ORCID Profile
0000-0002-5742-4598
Current Organisations
National Drug and Alcohol Research Centre
,
American University of the Middle East
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Publications
Using routinely collected data to understand and predict adverse outcomes in opioid agonist treatment: Protocol for the Opioid Agonist Treatment Safety (OATS) Study
Publisher: BMJ
Date: 08-2018
DOI: 10.1136/BMJOPEN-2018-025204
Abstract: North America is amid an opioid use epidemic. Opioid agonist treatment (OAT) effectively reduces extramedical opioid use and related harms. As with all pharmacological treatments, there are risks associated with OAT, including fatal overdose. There is a need to better understand risk for adverse outcomes during and after OAT, and for innovative approaches to identifying people at greatest risk of adverse outcomes. The Opioid Agonist Treatment and Safety study aims to address these questions so as to inform the expansion of OAT in the USA. This is a retrospective cohort study using linked, routinely collected health data for all people seeking OAT in New South Wales, Australia, between 2001 and 2017. Linked data include hospitalisation, emergency department presentation, mental health diagnoses, incarceration and mortality. We will use standard regression techniques to model the magnitude and risk factors for adverse outcomes (eg, mortality, unplanned hospitalisation and emergency department presentation, and unplanned treatment cessation) during and after OAT, and machine learning approaches to develop a risk-prediction model. This study has been approved by the Population and Health Services Research Ethics Committee (2018HRE0205). Results will be reported in accordance with the REporting of studies Conducted using Observational Routinely-collected health Data statement.
The impact of opioid agonist treatment on fatal and non-fatal drug overdose among people with a history of opioid dependence in NSW, Australia, 2001–2018: Findings from the OATS retrospective linkage
Publisher: Elsevier BV
Date: 07-2022
DOI: 10.1016/J.DRUGALCDEP.2022.109464
Abstract: 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 intervention markers. Retrospective cohort study of people with a history of opioid agonist treatment using linked New South Wales data. The incidence of non-fatal overdose hospitalization emergency department presentation and fatal overdose from national death records were compared. Rates were calculated using generalized estimating equations adjusting for demographics, year, and recent health and incarceration events. The remainder time in OAT had the lowest incidence of overdose for all outcomes and is the reference level for the adjusted incident rate ratios (aIRR). Fatal overdose was lowest in treatment and highest in the first four weeks out of treatment, aIRR of 12.83 (95% CI 10.0-16.4). Whereas the highest overdose rate for non-fatal opioid overdose was in the first four weeks in treatment, aIRR of 3.11 (95% CI 2.19-4.42). Retention on opioid agonist treatment is protective against drug related overdose. There is elevated risk of non-fatal overdose at treatment initiation that is not evident for fatal overdose, but the first month of treatment cessation is a critical period for both non-fatal and fatal overdose. These findings emphasize the importance of treatment retention and interventions for polysubstance overdose at cessation.
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
Publisher: Public Library of Science (PLoS)
Date: 19-07-2022
DOI: 10.1371/JOURNAL.PMED.1004049
Abstract: 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. 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. 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.
Retention of opioid agonist treatment prescribers across New South Wales, Australia, 2001–2018: Implications for treatment systems and potential impact on client outcomes
Publisher: Elsevier BV
Date: 02-2021
Hospitalisations for non-fatal overdose among people with a history of opioid dependence in New South Wales, Australia, 2001–2018: Findings from the OATS retrospective cohort study
Publisher: Elsevier BV
Date: 2021
Risk of discharge against medical advice among hospital inpatients with a history of opioid agonist therapy in New South Wales, Australia: A cohort study and nested crossover-cohort analysis
Publisher: Elsevier BV
Date: 12-2020
Incidence of suicide and self-harm among people with opioid use disorder and the impact of opioid agonist treatment: A retrospective data linkage study
Publisher: Elsevier BV
Date: 05-2023
Life expectancy of people who are dependent on opioids: A cohort study in New South Wales, Australia
Publisher: Elsevier BV
Date: 11-2020
Reductions in emergency department presentations associated with opioid agonist treatment vary by geographic location: A retrospective study in New South Wales, Australia
Publisher: Wiley
Date: 09-2019
DOI: 10.1111/DAR.12976
Mortality during and after specialist alcohol and other drug treatment: Variation in rates according to principal drug of concern and treatment modality
Publisher: Wiley
Date: 25-04-2023
DOI: 10.1111/DAR.13669
Abstract: For people accessing treatment for problems with drugs other than opioids, little is known about the relationship between treatment and mortality risk, nor how mortality risk varies across treatment modalities. We addressed these evidence gaps by determining mortality rates during and after treatment for people accessing a range of treatment modalities for several drugs of concern. We conducted a cohort study using linked data on publicly funded specialist alcohol or other drug treatment service use and mortality for people receiving treatment in New South Wales between January 2012 and December 2018. We calculated and compared during‐treatment and post‐treatment crude mortality rates and age‐ and sex‐standardised mortality rates, separately for each principal drug of concern and modality. Over the study period, 45,026 people accessed treatment for problems with alcohol, 26,407 for hetamine‐type stimulants, 23,047 for cannabinoids and 21,556 for opioids. People treated for alcohol or opioid problems had higher crude mortality rates (1.48, 1.91, 1.09 per 100 person years, respectively) than those with problems with hetamine‐type stimulants or cannabinoids (0.46, 0.30 per 100 person years, respectively). Mortality rates differed according to treatment status and modality only among people with alcohol or opioid problems. The observed variation in mortality rates indicates there is scope to reduce mortality among people accessing treatment with alcohol or opioid problems. Future research on mortality among people accessing drug and alcohol treatment should account for the variation in mortality by drug of concern and treatment modality.
