Long-term prescribed opioid use after hospitalization or emergency department presentation among opioid naïve adults (2014-2020)-A population-based descriptive cohort study.

AIMS: The aim of this work is to describe opioid initiation and long-term use after emergency department (ED) visits or hospitalizations in New South Wales, Australia, by patient, admission and clinical characteristics. METHODS: This is a population-based cohort study, including all hospitalizations and ED visits between 2014 and 2020, linked to medicine dispensings, deaths and cancer registrations (Medicines Intelligence Data Platform), among adults with no opioid dispensings in the previous year. Outcome measures were opioid initiations (dispensed within 7 days of discharge) and long-term use (90 days of continuous exposure, 90-270 days after initiation). RESULTS: The cohort included 16 153 096 admissions by 4.2 million opioid-naïve adults; 39.0% were ED presentations without hospital admission, 16.8% hospital admissions via ED and 44.2% direct hospital admissions. Opioids were initiated post-discharge for 6.2% of ED, 8.3% of hospital via ED and 10.0% of direct hospital admissions; of these 1.0%, 2.5% and 0.5% progressed to long-term opioid use, respectively. Initiation was lowest in obstetric admissions without surgery (1.0%), and highest among trauma admissions (25.4%), obstetric admissions with surgical intervention (19.8%) and non-trauma surgical admissions (12.0%). Long-term use was highest among medical admissions via ED (3.5%), trauma admissions (2.3%) and ED alone (1.0%). From 2014 to 2020, overall opioid initiations decreased 16% from 8.7% to 7.2%, and long-term opioid use decreased 33% from 1.3% to 0.8%. CONCLUSIONS: Both opioid initiation and long-term use decreased over time; however, the higher rates of long-term use following trauma, and medical admissions via ED, warrant further surveillance. Strategies supporting appropriate prescribing and access to multidisciplinary pain services will facilitate best practice care.

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.

The Medicines Intelligence Data Platform: A Population-Based Data Resource From New South Wales, Australia.

BACKGROUND: The Medicines Intelligence (MedIntel) Data Platform is an anonymised linked data resource designed to generate real-world evidence on prescribed medicine use, effectiveness, safety, costs and cost-effectiveness in Australia. RESULTS: The platform comprises Medicare-eligible people who are ≥18 years and residing in New South Wales (NSW), Australia, any time during 2005-2020, with linked administrative data on dispensed prescription medicines (Pharmaceutical Benefits Scheme), health service use (Medicare Benefits Schedule), emergency department visits (NSW Emergency Department Data Collection), hospitalisations (NSW Admitted Patient Data Collection) plus death (National Death Index) and cancer registrations (NSW Cancer Registry). Data are currently available to 2022, with approval to update the cohort and data collections annually. The platform includes 7.4 million unique people across all years, covering 36.9% of the Australian adult population; the overall population increased from 4.8 M in 2005 to 6.0 M in 2020. As of 1 January 2019 (the last pre-pandemic year), the cohort had a mean age of 48.7 years (51.1% female), with most people (4.4 M, 74.7%) residing in a major city. In 2019, 4.4 M people (73.3%) were dispensed a medicine, 1.2 M (20.5%) were hospitalised, 5.3 M (89.4%) had a GP or specialist appointment, and 54 003 people died. Anti-infectives were the most prevalent medicines dispensed to the cohort in 2019 (43.1%), followed by nervous system (32.2%) and cardiovascular system medicines (30.2%). CONCLUSION: The MedIntel Data Platform creates opportunities for national and international research collaborations and enables us to address contemporary clinically- and policy-relevant research questions about quality use of medicines and health outcomes in Australia and globally.

Age, period, and cohort trends of substance poisoning, alcohol-related disease, and suicide deaths in Australia, 1980-2019.

