Transcript Kim Woolf presentation – ppt - Australasian College of Road Safety

DRIVING UNDER THE INFLUENCE
OF DRUGS – THE SCIENTIFIC
EVIDENCE
Kim Wolff
Professor of Addiction Science
King’s College London
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2011
UK Government agreed to implement
recommendations from the North Report
Government’s 2011 Framework for Road safety
“…We will explore the case for introducing an
offence of having a specified drug in the body
while driving, in addition to the current offence of
driving whilst impaired by drugs…..”
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LEVEL OF RISK RATHER THAN IMPAIRMENT
Our APPROACH did not seek to define, measure or proportion a
drug level to a certain degree of impairment

Legislation already in place for driving whilst impaired

Where a test is employed to judge a drivers level of impairment
at the road-side: used in England and Wales, Road Traffic Act
1988 Section 4 (UK Government, 1988)

In terms of our ToR defining impairment for different classes of
drugs too complicated

Impairment differs for different classes of drugs:


(stimulants Vs depressants Vs hallucinogens)
There is no universal agreement on how to measure
impairment
CANNABIS
SEVERAL KEY FACTS FOR Δ9- TETRA HYDROCANNABINOL (THC):
1.In
UK adults (16 to 59 yrs.) who reported drug-driving with
illegal drugs (once or twice in the last 12 months)
2.Cannabis as elsewhere is most commonly used illicit drug
in drivers
3.Significant dose related decrement in driving
performance (observed in experimental, real-life, simulator,
laboratory and Forensic Traffic Data): Higher dose – the
worse you drive!
4.Raised THC blood concentration are significantly
associated with increased risk of Traffic Crash and serious
or fatal crash risk
5.Meta-analysis shows mean blood concentration >3.7µg/L
impairs individuals to a degree comparable to blood
alcohol levels 50mg/100mL blood.
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CANNABIS - 2
CANNABIS USE BEHAVIOUR
1.
2.
3.
4.
5.
Smoking a single cannabis cigarette infrequently
(recreational use): higher conc THC (21 µg/L - 162
µg/L) causing acute intoxication
In chronic, daily or near daily use over a
prolonged period (years), steady-state
concentrations of THC ranging between 1 µg/L to
6.4 µg/L
Blood concentrations are maintained by
sequestration of the drug from the tissues: falling to
<1 µg/L after 24 hours abstinence and <0.5 µg/L
after 7 days abstinence.
Passive exposure to cannabis smoke leads to very
low levels of THC: less than 1 µg/L;
There is clearly a case for cannabis.
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CANNABIS – RISK OF RTC
1.
Meta-analysis of over 120 studies: the higher the conc THC in
blood, the greater the driving impairment;
2.
Significant increased crash risk when THC in the blood was ≥ 5
µg/L, whether or not ingestion had occurred recently and
regardless of the origin of the drug (medicinal or illicit)
1.
Wolff & Johnston, 2013
3.
Individuals who drive within 2 hours of using cannabis have
raised rates of collision.
4.
Drivers consuming cannabis 2 or 6 times more likely to be at
risk RTC.
5.
Indeed the risk of a driving accident was increased by 16 times
when cannabis and alcohol were consumed concurrently by
drivers
6.
Possible need to look at alcohol in combination with cannabis
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Positive Sample
THC + EtOH
EtOH
THC
0.5
1
2
4
8
16
32
Odds Ratio (± 95% CI)
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MEDICINAL CANNABINOIDS

Medicinal cannabinoids, providing they are taken in
accordance with directions given by the prescriber,
produce low steady-state blood concentrations of THC
(about 1 μg/L to 2 μg/L).

This is because the amount of THC prescribed is very
low:

Nabilone (Cesamet®) is prescribed in doses ranging
from 2mg to 6mg/day

Nabiximols (Sativex®), an oromucosal spray
containing THC together with cannabidiol (CBD) is
delivered in a fixed dose of 2.7 mg THC and 2.5 mg
CBD.
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WHICH AMPHETAMINE?

