Needle and syringe sharing among people who have recently injected drugs in Australia: The ETHOS Engage Study.

INTRODUCTION: Understanding needle/syringe sharing is crucial for reducing hepatitis C virus (HCV) infection and reinfection. This study aimed to assess the prevalence and factors associated with needle/syringe sharing among people who inject drugs in Australia, including those previously receiving HCV treatment. METHODS: The ETHOS Engage study was an observational cohort study which collected self-reported survey data on demographic and drug use information from people who inject drugs attending drug treatment clinics and needle and syringe programs over two waves between May 2018 and June 2021. Logistic regression was used to identify factors associated with needle/syringe sharing. RESULTS: Overall, 1555/2395 people enrolled in ETHOS Engage (65%) injected drugs in the past month. Among these, 432 (28%) reported needle/syringe sharing in the past month and 276 (18%) reported receptive sharing. Factors associated with receptive sharing included younger age (adjusted odds ratio [aOR] 1.72; 95% confidence interval [CI] 1.28-2.30), recent incarceration (aOR 2.04; 95% CI 1.40-2.94), more frequent injecting (≥daily vs. less than weekly; aOR 2.59; 95% CI 1.75-3.84) and unstable housing (aOR 1.78; 95% CI 1.26-2.52). Among 560 participants with prior HCV treatment, 87 (16%) reported receptive sharing with younger age (aOR 2.42; 95% CI 1.45-4.05) and daily or greater injection frequency (aOR 2.51; 95% CI 1.31-4.83) associated with receptive sharing. DISCUSSION AND CONCLUSIONS: Needle/syringe sharing was common among this population accessing harm reduction services. This study identifies high-risk populations with needle/syringe sharing. Research is needed to optimise HCV treatment to ensure people with ongoing risk behaviours receive adequate harm reduction following treatment to prevent reinfection.

Oxycodone initiation in Australia (2014-2018): Sociodemographic factors and preceding health service use.

AIMS: Oxycodone is the most commonly prescribed strong opioid in Australia. This study describes health service antecedents and sociodemographic factors associated with oxycodone initiation. METHODS: Population-based new user cohort study linking medicine dispensings, hospitalizations, emergency department visits, medical services and cancer notifications from New South Wales (NSW) for 2014-2018. New users had no dispensings of any opioid in the preceding year. We analysed health service use in the 5 days preceding initiation and proportion of people on treatment over 1 year and fitted an area-based, multivariable initiation model with sociodemographic covariates. RESULTS: Oxycodone accounted for 30% of opioid initiations. Annually, 3% of the NSW population initiated oxycodone, and 5-6% were prevalent users; the new user cohort comprised 830 963 people. Discharge from hospital (39.3%), therapeutic procedures (21.4%) and emergency department visits (19.7%) were common; a hospital admission for injury (6.0%) or a past-year history of cancer (7.2%) were less common. At 1 year after initiation, 4.6% of people were using oxycodone. In the multivariable model, new use of oxycodone increased with age and was higher for people outside major cities, for example, an incidence rate ratio of 1.43 (95% confidence interval 1.36-1.51) for inner regional areas relative to major cities; there was no evidence of variation in rates of new use by social disadvantage. CONCLUSION: About half of new oxycodone use in NSW was preceded by a recent episode of hospital care or a therapeutic procedure. Higher rates of oxycodone initiation in rural and regional areas were not explained by sociodemographic factors.

Factors associated with hepatitis C testing, treatment, and current hepatitis C infection among men and women who inject drugs: The ETHOS engage study.

BACKGROUND: Evaluating gender-specific trends in hepatitis C virus (HCV) treatment uptake among men and women who inject drugs is crucial for ensuring equitable progress towards HCV elimination. This study aimed to quantify differences in testing, treatment, and current HCV infection between men and women who inject drugs. METHOD: ETHOS Engage is an observational cohort study of people who inject drugs attending drug treatment clinics and needle and syringe programs in Australia recruited from May 2018-September 2019 (wave 1) and November 2019-April 2021 (wave 2). Participants completed a questionnaire including self-reported HCV testing and treatment history and underwent point-of-care HCV RNA testing (Xpert® HCV Viral Load Fingerstick). Logistic regression was used to compare the factors associated with self-reported HCV testing and treatment and current HCV infection for men and women who inject drugs. RESULTS: Among 2,395 participants enrolled in ETHOS Engage, 66% (n = 1,591) were men, 33% (n = 786) women, and <1% (n = 18) did not identify as a man or woman. HCV testing history and current infection were similar among men and women. Among men or women ever eligible for HCV treatment (ever chronic HCV) (n = 1,242), women were less likely to report a history of HCV treatment compared to men (227/352, 64% vs. 631/890, 71%; p = 0.03). Among women, those aged <45 were less likely to report HCV testing (aOR: 0.57, 95%CI: 0.36, 0.90), treatment (aOR: 0.47, 95%CI: 0.29, 0.77), and more likely to have HCV infection (aOR: 1.48, 95%CI: 1.00, 2.20) CONCLUSION: Among women, those of childbearing age (<45) were less likely to report testing and treatment and were more likely to have current HCV infection. Women <45 years old should be a priority population for HCV care. Services that interface with these women should be optimised to enhance HCV testing and treatment.

