxicity/overdose crisis. In this context, we sought to examine an early implementation case of a de facto depenalization policy of simple possession offences in Vancouver, Canada, that was enacted in 2006. Specifically, we characterized experiences of people who use drugs (PWUD) whose drugs were discretionally seized by police without arrest.

METHODS

Data were derived from three prospective cohorts of community-recruited PWUD in Vancouver over 16 months in 2019-2021. We conducted multivariable generalized estimating equations analyses to determine the prevalence of and factors associated with drug seizure. Sub-analyses used data collected in 2009-2012 and examined the trends over time.

RESULTS

Among 995 participants who were interviewed in 2019-2021, 63 (6.3%) had their drugs seized by police at least once in the past 6 months. In multivariable analyses, factors significantly associated with drug seizure included: homelessness (adjusted odds ratio [AOR]: 1.98; 95% confidence interval [CI] 1.09-3.61), working in the unregulated drug market (AOR: 4.93; 95% CI 2.87-8.49), and naloxone administration (AOR: 2.15; 95% CI 1.23-3.76). In 2009-2012, 67.8% reported having obtained new drugs immediately after having their drugs seized by police. Odds of drug seizure were not significantly different between the two time periods (2019-2021 vs. 2009-2012) (AOR: 0.93; 95% CI: 0.64-1.35).

CONCLUSIONS

Despite the depenalization policy, the Vancouver Police Department has continued to seize illicit drugs from PWUD, even in cases where no arrest occurred. This policing practice may create health and safety risks for PWUD as it forces PWUD to increase the engagement with the unregulated illicit drug market. Our findings support calls for abolishing this often-undocumented discretionary policing practice that may exacerbate ongoing health inequities and interfere with peer-based overdose prevention efforts.

Strong Constraints on Jet Quenching in Centrality-Dependent p+Pb Collisions at 5.02 TeV from ATLAS

Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including pp and p+Pb collisions. In contrast, while jet quenching is observed in Pb+Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36  nb^{-1} of p+Pb and 3.6  pb^{-1} of pp collisions at 5.02 TeV. The yields of charged hadrons with p_{T}^{ch}>0.5  GeV near and opposite in azimuth to jets with p_{T}^{jet}>30 or 60 GeV, and the ratios of these yields between p+Pb and pp collisions, I_{pPb}, are reported. The collision centrality of p+Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The I_{pPb} values are consistent with unity within a few percent for hadrons with p_{T}^{ch}>4  GeV at all centralities. These data provide new, strong constraints that preclude almost any parton energy loss in central p+Pb collisions.

Search for Heavy Neutral Leptons in Decays of W Bosons Using a Dilepton Displaced Vertex in sqrt[s]=13 TeV pp Collisions with the ATLAS Detector

A search for a long-lived, heavy neutral lepton (N) in 139  fb^{-1} of sqrt[s]=13  TeV pp collision data collected by the ATLAS detector at the Large Hadron Collider is reported. The N is produced via W→Nμ or W→Ne and decays into two charged leptons and a neutrino, forming a displaced vertex. The N mass is used to discriminate between signal and background. No signal is observed, and limits are set on the squared mixing parameters of the N with the left-handed neutrino states for the N mass range 3  GeV Collapse

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Test of CP Invariance in Higgs Boson Vector-Boson-Fusion Production Using the H→γγ Channel with the ATLAS Detector

A test of CP invariance in Higgs boson production via vector-boson fusion has been performed in the H→γγ channel using 139  fb^{-1} of proton-proton collision data at sqrt[s]=13  TeV collected by the ATLAS detector at the LHC. The optimal observable method is used to probe the CP structure of interactions between the Higgs boson and electroweak gauge bosons, as described by an effective field theory. No sign of CP violation is observed in the data. Constraints are set on the parameters describing the strength of the CP-odd component in the coupling between the Higgs boson and the electroweak gauge bosons in two effective field theory bases: d[over ˜] in the HISZ basis and c_{HW[over ˜]} in the Warsaw basis. The results presented are the most stringent constraints on CP violation in the coupling between Higgs and weak bosons. The 95% C.L. constraint on d[over ˜] is derived for the first time and the 95% C.L. constraint on c_{HW[over ˜]} has been improved by a factor of 5 compared to the previous measurement.

Crystal methamphetamine use and methadone maintenance treatment dissatisfaction: A prospective cohort study in Vancouver, Canada

BACKGROUND

Patient satisfaction is key to the success of methadone maintenance treatment (MMT), and yet how MMT satisfaction is affected by the increasingly common use of crystal methamphetamine among people receiving opioid treatment remains poorly understood. We aimed to assess the association between crystal methamphetamine use and MMT dissatisfaction.

METHODS

We employed generalized estimating equations to examine the relationship between crystal methamphetamine use and MMT dissatisfaction among patients receiving MMT within two prospective cohorts in Vancouver, Canada, between December 2016 and March 2020.

RESULTS

Of the 836 participants receiving MMT, the median age was 47 years, and 55.3 % self-identified as male at baseline. In a multivariable model, those reporting more than weekly crystal methamphetamine use were more likely to report MMT dissatisfaction (Odds ratio: 1.40, 95 % confidence interval: 1.05-1.86) compared to those reporting less than monthly crystal methamphetamine use.