Scientific data largely refers to amphetamine,
methamphetamine and MDMA (often combined)

Methamphetamine breaks down in the body into
amphetamine

UK does not see methamphetamine too often

Amphetamine prescribed in drug treatment settings and
for Attention Deficit Hyperactivity Disorder (ADHD)

Seligiline, clobenzorex, famprofazone, fencamine,
furfenorex and prenylamine (amphetamine metabolite)

Other stimulants: Mephedrone, BZP, cathinone, etc - little
data about these substances since laboratories do not
routinely screen for them
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AMPHETAMINE AND
SLEEP
SLEEP DEPRIVATION
Amphetamine
increases
alertness, risk taking, suppresses
sleepiness and tiredness for up
to 6h after dosing
Considered
After
10-40
6h feel restless, overactive and fatigued:
Characterised by sleeplessness
by DRUID
researchers to be equivalent
to 50 mg alcohol/100 ml
Blood
mg amphetamine did
not compensate for poor
driving produced by sleep
deprivation (Hjalmdadhl et al,
2012)
AMPHETAMINE AND SLEEP
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AMPHETAMINE AND
IMPAIRMENT
DRIVERS APPREHENDED
UNDER INFLUENCE OF
AMPHETAMINE
No
Mean
evidence of impairment
at low doses amphetamine:
small doses used by military to
maintain
concentration/wakefulness
At
therapeutic doses plasma
conc not usually more than
200 ug/L
conc in UK 496 ug/L to
651 ug/L
Time
lag between blood
collection and accident
about 2h
Fatigue
after amphetamine
use may be a factor
EVIDENCE REGARDING AMPHETAMINE
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THE EVIDENCE FOR DRIVING RISK
Although amphetamine less prevalent ORs are higher
for risk of RTC following consumption than either
cannabis or cocaine
Amphetamine 4.46 (p<0.05) 2.21 - 9.00
Meta analysis of 8 laboratory studies analysing
presence of amphetamines in drivers fatally injured
in road crashes
Amphetamine 8.88 (p<0.001) 4.54 - 17.39
Case control study (Thailand) comparing urine
methamphetamine
Methamphetamine 8.35 (3.91 - 17.83) Dutch RTCs
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COCAINE
OR suggest 3 times at risk of being seriously injured if
use cocaine and drive
 Driving whilst sleep deprived following cocaine
binge also been reported as problem
 Analytical issues as cocaine fast acting drug
 Would all dangerous driving be captured by
screening for cocaine alone?
 Should benzoylecgonine (BZE) the main metabolite
be considered as well?
 Should a threshold be set for cocaine alone,
Cocaine and BZE or even BZE alone
 Alcohol use and cocaine also a concern

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COCAINE
Substance
OR
CIs
Basis of the OR
Cocaine
2.96 (p<0.05)
1.18 - 7.38
Meta analysis of 4 studies analysing presence of cocaine in drivers fatally
injured in road crashes
Cocaine
3.3
1.40 - 7.79
Analysis of blood samples collected from individuals seriously injured in
RTAs in 6 European countries between 2007-2009
Cocaine
2.04
0.69 - 6.09
Dutch Case-control study comparing 110 drivers hospitalised after a RTA
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SUMMARY – SO FAR
A new offence of driving with certain specified
controlled drugs* in excess of specified WHOLE BLOOD
concentration in the body came into force during
March 2015.
This offence is an addition to the existing rules on drug
impaired driving and fitness to drive.
The legislation also provides for a statutory “medical
defence” for this new offence, for patients taking their
medicines in accordance with instructions.
Controlled drugs are defined in the Misuse of Drugs
Act 1971
Strict liability offence: Fine, lose license, prison
MARCH 2015 NEW LEGISLATION
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LOW LEVEL DETECTION
QUANTIFICATION (LLOQ)
LEGISLATION
RISK BASED EXPERT
PANEL
THC
5 ug/L
THC
2 ug/L
Cocaine
80 ug/L
Cocaine
10 ug/L
BZE
500 ug/L
BZE
50 ug/L
Methylamphetamine
200 ug/L
Methylamphetamine
10 ug/L
MDMA
300 ug/L
MDMA
10 ug/L
Ketamine
200 ug/L
Ketamine
10 ug/L
LSD
1 ug/L
6
5 ug/L
LSD
--------------------------
6-MAM-----------------------
MAM
CUT-OFFS FOR ILLICIT DRUGS IN
BLOOD
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OTHER APPROACHES
Some countries have instigated a programme of zero
tolerance
Equates to a complete ban on the use of a specified
drug whilst driving
Another approach is often referred to as the ‘per se’
approach
Based on the detection of a drug in a driver above a
defined cut-off concentration predominantly in whole
blood
Cut-off concentrations often been linked to risk and
driver safety.
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PRESCRIBED CONTROLLED
DRUGS
Also included in the legislation
Controlled Drug - this is a legal definition and refers to those
drugs that are controlled under the 1971 Act - this regulates
the import, export, possession, supply, and other aspects of
activities relating to those drugs specified in the 1971 Act.
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BENZODIAZEPINES: SEDATIVES/
ANXIOLYTICS
BZ used more in the UK than in Europe by driving
population.
 In Europe women aged 35+, day-time drivers
 DRUID 2-5 times risk RTC compared no BZ
 First 2-4 weeks of prescription Anxiolytics: Diazepam,
Lorazepam and Oxazepam OR: 2.5 to 5.5 having an
accident severe enough to require hospitalisation
Benzodiazepine/driving collaboration group.
BZ and Alcohol OR: 2.00 (alcohol alone 0.2-0.8g/L)
OR: 7.00 (alcohol >0.2g/L + BZ )