High COVID-19 vaccine uptake following initial hesitancy among people in Australia who inject drugs.

BACKGROUND: Previous studies have reported high COVID-19 vaccine hesitancy among people who inject drugs. We aimed to examine COVID-19 vaccine coverage, motivations and barriers to vaccination, and factors associated with uptake among this population in Australia, 1.5 years after vaccine rollout commenced. METHODS: In June-July 2022, 868 people (66.0 % male, mean age 45.6 years) who regularly inject drugs and reside in an Australian capital city reported the number of COVID-19 vaccine doses they had received and their primary motivation (if vaccinated) or barrier (if unvaccinated) to receive the vaccine. We compared vaccine uptake to Australian population estimates and used logistic regression to identify factors associated with ≥ 2 dose and ≥ 3 dose uptake. RESULTS: Overall, 84.1 % (n = 730) had received at least one COVID-19 vaccine dose, 79.6 % (n = 691) had received ≥ 2 doses, and 46.1 % (n = 400) had received ≥ 3 doses. Participants were less likely to be vaccinated than the Australian general population (prevalence ratio: 0.82, 95 % confidence interval [CI]: 0.76-0.88). Key motivations to receive the vaccine were to protect oneself or others from COVID-19, while barriers pertained to vaccine or government distrust. Opioid agonist treatment (adjusted odds ratio [aOR]: 2.49, 95 % CI: 1.44-4.42), current seasonal influenza vaccine uptake (aOR: 6.76, 95 % CI: 3.18-16.75), and stable housing (aOR: 1.58, 95 % CI: 1.02-2.80) were associated with receipt of at least two vaccine doses. Participants aged ≥ 40 years (versus < 40 years; aOR: 1.66, 95 % CI: 1.10-2.53) or who reported a chronic health condition (aOR: 1.71, 95 % CI: 1.18-2.47) had higher odds of receiving at least three vaccine doses. CONCLUSION: We observed higher COVID-19 vaccine uptake than expected given previous studies of vaccine acceptability among people who inject drugs. However, it was lower than the general population. People who inject drugs and reside in unstable housing are a subpopulation that require support to increase vaccine uptake.

96-week retention in treatment with extended-release subcutaneous buprenorphine depot injections among people with opioid dependence: Extended follow-up after a single-arm trial.

BACKGROUND: The most recent formulation of buprenorphine treatment is extended-release depot injections (BUP-XR) that are administered subcutaneously by health care professionals. This study aimed to observe treatment outcomes of BUP-XR delivered in standard practice during a 96-week follow-up period in a community setting. METHODS: This study is an extension of the CoLAB study, a prospective single-arm, multicentre, open label trial (N=100, 7 sites in Australia) among people with opioid dependence who received monthly injections of BUP-XR to evaluate the retention in treatment. Participants were followed for 96 weeks, comprising 48 weeks of the CoLAB study followed by a 48-week extension. RESULTS: Of 100 participants at baseline, 47 were retained on BUP-XR at 96 weeks. The median time retained on monthly depot was 90 weeks. Heroin use (adjusted OR=0.19, P=0.012) in the month prior to baseline was associated with lower odds of retention on BUP-XR. Older age at first opioid use (adjusted OR= 1.08, P=0.009) and longer duration in OAT at baseline (adjusted OR= 1.12, P=0.001) were associated with increased retention. Prevalence of past four-weeks opioid use was estimated at 4% at 96 weeks of treatment (prevalence 0.04, 95%CI: 0.00-0.11) compared to 15% at baseline. Quality of life and medication treatment satisfaction improved over time for those retained in treatment. CONCLUSION: This is one of the few studies to describe long term (96 week) retention in treatment with BUP-XR in a community setting. It displayed retention rates with 47% of participants completing 96 weeks of treatment with BUP-XR. Patient reported outcomes suggest improvements in client wellbeing. FUNDING: Indivior.

Vaccination coverage among people who inject drugs: A systematic review.

