The Experts below are selected from a list of 1227 Experts worldwide ranked by ideXlab platform
Matthew Hickman - One of the best experts on this subject based on the ideXlab platform.
-
mortality in the melbourne Injecting Drug User cohort study mix
Harm Reduction Journal, 2015Co-Authors: Dhanya Nambiar, Paul A Agius, Mark Stoove, Matthew Hickman, Paul DietzeAbstract:There are few studies of mortality amongst people who inject Drugs (PWID) in Australia. In this study, we estimate mortality in a cohort of PWID in Melbourne and examine predictors of mortality including health service use, demographic characteristics, Drug use and personal wellbeing. We linked identifiers from the Melbourne Injecting Drug use cohort study (MIX; n = 655) to the National Death Index from 2008 to 2012 to estimate standardised mortality ratios (SMRs). Cox regression was used to examine the bivariate relationship between exposures determined at baseline and subsequent mortality. There were 24 (3.6 %) deaths over the study period. The mortality rate in the cohort was 1.0 per 100 PY (95 % CI 0.71–1.57), with an SMR of 17.3 (95 % CI 11.6–25.8). Baseline reports of four or more lifetime incarcerations (HR 3.65, 95 % CI 1.16–11.52), past month ambulance attendance (HR 4.43, 95 % CI 1.76–11.17), past month emergency department presentation (HR 3.44, 95 % CI 1.47–8.03) and past 6-month self-reported heroin overdose (HR 3.14, 95 % CI 1.24–7.96) were associated with increased mortality risk. Contact with emergency services, particularly for Drug overdose, remains a lost opportunity to provide referrals for harm reduction and naloxone training programmes to PWID at greater risk of mortality.
-
additional file 1 table s1 of mortality in the melbourne Injecting Drug User cohort study mix
2015Co-Authors: Dhanya Nambiar, Paul A Agius, Mark Stoove, Matthew Hickman, Paul DietzeAbstract:Time-varying socio-demographic, risk and health service utilisation factors associated with mortality among PWID in Melbourne (n = 665). (DOC 99 kb)
-
the relationship between alcohol use and Injecting Drug use impacts on health crime and wellbeing
Drug and Alcohol Dependence, 2013Co-Authors: Mark Stoove, Matthew Hickman, Paul Dietze, Campbell Aitken, Rebecca Jenkinson, Damien Jolley, Thomas KerrAbstract:Abstract Background and objectives People who inject Drugs (PWID) are at risk of a variety of adverse outcomes. Previous research suggests that alcohol, when consumed with opioids, is a risk factor for overdose, but there has been less investigation of the effects of alcohol consumption on other health, criminogenic or life satisfaction outcomes. In this paper we explore the effects of alcohol on outcomes for PWID across a variety of life domains. Methods Baseline data were drawn from the Melbourne Injecting Drug User cohort study, which is a cohort of 688 PWID. Drinking scores were generated from the AUDIT-C (0, 1–7, 8+) and associations between them and health (recent heroin overdose, Emergency Department use), criminogenic (violent and nonviolent crime) and life satisfaction (personal wellbeing) outcomes were examined using logistic and linear regression. Results While around 36% of the cohort reported past-month abstinence from alcohol, 44% scored between 1 and 7 and 20% above 7 on the AUDIT-C. A score above 7 was associated with perpetration of violent crime and lower personal wellbeing ratings than a score of 0, after adjusting for potential confounders. There was no association between alcohol and other outcomes examined, after adjustment for confounders. Conclusion Cohort participants who drink heavily were more likely to report engaging in violent crime and poorer life satisfaction. The relationship between alcohol and the offending behaviours of the cohort was consistent with the effects of alcohol on violent offending in the broader community.