PURPOSE: Deaths due to substance poisoning, alcohol-related disease, and suicide pose a critical public health issue, and have been categorized as "deaths of despair" in the US. Whether these deaths represent a distinct phenomenon requires exploration, particularly in other countries. METHODS: This retrospective observational study examines age-period-cohort trends of (combined and cause-specific) substance poisoning, alcohol-related disease, and suicide deaths among Australians aged ≥15-years that occurred between 1980 and 2019 and compares trends between males and females. RESULTS: Combined mortality rates were initially (1980-1999) relatively stable, reflecting a reduction in alcohol-related disease deaths offset by an increase in substance poisoning deaths. A decline (2000-2006) and subsequent increase (2007-2019) in combined rates were primarily attributable to corresponding changes in both substance poisoning and suicide deaths among males. Distinct age-period-cohort trends were observed between cause of death sub-types, with net drifts: increasing for male (net drift [95% CI]: 3.33 [2.84, 3.83]) and female (2.58 [2.18, 2.98]) substance poisoning deaths; decreasing among male alcohol-related disease (- 1.46 [- 1.75, - 1.16]) and suicide deaths (- 0.52[- 0.69, - 0.36]); and remaining relatively stable for female alcohol-related disease (- 0.28 [- 0.66, 0.09]) and suicide deaths (- 0.25 [- 0.52, 0.01]). CONCLUSIONS: Although combined age-specific trends were relatively stable over the study period, different and distinct patterns were observed within cause-specific deaths, challenging the notion that these causes of death represent a distinct epidemiological phenomenon. These data indicate a critical need to review the appropriateness of guidance for clinical practice, prevention strategies, and policy initiatives aimed at preventing future deaths.

Association between Mental Disorders and Subsequent Medical Conditions.

BACKGROUND: Persons with mental disorders are at a higher risk than the general population for the subsequent development of certain medical conditions. METHODS: We used a population-based cohort from Danish national registries that included data on more than 5.9 million persons born in Denmark from 1900 through 2015 and followed them from 2000 through 2016, for a total of 83.9 million person-years. We assessed 10 broad types of mental disorders and 9 broad categories of medical conditions (which encompassed 31 specific conditions). We used Cox regression models to calculate overall hazard ratios and time-dependent hazard ratios for pairs of mental disorders and medical conditions, after adjustment for age, sex, calendar time, and previous mental disorders. Absolute risks were estimated with the use of competing-risks survival analyses. RESULTS: A total of 698,874 of 5,940,299 persons (11.8%) were identified as having a mental disorder. The median age of the total population was 32.1 years at entry into the cohort and 48.7 years at the time of the last follow-up. Persons with a mental disorder had a higher risk than those without such disorders with respect to 76 of 90 pairs of mental disorders and medical conditions. The median hazard ratio for an association between a mental disorder and a medical condition was 1.37. The lowest hazard ratio was 0.82 for organic mental disorders and the broad category of cancer (95% confidence interval [CI], 0.80 to 0.84), and the highest was 3.62 for eating disorders and urogenital conditions (95% CI, 3.11 to 4.22). Several specific pairs showed a reduced risk (e.g., schizophrenia and musculoskeletal conditions). Risks varied according to the time since the diagnosis of a mental disorder. The absolute risk of a medical condition within 15 years after a mental disorder was diagnosed varied from 0.6% for a urogenital condition among persons with a developmental disorder to 54.1% for a circulatory disorder among those with an organic mental disorder. CONCLUSIONS: Most mental disorders were associated with an increased risk of a subsequent medical condition; hazard ratios ranged from 0.82 to 3.62 and varied according to the time since the diagnosis of the mental disorder. (Funded by the Danish National Research Foundation and others; COMO-GMC ClinicalTrials.gov number, NCT03847753.).

COVID-19 Testing in a Weekly Cohort Study of Gay and Bisexual Men: The Impact of Health-Seeking Behaviors and Social Connection.