Nonlinear oscillation of second-order dynamic equations on time scales
Publisher: Elsevier BV
Date: 10-2009
Disentangling the costs of male harassment and the benefits of polyandry for females
Publisher: Oxford University Press (OUP)
Date: 18-03-2019
The effect of person, treatment and prescriber characteristics on retention in opioid agonist treatment: a 15‐year retrospective cohort study
Publisher: Wiley
Date: 12-05-2021
DOI: 10.1111/ADD.15514
Abstract: 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. Retrospective longitudinal study. New South Wales, Australia. People entering the opioid agonist treatment programme for the first time between August 2001 and December 2015. Time in opioid agonist treatment (primary outcome) was modelled using a generalized estimating equation model to estimate associations with person, treatment and prescriber characteristics. The impact of medication type on opioid agonist treatment retention reduced over time the risk of leaving treatment when on buprenorphine compared with methadone was higher among those who entered treatment earlier [e.g. 2001–03: odds ratio (OR) = 1.59, 95% confidence interval (CI) = 1.45–1.75] and lowest among those who entered most recently (2013–15: OR = 1.23, 95% CI = 1.11–1.36). In adjusted analyses, risk of leaving was reduced among people whose prescriber had longer tenure of prescribing (e.g. 3 versus 8 years: OR = 0.94, 95% CI = 0.93–0.95) compared with prescribers with shorter tenure. Aboriginal and Torres Strait Islander people, being of younger age, past‐year psychosis disorder and having been convicted of more criminal charges in the year prior to treatment entry were associated with increased risk of leaving treatment. In New South Wales, Australia, retention in buprenorphine treatment for opioid dependence, compared with methadone, has improved over time since its introduction in 2001. Opioid agonist treatment retention is affected not only by characteristics of the person and his or her treatment, but also of the prescriber, with those of longer prescribing tenure associated with increased retention of people in opioid agonist treatment.
Prevalence of opioid dependence in New South Wales, Australia, 2014–16: Indirect estimation from multiple data sources using a Bayesian approach
Publisher: Wiley
Date: 08-06-2023
DOI: 10.1111/ADD.16268
Abstract: To estimate the prevalence of, and number of unobserved people with opioid dependence by sex and age group in New South Wales (NSW), Australia. 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. 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. 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. 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.
Interval oscillation criteria for second-order forced delay dynamic equations with mixed nonlinearities
Publisher: Elsevier BV
Date: 2010
Likely Geographic Distributional Shifts among Medically Important Tick Species and Tick-Associated Diseases under Climate Change in North America: A Review
Publisher: MDPI AG
Date: 05-03-2021
Abstract: Ticks rank high among arthropod vectors in terms of numbers of infectious agents that they transmit to humans, including Lyme disease, Rocky Mountain spotted fever, Colorado tick fever, human monocytic ehrlichiosis, tularemia, and human granulocytic anaplasmosis. Increasing temperature is suspected to affect tick biting rates and pathogen developmental rates, thereby potentially increasing risk for disease incidence. Tick distributions respond to climate change, but how their geographic ranges will shift in future decades and how those shifts may translate into changes in disease incidence remain unclear. In this study, we have assembled correlative ecological niche models for eight tick species of medical or veterinary importance in North America (Ixodes scapularis, I. pacificus, I. cookei, Dermacentor variabilis, D. andersoni, Amblyomma americanum, A. maculatum, and Rhipicephalus sanguineus), assessing the distributional potential of each under both present and future climatic conditions. Our goal was to assess whether and how species’ distributions will likely shift in coming decades in response to climate change. We interpret these patterns in terms of likely implications for tick-associated diseases in North America.