-
p53 the cost effectiveness of hcv antiviral treatment for Injecting Drug User populations
Gut, 2011Co-Authors: Natasha K Martin, Peter Vickerman, Graham R Foster, Alec Miners, Sharon J Hutchinson, David J Goldberg, Matthew HickmanAbstract:Introduction Injecting Drug use is the main risk of HCV transmission in most developed countries. Hepatitis C virus antiviral treatment (peginterferon + ribavirin) is cost-effective for patients with no reinfection risk. Concerns about reinfection and non-compliance may discourage clinicians from treating Injecting Drug Users (IDUs), despite the potential use of treatment as prevention in this population. Aim Using a cost-utility analysis, we examined the cost-effectiveness of providing antiviral treatment for IDUs as compared to treating ex/non-IDUs or no treatment. Method A dynamic model of hepatitis C transmission and disease progression among IDUs and ex-/non-IDUs was developed, incorporating: a fixed number of antiviral treatments allocated at the mild HCV stage over 10 years, no retreatment after initial treatment failure, and potential re-infection for cured IDUs. We performed a probabilistic cost-utility analysis estimating long-term costs and outcomes (measured in QALYs) and calculating the incremental cost-effectiveness ratio (ICER) to determine the cost-effectiveness of treating IDUs as compared to treating ex/non-IDUs or no treatment for three baseline IDU HCV prevalence scenarios (20%, 40%, and 60%). Results Antiviral treatment of IDUs is the most cost-effective option in both the 20% and 40% baseline chronic prevalence settings, with ICERs as compared to no treatment (best supportive care) of £521 and £2539 per QALY saved, respectively. Treatment of ex/non-IDUs is dominated in these scenarios. At 60% baseline prevalence, treatment of ex/non-IDUs or IDUs is roughly equally cost-effective; treating ex/non-IDUs is more likely to be the most cost-effective option (with an ICER as compared to no treatment of £6803), and treating IDUs is dominated due to the high re-infection at this prevalence. A sensitivity analysis indicates that these rankings hold even when IDU SVR rates as compared to ex/non-IDUs are halved. Conclusion Despite the possibility of re-infection, the model projections suggest that providing antiviral treatment to IDUs is the most cost-effective policy option in chronic prevalence scenarios
-
can antiviral therapy for hepatitis c reduce the prevalence of hcv among Injecting Drug User populations a modeling analysis of its prevention utility
Journal of Hepatology, 2011Co-Authors: David Goldberg, Natasha K Martin, Peter Vickerman, Graham R Foster, Sharon J Hutchinson, Matthew HickmanAbstract:Background & Aims Hepatitis C virus antiviral treatment is effective for individual patients but few active Injecting Drug Users are treated. We considered the utility of antiviral treatment for primary prevention of hepatitis C. Methods A hepatitis C transmission model among Injecting Drug Users was developed, incorporating treatment (62.5% average sustained viral response) with no retreatment after initial treatment failure, potential re-infection for those cured, equal genotype setting (genotype 1:genotype 2/3), and no immunity. In addition, we examined scenarios with varied treatment response rates, immunity, or retreatment of treatment failures. Results In the baseline scenario, annually treating 10 infections per 1000 Injecting Drug Users results in a relative decrease in hepatitis C prevalence over 10years of 31%, 13%, or 7% for baseline (untreated endemic chronic infection) prevalences of 20%, 40%, or 60%, respectively. Sensitivity analyses show that including the potential for immunity has minimal effect on the predictions; prevalence reductions remain even if SVR is assumed to be 25% lower among active IDU than current evidence suggests; retreatment of treatment failures does not alter the short-term ( Conclusions Despite the possibility of re-infection, modest rates of hepatitis C treatment among active Injecting Drug Users could effectively reduce transmission. Evaluating and extending strategies to treat hepatitis C among active injectors are warranted.
Paul Dietze - One of the best experts on this subject based on the ideXlab platform.
