Louisa Degenhardt

Louisa Degenhardt
UNSW Sydney | UNSW · National Drug and Alcohol Research Centre

MPsychology (Clinical), PhD

About

1,030
Publications
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157,986
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Publications

Publications (1,030)
Article
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Background Disadvantage and transgenerational trauma contribute to Aboriginal and Torres Strait Islander (Indigenous) Australians being more likely to experience adverse health consequences from alcohol and other drug use than non-Indigenous peoples. Addressing these health inequities requires local monitoring of alcohol and other drug use. While c...
Article
Introduction Stigma has corrosive effects on all aspects of care and can undermine individual and population health outcomes. Addiction-related stigma has implications for opiate agonist treatment (OAT) and the people who receive, provide and fund it. It is important to understand how stigma is made in OAT and the political purposes that it serves,...
Article
Background Injecting-related skin and soft tissue infections (SSTIs) are a preventable cause of inpatient hospitalisation among people who inject drugs (PWID). This study aimed to determine the prevalence of hospitalisation for SSTIs among PWID, and identify similarities and differences in factors associated with hospitalisation for SSTIs versus no...
Article
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Purpose Lesbian, gay, and bisexual (LGB) individuals, and LB women specifically, have an increased risk for psychiatric morbidity, theorized to result from stigma-based discrimination. To date, no study has investigated the mental health disparities between LGB and heterosexual AQ1individuals in a large cross-national population-based comparison. T...
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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 reduc...
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This study evaluated HCV treatment initiation among people who inject drugs (PWID) following an intervention of campaign days involving peer connection, point-of-care HCV RNA testing, and linkage to nursing support. ETHOS Engage is an observational cohort study of PWID attending 25 drug treatment clinics and needle and syringe programs in Australia...
Article
Background Evaluating trends in HCV treatment and prevalence is crucial for monitoring elimination. We evaluated the change in current infection and treatment among people who inject drugs (PWID) between 2018-2019 and 2019-2021. Methods ETHOS Engage is an observational cohort study of PWID attending drug treatment clinics and needle and syringe pr...
Article
Background Policies to address opioid-related harms include strategies to reduce opioid prescribing for new and ongoing pain management. Concerns have been raised that people with chronic non-cancer pain (CNCP) may be adversely affected by prescribing restrictions, and by involuntary tapering and cessation of opioids. We describe self-reported chal...
Article
Background Opioid use disorder (OUD) and mental disorders are major public health issues and comorbidity is common. Among people with OUD, comorbid mental disorders are associated with poorer health outcomes. To our knowledge, this is the first systematic review and meta-analysis to estimate prevalence of specific mental disorders among people with...
Article
Aim Exposure to traumatic events (TEs) is associated with substance use disorders (SUDs). However, most studies focus on a single TE, and are limited to single countries, rather than across countries with variation in economic, social and cultural characteristics. We used cross-national data to examine associations of diverse TEs with SUD onset, an...
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Patient‐reported helpfulness of treatment is an important indicator of quality in patient‐centered care. We examined its pathways and predictors among respondents to household surveys who reported ever receiving treatment for major depression, generalized anxiety disorder, social phobia, specific phobia, post‐traumatic stress disorder, bipolar diso...
Article
Background We aimed to characterise opioid analgesic utilisation over a 16-year period among a cohort of people with a history of opioid dependence, comparing rates of use in and out of opioid agonist treatment (OAT). Methods Retrospective cohort study in New South Wales, Australia, including 28,891 people with documented opioid dependence initiat...
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Introduction: To describe trends in methamphetamine use, markets and harms in Australia from 2003 to 2019. Methods: Data comprised patterns of use and price from sentinel samples of people who inject drugs and who use MDMA/other illicit stimulants and population-level amphetamine-related police seizures, arrests, hospitalisations, treatment epis...
Article
Although multimodal management of chronic non-cancer pain (CNCP) is recommended, long-term treatment utilization patterns among people using opioids are not well known. The Pain and Opioids IN Treatment (POINT) study recruited Australian adults receiving opioids for CNCP for more than six weeks from community pharmacies. Pharmacological (opioid and...
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Background Injecting-related bacterial and fungal infections cause substantial illness and disability among people who use illicit drugs. Opioid agonist treatment (OAT) reduces injecting frequency and the transmission of blood borne viruses. We estimated the impact of OAT on hospitalisations for non-viral infections and examine trends in incidence...
Article
Background There are critical periods of mortality risk at onset and cessation of opioid agonist treatment. We aim to determine whether non-fatal overdose followed the same pattern as fatal overdose, comparing the first 4 weeks of treatment and treatment cessation and the remainder time off treatment, with the remainder treatment time, to determine...