CONCLUSIONS

Among our sample of people receiving MMT, we noted a positive association of frequent crystal methamphetamine use with MMT dissatisfaction. Our study suggests a need for novel strategies to better understand and address frequent methamphetamine use among those receiving MMT, particularly given recent shifts in substance use patterns involving the rising co-use of methamphetamines and opioids.

Trends in cocaine and crystal methamphetamine injection over time in a Canadian setting between 2008 and 2018

OBJECTIVE

Unregulated stimulant use is rising globally, though trends in use of cocaine and crystal methamphetamine (CM), the two most commonly used unregulated stimulants in North America, are poorly characterized in many settings. In this study we examined patterns and associations between the injection of cocaine and CM over time in an urban Canadian setting.

METHODS

The study collected data from two prospective cohorts of people who inject drugs in Vancouver, Canada, between 2008 and 2018. We applied a time series analysis, using multivariable linear regression to detect relationships between reported CM and cocaine injection and year, controlling for covariates. The study used cross-correlation to evaluate the relative trajectories of each substance over time.

RESULTS

Among 2056 participants, per annum rates of reported injection cocaine use declined significantly over the duration of this study from 45 % to 18 % (p < 0.001), while rates of CM injection increased from 17 % to 32 % (p < 0.001). Multivariable linear regression showed that recent CM injection was negatively associated with recent cocaine injection (β = -0.609, 95 % CI = -0.750, -0.467). Cross-correlation demonstrated that injection CM use was associated with a decrease in the likelihood of cocaine injection 12 months later (p = 0.002).

CONCLUSIONS

These findings demonstrate an epidemiological shift in patterns of injection stimulant use, with rising CM injection associated with a corresponding decrease in cocaine injection over time. Strategies are urgently needed that help to treat and reduce harm among the growing population of people who inject CM.

Experiences of violence during the COVID-19 pandemic among people who use drugs in a Canadian setting: a gender-based cross-sectional study

OBJECTIVES

People who use drugs (PWUD) experience disproportionately high rates of violent victimization. Emerging research has demonstrated that the COVID-19 pandemic has exacerbated violence against some priority populations (e.g., women), however there is limited research examining the impact of the pandemic on the experiences of violence of PWUD.

METHODS

Using data collected between July and November 2020 from three prospective cohort studies of PWUD in Vancouver, Canada, we employed multivariable logistic regression stratified by gender to identify factors associated with recent experiences of violence, including the receipt of COVID-19 emergency income support.

RESULTS

In total, 77 (17.3%) of 446 men, and 54 (18.8%) of 288 women experienced violence in the previous six months. Further, 33% of men and 48% of women who experienced violence reported that their experience of violence was intensified since the COVID-19 pandemic began. In the multivariable analyses, sex work (Adjusted Odds Ratio [AOR] = 2.15, 95% confidence interval [CI]: 1.06-4.35) and moderate to severe anxiety or depression (AOR = 3.00, 95% CI: 1.37-6.57) were associated with experiencing violence among women. Among men, drug dealing (AOR = 1.93, 95%CI: 1.10-3.38), street-based income sources (AOR = 1.93, 95%CI: 1.10-3.38), homelessness (AOR = 2.54, 95%CI: 1.40-4.62), and regular employment (AOR = 2.97, 95% CI: 1.75-5.04) were associated with experiencing violence.

CONCLUSION

Our study results suggest economic conditions and gender were major factors associated with experiencing violence among our sample of PWUD during COVID-19. These findings highlight criminalization of drug use and widespread socioeconomic challenges as barriers to addressing violence among PWUD during periods of crisis.

Properties of Cosmic-Ray Sulfur and Determination of the Composition of Primary Cosmic-Ray Carbon, Neon, Magnesium, and Sulfur: Ten-Year Results from the Alpha Magnetic Spectrometer

We report the properties of primary cosmic-ray sulfur (S) in the rigidity range 2.15 GV to 3.0 TV based on 0.38×10^{6} sulfur nuclei collected by the Alpha Magnetic Spectrometer experiment (AMS). We observed that above 90 GV the rigidity dependence of the S flux is identical to the rigidity dependence of Ne-Mg-Si fluxes, which is different from the rigidity dependence of the He-C-O-Fe fluxes. We found that, similar to N, Na, and Al cosmic rays, over the entire rigidity range, the traditional primary cosmic rays S, Ne, Mg, and C all have sizeable secondary components, and the S, Ne, and Mg fluxes are well described by the weighted sum of the primary silicon flux and the secondary fluorine flux, and the C flux is well described by the weighted sum of the primary oxygen flux and the secondary boron flux. The primary and secondary contributions of the traditional primary cosmic-ray fluxes of C, Ne, Mg, and S (even Z elements) are distinctly different from the primary and secondary contributions of the N, Na, and Al (odd Z elements) fluxes. The abundance ratio at the source for S/Si is 0.167±0.006, for Ne/Si is 0.833±0.025, for Mg/Si is 0.994±0.029, and for C/O is 0.836±0.025. These values are determined independent of cosmic-ray propagation.