BACKGROUND: People who inject drugs may be at excess risk of acquiring vaccine-preventable diseases and negative associated health outcomes, but experience barriers to vaccination. We aimed to determine vaccination coverage among people who inject drugs globally. METHODOLOGY: We conducted systematic searches of the peer-reviewed and grey literature, date limited from January 2008 to August 2023, focusing on diseases for which people who inject drugs are at elevated risk for and for which an adult vaccination dose is recommended (COVID-19, hepatitis A, hepatitis B, human papillomavirus, influenza, pneumococcal disease, tetanus). To summarise available data, we conducted a narrative synthesis. RESULTS: We included 78 studies/reports comprising 117 estimates of vaccination coverage across 36 countries. Most estimates were obtained from high income countries (80%, n=94). We located estimates for hepatitis B vaccination in 33 countries, which included 18 countries with data on serological evidence of vaccine-derived hepatitis B immunity (range: 6-53%) and 22 countries with self-report data for vaccine uptake (<1-96%). Data for other vaccines were scarcer: reported hepatitis A vaccination coverage ranged 3-89% (five countries), COVID-19 ranged 4-84% (five countries), while we located estimates from fewer than five countries for influenza, tetanus, pneumococcal disease, and human papillomavirus. CONCLUSION: Estimates were sparse but where available indicative of suboptimal vaccination coverage among people who inject drugs. Improving the consistency, timeliness, and geographic coverage of vaccine uptake data among this population is essential to inform efforts to increase uptake.

Health utility among people who regularly use opioids in Australia.

INTRODUCTION: Studies of health utilities among people who use opioids have mostly been based on in-treatment populations. We aim to report utility-based quality of life by participants' socio-demographic, drug and treatment characteristics, and to examine the determinants of health utility among people who use opioids regularly. METHODS: Cross-sectional study of participants who used opioids regularly, recruited across New South Wales, Victoria and Tasmania in 2018-2019. Differences in European Quality of Life (EQ-5D-5L) heath utility scores between socio-demographic and clinical subgroups were assessed using non-parametric Kruskal-Wallis test by rank. To address the unique distribution of EQ-5D-5L health utility scores in the current sample, a two-part model was applied to assess factors associated with health utility. RESULTS: Among 402 participants enrolled in the study, 385 (96%) completed the EQ-5D-5L questionnaire. The mean health utility of the total sample was 0.63 (SD 0.29). Participants who previously received opioid agonist treatment [OAT] (adj marginal effect (ME) -0.11; 95% confidence interval [CI] -0.20 to -0.02) and those currently in OAT (adj ME -0.13; 95% CI -0.22 to -0.06) reported lower health utility than those who had never received OAT. Participants who used both pharmaceutical opioids and benzodiazepines had lower health utility compared to no pharmaceutical opioids and no benzodiazepines use (adj ME -0.17; 95% CI -0.28 to -0.07). DISCUSSION AND CONCLUSIONS: Findings provide important health utility data for economic evaluations, useful for guiding allocation of resources for treatment strategies among people who use opioids. Lower health utilities among those using benzodiazepines and pharmaceutical opioids suggests interventions targeting these subgroups may be beneficial.

Age-Related Risk of Serious Fall Events and Opioid Analgesic Use.

Importance: Opioid analgesics may be associated with increased risk of falls, particularly among older adults. Objective: To quantify the age-related risk of serious fall events among adults prescribed opioids by opioid exposure, time from initiation, and daily dose. Design, Setting, and Participants: This population-based cohort study conducted in New South Wales, Australia, used data linking national pharmaceutical claims to national and state datasets, including information on sociodemographic characteristics, clinical characteristics, medicines use, health services utilization, and mortality (POPPY II study). It included adults (18 years or older) who initiated prescription opioid treatment, which was defined as no prior dispensing during the preceding 365 days, between January 1, 2005, and December 31, 2018. Data were analyzed from February to June 2023. Exposure: Time-dependent periods of opioid exposure were evaluated from dispensing records. Main Outcome and Measures: Serious fall events identified from emergency department, hospitalization, and mortality records. Negative binomial models were used to assess associations between time-dependent opioid exposure (overall, by time from initiation, and by dose), age, and risk of fall events. Models were adjusted for known fall risk factors, including other fall risk-increasing drugs, frailty risk, and prior serious fall events. Results: The cohort comprised 3 212 369 individuals who initiated prescription opioid treatment (1 702 332 women [53%]; median [IQR] age at initiation, 49 [32-65] years). Overall, 506 573 serious fall events were identified, including 5210 fatal falls. During exposure to opioids, the risk of serious fall events was elevated among all age groups; compared with the group aged 18 to 44 years, this risk was highest among those 85 years or older (adjusted incident rate ratio, 6.35; 95% CI, 6.20-6.51). Across all age groups, the first 28 days following opioid initiation was a time of increased serious fall risk; this risk increased with age. Among individuals aged 18 to 84 years, associations were identified between higher daily opioid doses and serious fall events. Conclusions and Relevance: The results of this cohort study suggest that prescription opioids were associated with increased risk of serious fall events among adults of all ages, with individuals 85 years or older at greatest risk. These risks should be considered when prescribing opioids, particularly for individuals with preexisting risk factors or when opioids are prescribed at higher doses. Targeted falls prevention efforts may be most effective within the first month following opioid initiation.

Direct-acting antiviral therapies for hepatitis C infection: global registration, reimbursement, and restrictions.