Article
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Traditionally, opioid-related disease burden was primarily due to heroin use. However, increases in extra-medical (or non-medicinal use of prescription opioids; NMPOs) use has precipitated the current overdose epidemic in North America. We aim to examine the state-level prevalence of heroin and NMPO dependence and their associations with opioid-rel...
Article
Background: There have been few large-scale nationally representative studies on the prevalence of substance use among doctors. Additionally, the association of different medical specialties with the use of different substances requires further research. Aims: This study aimed to investigate how the use of alcohol, tobacco and illicit drugs vari...
Article
Background Despite the goal set by WHO to eliminate hepatitis C virus (HCV) as a public health threat, uptake of HCV testing and treatment remains low. To achieve this target, evidence-based interventions are needed to address the barriers to care for people with, or at risk of, HCV infection. We aimed to assess the efficacy of interventions to imp...
Article
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 PRISMA guidelines. Methods We searched PubMed, Embase and PsycINFO for search terms related to opioids AND (depression OR bipolar OR...
Article
Background Opioid agonist treatment (OAT) is an effective intervention for opioid dependence. Extended-release buprenorphine injections (BUP-XR) may have additional potential benefits over sublingual buprenorphine. This single-arm trial evaluated outcomes among people receiving 48 weeks of BUP-XR in diverse community healthcare settings in Australi...
Article
Introduction: Opioid agonist treatment (OAT) clients frequently bear costs associated with their treatment, including dosing fees. This study aimed to explore the financial and social impact of dosing fees upon clients. Methods: Cross-sectional survey of people who use opioids regularly (N = 402) between December 2017 and March 2018, conducted i...
Article
Background Identifying solutions to the continued rise in overdose deaths is a public health priority. However, there is evidence of change in recent substance type associated with morbidity and mortality. To better understand the continued rise in overdose deaths, in particular those attributed to opioid and stimulant use disorders, increased know...
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Background: The mental disorders included in the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 were depressive disorders, anxiety disorders, bipolar disorder, schizophrenia, autism spectrum disorders, conduct disorder, attention-deficit hyperactivity disorder, eating disorders, idiopathic developmental intellectual disabili...
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Background A considerable proportion of people who inject drugs are unstably housed. Although unstable housing is associated with HIV and HCV infection among people who inject drugs, its contribution to transmission is unknown. We estimated the global and national proportions of incident HIV and HCV infections among people who inject drugs attribut...
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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...
Article
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 b...
Article
Aim We examined prevalence and factors associated with receiving perceived helpful alcohol use disorder (AUD) treatment, and persistence in help-seeking after earlier unhelpful treatment. Methods Data came from 27 community epidemiologic surveys of adults in 24 countries using the World Health Organization World Mental Health surveys (n = 93,843)....
Article
Background The first 4 weeks after initiation and cessation of opioid agonist treatment for opioid dependence are associated with an increased risk of all-cause mortality and overdose. We aimed to investigate whether the rate of self-harm and suicide among people who were prescribed opioid agonist treatment differs during initiation, cessation, and...
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Aims Major depressive disorder (MDD) is characterised by a recurrent course and high comorbidity rates. A lifespan perspective may therefore provide important information regarding health outcomes. The aim of the present study is to examine mental disorders that preceded 12-month MDD diagnosis and the impact of these disorders on depression outcome...
Article
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Background and aims: The individual-level effectiveness of opioid agonist treatment (OAT) in reducing mortality is well established but there is less evidence on population-level benefits. We use modeling informed with linked data from the OAT program in New South Wales (NSW), Australia, to estimate the impact of OAT provision in community and pri...
Article
Background Little is known about childhood trauma exposure and Opioid Use Disorder (OUD) among people prescribed opioids for chronic non-cancer pain (CNCP). We aimed to (1) describe childhood trauma exposure among this population, and (2) examine if childhood trauma exposure was an independent risk factor for OUD among people prescribed opioids for...
Article
Background: Out-of-pocket costs for opioid agonist treatment (OAT) constitute a barrier to treatment entry and retention.This study examines OAT clients' total out-of-pocket costs (including dispensing fees, travel costs and OAT-related appointment costs) in different treatment settings (public clinics, community pharmacies, and private clinics)....
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Background The sustainable development goals (SDGs) aim to end HIV/AIDS as a public health threat by 2030. Understanding the current state of the HIV epidemic and its change over time is essential to this effort. This study assesses the current sex-specific HIV burden in 204 countries and territories and measures progress in the control of the epid...
Preprint
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Opioid addiction (OA) has strong heritability, yet few genetic variant associations have been robustly identified. Only rs1799971, the A118G variant in OPRM1, has been identified as a genome-wide significant association with OA and independently replicated. We applied genomic structural equation modeling to conduct a GWAS of the new Genetics of Opi...
