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Opioids Part 1 Epidemiology of illicit use Complications Prescription opioid use. © 2010 University of Sydney. Learning Objectives. To be able to: Describe the prevalence of illicit opioid use and dependence Understand the complications of injecting drug use, including opioids
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Opioids Part 1Epidemiology of illicit use ComplicationsPrescription opioid use © 2010 University of Sydney
Learning Objectives To be able to: Describe the prevalence of illicit opioid use and dependence Understand the complications of injecting drug use, including opioids Describe the prevalence of prescription opioid use Explain how to prescribe opioids responsibly to reduce risk of iatrogenic dependence
Overview Epidemiology of illicit opioid use Factors affecting substance use Complications Psychosocial Medical Viral infections Overdose Prevention Prescription drug use Responsible prescribing of opioids
Mr. J Mr J, aged 24 , was recently released from jail Commenced illicit drug experimentation at age 12 No home or major personal problems, just fell in with friends that were ‘into things’ Intermittent heroin use (mainly using stimulants) from age 14 to 19, then daily heroin use; dependence ensued Questions: How common is heroin use? Who is more likely to develop problems with heroin? What are the associated risks?
Epidemiology of substance abuse Prevalence Patterns of use Recent trends
Assessing Prevalence of Drug Use Household surveys of representative samples Illicit Drug Reporting Scheme Utilises multiple sources of users and their contacts Consequences Deaths, treatment seeking, crime
Life-time prevalence of drug use in Australia 2007 • Note: Heroin: 1.6% (0.3 million); Mean age of initiation of life-time use: 29 years. • Household surveys underestimate use of stigmatised substances • Data Source: AIHW (2008) 2007 NDS Household Survey
Lifetime use of heroin (by age and gender) Data Source: AIHW (2008) 2007 NDS Household Survey
Recent use of heroin Data Source: AIHW (2008) 2007 NDS Household Survey
Recent use of heroin Males are more likely than females to have used heroin in the last 12 months ♂ 0.3% vs ♀ 0.1% or ♂ 25,900 vs ♀ 10.300 The highest proportion of recent users found among 20-29 y.o. males 0.7% (10,700) AIHW (2008) 2007 NDS Household Survey
Heroin - patterns of use Most users inject heroin However, a significant proportion ‘smoke’ heroin, inhaling the vapour. Known as ‘chasing the dragon’ Polydrug use is common Experimental and recreational use more common than dependent use Risks - especially of Hep C and overdose Long-term dependent user has the largest impact on public health and order Dependent use usually daily use by injection (1-2 years from 1st use to daily use)
Heroin use among Injecting Drug Users (IDUs) 2009 National sample: N=881 Heroin is the drug of choice (52% of IDUs) 64% of heroin users inject ~ 3 times a week (in the last six months) 15% use daily Stafford J., & Burns, L. Drug Trends Bulletin, December 2009. (NDARC)
Estimated number of heroin dependent users in Australia Data source: Degenhardt et al 2004, NDARC
Dependent heroin users Dependent heroin users 65% male; age varies (median 30-35 years); evidence of aging cohort in Australia >90% English speaking Indigenous 10-15% Imprisonment ~50% Unemployment/pension >80% Homelessness ~10% Day C, et al (2006) Drug Alcohol Rev. 25(4):307-13
Complications Psychological Social Medical Drugs
Psychosocial complications of heroin use Generally severe. Why? Illicit Stigmatized Expensive Grossly intoxicating (contrast with tobacco)
Social consequences Illicit nature Imprisonment rate up to 50% (60% of prisoners are incarcerated for drug-related crime, 20% for alcohol-related crimes) Stigmatised Alienation from parents, spouse and children Discrimination in workplace, health care Expensive : $50-200 per day Involvement in crime (theft, dealing, importation) Prostitution Homelessness and debt to unscrupulous drug dealers predispose users to becoming victims of violent crime. Intoxication Inability to complete education or keep jobs Difficulties caring for children; family breakdown may result