Gay, bisexual, and other men who have sex with men (GBM) have developed community norms for regular HIV/STI testing. We investigated factors associated with self-reported COVID-19 testing in response to reported COVID-19 cases and public health restrictions. Participants responded to weekly cohort surveys between 10th May 2021 and 27th September 2021. We used the Andersen-Gill extensions to the Cox proportional hazards model for multivariable survival data to predict factors influencing COVID-19 testing. Mean age of the 942 study participants was 45.6 years (SD: 13.9). In multivariable analysis, GBM were more likely to report testing during periods of high COVID-19 caseload in their state of residence; if they were younger; university educated; close contact of someone with COVID-19; or reported coping with COVID-19 poorly. COVID-19 testing was higher among men who: were more socially engaged with other GBM; had a higher proportion of friends willing to vaccinate against COVID-19; and were willing to contact sexual partners for contact tracing. Social connection with other gay men was associated with COVID-19 testing, similar to what has been observed throughout the HIV epidemic, making community networks a potential focus for the promotion of COVID-19 safe practices.

A data-informed approach using individualised dispensing patterns to estimate medicine exposure periods and dose from pharmaceutical claims data.

Pharmaceutical claims data are often used as the primary information source to define medicine exposure periods in pharmacoepidemiological studies. However, often critical information on directions for use and the intended duration of medicine supply are not available. In the absence of this information, alternative approaches are needed to support the assignment of exposure periods. This study summarises the key methods commonly used to estimate medicine exposure periods and dose from pharmaceutical claims data; and describes a method using individualised dispensing patterns to define time-dependent estimates of medicine exposure and dose. This method extends on important features of existing methods and also accounts for recent changes in an individual's medicine use. Specifically, this method constructs medicine exposure periods and estimates the dose used by considering characteristics from an individual's prior dispensings, accounting for the time between prior dispensings and the amount supplied at prior dispensings. Guidance on the practical applications of this method is also provided. Although developed primarily for application to databases, which do not contain duration of supply or dose information, use of this method may also facilitate investigations when such information is available and there is a need to consider individualised and/or changing dosing regimens. By shifting the reliance on prescribed duration and dose to determine exposure and dose estimates, individualised dispensing information is used to estimate patterns of exposure and dose for an individual. Reflecting real-world individualised use of medicines with complex and variable dosing regimens, this method offers a pragmatic approach that can be applied to all medicine classes.

Substance use among vocational trainees in Australia: differences between medical specialties.

BACKGROUND: There have been few large-scale nationally representative studies on the prevalence of substance use among doctors. In addition, the association of different medical specialties with the use of different substances requires further research. AIMS: To investigate how the use of alcohol, tobacco and illicit drugs varied between junior doctors enrolled in different specialty training programmes. METHODS: A secondary analysis was conducted on a national survey of 12 252 Australian doctors. The population of interest was junior doctors currently enrolled in a specialty training programme, termed vocational trainees (VT; n = 1890; 15.4% of the overall sample). Self-report prevalence of current alcohol, tobacco and illicit drug use were assessed and hazardous alcohol use was assessed using the Alcohol Use Disorders Identification Test. Logistic regression was used to examine the association between specialty and substance use, adjusting for demographic characteristics when required. RESULTS: One in six VT reported hazardous levels of alcohol use (n = 268; 17.3%). After adjusting for confounders, the association between the prevalence of alcohol use and the specialties of emergency medicine/intensive care unit (odds ratio (OR) 2.15; 95% confidence interval (CI) 1.40-3.32; P < 0.001), anaesthetics (OR 2.53; 95% CI 1.35-4.76; P = 0.004) and obstetrics/gynaecology (OR 1.89; 95% CI 1.19-3.02; P = 0.007) remained significant. No significant associations were found between tobacco use/illicit drug use/hazardous alcohol use and medical specialty. CONCLUSIONS: While rates of substance use and hazardous alcohol use in VT are similar, if not lower, than the general population, it poses a concern that there are higher rates of alcohol use in certain medical specialties.

Opioid agonist treatment and risk of death or rehospitalization following injection drug use-associated bacterial and fungal infections: A cohort study in New South Wales, Australia.