Article
Background Self-harm in very young people can be a clinically ominous event. While most studies to date have focused on self-harm during the teenage years, fewer studies have examined children aged 12 years or under. We aimed to estimate the incidence and correlates of recent self-harm in a population-based, non-treatment-seeking sample of primary...
Article
Background Adolescents often display heterogenous trajectories of alcohol use. Initiation and escalation of drinking may be an important predictor of later harms. Previous attempts to conceptualise these trajectories lacked adjustment for known confounders of adolescent drinking, which our study has aimed to address by modelling dynamic changes in...
Article
Background: Longer retention in opioid agonist treatment (OAT) is associated with improved treatment outcomes but 12-month retention rates are often low. Innovative approaches are needed to strengthen retention in OAT. We develop and compare traditional and deep learning-extensions of Cox regression to examine the potential for predicting time in...
Article
Background: Understanding factors associated with engagement across the hepatitis C virus (HCV) cascade of care (CoC) among people who inject drugs (PWID) is critical for developing targeted interventions to enhance engagement and further HCV elimination efforts. We describe the CoC among Australian PWID, and identify factors associated with engag...
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Background Identifying differences in unintentional versus intentional drug poisoning deaths can inform targeted prevention. This study aimed to: compare unintentional versus intentional drug poisoning deaths by drug involvement, age and sex; describe patterns of drug involvement by intent; and describe common drug patterns by age and sex. Methods...
Article
Background: Parents are the main supplier of alcohol to children but it is not known whether mothers and fathers equally contribute to the supply of alcohol to their female and male children as these children transition to adulthood. Objectives: i) to determine whether the gender of the parent is associated with the gender of the adolescent offspri...
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Introduction: We examine how smoking and injecting methamphetamine change over time and correlate with specific health and social outcomes. Methods: Panel data from a longitudinal cohort dependent on methamphetamine (N = 444; 891 months). Random effects regression models examined the relationship between smoking and/or injecting methamphetamine...
Article
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Background: Treatment guidelines for generalized anxiety disorder (GAD) are based on a relatively small number of randomized controlled trials and do not consider patient-centered perceptions of treatment helpfulness. We investigated the prevalence and predictors of patient-reported treatment helpfulness for DSM-5 GAD and its two main treatment pa...
Article
Background Overdose is a major cause of morbidity and mortality among people who use opioids. Naloxone can reverse opioid overdoses and can be distributed and administered with minimal training. People with experience of overdose are a key population to target for overdose prevention strategies. This study aims to understand if factors associated w...
Article
Aims To estimate change in young people's alcohol consumption during COVID-19 restrictions in Australia in early-mid 2020, and test whether those changes were consistent by gender and level of consumption prior to the pandemic. Design Prospective longitudinal cohort Setting Secondary schools in New South Wales, Tasmania, and Western Australia. P...
Article
Background: People who inject drugs are at greater risk of hepatitis C virus (HCV) infection and hospitalisation, yet admissions are not utilised 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 hospitalised while eligible for direct-acti...
Article
Importance Mortality among people with opioid dependence is higher than that of the general population. Opioid agonist treatment (OAT) is an effective treatment for opioid dependence; however, there has not yet been a systematic review on the relationship between OAT and specific causes of mortality. Objective To estimate the association of time r...
Article
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A need exists to accurately estimate overdose risk and improve understanding of how to deliver treatments and interventions in people with opioid use disorder in a way that reduces such risk. We consider opportunities for predictive analytics and routinely collected administrative data to evaluate how overdose could be reduced among people with opi...
Article
Aims To describe i) self-reported changes in drug use and ii) trends in price, perceived availability, and perceived purity of illicit drugs, among people who regularly use ecstasy/MDMA and other illicit stimulants in Australia following COVID-19 and associated restrictions. Design Annual interviews with cross-sectional sentinel samples conducted...
Article
Background and Aims There is limited evidence on the relationship between retention in opioid agonist treatment for opioid dependence and characteristics of treatment prescribers. This study estimated retention in buprenorphine and methadone treatment and its relationship with person, treatment and prescriber characteristics. Design Retrospective...
Article
The legality of cannabis use has been changing in a number of jurisdictions around the world. In the U.S., it has been legalised for medicinal and/or recreational uses in 34 jurisdictions and counting. This study leverages the decades-long experience of legalisation in the U.S. to provide an overview of the associated changes in public attitudes, c...
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Importance Despite concern about harms related to long-term prescribed opioid use among individuals with chronic noncancer pain (CNCP), no study has examined whether the same patients engage in a risky pattern of use consistently for the long term. Objective To examine the prevalence, incidence, persistence, and cessation of a range of opioid beha...