-
How is methamphetamine typically purchased and used in Melbourne, Australia? Reports from a cohort of people who inject Drugs
2016Co-Authors: Nick Scott, Jonathan P. Caulkins, Paul DietzeAbstract:Background: Methamphetamine-related harms have been increasing in Melbourne, Australia, yet little is known of how Users interact with the Drug market. We describe methamphetamine purchases and use as reported by a Melbourne-based cohort of people who inject Drugs (PWID). Methods: A total of 2862 interviews from 757 participants of the Melbourne Injecting Drug User Cohort Study between April 2008 and February 2015 were used to generate descriptive statistics for the: size, search time and setting (e.g. house, street) of methamphetamine purchases, and the percentage that were shared; and the time of day, time between purchasing and using and setting of methamphetamine use. Results: No meaningful differences were observed between the powder and crystal methamphetamine markets. The most frequently purchased amount of methamphetamine was $100 with much larger transactions common; however 42% of purchases were shared, most commonly 50/50 with a partner or friend. The median time to obtain methamphetamine was 20 minutes (interquartile range (IQR) 5–30 minutes) and the median time between purchasing and using methamphetamine was 5 minutes (IQR 5–10 minutes). Most purchases were used between 10 am and 2 pm (43% of purchases), but 33% were used outside of business hours. Both purchasing and using methamphetamine occurred more frequently in houses than public settings. Conclusions: It was common for PWID in our sample to obtain >$100 of methamphetamine with a partner or friend, with relatively little search time. Support services for methamphetamine Users may need to increase their operating hours to adapt to the large amount of use occurring outside of business hours.
-
mortality in the melbourne Injecting Drug User cohort study mix
Harm Reduction Journal, 2015Co-Authors: Dhanya Nambiar, Paul A Agius, Mark Stoove, Matthew Hickman, Paul DietzeAbstract:There are few studies of mortality amongst people who inject Drugs (PWID) in Australia. In this study, we estimate mortality in a cohort of PWID in Melbourne and examine predictors of mortality including health service use, demographic characteristics, Drug use and personal wellbeing. We linked identifiers from the Melbourne Injecting Drug use cohort study (MIX; n = 655) to the National Death Index from 2008 to 2012 to estimate standardised mortality ratios (SMRs). Cox regression was used to examine the bivariate relationship between exposures determined at baseline and subsequent mortality. There were 24 (3.6 %) deaths over the study period. The mortality rate in the cohort was 1.0 per 100 PY (95 % CI 0.71–1.57), with an SMR of 17.3 (95 % CI 11.6–25.8). Baseline reports of four or more lifetime incarcerations (HR 3.65, 95 % CI 1.16–11.52), past month ambulance attendance (HR 4.43, 95 % CI 1.76–11.17), past month emergency department presentation (HR 3.44, 95 % CI 1.47–8.03) and past 6-month self-reported heroin overdose (HR 3.14, 95 % CI 1.24–7.96) were associated with increased mortality risk. Contact with emergency services, particularly for Drug overdose, remains a lost opportunity to provide referrals for harm reduction and naloxone training programmes to PWID at greater risk of mortality.
-
additional file 1 table s1 of mortality in the melbourne Injecting Drug User cohort study mix
2015Co-Authors: Dhanya Nambiar, Paul A Agius, Mark Stoove, Matthew Hickman, Paul DietzeAbstract:Time-varying socio-demographic, risk and health service utilisation factors associated with mortality among PWID in Melbourne (n = 665). (DOC 99 kb)
-
the relationship between alcohol use and Injecting Drug use impacts on health crime and wellbeing
Drug and Alcohol Dependence, 2013Co-Authors: Mark Stoove, Matthew Hickman, Paul Dietze, Campbell Aitken, Rebecca Jenkinson, Damien Jolley, Thomas KerrAbstract:Abstract Background and objectives People who inject Drugs (PWID) are at risk of a variety of adverse outcomes. Previous research suggests that alcohol, when consumed with opioids, is a risk factor for overdose, but there has been less investigation of the effects of alcohol consumption on other health, criminogenic or life satisfaction outcomes. In this paper we explore the effects of alcohol on outcomes for PWID across a variety of life domains. Methods Baseline data were drawn from the Melbourne Injecting Drug User cohort study, which is a cohort of 688 PWID. Drinking scores were generated from the AUDIT-C (0, 1–7, 8+) and associations between them and health (recent heroin overdose, Emergency Department use), criminogenic (violent and nonviolent crime) and life satisfaction (personal wellbeing) outcomes were examined using logistic and linear regression. Results While around 36% of the cohort reported past-month abstinence from alcohol, 44% scored between 1 and 7 and 20% above 7 on the AUDIT-C. A score above 7 was associated with perpetration of violent crime and lower personal wellbeing ratings than a score of 0, after adjusting for potential confounders. There was no association between alcohol and other outcomes examined, after adjustment for confounders. Conclusion Cohort participants who drink heavily were more likely to report engaging in violent crime and poorer life satisfaction. The relationship between alcohol and the offending behaviours of the cohort was consistent with the effects of alcohol on violent offending in the broader community.