Direct-acting antivirals (DAAs) for hepatitis C virus (HCV) infection have delivered high response rates (>95%) and simplified the management of HCV treatment, permitting non-specialists to manage patients without advanced liver disease. We collected and reviewed global data on the registration and reimbursement (government subsidised) of HCV therapies, including restrictions on reimbursement. Primary data collection occurred between Nov 15, 2021, and July 24, 2023, through the assistance of a global network of 166 HCV experts. We retrieved data for 160 (77%) of 209 countries and juristrictions. By mid-2023, 145 (91%) countries had registered at least one of the following DAA therapies: sofosbuvir-velpatasvir, sofosbuvir-velpatasvir-voxilaprevir, glecaprevir-pibrentasvir, sofosbuvir-daclatasvir, or sofosbuvir. 109 (68%) countries reimbursed at least one DAA therapy. Among 102 low-income and middle-income countries (LMICs), 89 (87%) had registered at least one HCV DAA therapy and 53 (52%) reimbursed at least one DAA therapy. Among all countries with DAA therapy reimbursement (n=109), 66 (61%) required specialist prescribing, eight (7%) had retreatment restrictions, seven (6%) had an illicit drug use restriction, five (5%) had an alcohol use restriction, and three (3%) had liver disease restrictions. Global access to DAA reimbursement remains uneven, with LMICs having comparatively low reimbursement compared with high-income countries. To meet WHO goals for HCV elimination, efforts should be made to assist countries, particularly LMICs, to increase access to DAA reimbursement and remove reimbursement restrictions-especially prescriber-type restrictions-to ensure universal access.

Trends in use of medicines for opioid agonist treatment in Australia, 2013-2022.

BACKGROUND: There are limited longitudinal data on national patterns of opioid agonist treatment (OAT). This study describes 10-year trends in the sales of OAT medicines in Australia. METHODS: A descriptive and time-series analysis of methadone, sublingual (SL) buprenorphine (+/-naloxone), and long-acting injectable (LAI) buprenorphine sold in Australia between 2013 and 2022 was performed. Total units sold were converted into an estimate of the number of clients that could be treated over a 28-day period with that amount of medicine ('client-months'). RESULTS: Between January 2013 and December 2022, the estimated number of client-months on: any OAT increased by 50 % to 53,501, methadone decreased (-8.5%), SL buprenorphine increased (+78%), and LAI buprenorphine increased substantially after September 2019. In January 2013, 78 % of OAT client-months received methadone. By December 2022, 48 % received methadone, 26 % SL buprenorphine, and 26 % LAI buprenorphine. Between 2013 to 2022, OAT client-months per capita were highest in the state of New South Wales. Over the study period, greater increases in OAT were observed in very remote areas (88%) compared to major cities (53%). The number of client-months in non-community pharmacy settings remained stable from 2013 to 2019/20, before increasing markedly. The introduction of LAI buprenorphine was associated with an immediate, sustained increase of 1,636 OAT client-months, and further increases of 190 OAT client-months each month. CONCLUSION: Patterns of OAT have shifted over the last 10-years with buprenorphine (SL/LAI) now the most common OAT used in Australia. The introduction of LAI buprenorphine has expanded OAT access, particularly in non-community pharmacy settings, and in remote areas.

Prescription opioid use among people with opioid dependence and concurrent benzodiazepine and gabapentinoid exposure: An analysis of overdose and all-cause mortality.

BACKGROUND: Studies investigating mortality risk associated with use of opioid analgesics, benzodiazepines, gabapentinoids, and opioid agonist treatment (OAT) among people with opioid dependence (PWOD) are lacking. This study addresses this gap using a cohort of 37,994 PWOD initiating opioid analgesics between July 2003 and July 2018 in New South Wales, Australia. METHODS: Linked administrative records provided data on dispensings, sociodemographics, clinical characteristics, OAT, and mortality. Cox proportional hazards models assessed associations between time-varying measures of individual and concurrent medicine use and OAT with all-cause mortality, accidental opioid overdose, non-drug induced accidents, and non-drug-induced suicide. Opioid analgesic dose effects, expressed as oral morphine equivalents (OMEs) per day, were also examined. OUTCOMES: During the study period, 3167 individuals died. Compared with no use, all medicines of interest were associated with increased accidental opioid overdose risk; hazard ratios (HR) ranged from 1.33 (95 % CI: 1.05-1.68) for opioid analgesic use to 6.10 (95 % CI: 4.11-9.06) for opioid analgesic, benzodiazepine and gabapentinoid use. Benzodiazepine use was associated with increased non-drug-induced accidents and non-drug-induced suicides. For all-cause mortality, all combinations of benzodiazepines and gabapentinoids with opioid analgesics were associated with increased risk (aHRs ranged from 1.35 to 2.73). For most medicines/medicine combinations, all-cause mortality risk was reduced when in OAT compared to out of OAT. Higher opioid analgesic doses were associated with increased all-cause mortality (e.g., 90-199 mg vs 1-49 mg OME per day: HR 1.90 [95 % CI: 1.52-2.40]). INTERPRETATION: The increased mortality risk associated with benzodiazepines and gabapentinoids among PWOD appear to be reduced when engaged in OAT. A greater focus on encouraging OAT engagement, providing overdose prevention education, and access and coverage of overdose antidotes is necessary to minimise the unintended consequences of medicines use in this population.