Medical complications Non-specific to opioids Infections Viral*, bacterial, fungal Vascular damage Venous, arterial, pulmonary Glomerulonephritis Not common, but severe complication of injecting drug use Rabdomyolysis and acute renal failure Not common, but severe complication resulting from compartment syndrome (caused by prolonged period of unconsciousness) Malnutrition Trauma * Major causes of harm - discussed in this topic
Medical complications (cont) Specific to opioids Overdose* Dental caries Mostly due to suppressed secretion of saliva May cause acute or chronic pain, dental infections * Major causes of harm - discussed in this topic
Infections due to IDU Viral Caused by blood borne viruses (BBV) HIV/AIDS, Hepatitis C (HCV), Hepatitis B (HBV) Bacterial Abscess, cellulitis, necrotising fasciitis, thrombophlebitis Pneumonia Endocarditis: R>L sided, Staph Aureus Fungal Mostly Candida albicans, local or systemic
Transmission of viral infections: Needle sharing Sharing needles and other injecting equipment or “works” (syringes, spoons, filters and blood-contaminated water) is an important route of transmission of the blood born viral infections Is three times more likely to transmit HIV than sexual intercourse1 Is the most common mode of HCV transmission2 Is the most common risk factor for HBV in adults3 Needle sharing has reduced with introduction of Needle and Syringe Programs (NSP) 1Avert.org (2009). 2ASHM and NCHECR (2008) An overview of hepatitis C: Clinical management in opiate pharmacotherapy settings. 3 Dore et al. (2005) Hepatitis B in Australia: Responding to a Diverse epidemic. (NCHECR)
Needle sharing (2004-2008) Source: NCHECR (2009) Australian NSP survey: National data report 2004-2008
HIV antibody prevalence in IDUs (Australia) HIV prevalence low: 1.5% Lower that in parts of USA, UK, Europe and Asia Reduced due to NSP, peer education and opioid maintenance programs Prevalence is higher in: Homosexual males Predominantly methamphetamine users (reporting as last drug injected), compared to heroin NCHECR (2009) Australian NSP survey: National data report 2004-2008
HIV prevalence by gender and sexual identity Source: NCHECR (2009) Australian NSP survey: National data report 2004-2008.
HIV prevalence by drug last injected NCHECR (2009) Australian NSP survey: National data report 2004-2008
HCV antibody prevalence in IDUs HCV prevalence high, stable at 62% Transmission reduced but not prevented by NSP Higher prevalence pre-NSP, compared to HIV Prevalence higher in users who are: Older that 30 years of age and with a longer history of injecting 20% among those injecting for less than one year 50% - injecting for 8 or 9 years 75% - injecting for 20 years or longer Using predominantly heroin (reported as last drug injected compared to those reporting methamphetamine) Imprisoned in the year prior to survey From Indigenous background NCHECR (2009) Australian NSP survey: National data report 2004-2008
HCV prevalence by years of IDU NCHECR (2009) Australian NSP survey: National data report 2004-2008
HCV prevalence by drug last injected NCHECR (2009) Australian NSP survey: National data report 2004-2008
Hepatitis B in IDUs1 More than 40% of acute hepatitis B cases result from unsafe use of injecting drugs Risk related to duration of injecting: up to 50% HBVcAb+ in long term users Less government support compared to programs aimed at reduction of HIV and HCV Vaccination of IDUs against HBV is available and should be strongly recommended. 1 Dore et al. (2005) Hepatitis B in Australia: Responding to a Diverse epidemic.
Intravenous Drug Use in prison High risk practices persist 75% continue some IDU in prison 80% share needles in prison (cf 20% in community) 10% of prison-IDU started in prison High number of injecting partners 5 partners inside v 1 outside Dolan, K. (1997) in Harm Reduction in Prison, Nedles & Fuhrer (Eds.); Dolan, K. A. (2001) Medical Journal of Australia, 174, 378-379.
IDU in prison: Confiscated needles and syringes
Source: Mouzos J and Smith L (2007) Of Substance, 5(4):21. Reprinted with permission.
