opioids part1-2010
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Opioids Part 1Epidemiology of illicit use
ComplicationsPrescription opioid use
© 2010 University of Sydney
Learning ObjectivesTo 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
Summary of drugs ever used: proportion of the population aged 14 years or older
0
20
40
60
80
100
Alcohol
Tobacco
Any illic
it
Cannabis
Ecsta
sy
Ampet
hamin
es
Halluci
nogens
Alanges
ics
Cocaine
Tranquili
sers
Inhala
nts
Heroin
Other o
pioid
sGHB
Pe
rce
nt
(%)
• 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)
0
0.5
1
1.5
2
2.5
3
3.5
14-19 20-29 30-39 40+ 14+
Age
Per
cen
t Males
Females
Total
Data Source: AIHW (2008) 2007 NDS Household Survey
Recent use of heroinUse of heroin in the last 12 months (2007)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
14-19 20-29 30-39 40+ 14+
Age
Pe
rce
nt Males
Females
Total
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
DrugsDrugs
Social Medical
Psychological
Complications
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 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
• 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: 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.
• 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 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.
0
1
2
3
4
5
6
1993 1995 1998 2001 2004 2007
% p
opul
atio
n
Tranquillisers/sleepingpills
Barbiturates
Pain killers/analgesics
Data source: AIHW 2008. 2007 National Drug Strategy Household Survey
Illicit use of prescription analgesics, including opioids
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.)
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
ContributorsAssociate Professor Kate Conigrave Royal Prince Alfred Hospital & University of Sydney
Dr Ken Curry Canterbury Hospital & University of Sydney
Dr Carolyn DayUniversity of Sydney
Professor Paul HaberRoyal Prince Alfred Hospital & University of Sydney
Dr Olga LopatkoUniversity of Sydney Professor Richard MattickNational Drug and Alcohol Research Centre, University of New South Wales