BACKGROUND: Injecting-related bacterial and fungal infections are associated with significant morbidity and mortality among people who inject drugs (PWID), and they are increasing in incidence. Following hospitalization with an injecting-related infection, use of opioid agonist treatment (OAT; methadone or buprenorphine) may be associated with reduced risk of death or rehospitalization with an injecting-related infection. METHODS AND FINDINGS: Data came from the Opioid Agonist Treatment Safety (OATS) study, an administrative linkage cohort including all people in New South Wales, Australia, who accessed OAT between July 1, 2001 and June 28, 2018. Included participants survived a hospitalization with injecting-related infections (i.e., skin and soft-tissue infection, sepsis/bacteremia, endocarditis, osteomyelitis, septic arthritis, or epidural/brain abscess). Outcomes were all-cause death and rehospitalization for injecting-related infections. OAT exposure was classified as time varying by days on or off treatment, following hospital discharge. We used separate Cox proportional hazards models to assess associations between each outcome and OAT exposure. The study included 8,943 participants (mean age 39 years, standard deviation [SD] 11 years; 34% women). The most common infections during participants' index hospitalizations were skin and soft tissue (7,021; 79%), sepsis/bacteremia (1,207; 14%), and endocarditis (431; 5%). During median 6.56 years follow-up, 1,481 (17%) participants died; use of OAT was associated with lower hazard of death (adjusted hazard ratio [aHR] 0.63, 95% confidence interval [CI] 0.57 to 0.70). During median 3.41 years follow-up, 3,653 (41%) were rehospitalized for injecting-related infections; use of OAT was associated with lower hazard of these rehospitalizations (aHR 0.89, 95% CI 0.84 to 0.96). Study limitations include the use of routinely collected administrative data, which lacks information on other risk factors for injecting-related infections including injecting practices, injection stimulant use, housing status, and access to harm reduction services (e.g., needle exchange and supervised injecting sites); we also lacked information on OAT medication dosages. CONCLUSIONS: Following hospitalizations with injection drug use-associated bacterial and fungal infections, use of OAT is associated with lower risks of death and recurrent injecting-related infections among people with opioid use disorder.

Increase in Depression and Anxiety Among Australian Gay and Bisexual Men During COVID-19 Restrictions: Findings from a Prospective Online Cohort Study.

We examined depression and anxiety prior to and during COVID-19 restrictions in Australian gay and bisexual men (GBM). In an online cohort, a COVID-19-focused survey was conducted in April 2020. During 2019 and in April 2020, 664 GBM completed the Patient Health Questionnaire (PHQ-9, measuring depression) and Generalized Anxiety Disorder Assessment (GAD-7, measuring anxiety). Increased depression and anxiety were defined as a ≥ 5 point increase on the respective scales. Mean PHQ-9 and GAD-7 scores increased between 2019 and 2020 (PHQ-9: from 5.11 in 2019 to 6.55 in 2020; GAD-7: from 3.80 in 2019 to 4.95 in 2020). The proportion of participants with moderate-severe depression (PHQ-9 ≥ 10) increased from 18.8% (n = 125) to 25.5% (n = 169), while the proportion of participants with moderate-severe anxiety (GAD-7 ≥ 10) increased from 12.7% (n = 84) to 17.3% (n = 115). Almost one-quarter of participants (n = 158, 23.8%) had increased depression; in these men, mean PHQ-9 increased from 2.49 in 2019 to 11.65 in 2020 (p < 0.001). One-in-five (20.6%) participants (n = 137) had increased anxiety; among these men, mean GAD-7 increased from 2.05 in 2019 to 10.22 in 2020 (p < 0.001). Increases were associated with concerns about job security, reduction in social and sexual connections and opportunities, and being personally concerned about COVID-19 itself. COVID-19 appeared to have a sudden and pronounced impact on depression and anxiety in Australian GBM, with a significant minority showing sharp increases. Ongoing monitoring is required to determine longer-term impacts and GBM need access to appropriate and sensitive supports both during and after the COVID-19 pandemic.

Mood and Anxiety Symptoms in Persons Taking Prescription Opioids: A Systematic Review with Meta-Analyses of Longitudinal Studies.