Global, regional, and country-level coverage of testing and treatment for HIV and hepatitis C infection among people who inject drugs: a systematic review.

BACKGROUND: People who inject drugs are disproportionately affected by HIV and hepatitis C virus (HCV) infections, while there is little global data on HIV and HCV testing and treatment coverage of this population. We conducted a systematic review to evaluate country-level, regional, and global coverage of HIV and HCV testing and treatment among people who inject drugs. METHODS: We did a systematic review, and searched bibliographic databases (MEDLINE, Embase, and PsycINFO) and grey literature for studies published between Jan 1, 2017, and April 30, 2022, that evaluated the proportion of people who inject drugs who received testing or treatment for HIV or HCV. For each country, we estimated the proportion of people who inject drugs tested for HIV antibodies in the past 12 months (recent), people who inject drugs ever tested for HCV antibodies and HCV RNA, people who inject drugs with HIV currently receiving antiretroviral therapy, and people who inject drugs with HCV ever receiving HCV antiviral treatment. Regional and global estimates, weighted by the population size of people who inject drugs, were generated where sufficient data were available. This study is registered with PROSPERO (CRD42020173974). FINDINGS: 512 documents reported data eligible for analyses, including 337 peer-reviewed articles, 27 conference abstracts or presentations, and 148 documents from grey literature or supplementary searches. Data of recent HIV antibody testing were available for 67 countries and ever having had HCV antibody testing were available for 49 countries. Globally, an estimated 48·8% of people who inject drugs were recently tested for HIV antibodies (95% uncertainty interval [UI] 43·3-54·2%; range 0·9-86·0%), and 47·1% had ever been tested for HCV antibodies (95% UI 43·4-51·0%; range 0·0-93·3%). HCV RNA testing data were available from three countries. Coverage of HIV antibody testing was high (>75%) in four countries and for HCV antibody testing in 15 countries. The estimated uptake of current HIV treatment (18 countries) ranged from 2·6% to 81·9%, and the estimated uptake of ever having HCV treatment (23 countries) ranged from 1·8% to 88·6% across countries. Uptake of HIV treatment was high in two countries, and of HCV treatment in one country. INTERPRETATION: HIV and HCV testing and treatment uptake among people who inject drugs was highly variable, and suboptimal in most countries. Strategies to improve access to HIV and HCV care among people who inject drugs and the availability of public health surveillance are urgently required. FUNDING: Australian National Health and Medical Research Council and UK National Institute for Health and Care Research Health Protection Research Unit in Behavioural Science and Evaluation.

Clinical Observation, Management and Function Of low back pain Relief Therapies (COMFORT): A cluster randomised controlled trial protocol.

INTRODUCTION: Low back pain (LBP) is commonly treated with opioid analgesics despite evidence that these medicines provide minimal or no benefit for LBP and have an established profile of harms. International guidelines discourage or urge caution with the use of opioids for back pain; however, doctors and patients lack practical strategies to help them implement the guidelines. This trial will evaluate a multifaceted intervention to support general practitioners (GPs) and their patients with LBP implement the recommendations in the latest opioid prescribing guidelines. METHODS AND ANALYSIS: This is a cluster randomised controlled trial that will evaluate the effect of educational outreach visits to GPs promoting opioid stewardship alongside non-pharmacological interventions including heat wrap and patient education about the possible harms and benefits of opioids, on GP prescribing of opioids medicines dispensed. At least 40 general practices will be randomised in a 1:1 ratio to either the intervention or control (no outreach visits; GP provides usual care). A total of 410 patient-participants (205 in each arm) who have been prescribed an opioid for LBP will be enrolled via participating general practices. Follow-up of patient-participants will occur over a 1-year period. The primary outcome will be the cumulative dose of opioid dispensed that was prescribed by study GPs over 1 year from the enrolment visit (in morphine milligram equivalent dose). Secondary outcomes include prescription of opioid medicines, benzodiazepines, gabapentinoids, non-steroidal anti-inflammatory drugs by study GPs or any GP, health services utilisation and patient-reported outcomes such as pain, quality of life and adverse events. Analysis will be by intention to treat, with a health economics analysis also planned. ETHICS AND DISSEMINATION: The trial received ethics approval from The University of Sydney Human Research Ethics Committee (2022/511). The results will be disseminated via publications in journals, media and conference presentations. TRIAL REGISTRATION NUMBER: ACTRN12622001505796.