Mercedes Weissenbacher - One of the best experts on this subject based on the ideXlab platform.
-
in vitro replication competence of a hepatitis b genotype d a recombinant virus dissimilar biological behaviour regarding its parental genotypes
Journal of General Virology, 2013Co-Authors: Julieta Trinks, Masaya Sugiyama, Yasuhito Tanaka, Fuat Kurbanov, Jorge Benetucci, Edgardo Gimenez, Mercedes Weissenbacher, Masashi Mizokami, Jose Raul OubinaAbstract:Hepatitis B virus (HBV) DNA recombinants contribute to ~30% of the overall full-length sequences already deposited in GenBank. However, their biological behaviour has not been analysed so far. In this study, the in vitro replication kinetics of the first D/A recombinant from the American continent differed from its parental genotypes, exhibiting higher extracellular levels of HBV DNA and hepatitis B e antigen. Southern blots of intracellular core-associated HBV DNA were in agreement with such results. Because this recombinant was obtained from an Argentinian Injecting Drug User belonging to a vulnerable community, these results are of singular relevance for regional public health. Further in vivo studies are urgently needed to determine the pathogenicity of these replicative competent clones.
-
short communication in vitro replication competence of a hepatitis b genotype d a recombinant virus dissimilar biological behaviour regarding its parental genotypes
2013Co-Authors: Julieta Trinks, Masaya Sugiyama, Yasuhito Tanaka, Fuat Kurbanov, Jorge Benetucci, Mercedes Weissenbacher, Masashi MizokamiAbstract:Hepatitis B virus (HBV) DNA recombinants contribute to ~30% of the overall full-length sequences already deposited in GenBank. However, their biological behaviour has not been analysed so far. In this study, the in vitro replication kinetics of the first D/A recombinant from the American continent differed from its parental genotypes, exhibiting higher extracellular levels of HBV DNA and hepatitis B e antigen. Southern blots of intracellular core-associated HBV DNA were in agreement with such results. Because this recombinant was obtained from an Argentinian Injecting Drug User belonging to a vulnerable community, these results are of singular relevance for regional public health. Further in vivo studies are urgently needed to determine the pathogenicity of these replicative competent clones.
Jose Raul Oubina - One of the best experts on this subject based on the ideXlab platform.
-
in vitro replication competence of a hepatitis b genotype d a recombinant virus dissimilar biological behaviour regarding its parental genotypes
Journal of General Virology, 2013Co-Authors: Julieta Trinks, Masaya Sugiyama, Yasuhito Tanaka, Fuat Kurbanov, Jorge Benetucci, Edgardo Gimenez, Mercedes Weissenbacher, Masashi Mizokami, Jose Raul OubinaAbstract:Hepatitis B virus (HBV) DNA recombinants contribute to ~30% of the overall full-length sequences already deposited in GenBank. However, their biological behaviour has not been analysed so far. In this study, the in vitro replication kinetics of the first D/A recombinant from the American continent differed from its parental genotypes, exhibiting higher extracellular levels of HBV DNA and hepatitis B e antigen. Southern blots of intracellular core-associated HBV DNA were in agreement with such results. Because this recombinant was obtained from an Argentinian Injecting Drug User belonging to a vulnerable community, these results are of singular relevance for regional public health. Further in vivo studies are urgently needed to determine the pathogenicity of these replicative competent clones.
Sharon J Hutchinson - One of the best experts on this subject based on the ideXlab platform.
-
estimating the variability in the risk of infection for hepatitis c in the glasgow Injecting Drug User population
Epidemiology and Infection, 2012Co-Authors: Andrew Sutton, Scott A Mcdonald, Norah Palmateer, A Taylor, Sharon J HutchinsonAbstract:Glasgow (Scotland's largest city) has a high prevalence of Injecting Drug use and has one of the highest prevalences of hepatitis C virus (HCV) infection in Injecting Drug Users (IDUs) in Western Europe. HCV prevalence data from surveys of Glasgow's IDUs from 1990 to 2007 were utilized and a model was applied that described the prevalence of HCV as a function of the rate (force) of infection. Force-of-infection estimates for HCV that may vary over time and Injecting career length over a range of variables were investigated. New initiates to Injecting were found to be at increased risk of HCV infection, with being recruited from a street location and reporting Injecting in prison leading to a significant increase in the risk of infection in new initiates. These results indicate areas of importance for the planning of public health measures that target the IDU population.