OBJECTIVE: To review evidence from longitudinal studies on the association between prescription opioid use and common mood and anxiety symptoms. DESIGN: We conducted a systematic review and meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. METHODS: We searched PubMed, Embase, and PsycINFO for search terms related to opioids AND (depression OR bipolar OR anxiety OR post-traumatic stress disorder [PTSD]). Findings were summarized narratively, and random-effects meta-analyses were used to pool effect sizes. RESULTS: We identified 10,290 records and found 10 articles that met our inclusion criteria. Incidence studies showed that people who used prescription opioids had an elevated risk of any mood outcome (adjusted effect size [aES] = 1.80 [95% confidence interval = 1.40-2.30]) and of an anxiety outcome (aES = 1.40 [1.20-1.80]) compared with those who did not use prescription opioids. Associations with depression were small and not significant after adjustment for potential confounders (aES = 1.18 [0.98-1.41]). However, some studies reported an increased risk of depressive symptoms after increased (aES = 1.58 [1.30-1.93]) or prolonged opioid use (aES = 1.49 [1.19-1.86]). CONCLUSIONS: Mental health should be considered when opioids are prescribed because some patients could be vulnerable to adverse mental health outcomes.

Comorbidity between mood and substance-related disorders: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Evidence indicates that mood disorders often co-occur with substance-related disorders. However, pooling comorbidity estimates can be challenging due to heterogeneity in diagnostic criteria and in the overall study design. The aim of this study was to systematically review and, where appropriate, meta-analyse estimates related to the pairwise comorbidity between mood disorders and substance-related disorders, after sorting these estimates by various study designs. METHODS: We searched PubMed (MEDLINE), Embase, CINAHL and Web of Science for publications between 1980 and 2017 regardless of geographical location and language. We meta-analysed estimates from original articles in 4 broadly defined mood and 35 substance-related disorders. RESULTS: After multiple eligibility steps, we included 120 studies for quantitative analysis. In general, regardless of variations in diagnosis type, temporal order or use of adjustments, there was substantial comorbidity between mood and substance-related disorders. We found a sixfold elevated risk between broadly defined mood disorder and drug dependence (odds ratio = 5.7) and fivefold risk between depression and cannabis dependence (odds ratio = 4.9) while the highest pooled estimate, based on period prevalence risk, was found between broadly defined dysthymic disorder and drug dependence (odds ratio = 11.3). Based on 56 separate meta-analyses, all pooled odds ratios were above 1, and 46 were significantly greater than 1 (i.e. the 95% confidence intervals did not include 1). CONCLUSION: This review found robust and consistent evidence of an increased risk of comorbidity between many combinations of mood and substance-related disorders. We also identified a number of under-researched mood and substance-related disorders, suitable for future scrutiny. This review reinforces the need for clinicians to remain vigilant in order to promptly identify and treat these common types of comorbidity.

"Frustrated with the whole system": a qualitative framework analysis of the issues faced by people accessing health services for chronic pain.

BACKGROUND: Chronic non-cancer pain (CNCP) is complex and often requires multimodal management comprising of both pharmacological and non-pharmacological treatments. To inform delivery of CNCP management, it is important to understand how current health services providing non-pharmacological treatments are accessed by exploring the experiences of people attempting to access services. In doing so, this study sought to explore the underlying drivers of service access barriers. METHODS: This study explored the experiences of Australians accessing services for CNCP using semi-structured telephone interviews undertaken between 01 October 2020 and 31 March 2021. Thematic analysis was guided by Levesque et al.'s 2013 conceptual framework of access to health care, with emerging themes mapped to five dimensions of accessibility and corresponding abilities of consumers: Approachability/Ability to perceive; Acceptability/Ability to seek; Availability and Accommodation/Ability to reach; Affordability/Ability to pay; and Appropriateness/Ability to engage. RESULTS: The 26 participants (aged 24-78 years, 22 female) reported accessing a range of services including general practitioners (GP), allied health services, and specialised pain clinics, for a variety of conditions. Three themes were mapped to accessibility dimensions (in brackets): 'GP as guide or gatekeeper' (Approachability); 'Outside of my control' (Availability and Accommodation; Affordability); and 'Services aren't always good enough' (Appropriateness). A fourth identified theme illustrated how participants responded to encountering these barriers: 'Leading my own pain management'. Participant experiences suggest problems with the translation of contemporary pain management principles into practice, including continued application of biomedical health models as opposed to the biopsychosocial model, and demonstrate systemic issues with service delivery, including a lack of benchmarking of specialised services. CONCLUSIONS: The identified themes highlight several evidence-to-practice gaps in the delivery of health services for people with CNCP in Australia. To address these gaps, there is a need for improved clinician training, increased investment in specialised pain services, and development of clear primary care pathways for CNCP management for evidence-based multimodal pain management to be accessible and equitable.