Perceived Mistreatment in Health Care Settings and its Relationship with HIV Clinical Outcomes in HIV-positive People who Use Drugs in Vancouver, Canada

People living with HIV (PLWH) often experience stigma and discrimination by health care professionals. We investigated the prevalence of perceived mistreatment in health care settings and its associations with HIV clinical outcomes and health care-seeking behaviour using data from a long-running prospective cohort of PLWH who use drugs. Of the 857 participants included, 19% reported at least one instance of perceived mistreatment during the study period. In adjusted longitudinal analyses, perceived mistreatment was positively associated with not being on ART in the same follow-up period, and participants who reported perceived mistreatment were less likely to report seeing a physician in the subsequent follow-up period. Daily use of injection drugs was positively associated with reporting perceived mistreatment. These findings demonstrate the implications of negative health care interactions in a population that must consistently engage with the health care system, and the need for stigma-reducing educational interventions for health care professionals.

Re-incarceration and associated social, structural and behavioural factors among people who use drugs in an urban Canadian setting

BACKGROUND

People who use drugs (PWUD) are disproportionately incarcerated, however little is known about specific substance use, social and structural factors associated with re-incarceration among PWUD. We aimed to identify the socio-structural and substance use factors associated with re-incarceration among structurally-marginalized PWUD.

METHODS

We used longitudinal data from two prospective cohorts of PWUD in Vancouver, Canada. We included adults reporting at least one incarceration event in the last six months and who completed at least one additional follow-up study visit. We performed multivariable extended Cox regression to explore factors associated with re-incarceration.

RESULTS

Among 468 eligible participants, the median age was 40 years (Q1-Q3 = 34-46 years), 346 (73.9%) were men, 177 (37.8%) identified as Indigenous, and 227 (48.5%) experienced at least one re-incarceration event. Incidence rate of re-incarceration was 157 incarceration events per 1000 person years. In multivariable analyses, homelessness (adjusted hazard ratio [AHR] = 2.17; 95% confidence interval [95% CI]: 1.79-2.61), community judicial supervision (AHR = 3.89; 95% CI: 3.21-4.71) and re-incarceration during the study period (once: AHR = 1.95, 95% CI: 1.55-2.44; two or more events: AHR = 1.53, 95% CI: 1.23-1.90) were positively associated with re-incarceration. Among substance use variables that included illicit drugs, only heavy alcohol use remained significantly associated with re-incarceration across analyses after adjustment (AHR = 1.32; 95% CI: 1.06-1.65). Engagement in addiction treatment (AHR = 0.63; 95% CI: 0.53-0.75), mental illness (AHR = 0.70; 95% CI: 0.59-0.84) and age (AHR = 0.96; 95% CI: 0.95-0.97) were negatively associated with re-incarceration.

CONCLUSION

Access to housing and substance use services, including treatment for alcohol use disorder, following incarceration may reduce re-incarceration among PWUD. The high rates of re-incarceration of PWUD in our sample underscores how structural factors-such as homelessness and criminalization of substance use-drive re-incarceration among PWUD.

Factors associated with improvements in symptoms of anxiety and depression among gay, bisexual and other men who have sex with men (gbMSM) in Vancouver, Canada: A prospective cohort study

BACKGROUND

Depression and anxiety are commonly experienced among gay, bisexual and other men-who-have-sex-with-men (gbMSM). We explored factors associated with improvements in mental health symptoms among gbMSM with abnormal depression and anxiety scores over a period of four years, in Vancouver, Canada.

METHODS

Sexually active gbMSM ≥16 years of age were recruited using respondent-driven sampling from February 2012 to February 2015. Participants completed a computer-assisted questionnaire which included the Hospital Anxiety and Depression Scale (HADS), and psychometric scales to measure loneliness, self-esteem and social connectedness, every 6 months until July 2019. Generalized linear mixed models were used to assess factors associated with normal/borderline HADS scores (<11) following a previous abnormal score (≥11) for each of anxiety and depression subscales.

RESULTS

We recruited 694 participants, of whom 580 had at least one follow-up visit. Across all visits, 43.6 % of participants ever had abnormal anxiety scores and 16.2 % ever had abnormal depression scores. Among those with abnormal anxiety scores, 34.9 % of follow-up visits demonstrated reductions in anxiety scores. Among those with abnormal depression scores 51.0 % of follow-up visits demonstrated reductions in depression scores. Reductions in anxiety scores were associated with increased self-esteem, decreased loneliness and the number of gbMSM seen/spoken to in the previous month. Reductions in depression scores were associated with increased self-esteem, decreased loneliness and having a regular partner.

CONCLUSION

Improvements in mental health symptoms were frequently observed. Social connectedness was related with improved anxiety and depression symptoms. Interventions to improve social connectedness may help to improve mental health for gbMSM.

Temporal Structures in Electron Spectra and Charge Sign Effects in Galactic Cosmic Rays

We present the precision measurements of 11 years of daily cosmic electron fluxes in the rigidity interval from 1.00 to 41.9 GV based on 2.0×10^{8} electrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The electron fluxes exhibit variations on multiple timescales. Recurrent electron flux variations with periods of 27 days, 13.5 days, and 9 days are observed. We find that the electron fluxes show distinctly different time variations from the proton fluxes. Remarkably, a hysteresis between the electron flux and the proton flux is observed with a significance of greater than 6σ at rigidities below 8.5 GV. Furthermore, significant structures in the electron-proton hysteresis are observed corresponding to sharp structures in both fluxes. This continuous daily electron data provide unique input to the understanding of the charge sign dependence of cosmic rays over an 11-year solar cycle.