Effect of incarceration and opioid agonist treatment transitions on risk of hospitalisation with injection drug use-associated bacterial infections: A self-controlled case series in New South Wales, Australia.

BACKGROUND: Transitional times in opioid use, such as release from prison and discontinuation of opioid agonist treatment (OAT), are associated with health harms due to changing drug consumption practices and limited access to health and social supports. Using a self-controlled (within-person) study design, we aimed to understand if these transitions increase risks of injection drug use-associated bacterial infections. METHODS: We performed a self-controlled case series among a cohort of people with opioid use disorder (who had all previously accessed OAT) in New South Wales, Australia, 2001-2018. The outcome was hospitalisation with injecting-related bacterial infections. We divided participants' observed days into time windows related to incarceration and OAT receipt. We compared hospitalization rates during focal (exposure) windows and referent (control) windows (i.e., 5-52 weeks continuously not incarcerated or continuously receiving OAT). We estimated adjusted incidence rate ratios (aIRR) using conditional logistic regression, adjusted for time-varying confounders. RESULTS: There were 7590 participants who experienced hospitalisation with injecting-related bacterial infections (35% female; median age 38 years; 78% hospitalised with skin and soft-tissue infections). Risk for injecting-related bacterial infections was elevated for two weeks following release from prison (aIRR 1.45; 95%CI 1.22-1.72). Risk was increased during two weeks before (aIRR 1.89; 95%CI 1.59-2.25) and after (aIRR 1.91; 95%CI 1.54-2.36) discontinuation of OAT, and during two weeks before (aIRR 3.63; 95%CI 3.13-4.22) and after (aIRR 2.52; 95%CI 2.09-3.04) OAT initiation. CONCLUSION: Risk of injecting-related bacterial infections varies greatly within-individuals over time. Risk is raised immediately after prison release, and around initiation and discontinuation of OAT. Social contextual factors likely contribute to excess risks at transitions in incarceration and OAT exposure.

Age of onset and cumulative risk of mental disorders: a cross-national analysis of population surveys from 29 countries.

BACKGROUND: Information on the frequency and timing of mental disorder onsets across the lifespan is of fundamental importance for public health planning. Broad, cross-national estimates of this information from coordinated general population surveys were last updated in 2007. We aimed to provide updated and improved estimates of age-of-onset distributions, lifetime prevalence, and morbid risk. METHODS: In this cross-national analysis, we analysed data from respondents aged 18 years or older to the World Mental Health surveys, a coordinated series of cross-sectional, face-to-face community epidemiological surveys administered between 2001 and 2022. In the surveys, the WHO Composite International Diagnostic Interview, a fully structured psychiatric diagnostic interview, was used to assess age of onset, lifetime prevalence, and morbid risk of 13 DSM-IV mental disorders until age 75 years across surveys by sex. We did not assess ethnicity. The surveys were geographically clustered and weighted to adjust for selection probability, and standard errors of incidence rates and cumulative incidence curves were calculated using the jackknife repeated replications simulation method, taking weighting and geographical clustering of data into account. FINDINGS: We included 156 331 respondents from 32 surveys in 29 countries, including 12 low-income and middle-income countries and 17 high-income countries, and including 85 308 (54·5%) female respondents and 71 023 (45·4%) male respondents. The lifetime prevalence of any mental disorder was 28·6% (95% CI 27·9-29·2) for male respondents and 29·8% (29·2-30·3) for female respondents. Morbid risk of any mental disorder by age 75 years was 46·4% (44·9-47·8) for male respondents and 53·1% (51·9-54·3) for female respondents. Conditional probabilities of first onset peaked at approximately age 15 years, with a median age of onset of 19 years (IQR 14-32) for male respondents and 20 years (12-36) for female respondents. The two most prevalent disorders were alcohol use disorder and major depressive disorder for male respondents and major depressive disorder and specific phobia for female respondents. INTERPRETATION: By age 75 years, approximately half the population can expect to develop one or more of the 13 mental disorders considered in this Article. These disorders typically first emerge in childhood, adolescence, or young adulthood. Services should have the capacity to detect and treat common mental disorders promptly and to optimise care that suits people at these crucial parts of the life course. FUNDING: None.

Five-Year Trajectories of Prescription Opioid Use.