Identifying gaps in dual protection from sexually transmissible infections and unintended pregnancies among Australian women: an observational study.

Background Dual protection refers to the simultaneous prevention of sexually transmissible infection (STI) and unintended pregnancies. Optimal contraception and STI prevention strategies sometimes fail to align. Methods Using data from a large nationally representative population-based survey, we analysed the contraception and STI prevention behaviours at the last vaginal intercourse among 2420 heterosexually active women aged 16-34years who had participated in the Second Australian Study of Health and Relationships, 2012-13. Results At their last vaginal intercourse, most women (95%) used contraception and half (49%) used condoms, either as a sole multipurpose method or in conjunction with another type of contraception. Condom use was highest (72%) among women whose most recent partner was a casual or occasional partner, followed by women with a regular partner (59%) and women with a cohabiting regular partner (40%). One-third of the women (34%) used condoms as a sole method, and 14% used oral contraceptives together with a condom. Few women used implants or intrauterine devices (8%) and, among them, very few women also used condoms (<1%). Among the women who used a condom at their last vaginal intercourse, 49% reported both the correct use for STI prevention and consistent condom use during the previous 6months. Among women using condoms, correct and consistent use was also highest among women whose most recent partner was a casual or occasional partner (76%). Conclusions Although almost all women used contraception and half used dual protection, few benefited from the protective effects of using condoms together with highly effective contraception.

Opportunities to Enhance Linkage to Hepatitis C Care Among Hospitalized People With Recent Drug Dependence in New South Wales, Australia: A Population-based Linkage Study.

BACKGROUND: People who inject drugs are at greater risk of hepatitis C virus (HCV) infection and hospitalization, yet admissions are not utilized for HCV treatment initiation. We aimed to assess the extent to which people with HCV notification, including those with evidence of recent drug dependence, are hospitalized while eligible for direct-acting antiviral (DAA) therapy, and treatment uptake according to hospitalization in the DAA era. METHODS: We conducted a longitudinal, population-based cohort study of people living with HCV in the DAA era (March 2016-December 2018) through analysis of linked databases in New South Wales, Australia. Kaplan-Meier estimates were used to report HCV treatment uptake by frequency, length, and cause-specific hospitalization. RESULTS: Among 57 467 people, 14 938 (26%) had evidence of recent drug dependence, 50% (n = 7506) of whom were hospitalized while DAA eligible. Incidence of selected cause-specific hospitalization was highest for mental health-related (15.84 per 100 person-years [PY]), drug-related (15.20 per 100 PY), and injection-related infectious disease (9.15 per 100 PY) hospitalizations, and lowest for alcohol use disorder (4.58 per 100 PY) and liver-related (3.13 per 100 PY). In total, 65% (n = 4898) of those who were hospitalized had been admitted ≥2 times, and 46% (n = 3437) were hospitalized ≥7 days. By the end of 2018, DAA therapy was lowest for those hospitalized ≥2 times, for ≥7 days, and those whose first admission was for injection-related infectious disease, mental health disorders, and drug-related complications. CONCLUSIONS: Among people who have evidence of recent drug dependence, frequent hospitalization-particularly mental health, drug, and alcohol admissions-presents an opportunity for engagement in HCV care.