Examining the impacts of a syphilis awareness campaign among gay, bisexual, and other men who have sex with men (gbMSM) in British Columbia, Canada

OBJECTIVES

Syphilis rates have increased in BC and disproportionately affect gay, bisexual, and other men who have sex with men (gbMSM). A social marketing campaign (Syphistory) ran from January to September 2017 with the primary goal of increasing syphilis knowledge and a secondary goal of increasing syphilis screening among gbMSM in BC.

METHODS

We used pre- and post-campaign surveys to assess changes in syphilis knowledge from a convenience sample of clients attending STI clinics using one-sided t-tests. We used online Piwik metrics to examine the campaign reach, and provincial testing data to examine trends in syphilis screening. We used data from the Engage Study to examine factors associated with campaign awareness and associations with syphilis testing.

RESULTS

Of the 2155 visitors to the Syphistory website with known geography, 79.4% were from BC. Moreover, STI clinic participants who saw the campaign demonstrated a greater knowledge of syphilis (9.7/12, 80.8%) than those who did not see the campaign (mean 8.9/12, 74%) (p < 0.001). Provincial syphilis testing rates were 8764 and 9749 in the 12 months before and after the campaign; however, we did not find an overall trend in testing before versus after the campaign (p = 0.147). Among Engage participants, 12.7% reported seeing the campaign and we found an association between campaign exposure and recent syphilis testing (aOR = 2.73; 95% CI = 1.51, 4.93).

CONCLUSION

gbMSM who saw the campaign were more likely to report being tested for syphilis in the previous 6 months. STI clinic attendees who reported seeing the campaign also had higher syphilis knowledge compared to those who did not.

The impact of the COVID-19 pandemic on access to supervised consumption programs

BACKGROUND

Supervised consumption sites (SCS) and overdose prevention sites (OPS) have been increasingly implemented in response to the ongoing overdose epidemic in Canada. Although there has been a dramatic increase in overdose deaths since the start of the SARS-CoV 2 (COVID-19) pandemic, little is known about how SCS access may have been affected by this pandemic. Therefore, we sought to characterize potential changes in access to SCS during the COVID-19 pandemic among people who use drugs (PWUD) in Vancouver, Canada.

METHODS

Between June and December 2020, data were collected through the Vancouver Injection Drug Users Study (VIDUS) and the AIDS Care Cohort to Evaluate Exposure to Survival Services (ACCESS), two cohort studies involving people who use drugs. Multivariable logistic regression was used to examine individual, social and structural factors associated with self-reported reduced frequency of SCS/OPS use since COVID-19.

RESULTS

Among 428 participants, 223 (54.7%) self-identified as male. Among all individuals surveyed, 63 (14.8%) reported a decreased frequency of use of SCS/OPS since COVID-19. However, 281 (66%) reported that they "did not want to" access SCS in the last 6 months. In multivariable analyses, younger age, self-reported fentanyl contamination of drugs used and reduced ease of access to SCS/OPS since COVID-19 were positively associated with a decreased frequency of use of SCS/OPS since COVID-19 (all p < 0.05).

CONCLUSIONS

Approximately 15% of PWUD who accessed SCS/OPS reported reduced use of these programs during the COVID-19 pandemic, including those at heightened risk of overdose due to fentanyl exposure. Given the ongoing overdose epidemic, efforts must be made to remove barriers to SCS access throughout public health crises.

Association of sex work and social-structural factors with non-fatal overdose among women who use drugs in Vancouver, Canada

BACKGROUND

Women who use drugs (WWUD) and engage in sex work experience disproportionate sex- and drug-related harms, such as HIV, however comparatively little is known about their overdose risk. Therefore, we examined the association between sex work and overdose and secondarily explored the association of social-structural factors, such as policing and gendered violence, with overdose.

METHODS

Data were derived from two community cohort studies based in Vancouver, Canada between 2005 to 2018. We used logistic regression with GEE to examine the associations between a) sex work and nonfatal overdose and b) social-structural and individual variables with overdose among WWUD who engaged in sex work during the study. Sex work, overdose, and other variables were time-updated, captured every six months.

RESULTS

Among 857 WWUD included, 56% engaged in sex work during the study. Forty-three percent of WWUD engaged in sex work had at least one overdose compared to 26% of WWUD who did not. Sex work was not significantly associated with an increased odds of overdose (AOR = 1.14, 95% CI: 0.93-1.40). In the exploratory analysis amongst 476 WWUD engaged in sex work, social-structural variables associated with overdose in the multivariable model included exposure to: punitive policing (OR = 1.97, 95% CI: 1.30-2.96) and physical or sexual violence (OR = 2.55, 95% CI: 1.88-3.46).

CONCLUSIONS

WWUD engaged in sex work had an increased overdose burden that may be driven by social-structural factors rather than sex work itself. Interventions that address policing and gendered violence represent potential targets for effective overdose prevention.