Importance: There are known risks of using opioids for extended periods. However, less is known about the long-term trajectories of opioid use following initiation. Objective: To identify 5-year trajectories of prescription opioid use, and to examine the characteristics of each trajectory group. Design, Setting, and Participants: This population-based cohort study conducted in New South Wales, Australia, linked national pharmaceutical claims data to 10 national and state data sets to determine sociodemographic characteristics, clinical characteristics, drug use, and health services use. The cohort included adult residents (aged ≥18 years) of New South Wales who initiated a prescription opioid between July 1, 2003, and December 31, 2018. Statistical analyses were conducted from February to September 2022. Exposure: Dispensing of a prescription opioid, with no evidence of opioid dispensing in the preceding 365 days, identified from pharmaceutical claims data. Main Outcomes and Measures: The main outcome was the trajectories of monthly opioid use over 60 months from opioid initiation. Group-based trajectory modeling was used to classify these trajectories. Linked health care data sets were used to examine characteristics of individuals in different trajectory groups. Results: Among 3 474 490 individuals who initiated a prescription opioid (1 831 230 females [52.7%]; mean [SD] age, 49.7 [19.3] years), 5 trajectories of long-term opioid use were identified: very low use (75.4%), low use (16.6%), moderate decreasing to low use (2.6%), low increasing to moderate use (2.6%), and sustained use (2.8%). Compared with individuals in the very low use trajectory group, those in the sustained use trajectory group were older (age ≥65 years: 22.0% vs 58.4%); had more comorbidities, including cancer (4.1% vs 22.2%); had increased health services contact, including hospital admissions (36.9% vs 51.6%); had higher use of psychotropic (16.4% vs 42.4%) and other analgesic drugs (22.9% vs 47.3%) prior to opioid initiation, and were initiated on stronger opioids (20.0% vs 50.2%). Conclusions and relevance: Results of this cohort study suggest that most individuals commencing treatment with prescription opioids had relatively low and time-limited exposure to opioids over a 5-year period. The small proportion of individuals with sustained or increasing use was older with more comorbidities and use of psychotropic and other analgesic drugs, likely reflecting a higher prevalence of pain and treatment needs in these individuals.

Evaluating the prevalence of current hepatitis C infection and treatment among Aboriginal and Torres Strait Islander peoples who inject drugs in Australia: The ETHOS engage study.

INTRODUCTION: Evaluating progress towards hepatitis C virus (HCV) elimination among Aboriginal and Torres Strait Islander peoples is critical given the disproportionate burden of infection. We examined factors associated with current HCV infection and self-reported treatment among Aboriginal and Torres Strait Islander (hereafter referred to as Aboriginal peoples) and non-Aboriginal peoples who inject drugs (PWID) in Australia. METHODS: ETHOS Engage is an observational cohort study of PWID attending drug treatment and needle and syringe programs in Australia. Participants underwent point-of-care HCV RNA testing (Xpert HCV RNA Viral Load Fingerstick) and completed a questionnaire including self-reported history of HCV treatment. RESULTS: Between May 2018 and June 2021, 2395 participants were enrolled and 555 (23%) identified as Aboriginal (median age 42 years, 58% were men, 63% injected drugs in last month, 76% ever incarcerated). HCV RNA prevalence was 23% among Aboriginal PWID (24% in 2018-2019 and 21% in 2019-2021; p = 0.44), and 21% among non-Aboriginal PWID (24% in 2018-2019 and 16% in 2019-2021; p < 0.001). Self-reported HCV treatment was 65% among Aboriginal PWID (63% in 2018-2019 and 69% in 2019-2021; p = 0.30), and 70% among non-Aboriginal PWID (67% in 2018-2019 and 75% in 2019-2021; p < 0.001). Among Aboriginal PWID, current HCV infection was associated with recently injecting drugs and receiving opioid agonist treatment, and self-reported HCV treatment was negatively associated with younger age, homelessness and recently injecting drugs. DISCUSSION AND CONCLUSIONS: Equitable access to HCV care and prevention is needed to ensure Australia meets its elimination targets among Aboriginal PWID.

Prevalence of opioid dependence in New South Wales, Australia, 2014-16: Indirect estimation from multiple data sources using a Bayesian approach.

AIMS: To estimate the prevalence of, and number of unobserved people with opioid dependence by sex and age group in New South Wales (NSW), Australia. DESIGN: We applied a Bayesian statistical modelling approach to opioid agonist treatment records linked to adverse event rate data. We estimated prevalence from three types of adverse event separately: opioid mortality, opioid-poisoning hospitalizations and opioid-related charges. We extended the model and produced prevalence estimates from a 'multi-source' model based on all three types of adverse event data. SETTING, PARTICIPANTS AND MEASUREMENTS: This study was conducted in NSW, Australia, 2014-16 using data from the Opioid Agonist Treatment and Safety (OATS) study, which included all people who had received treatment for opioid dependence in NSW. Aggregate data were obtained on numbers of adverse events in NSW. Rates of each adverse event type within the OATS cohort were modelled. Population data were provided by State and Commonwealth agencies. FINDINGS: Prevalence of opioid dependence among those aged 15-64 years in 2016 was estimated to be 0.96% (95% credible interval [CrI] = 0.82%, 1.12%) from the mortality model, 0.75% (95% CrI = 0.70%, 0.83%) from hospitalizations, 0.95% (95% CrI = 0.90%, 0.99%) from charges and 0.92% (95% CrI = 0.88%, 0.96%) from the multi-source model. Of the estimated 46 460 (95% CrI = 44 680, 48 410) people with opioid dependence in 2016 from the multi-source model, approximately one-third (16 750, 95% CrI = 14 960, 18 690) had no record of opioid agonist treatment within the last 4 years. From the multi-source model, prevalence in 2016 was estimated to be 1.24% (95% CrI = 1.18%, 1.31%) in men aged 15-44, 1.22% (95% CrI = 1.14%, 1.31%) in men 45-64, 0.63% (95% CrI = 0.59%, 0.68%) in women aged 15-44 and 0.56% (95% CrI = 0.50%, 0.63%) in women aged 45-64. CONCLUSIONS: A Bayesian statistical approach to estimate prevalence from multiple adverse event types simultaneously calculates that the estimated prevalence of opioid dependence in NSW, Australia in 2016 was 0.92%, higher than previous estimates.