Association Between Opioid Agonist Therapy and Testing, Treatment Uptake, and Treatment Outcomes for Hepatitis C Infection Among People Who Inject Drugs: A Systematic Review and Meta-analysis.

BACKGROUND: People who inject drugs (PWID) experience barriers to accessing testing and treatment for hepatitis C virus (HCV) infection. Opioid agonist therapy (OAT) may provide an opportunity to improve access to HCV care. This systematic review assessed the association of OAT and HCV testing, treatment, and treatment outcomes among PWID. METHODS: Bibliographic databases and conference presentations were searched for studies that assessed the association between OAT and HCV testing, treatment, and treatment outcomes (direct-acting antiviral [DAA] therapy only) among PWID (in the past year). Meta-analysis was used to pool estimates. RESULTS: Of 9877 articles identified, 22 studies conducted in Australia, Europe, North America, and Thailand were eligible and included. Risk of bias was serious in 21 studies and moderate in 1 study. Current/recent OAT was associated with an increased odds of recent HCV antibody testing (4 studies; odds ratio (OR), 1.80; 95% confidence interval [CI], 1.36-2.39), HCV RNA testing among those who were HCV antibody-positive (2 studies; OR, 1.83; 95% CI, 1.27-2.62), and DAA treatment uptake among those who were HCV RNA-positive (7 studies; OR, 1.53; 95% CI, 1.07-2.20). There was insufficient evidence of an association between OAT and treatment completion (9 studies) or sustained virologic response following DAA therapy (9 studies). CONCLUSIONS: OAT can increase linkage to HCV care, including uptake of HCV testing and treatment among PWID. This supports the scale-up of OAT as part of strategies to enhance HCV treatment to further HCV elimination efforts.

Progress Towards Elimination of Hepatitis C Infection Among People Who Inject Drugs in Australia: The ETHOS Engage Study.

BACKGROUND: Evaluating progress towards hepatitis C virus (HCV) elimination is critical. This study estimated prevalence of current HCV infection and HCV treatment uptake among people who inject drugs (PWID) in Australia. METHODS: The Enhancing Treatment of Hepatitis C in Opioid Substitution Settings Engage is an observational study of PWID attending drug treatment clinics and needle and syringe programs (NSPs). Participants completed a questionnaire including self-reported treatment history and underwent point-of-care HCV RNA testing (Xpert HCV Viral Load Fingerstick; Cepheid). RESULTS: Between May 2018 and September 2019, 1443 participants were enrolled (64% injected drugs in the last month, 74% receiving opioid agonist therapy [OAT]). HCV infection status was uninfected (28%), spontaneous clearance (16%), treatment-induced clearance (32%), and current infection (24%). Current HCV was more likely among people who were homeless (adjusted odds ratio, 1.47; 95% confidence interval, 1.00-2.16), incarcerated in the previous year (2.04; 1.38-3.02), and those injecting drugs daily or more (2.26; 1.43-2.42). Among those with previous chronic or current HCV, 66% (n = 520/788) reported HCV treatment. In adjusted analysis, HCV treatment was lower among females (.68; .48-.95), participants who were homeless (.59; .38-.96), and those injecting daily or more (.51; .31-.89). People aged ≥45 years (1.46; 1.06-2.01) and people receiving OAT (2.62; 1.52-4.51) were more likely to report HCV treatment. CONCLUSIONS: Unrestricted direct-acting antiviral therapy access in Australia has yielded high treatment uptake among PWID attending drug treatment and NSPs, with a marked decline in HCV prevalence. To achieve elimination, PWID with greater marginalization may require additional support and tailored strategies to enhance treatment.

High hepatitis C treatment uptake among people with recent drug dependence in New South Wales, Australia.