Article
The President of the International Association for the Study of Pain established a task force on cannabis and cannabinoid analgesia to systematically examine the evidence on (1) analgesic pharmacology of cannabinoids and preclinical evidence on their efficacy in animal models of injury-related or pathological persistent pain; (2) the clinical effic...
Article
Background Mental disorders (MDs) are known risk factors for suicide. This systematic review updates the evidence base for this association and improves upon analytic approaches by incorporating study-level and methodological variables to account for measurement error in pooled suicide risk estimates. Methods A systematic review was conducted to r...
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Aim: Substance use disorders (SUD) result in substantial morbidity and mortality worldwide. Opioids, and to a lesser extent cocaine, contribute to a large percentage of this health burden. Despite their high heritability, few genetic risk loci have been identified for either opioid or cocaine dependence (OD or CD, respectively). A genome-wide assoc...
Article
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 Jan 2000 and Jul 2019 to catalogue LTOT definitions, the rationale for definitions, and LTOT rates in observa...
Article
Introduction This paper aims to describe cocaine use, markets and harms in Australia from 2003 to 2019. Methods Outcome indicators comprised prevalence of use from triennial household surveys; patterns of use from annual surveys of sentinel samples who use stimulants; and cocaine‐related seizures, arrests, hospitalisations, deaths and treatment ep...
Article
Background Opioid agonist treatment (OAT) reduces many of the harms associated with opioid dependence. We use mathematical modelling to comprehensively evaluate the overall health benefits of OAT in people who inject drugs in Perry County (KY, USA), Kyiv (Ukraine), and Tehran (Iran). Methods We developed a dynamic model of HIV and hepatitis C viru...
Article
Introduction We examined trends in Australian treatment episodes for smoking and injecting methamphetamine from 2003 to 2019. Methods Data from the Alcohol and Other Drug Treatment National Minimum Data Set, where amphetamines were the principal drug of concern, were analysed from 2003 to 2019. Rates were calculated per 100 000 population aged 10–...
Article
Background: Pregabalin has become widely used as an alternative to opioids in treating certain types of chronic non-cancer pain, but few studies have examined its clinical efficacy outside trials. We address this gap by examining the utilization, correlates and clinical outcomes of pregabalin use among an Australian community-based cohort of peopl...
Article
Background People who use illicit opioids have high rates of hospital admission. We aimed to measure the risk of discharge against medical advice among inpatients with a history of opioid agonist therapy (OAT), and test whether OAT is associated with lower risk of discharge against medical advice. Methods We conducted a cohort study of patients ad...
Article
Background There has been much research on the efficacy and effectiveness of opioid agonist treatment (OAT), but less on its implementation and sustainability. A challenge internationally has been recruiting and retaining prescribers. This paper aims to characterise the prescribers in terms of OAT prescribing behaviours. Methods Retrospective coho...
Article
Background Experience of childhood maltreatment (CM) is a risk factor for opioid use disorder (OUD). CM is also associated with comorbid mental disorders and poor treatment outcomes among people with OUD. To our knowledge, this is the first systematic review and meta-analysis to estimate the prevalence of CM among people with OUD. Methods We searc...
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Introduction No prospective studies have examined the prevalence, antecedents or concurrent characteristics associated with self-harm in non-treatment-seeking primary school-aged children. Methods In this cohort study from Melbourne, Australia we assessed 1239 children annually from age 8–9 years (wave 1) to 11–12 years (wave 4) on a range of heal...
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Background and aim Globally, nearly one in five people who inject drugs (PWID) are living with HIV, and the rate of new HIV infections in PWID is increasing in some settings. Early diagnosis is crucial for effective HIV control. We reviewed the evidence on the association between opioid agonist therapy (OAT) and HIV testing uptake among PWID. Meth...
Article
The rapid spread of the coronavirus disease (COVID-19) has impacted the lives of millions around the globe. The COVID-19 pandemic has caused increasing concern among treatment professionals about mental health and risky substance use, especially among those who are struggling with a substance use disorder (SUD). The pandemic's impact on those with...
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Background Variation in liability to cannabis use disorder has a strong genetic component (estimated twin and family heritability about 50–70%) and is associated with negative outcomes, including increased risk of psychopathology. The aim of the study was to conduct a large genome-wide association study (GWAS) to identify novel genetic variants ass...
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Summary Background Rigorous analysis of levels and trends in exposure to leading risk factors and quantification of their effect on human health are important to identify where public health is making progress and in which cases current efforts are inadequate. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 provides a sta...
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Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publ...
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Background The literature suggests patient characteristics and higher opioid doses and long-term duration are associated with problematic opioid behaviours but no one study has examined the role of all these factors simultaneously in a long-term prospective cohort study. Methods Five-year, community-based, prospective cohort of people prescribed o...