-
p53 the cost effectiveness of hcv antiviral treatment for Injecting Drug User populations
Gut, 2011Co-Authors: Natasha K Martin, Peter Vickerman, Graham R Foster, Alec Miners, Sharon J Hutchinson, David J Goldberg, Matthew HickmanAbstract:Introduction Injecting Drug use is the main risk of HCV transmission in most developed countries. Hepatitis C virus antiviral treatment (peginterferon + ribavirin) is cost-effective for patients with no reinfection risk. Concerns about reinfection and non-compliance may discourage clinicians from treating Injecting Drug Users (IDUs), despite the potential use of treatment as prevention in this population. Aim Using a cost-utility analysis, we examined the cost-effectiveness of providing antiviral treatment for IDUs as compared to treating ex/non-IDUs or no treatment. Method A dynamic model of hepatitis C transmission and disease progression among IDUs and ex-/non-IDUs was developed, incorporating: a fixed number of antiviral treatments allocated at the mild HCV stage over 10 years, no retreatment after initial treatment failure, and potential re-infection for cured IDUs. We performed a probabilistic cost-utility analysis estimating long-term costs and outcomes (measured in QALYs) and calculating the incremental cost-effectiveness ratio (ICER) to determine the cost-effectiveness of treating IDUs as compared to treating ex/non-IDUs or no treatment for three baseline IDU HCV prevalence scenarios (20%, 40%, and 60%). Results Antiviral treatment of IDUs is the most cost-effective option in both the 20% and 40% baseline chronic prevalence settings, with ICERs as compared to no treatment (best supportive care) of £521 and £2539 per QALY saved, respectively. Treatment of ex/non-IDUs is dominated in these scenarios. At 60% baseline prevalence, treatment of ex/non-IDUs or IDUs is roughly equally cost-effective; treating ex/non-IDUs is more likely to be the most cost-effective option (with an ICER as compared to no treatment of £6803), and treating IDUs is dominated due to the high re-infection at this prevalence. A sensitivity analysis indicates that these rankings hold even when IDU SVR rates as compared to ex/non-IDUs are halved. Conclusion Despite the possibility of re-infection, the model projections suggest that providing antiviral treatment to IDUs is the most cost-effective policy option in chronic prevalence scenarios
-
can antiviral therapy for hepatitis c reduce the prevalence of hcv among Injecting Drug User populations a modeling analysis of its prevention utility
Journal of Hepatology, 2011Co-Authors: David Goldberg, Natasha K Martin, Peter Vickerman, Graham R Foster, Sharon J Hutchinson, Matthew HickmanAbstract:Background & Aims Hepatitis C virus antiviral treatment is effective for individual patients but few active Injecting Drug Users are treated. We considered the utility of antiviral treatment for primary prevention of hepatitis C. Methods A hepatitis C transmission model among Injecting Drug Users was developed, incorporating treatment (62.5% average sustained viral response) with no retreatment after initial treatment failure, potential re-infection for those cured, equal genotype setting (genotype 1:genotype 2/3), and no immunity. In addition, we examined scenarios with varied treatment response rates, immunity, or retreatment of treatment failures. Results In the baseline scenario, annually treating 10 infections per 1000 Injecting Drug Users results in a relative decrease in hepatitis C prevalence over 10years of 31%, 13%, or 7% for baseline (untreated endemic chronic infection) prevalences of 20%, 40%, or 60%, respectively. Sensitivity analyses show that including the potential for immunity has minimal effect on the predictions; prevalence reductions remain even if SVR is assumed to be 25% lower among active IDU than current evidence suggests; retreatment of treatment failures does not alter the short-term ( Conclusions Despite the possibility of re-infection, modest rates of hepatitis C treatment among active Injecting Drug Users could effectively reduce transmission. Evaluating and extending strategies to treat hepatitis C among active injectors are warranted.