Mental Health Mental health problems are common among opioid users. Related to dependence and associated lifestyle Complex relationship and interaction between mental health and dependence
Prevalence Prevalence of mental health problems among opioid dependent treatment seekers Suicide 34% lifetime history of attempted suicide 13% attempted suicide in the last 12 months1 Depression 25% reported current major depressive episode2 Post traumatic stress syndrome (PTSD) 92% exposed to trauma 41% lifetime PTSD3 1 Darke, S. et al (2004) Drug and Alcohol Dependence, 73, 1-10. 2 Teesson, M. et al (2005) Drug and Alcohol Dependence, 78, 309-315. 3 Mills, KL et al (2005) Drug and Alcohol Dependence, 77, 243-249.
Opioid overdose Relatively common among heroin and other opioid users Life-threatening Death from respiratory depression
Risk factors for opioid overdose Polydrug use: Concurrent alcohol & benzodiazepines use Common in fatal and non-fatal overdoses Variable purity (not the major factor) Reduced tolerance to opioids e.g. recently released from prison, not on treatment program Injecting alone (common in fatal overdoses) Not seeking help Absence of others or fear of police involvement Ineffective interventions often tried first by bystanders
Rates of heroin overdose High in Australia in 1997-1999 Significant reduction in 2001, consistent with reduced availability of heroin Overdose remains a major cause of heroin-related harm
Fatal opioid overdose rate Source: Drug and Alcohol Office, Government of Western Australia (2008) Overview of Trends in Opioid Related Mortality. Statistical Bulletin No. 40, February 2008, p.3.
Preventing and reducing harm from injecting heroin use Non-injecting route of administration Advice on safe injecting Professional or peer education Needle Syringe Programs (NSPs) Medically Supervised Injecting Centre Overdose interventions Hep B Vaccination Treatment programs
Needle and Syringe Programs (NSP) One of the principal harm reduction measures Aim to curb the spread of HIV among injecting drug users First program established in Amsterdam in 1983 Now exist in more than 40 countries Provide access to sterile syringes to reduce the risk of IDUs coming into contact with other users’ infected blood Reduce the number of new HIV diagnoses without encouraging drug use Have potential to increase recruitment into drug treatment and into primary health care WHO (2004) Effectiveness of Sterile Needle and Syringe Programming in Reducing HIV/AIDS Among Injecting Drug Users.
Commenced 1986 Widespread and publicly funded Bipartisan support General public support1 Fixed site, outreach, vending machines and pharmacy Public, private and NGO operated Distribution rather than exchange NSPs in Australia 1Treloar & Fraser (2007) Drug Alcohol Rev, 26: 355-361
NSP outcomes in Australia Number of distributed needles and syringes increased during the past decade (from ~27 million to ~31 million) Needle sharing by IDUs reduced: ~30% of users in 19951 ~10-20% in 2004, stable since then2 Effectiveness of NSPs (2000-08)2 NSPs have directly averted: • ~30,000 new HIV infections • ~100,000 new HCV infections Annual national incidence of HIV and HCV among IDUs decreased: HIV - from 39 to 24 HCV - from ~13,000 to ~8,000 1NCHECR (2003) Australian NSP Survey National Data Report 1995-2002. 2NCHECR (2009) Australian NSP survey: National data report 2004-2008.
Overdose interventions Peer education Avoid polydrug use Avoid injecting alone Call an ambulance Naloxone administration Protocols to limit police intervention at overdose resuscitation Supervised injecting rooms
Treatment Programs in Prison Assessment of dependence Management of intoxication and withdrawal Education, counselling Opioid Treatment Programs (OTP) Those who remain in OTP 8/12 post -release have significant reduction in recidivism & mortality1&2 1Dolan, KA (2001) Medical Journal of Australia, 174, 378-379. 2Dolan, KA et al (2005) Addiction, 100, 820-828.
Prescription opioid use Significant increase in number of prescriptions for codeine in the 1990s, peaking in 1999, use now declining Dramatic rise in the use of oxycodone between 2001 and 20071 Increasing steadily (by ~20% per year) since 2001 Sharp increase in 2001-02 when generic oxycodone sustained release became available Increase in the use of tramadol between 2001 and 2004 (plateau in 2004-2007)1 Major harms: Spread of opioid dependence Risk of overdose Risks associated with non-sterile injection and needle sharing 1Leong M et al (2009) Intern Med J, 39(10):676-81.