BACKGROUND & AIMS: High HCV treatment uptake among people at most risk of transmission is essential to achieve elimination. We aimed to characterise subpopulations of people with HCV based on drug dependence, to estimate direct-acting antiviral (DAA) uptake in an unrestricted treatment era, and to evaluate factors associated with treatment uptake among people with recent drug dependence. METHODS: HCV notifications in New South Wales, Australia (1995-2017) were linked to opioid agonist therapy (OAT), hospitalisations, incarcerations, HIV notifications, deaths, and prescription databases. Drug dependence was defined as hospitalisation due to injectable drugs or receipt of OAT, with indicators in 2016-2018 considered recent. Records were weighted to account for spontaneous clearance. Logistic regression was used to analyse factors associated with treatment uptake among those with recent drug dependence. RESULTS: 57,467 people were estimated to have chronic HCV throughout the DAA era. Treatment uptake was highest among those with recent (47%), compared to those with distant (38%), and no (33%) drug dependence. Among those with recent drug dependence, treatment was more likely among those with HIV (adjusted odds ratio [aOR] 1.71; 95% CI 1.24-2.36), recent incarceration (aOR 1.10; 95% CI 1.01-1.19), and history of alcohol use disorder (aOR 1.22; 95% CI 1.13-1.31). Treatment was less likely among women (aOR 0.78; 95% CI 0.72-0.84), patients of Indigenous ethnicity (aOR 0.75; 95% CI 0.69-0.81), foreign-born individuals (aOR 0.86; 95% CI 0.78-0.96), those with outer-metropolitan notifications (aOR 0.90; 95% CI 0.82-0.98), HBV coinfection (aOR 0.69; 95% CI 0.59-0.80), and >1 recent hospitalisation (aOR: 0.91; 95% CI 0.84-0.98). CONCLUSIONS: These data provide evidence of high DAA uptake among people with recent drug dependence, including those who are incarcerated. Enhancing this encouraging initial uptake among high-risk populations will be essential to achieve HCV elimination. LAY SUMMARY: To facilitate HCV elimination, those at highest risk of infection and transmission are a treatment priority. This study shows the successes of Australia's universal provision of DAA therapy in reducing the barriers to treatment which have historically persisted among people who inject drugs. Despite higher DAA therapy uptake among those with recent drug dependence, gaps remain. Strategies which aim to reduce marginalisation and increase treatment uptake to ensure equitable HCV elimination must be advanced.

Leveraging genome-wide data to investigate differences between opioid use vs. opioid dependence in 41,176 individuals from the Psychiatric Genomics Consortium.

To provide insights into the biology of opioid dependence (OD) and opioid use (i.e., exposure, OE), we completed a genome-wide analysis comparing 4503 OD cases, 4173 opioid-exposed controls, and 32,500 opioid-unexposed controls, including participants of European and African descent (EUR and AFR, respectively). Among the variants identified, rs9291211 was associated with OE (exposed vs. unexposed controls; EUR z = -5.39, p = 7.2 × 10-8). This variant regulates the transcriptomic profiles of SLC30A9 and BEND4 in multiple brain tissues and was previously associated with depression, alcohol consumption, and neuroticism. A phenome-wide scan of rs9291211 in the UK Biobank (N > 360,000) found association of this variant with propensity to use dietary supplements (p = 1.68 × 10-8). With respect to the same OE phenotype in the gene-based analysis, we identified SDCCAG8 (EUR + AFR z = 4.69, p = 10-6), which was previously associated with educational attainment, risk-taking behaviors, and schizophrenia. In addition, rs201123820 showed a genome-wide significant difference between OD cases and unexposed controls (AFR z = 5.55, p = 2.9 × 10-8) and a significant association with musculoskeletal disorders in the UK Biobank (p = 4.88 × 10-7). A polygenic risk score (PRS) based on a GWAS of risk-tolerance (n = 466,571) was positively associated with OD (OD vs. unexposed controls, p = 8.1 × 10-5; OD cases vs. exposed controls, p = 0.054) and OE (exposed vs. unexposed controls, p = 3.6 × 10-5). A PRS based on a GWAS of neuroticism (n = 390,278) was positively associated with OD (OD vs. unexposed controls, p = 3.2 × 10-5; OD vs. exposed controls, p = 0.002) but not with OE (p = 0.67). Our analyses highlight the difference between dependence and exposure and the importance of considering the definition of controls in studies of addiction.

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

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