Development and validation of risk prediction models for stroke and mortality among patients with type 2 diabetes in northern China

BACKGROUND

Stroke is one of the leading causes of disability and mortality in patients with type 2 diabetes mellitus (T2DM). Risk models have been developed for predicting stroke and stroke-associated mortality among patients with T2DM. Here, we evaluated risk factors of stroke for individualized prevention measures in patients with T2DM in northern China.

METHODS

In the community-based Tianjin Chronic Disease Cohort study, 58,042 patients were enrolled between January 2014 and December 2019. We used multiple imputation (MI) to impute missing variables and univariate and multivariate Cox's proportional hazard regression to screen risk factors of stroke. Furthermore, we established and validated first-ever prediction models for stroke (Model 1 and Model 2) and death from stroke (Model 3) and evaluated their performance.

RESULTS

In the derivation and validation groups, the area under the curves (AUCs) of Models 1-3 was better at 5 years than at 8 years. The Harrell's C-index for all models was above 0.7. All models had good calibration, discrimination, and clinical net benefit. Sensitivity analysis using the MI dataset indicated that all models had good and stable prediction performance.

CONCLUSION

In this study, we developed and validated first-ever risk prediction models for stroke and death from stroke in patients with T2DM, with good discrimination and calibration observed in all models. Based on lifestyle, demographic characteristics, and laboratory examination, these models could provide multidimensional management and individualized risk assessment. However, the models developed here may only be applicable to Han Chinese.

Comprehensive needle and syringe program and opioid agonist therapy reduce HIV and hepatitis c virus acquisition among people who inject drugs in different settings: A pooled analysis of emulated trials

BACKGROUND AND AIMS

Although the Netherlands, Canada and Australia were early adopters of harm reduction for people who inject drugs (PWID), their respective HIV and hepatitis C (HCV) epidemics differ. We measured the pooled effect of needle and syringe program (NSP) and opioid agonist therapy (OAT) participation on HIV and HCV incidence in these settings.

DESIGN

For each cohort, we emulated the design and statistical analysis of a target trial using observational data.

SETTING AND PARTICIPANTS

We included PWID at risk of HIV or HCV infection from the Amsterdam Cohort Studies (1985-2013), Vancouver Injection Drug Users Study (1997-2009) and Melbourne Injecting Drug User Cohort Study (SuperMIX) (2010-2021).

MEASUREMENTS

Separately for each infection and cohort (only HCV in SuperMIX), marginal structural models were used to compare the effect of comprehensive (on OAT and 100% NSP coverage or on OAT only if no recent injection drug use) versus no/partial NSP/OAT (no OAT and/or <100% NSP coverage) participation. Pooled hazard ratios (HR) and 95% CI were calculated using random-effects meta-analysis.

FINDINGS

We observed 94 HIV seroconversions and 81 HCV seroconversions among 2023 and 430 participants, respectively. Comprehensive NSP/OAT led to a 41% lower risk of HIV acquisition (pooled HR = 0.59, 95% CI = 0.36-0.96) and a 76% lower risk of HCV acquisition (pooled HR = 0.24, 95% CI = 0.11-0.51), compared with no/partial NSP/OAT, with little heterogeneity between studies for both infections (I²  = 0%).

CONCLUSIONS

In the Netherlands, Canada and Australia, comprehensive needle and syringe program and opioid agonist therapy participation appears to substantially reduce HIV and hepatitis C acquisition compared with no or partial needle and syringe program/opioid agonist therapy participation. These findings from an emulated trial design reinforce the critical role of comprehensive access to harm reduction in optimizing infection prevention for people who inject drugs.

Treatment interruptions and community connectedness among gbMSM living with HIV in Metro Vancouver, Canada

HIV treatment interruptions are a major public health concern that demonstrate a lack of engagement in care and is detrimental to the health of people living with HIV. Community connectedness have demonstrated a protective effect for psychosocial health but are not well understood for HIV treatment outcomes. We explored associations between community connectedness and treatment interruptions among gay, bisexual and other men who have sex with men (gbMSM) living with HIV in Vancouver, British Columbia. We analyzed survey data from the Momentum Health Study and identified treatment interruptions through data linkages with the provincial HIV Drug Treatment Program as episodes lasting more than 60 days beyond an expected antiretroviral therapy refill date from February 2012 to July 2019. We built a mixed-effects logistic regression model, adjusting for confounders. Of 213 gbMSM living with HIV, 54 experienced treatment interruption (25.4%) over a median five-year follow-up. Multivariable results found the number gbMSM who spoken to in the past month (aOR = 0.995; 95% CI = 0.991, 1.000 (per 100-unit increase)) and attending a gay community meeting more than once per month (aOR = 0.32; 95% CI = 0.11, 0.89) were associated with lower odds of treatment interruptions. These results highlight the importance of social connections in facilitating effective HIV care.