Methamphetamine exposure and depression-A systematic review and meta-analysis.

ISSUES: Methamphetamine use is a public health concern that has been associated with comorbid mental health problems. We aim to better understand the relationship between methamphetamine use and depression by: (i) systematically reviewing and meta-analysing the risks of depression by methamphetamine use; and (ii) investigating the risk of unmeasured confounding. APPROACH: A systematic review and meta-analysis were conducted following PRISMA guidelines. EMBASE, PsycINFO and PubMed were searched to identify human studies reporting on the association between methamphetamine or amphetamine use and depressive outcomes. The data were summarised narratively and meta-analysed, stratified by cross-sectional and longitudinal estimates. Unmeasured confounding was assessed by E-values analyses. KEY FINDINGS: From the 6606 studies that came up from the search, 14 eligible studies were included in the narrative review and had data for meta-analysis. A significant association was found between any use of methamphetamine and any depression outcomes in cross-sectional (odds ratio [OR] = 1.66 [95% confidence interval [CI] 1.34, 2.05]) and longitudinal estimates (OR = 1.18 [95% CI 1.08, 1.28]). People with a methamphetamine use disorder had significantly higher odds of depression than those without (OR = 2.80 [95% CI 1.40, 5.90]). The E-values ranged from 1.28 to 6.30 for cross-sectional studies and from 2.37 to 3.21 for longitudinal studies. CONCLUSION: Based on limited data, people who used methamphetamine have higher odds of depression than people who do not. There were mostly a low to moderate risk of unmeasured confounding in the longitudinal study results. Future longitudinal studies conducted using causal framework methods are warranted.

All-cause and cause-specific mortality in individuals with an alcohol-related emergency or hospital inpatient presentation: A retrospective data linkage cohort study.

BACKGROUND AND AIMS: Alcohol consumption is a leading risk factor for premature mortality globally, but there are limited studies of broader cohorts of people presenting with alcohol-related problems outside of alcohol treatment services. We used linked health administrative data to estimate all-cause and cause-specific mortality among individuals who had an alcohol-related hospital inpatient or emergency department presentation. DESIGN: Observational study using data from the Data linkage Alcohol Cohort Study (DACS), a state-wide retrospective cohort of individuals with an alcohol-related hospital inpatient or emergency department presentation. SETTING: Hospital inpatient or emergency department presentation in New South Wales, Australia, between 2005 and 2014. PARTICIPANTS: Participants comprised 188 770 individuals aged 12 and above, 66% males, median age 39 years at index presentation. MEASUREMENTS: All-cause mortality was estimated up to 2015 and cause-specific mortality (by those attributable to alcohol and by specific cause of death groups) up to 2013 due to data availability. Age-specific and age-sex-specific crude mortality rates (CMRs) were estimated, and standardized mortality ratios (SMRs) were calculated using sex and age-specific deaths rates from the NSW population. FINDINGS: There were 188 770 individuals in the cohort (1 079 249 person-years of observation); 27 855 deaths were recorded (14.8% of the cohort), with a CMR of 25.8 [95% confidence interval (CI) = 25.5, 26.1] per 1000 person-years and SMR of 6.2 (95% CI = 5.4, 7.2). Mortality in the cohort was consistently higher than the general population in all adult age groups and in both sexes. The greatest excess mortality was from mental and behavioural disorders due to alcohol use (SMR = 46.7, 95% CI = 41.4, 52.7), liver cirrhosis (SMR = 39.0, 95% CI = 35.5, 42.9), viral hepatitis (SMR = 29.4, 95% CI = 24.6, 35.2), pancreatic diseases (SMR = 23.8, 95% CI = 17.9, 31.5) and liver cancer (SMR = 18.3, 95% CI = 14.8, 22.5). There were distinct differences between the sexes in causes of excess mortality (all causes fully attributable to alcohol female versus male risk ratio = 2.5 (95% CI = 2.0, 3.1). CONCLUSIONS: In New South Wales, Australia, people who came in contact with an emergency department or hospital for an alcohol-related presentation between 2005 and 2014 were at higher risk of mortality than the general New South Wales population during the same period.