-
the influence of hepatitis c and alcohol on liver related morbidity and mortality in glasgow s Injecting Drug User population
Journal of Viral Hepatitis, 2011Co-Authors: Scott A Mcdonald, Sharon J Hutchinson, P R Mills, Sheila M Bird, John F Dillon, Sharon Cameron, David J GoldbergAbstract:Infection with the hepatitis C virus (HCV) is associated with the development of severe liver disease, but cofactors – namely alcohol abuse – in Scotlands HCV-positive population complicate estimation of the unique contribution of HCV. We compared the risk of hospital admission/death for a liver-related cause in a large cohort of Glasgows Injecting Drug Users (IDUs) testing HCV-positive with IDUs testing HCV negative. Data for 6566 current/former IDUs who had been tested for anti-HCV and/or HCV RNA by polymerase chain reaction in Greater Glasgow health board between 1993 and 2007 were linked to the national hospitalization database and deaths registry to identify all admissions and deaths from a liver-related condition. Relative risks were estimated using Cox proportional hazards regression for recurrent events. Time at risk was censored at 2 years following an HCV test to address bias owing to unobserved seroconversion. The risk of hospitalization/death from a liver-related or an alcoholic liver-related condition following HCV testing was greater for those IDUs with no prior alcohol-related hospitalization who tested positive [adjusted hazard ratio (HR) = 3.2, 95% CI:1.5–6.7; 4.9, 95% CI: 1.8–13.1, respectively], compared with those who tested anti-HCV negative, but not for those IDUs with a prior alcohol admission (HR = 0.8, 95% CI: 0.4–1.5; 0.8, 95% CI: 0.4–1.6). There was little evidence for an increased risk of hospitalization/death for an exclusively nonalcoholic liver condition for those testing positive (HR = 1.5, 95% CI: 0.8–2.7), after adjustment for previous alcohol related admission. Within Glasgows IDU population, HCV positivity is associated with an increased risk of a liver-related outcome, but this is not observed for those IDUs whose problem alcohol use already increases their risk
-
p70 can antiviral therapy for hepatitis c reduce the prevalence of hcv among Injecting Drug User populations a modelling analysis of its prevention utility
Gut, 2010Co-Authors: Matthew Hickman, Natasha K Martin, Peter Vickerman, Sharon J Hutchinson, David J Goldberg, Graham R FosterAbstract:Introduction HCV antiviral treatment (peginterferon and ribavirin) is effective for individual patients, but few active Injecting Drug Users (IDUs) are treated. Aim We considered the utility of antiviral treatment for reducing HCV transmission amongst active IDUs. Method An HCV transmission model amongst IDUs was developed, incorporating HCV antiviral treatment. We projected the chronic prevalence reductions resulting from different treatment rates over 5–40 years. Treatment efficacy was varied for three genotype scenarios (mixed, genotype 1, and genotype 2/3) and assumed to result in IDUs becoming susceptible (75%) or resistant/immune (25%). Two models were considered with treatment non-responders either allowed (unrestricted model) or not allowed (restricted model) to be retreated with the same success rates. Results In the unrestricted model with mixed genotype, annually treating 10 infections per 1000 IDUs results in a relative decrease in HCV prevalence over 10 years of 31%, 14% or 7% for baseline (untreated endemic chronic infection) prevalences of 20%, 40% or 60%, respectively. Prevalence reductions are lower (by ∼25% at this treatment level) for populations with all genotype 1 and similarly higher for genotype 2/3 populations. Reduction of prevalence to negligible levels within 20 years could be achieved by treating 21 infections per 1000 IDUs annually with 20% baseline prevalence, increasing to 53 or 99 in the 40% and 60% prevalence situation. Restricting retreatment does not alter the short-term ( 55%). Lastly, the HCV free life years gained from treating active IDUs are projected to be higher than from treating non-IDUs for prevalences below 60%. Conclusion Despite the possibility of re-infection, modest rates of HCV treatment amongst active IDUs could effectively reduce transmission. Evaluating and extending strategies to treat HCV among active injectors is warranted.