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 • 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 100 80 60 40 20 0 Al co h To ol ba An cc o y ill Ca icit nn ab Am E is pe cst as th Ha a m y llu in e ci no s Al gen an s ge si Co c s Tr c an ain e qu ili s In er s ha la nt s H O er th oi er op n io id s G H B Percent (%) Summary of drugs ever used: proportion of the population aged 14 years or older • 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) Lifetime use of heroin (2007) 3.5 3 Percent 2.5 Males 2 Females 1.5 Total 1 0.5 0 14-19 20-29 30-39 40+ Age Data Source: AIHW (2008) 2007 NDS Household Survey 14+ Recent use of heroin Use of heroin in the last 12 months (2007) 0.8 0.7 0.6 Percent 0.5 Males 0.4 Females Total 0.3 0.2 0.1 0 14-19 20-29 30-39 40+ Age Data Source: AIHW (2008) 2007 NDS Household Survey 14+ 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 Viral Infections: Prevalence in IDUs Transmission of viral infections: Needle sharing • Sharing needles and other injecting equipment or “works” (syringes, spoons, filters and bloodcontaminated 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). 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) 2ASHM 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 • 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. 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. 2 Opioid Overdose: Risks and fatality rates 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. Prevention of medical complications 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. NSPs in Australia • • • • • 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 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 2NCHECR (2003) Australian NSP Survey National Data Report 1995-2002. (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, 2Dolan, KA (2001) Medical Journal of Australia, 174, 378-379. KA et al (2005) Addiction, 100, 820-828. Prescription opioid use and responsible prescribing 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. Illicit use of prescription analgesics, including opioids % population 6 Tranquillisers/sleeping pills 5 4 Barbiturates 3 Pain killers/analgesics 2 1 0 1993 1995 1998 2001 2004 2007 Prevalence of prescription drug use for non-medical purposes (Use in the last 12 months, proportion of the population aged 14 years or older, Australia.) Data source: AIHW 2008. 2007 National Drug Strategy Household Survey Responsible prescribing of opioids • Prolonged regular opioid use leads to tolerance and risk of dependence – Avoid use for chronic, non-terminal conditions – Avoid parenteral opioids for recurrent conditions such as migraine, back pain – Be very cautious in prescribing opioids to patients you don’t know • BUT: do manage pain compassionately, even in those with opioid dependence Alternative treatments • Non-steroid anti-inflammatory analgesics • Psychological and other management of pain: e.g. via Pain Clinic • Has the cause been adequately treated? • Consider a drug and alcohol referral for iatrogenic dependence or mixed iatrogenic/abuse picture? Medical prevention issues • Responsible prescribing – Daily dispensing where potential for loss of control over use • Recognise and manage drug-seeking behaviour – Illegal to prescribe S8 drugs to patients with known addiction to these drugs – Say ‘no’ (promptly and courteously: ‘I’m not allowed’, ‘I don’t prescribe … to patients I don’t know’) • Early referral to treatment in a D&A service Legal controls on prescribing (NSW)* • Cannot prescribe opiates where there is known dependence without an authority • Methadone and buprenorphine for opioid dependence – Can only be prescribed by authorised doctors (or nurse practitioners) and with a NSW Health authority for each case *It is important to check your local laws and all laws for accuracy, as they may change. Avoiding deliberate misuse/diversion • Scripts for opiates are usually faxed to chemist if there is risk of tampering • Dose in numerals and words • Controlled dispensing (daily, weekly or similar) from chemist or clinic makes dose escalation or diversion less likely – Can be arranged for any medication with a willing pharmacy – Sometimes a small fee involved Case study: Jane • Jane is aged 36, and presents because panadeine forte (contains codeine 8mg) is no longer controlling her back pain • She is using 40 tablets per day Questions: – What are the risks of her panadeine forte use? – Can you suggest a better treatment? Jane: Answers • 40 tabs = approx 7 tabs every four hours – Risk of paracetamol-induced hepatic damage – Opioid dependence • Jane would be better on a long-acting opioid, if she is unable or unwilling to cease: e.g. methadone or oxycontin • Daily dispensing will help prevent dose escalation • Authority required • Pain Clinic referral may be useful Conclusion (1) • Prevalence of heroin dependence in Australia is low (<1%) • Heroin use is associated with significant medical and psychosocial complications, especially when injected. • Sharing of injecting equipment is the major vector for transmission of blood bourn viral infections. • Introduction of NSPs has prevented the epidemic of HIV, but did not significantly reduce prevalence of HCV infection in Australia – Prevalence of HIV antibodies in IDUs is low (1.5%) – Prevalence of HCV antibodies remains high (65%) but stable • HBV antibodies are present in up to 50% of long term IDUs • Vaccination against HBV is strongly recommended. Conclusion (2) • Mental health problems are common among opioid dependent people (e.g. depression, suicidal ideations, PTSD) • Opioid overdose is the major cause of heroin-related harm • Use prescription opioids with caution because prolonged administration leads to tolerance and risk of dependence • Recognise and manage drug seeking behaviour appropriately • Provide adequate pain relief especially in people with opioid dependence Contributors Associate Professor Kate Conigrave Royal Prince Alfred Hospital & University of Sydney Dr Ken Curry Canterbury Hospital & University of Sydney Dr Carolyn Day University of Sydney Professor Paul Haber Royal Prince Alfred Hospital & University of Sydney Dr Olga Lopatko University of Sydney Professor Richard Mattick National Drug and Alcohol Research Centre, University of New South Wales