Discontinuation and tapering of prescribed opioids and risk of overdose among people on long-term opioid therapy for pain with and without opioid use disorder in British Columbia, Canada: A retrospective cohort study

BACKGROUND

The overdose crisis in North America has prompted system-level efforts to restrict opioid prescribing for chronic pain. However, little is known about how discontinuing or tapering prescribed opioids for chronic pain shapes overdose risk, including possible differential effects among people with and without concurrent opioid use disorder (OUD). We examined associations between discontinuation and tapering of prescribed opioids and risk of overdose among people on long-term opioid therapy for pain, stratified by diagnosed OUD and prescribed opioid agonist therapy (OAT) status.

METHODS AND FINDINGS

For this retrospective cohort study, we used a 20% random sample of residents in the provincial health insurance client roster in British Columbia (BC), Canada, contained in the BC Provincial Overdose Cohort. The study sample included persons aged 14 to 74 years on long-term opioid therapy for pain (≥90 days with ≥90% of days on therapy) between October 2014 and June 2018 (n = 14,037). At baseline, 7,256 (51.7%) persons were female, the median age was 55 years (quartile 1-3: 47-63), 227 (1.6%) persons had been diagnosed with OUD (in the past 3 years) and recently (i.e., in the past 90 days) been prescribed OAT, and 483 (3.4%) had been diagnosed with OUD but not recently prescribed OAT. The median follow-up duration per person was 3.7 years (quartile 1-3: 2.6-4.0). Marginal structural Cox regression with inverse probability of treatment weighting (IPTW) was used to estimate the effect of prescribed opioid treatment for pain status (discontinuation versus tapered therapy versus continued therapy [reference]) on risk of overdose (fatal or nonfatal), stratified by the following groups: people without diagnosed OUD, people with diagnosed OUD receiving OAT, and people with diagnosed OUD not receiving OAT. In marginal structural models with IPTW adjusted for a range of demographic, prescription, comorbidity, and social-structural exposures, discontinuing opioids (i.e., ≥7-day gap[s] in therapy) was associated with increased overdose risk among people without OUD (adjusted hazard ratio [AHR] = 1.44; 95% confidence interval [CI] 1.12, 1.83; p = 0.004), people with OUD not receiving OAT (AHR = 3.18; 95% CI 1.87, 5.40; p < 0.001), and people with OUD receiving OAT (AHR = 2.52; 95% CI 1.68, 3.78; p < 0.001). Opioid tapering (i.e., ≥2 sequential decreases of ≥5% in average daily morphine milligram equivalents) was associated with decreased overdose risk among people with OUD not receiving OAT (AHR = 0.31; 95% CI 0.14, 0.67; p = 0.003). The main study limitations are that the outcome measure did not capture overdose events that did not result in a healthcare encounter or death, medication dispensation may not reflect medication adherence, residual confounding may have influenced findings, and findings may not be generalizable to persons on opioid therapy in other settings.

CONCLUSIONS

Discontinuing prescribed opioids was associated with increased overdose risk, particularly among people with OUD. Prescribed opioid tapering was associated with reduced overdose risk among people with OUD not receiving OAT. These findings highlight the need to avoid abrupt discontinuation of opioids for pain. Enhanced guidance is needed to support prescribers in implementing opioid therapy tapering strategies with consideration of OUD and OAT status.

Opioid agonist therapy engagement and crystal methamphetamine use: The impact of unregulated opioid use in Vancouver, Canada

BACKGROUND

Crystal methamphetamine use has substantially increased among people who use opioids in recent years, yet the impact of opioid agonist therapy (OAT) on crystal methamphetamine use remains poorly characterized. Therefore, we sought to examine the relationship between OAT engagement and crystal methamphetamine use and to assess if this relationship differs according to the ongoing use of unregulated opioids.

METHODS

Data was collected from two harmonized ongoing prospective cohorts of people who use drugs in Vancouver, Canada, between December 2005 and March 2020. We employed multivariable generalized estimating equations to study the relationship between OAT engagement and crystal meth use stratified by ongoing unregulated opioid use.

RESULTS

Of 1742 participants who reported frequent opioid use at baseline, the median age was 42 years, and 61.3% were male. Multivariable analyses showed that compared to those who had not received OAT for at least one year: in the absence of ongoing unregulated opioid use, individuals who recently discontinued (adjusted Odds Ratio [aOR] = 0.47, 95% CI = 0.27-0.79), newly initiated (aOR = 0.52, 95% CI = 0.31-0.89), or were retained on OAT (aOR = 0.48, 95% CI = 0.31-0.72) reported a lower frequency of crystal methamphetamine use; in the presence of ongoing unregulated opioid use, individuals who newly initiated OAT reported a greater crystal methamphetamine use frequency (aOR = 1.24, 95% CI = 1.02-1.51).

CONCLUSIONS

We demonstrated a differential relationship between OAT engagement and crystal methamphetamine use that was conditional on the ongoing use of unregulated opioids. Our findings highlight the complexity of OAT implementation and suggest that polysubstance use patterns should be an important consideration for care providers when devising comprehensive treatment strategies and prognosticating treatment effects.

Difficulty accessing supervised consumption services during the COVID-19 pandemic among people who use drugs in Vancouver, Canada

BACKGROUND

The overdose crisis in Canada has worsened since the emergence of the COVID-19 pandemic. Although this trend is thought to be driven in part by closures or reduced capacity of supervised consumption services (SCS), little is known about the factors that may impede access to such services during the COVID-19 pandemic among people who use drugs. This study sought to characterize the prevalence and correlates of having difficulty accessing SCS during the COVID-19 pandemic among people who use drugs in Vancouver, Canada.