Does opioid agonist treatment reduce overdose mortality risk in people who are older or have physical comorbidities? Cohort study using linked administrative health data in New South Wales, Australia,
Publisher: Wiley
Date: 20-03-2023
DOI: 10.1111/ADD.16178
Abstract: To quantify the association between opioid agonist treatment (OAT) and overdose death by age group test the hypothesis that across different age groups, opioid overdose mortality is lowest during OAT with buprenorphine compared with time out of treatment or OAT with methadone and test associations between OAT and opioid overdose mortality in the presence of chronic circulatory, respiratory, liver and kidney diseases. Retrospective observational cohort study using linked administrative data. New South Wales, Australia. A total of 37 764 people prescribed OAT, 1 August 2002 and 31 December 2017. OAT exposure, opioid overdose mortality and key confounders were measured using linked population data sets on OAT entry and exit, hospitalization, mental health care, incarceration and mortality. ICD‐10 codes were used to define opioid overdose mortality and chronic disease groups of interest. Relative to time out of treatment, time in OAT was associated with a lower risk of opioid overdose death across all age groups and chronic diseases. Among people aged 50 years and older, there was weak evidence that buprenorphine may be associated with greater protection against opioid overdose death than methadone [generalized estimating equation (GEE) adjusted incident rate ratio (aIRR) = 0.47 95% confidence interval (CI) = 0.21, 1.02 marginal structural models (MSM) aIRR = 0.49 95% CI = 0.17, 1.41]. Buprenorphine was associated with greater protection against overdose death than methadone for clients with circulatory (MSM aIRR = 0.27 95% CI = 0.11, 0.67) or respiratory (MSM aIRR = 0.26 95% CI = 0.07, 0.94) diseases, but not liver (MSM aIRR = 0.59 95% CI = 0.14, 2.43) or kidney (MSM aIRR = 1.16 95% CI = 0.31, 4.36) diseases. Opioid agonist treatment (OAT) appears to reduce mortality risk in people with opioid use disorder who are older or who have physical comorbidities. Opioid overdose mortality during OAT with buprenorphine appears to be lower and reduced in clients with circulatory and respiratory diseases compared with OAT with methadone.
Modeling the population-level impact of opioid agonist treatment on mortality among people accessing treatment between 2001 and 2020 in New South Wales, Australia
Publisher: Wiley
Date: 04-12-2022
DOI: 10.1111/ADD.15736
Abstract: The in idual‐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 the community and prisons on mortality and the impact of eliminating excess mortality during OAT initiation/discontinuation. Dynamic modeling. A cohort of 49 359 in iduals who ever received OAT in NSW from 2001 to 2018. Receipt of OAT was represented through five stages: (i) first month on OAT, (ii) short (1–9 months) and (iii) longer (9+ months) duration on OAT, (iv) first month following OAT discontinuation and (v) rest of time following OAT discontinuation. Incarceration was represented as four strata: (i) never or not incarcerated in the past year, (ii) currently incarcerated, (iii) released from prison within the past month and (iv) released from prison 1–12 months ago. The model incorporated elevated mortality post‐release from prison and OAT impact on reducing mortality and incarceration. Among the cohort, mortality was 0.9 per 100 person‐years, OAT coverage and retention remained high ( 50%, 1.74 years/episode). During 2001–20, we estimate that OAT provision reduced overdose and other cause mortality among the cohort by 52.8% [95% credible interval (CrI) = 49.4–56.9%] and 26.6% (95% CrI =22.1–30.5%), respectively. We estimate 1.2 deaths averted and 9.7 life‐years gained per 100 person‐years on OAT. Prison OAT with post‐release OAT‐linkage accounted for 12.4% (95% CrI = 11.5–13.5%) of all deaths averted by the OAT program, primarily through preventing deaths in the first month post‐release. Preventing elevated mortality during OAT initiation and discontinuation could have averted up to 1.4% (95% CrI = 0.8–2.0%) and 3.0% (95% CrI = 2.1–5.3%) of deaths, respectively. The community and prison opioid agonist treatment program in New South Wales, Australia appears to have substantially reduced population‐level overdose and all‐cause mortality in the past 20 years, partially due to high retention.
Interval criteria for second-order super-half-linear functional dynamic equations with delay and advance arguments
Publisher: Informa UK Limited
Date: 08-2010
Related Organisations
University Of Reading
Location: United Kingdom of Great Britain and Northern Ireland
Sheffield Hallam University
Location: United Kingdom of Great Britain and Northern Ireland
Related Funding Activities
No related grants have been discovered for Nicola Jones.