METHODS

Cross-sectional data from two open prospective cohorts of people who use drugs were collected via phone or videoconferencing interviews conducted between July 2020 and November 2020. Multivariable logistic regression analyses were used to examine factors associated with experiencing difficulty accessing SCS.

RESULTS

Among the 428 people who use drugs who participated in the study, 223 (54.7%) self-identified as men and the median age was 51 years (1st to 3rd quartile: 42-58). A total of 58 (13.6%) participants reported experiencing difficulty accessing SCS. In a multivariable analysis, factors positively associated with difficulty accessing SCS included daily crystal methamphetamine use (Adjusted odds ratio [AOR] = 2.60; 95% confidence interval [CI] 1.28-5.30), active injection drug use (AOR = 4.06; 95% CI 1.38-11.90), recent non-fatal overdose (AOR = 2.45; 95% CI 1.24-4.85), and unstable housing (AOR = 2.14; 95% CI 1.08-4.23). Age was inversely associated with the outcome (AOR = 0.96; 95% CI 0.93-0.99) in multivariable analyses. The most commonly reported reasons for experiencing difficulty accessing SCS were: COVID-19-related site closure or shortened hours (42.9%) and having to wait too long to use a site (39.3%).

CONCLUSIONS

We found that people who use drugs with markers of structural vulnerability and drug-related risk were more likely to experience difficulty accessing SCS during the COVID-19 pandemic. These findings point to the need for strategies to support access to such services as part of pandemic response efforts.

Predictors of crystal methamphetamine use initiation or re-initiation among people receiving opioid agonist therapy: A prospective cohort study

BACKGROUND

In the context of the ongoing opioid crisis in the United States and Canada, opioid agonist therapy (OAT) is the first-line treatment for opioid use disorder. However, there is growing concern regarding the increasing methamphetamine use among those on OAT, as well as the impact of such use may have on OAT retention and outcomes. We sought to identify the predictors of crystal methamphetamine initiation or re-initiation among people on OAT, in order to facilitate the development of effective preventive strategies.

METHODS

We employed multivariable generalized estimating equations to identify the predictors of crystal methamphetamine use initiation or re-initiation among those who were on OAT within two prospective cohorts in Vancouver, Canada between 2005 and 2020.

RESULTS

Of the 1281 participants receiving OAT, the median age was 43 years, and 59.2 % were male at baseline. During study follow-up, 564 (44.0 %) initiated or re-initiated crystal methamphetamine use while receiving OAT. In a multivariable model, a higher crystal methamphetamine use initiation or re-initiation rate was positively associated with younger age, unstable housing, unprotected sex, history of crystal methamphetamine use, as well as recent cocaine, prescription opioid, and unregulated opioid use (all p < 0.05).

CONCLUSIONS

We identified high and increasing rates of crystal methamphetamine use initiation or re-initiation among our sample of people on OAT. Intervention strategies including housing program referral, sexual risk reduction, and integrated treatment approaches targeting polysubstance use are urgently needed to reduce the risks associated with methamphetamine use as well as the co-use of methamphetamine and opioids.

Virological suppression among gay, bisexual, and other men who have sex with men living with HIV in Vancouver, Canada: A longitudinal cohort study from 2012-2017

INTRODUCTION

In 2010, British Columbia (BC) implemented HIV Treatment as Prevention (TasP) as policy. We examined trends in virologic suppression and determinants of significant viremia among a prospective biobehavioural cohort of men who have sex with men (gbMSM) in Vancouver from 2012-2017.

METHODS

Respondent-driven sampling was used to recruit sexually active gbMSM (≥16 years) who completed biannual study visits with a computer-assisted self-interview and clinical CD4 and viral load (VL) testing. We linked participant data with the BC HIV Drug Treatment Program to obtain antiretroviral dispensing and VL data. We conducted a trend analysis of VL suppression using univariable generalized estimating equation (GEE) multi-level modelling and multivariable GEE to identify factors associated with episodes of VL ≥200 copies/mL.

RESULTS

Of 774 participants, 223 were living with HIV at baseline and 16 were diagnosed during follow-up (n = 239). We observed a significant trend towards reduced levels of unsuppressed VL (>200 copies/mL) from 22% (07/2012-12/2012) to 12% (07/2016-12/2016) (OR:0.87; 95%CI:0.83-0.91 for each 6-month period). Among those with at least one follow-up visit, (n = 178, median follow-up = 3.2 years, median age = 46.9 years), younger age (aOR:0.97; 95%CI:0.94-0.99, per year), ecstasy use (aOR:1.69; 95%CI:1.13-2.53), crystal methamphetamine use (aOR:1.71; 95%CI:1.18-2.48), seeking sex via websites (aOR:1.46; 95%CI:1.01-2.12), and lower HIV treatment optimism (aOR:0.94; 95%CI:0.90-0.97) were associated with episodes of elevated viremia.

CONCLUSIONS

During a period when TasP policy was actively promoted, we observed a significant trend towards reduced levels of unsuppressed VL. Continued efforts should promote HIV treatment optimism and engagement, especially among younger gbMSM and those who use ecstasy and crystal methamphetamine.

Amyloidosis-related echo features and mortality in patients with multiple myeloma

Background/Introduction

Patients with multiple myeloma (MM) are at increased risk of developing AL amyloidosis. It was determined by screening fat pad and bone marrow biopsy that 38% MM patients had amyloidosis at time of diagnosis and the majority were asymptomatic (1). However, whether amyloidosis-related echo features in MM affect survival remains unknown (1, 2).

Purpose

The goals of our study are to: 1) characterize prevalence of amyloidosis-related echo features in patients with multiple myeloma, 2) investigate whether decrease in longitudinal strain affect survival outcomes.

Methods

Patients diagnosed with MM between Jan 1, 2000 and Dec 31, 2017 at our institution were identified through Clinical Looking Glass. Those with echo within 1 year after myeloma diagnosis and left ventricular ejection fraction (LVEF) greater than 40% were included. Global longitudinal strain (GLS) and LVEF measurements were done using EchoGo (Ultromics, Oxford, UK). The average of GLS obtained from apical 4-chamber and apical 2-chamber views was used for analysis, with decreased GLS defined as absolute value less than 18%. Statistical analysis was conducted with STATA13, using Chi square test and Kruskal-Wallis for univariable analysis and Cox regression model for survival analysis.

Results

From a total cohort of 909 patients, 252 met inclusion criteria, of which 59 (23.4%) patients had decreased average GLS (see Table 1). Patients' mean age was 63±11 years, 44.8% were male and most were Black (42.7%) and the rest Hispanic (33.3%) and White (7.9%). Median follow up time was 4.25 years. The group with decreased GLS had lower percentage of females (22% vs 51.8%, p&lt;0.01), higher percentage of previous MI (11.9% vs 1.6%, p&lt;0.01) and more prior diagnosis of heart failure (20.3% vs 1.6%, p&lt;0.01).

Among patients with decreased GLS, five-year mortality rate was 63.3% compared to 46.0% in those with preserved GLS (p&lt;0.036). Median survival time was 3.9 years among those with reduced GLS and 4.3 years in those without (see Figure 1; p&lt;0.01). Reduced GLS correlated with decreased survival (HR 1.6, p=0.03) even after adjusting for demographic variables (age, gender, race), history of MI, history of CHF, Charlson comorbidity index, myeloma RISS stage, and LVEF (≥50% vs 40–50%).

Forty-seven (18.6%) patients had end diastolic inter-ventricular septum (IVSd) thickness ≥1.2cm. Median GLS in patients with increased IVSd thickness was 19% compared to 21% in those without (p=0.01). Nine patients had the apical sparing strain pattern for amyloidosis.

Total of 158 patients had bone marrow specimen stained with Congo-red with 7 (4.4%) testing positive. Median GLS was 19% in the group staining positive for Congo-red compared 21% in the group with negative stain (p=0.03).

Conclusions

Decrease in GLS on baseline echo correlates with increased mortality in patients with MM and may be due to subclinical cardiac amyloidosis.

Funding Acknowledgement

Type of funding sources: None.

[Progress of researches on albendazole for treatment of alveolar echinococcosis]

Alveolar echinococcosis, caused by Echinococcus multilocularis infection, is a highly deadly zoonotic parasitic disease. As a benzimidazole compound, albendazole has a strong and broad-spectrum anti-parasitic action. For alveolar echinococcosis patients that are unwilling to receive surgical treatment, lose the timing for surgery, or are intolerant to surgery due to poor physical status, administration of albendazole may delay disease progression. Recently, a large number of advances have been achieved in experimental studies on alveolar echinococcosis. In order to increase the understanding of the therapeutic efficacy of albendazole for alveolar echinococcosis, this review summarizes the advances in albendazole treatment for alveolar echinococcosis, so as to provide insights into the clinical treatment of alveolar echinococcosis with albendazole.

Observation of WWW Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WWW production and a measurement of its cross section using 139  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from WWW production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive WWW production cross section is measured to be 820±100 (stat)±80 (syst)  fb, approximately 2.6 standard deviations from the predicted cross section of 511±18  fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy.

Hosts as Gatekeepers for North American Gay and Bisexual Men's Private Group Sex Parties

Gay and bisexual men's (GBM) group sex parties are considered HIV risk environments due to their association with concurrent sexual partners, condomless anal sex, and polysubstance use. The possibility of group sex party hosts acting as gatekeepers to minimize risks has been suggested, but remains understudied. We analyzed qualitative data from 20 in-depth interviews with North American GBM who recently attended private group sex parties to determine if hosts' actions constitute harm reduction strategies. Results showed hosts acting as gatekeepers before parties by establishing and disseminating themes and rules, screening applicants, and selecting guests. During parties hosts enforced rules and rejected uninvited guests. By their actions, hosts established a more controlled environment compared to public sex-on-premises bathhouses, and facilitated boundary play, the paradoxical behavior of simultaneously desiring risk and safety, previously noted for GBM circuit parties. Results suggest initiating education programs focusing on private group sex party hosts as gatekeepers.