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BENZODIAZEPINES:
SEDATIVES/ANXIOLYTICS
1.
2.
3.
4.
DRUID among killed drivers: benzodiazepines was the
second most frequent toxicological finding after alcohol
(DRUID, D2.2.5, 2012, WOMEN AGED 35+, DAY-TIME DRIVERS)
Benzodiazepine deleterious driving behaviour in the older
patient when longer-acting and larger quantities of
benzodiazepines were consumed.
RTC victims aged ≥60 years, benzodiazepines use were
associated with a significantly greater risk of a crash
(OR:5.3,3.6–7.8,p<.001):
Older patients were between 4-6 fold more likely to be
hospitalised following a RTC than others in the same age
group not prescribed benzodiazepines
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DRIVER RISK WITH MEDICATION: SEDATION OR
ANTI-ANXIETY
BENZODIAZEPINES AND Z-DRUGS
Impairment in apprehended drivers in Norway *Adjusted for all
background variables Bramness et al, 2002
Diazepam
Oxazepam
Flunitrazepam
OR: 1.61 (n=/411;P</0.001)
OR: 3.65 (n=/73; P </0.05)
OR: 4.11 (n=/211;(P </0.05)
UK study, Tayside police 19, 386 drivers involved first RTA: Barbone et al
Lancet, 1998
Zopiclone alone
OR: 4.00 (1.31 – 12.2)
Any BZ with positive breath test
OR; 8.15 (2.06-32.34)
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PRESCRIBED MEDICATION: PAIN RELIEF
OPIOIDS usually mean Morphine, Methadone and Diamorphine
together




Acknowledged in Europe that Opiates/opioids
increases risk RTA between 2-10 times
Medicinal opioids seem to have higher risk than illicit
use
Over-the-counter medicine (codeine) little risk if
taken as prescribed
ANY Opiate/Opioid or BZ with any amount of
alcohol significantly increases risk of RTA
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DRIVER RISK AND PAIN RELIEF MEDICATION
Opiates, Opioids, Medicinal opioids:




Odds individuals seriously injured in RTCs in 6 European countries 20072009 when consumed Illicit opiates (heroin/morphine)
 OR 2..47 (0.50 - 12.10)
.
Odds individuals being killed in road accidents in 4 European countries
between 2007-2009 who consumed Illicit opiates
OR 10.04 (2.04 - 49.32 )
Odds individuals being seriously injured in RTCs in 6 European countries
who consumed Medicinal opioids
(methadone/diacetylmorphine/morphine)
OR 9.06 (6.40 - 12.83)
Odds individuals killed in RTCs in 4 European countries between 20072009 who consumed Medicinal opioids
OR 4.82 (2.60 - 8.93)
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METHADONE

Literature mixed about the impact of methadone on driving

Use of other drugs

Blood concentrations between 90 ug/L and 132 ug/L drivers
successfully passed driving test

At high concentrations reaction time and decision time decreases


Decided to set threshold high 500 ug/L
Doses 80 mg and above

BUT use any methadone with alcohol risk RTC increases

Need to report to DVLA

www.gov.uk/government/publications/at-aglancewww.gov.uk/government/publications/at-a-glance

200, 000 M patients 3% known to DVLA
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EXPERT PANEL
LEGISLATION
Methadone
500 ug/L
Methadone
500 ug/L
Amphetamine
600 ug/L
Amphetamine
250 ug/L
Morphine
80 ug/L
Morphine
80 ug/L
Diazepam
550 ug/L
Diazepam
550 ug/L
Oxazepam
300 ug/L
Oxazepam
300 ug/L
Flunitrazepam
300 ug/L
Flunitrazepam
300 ug/L
Clonazepam
50 ug/L
Clonazepam
50 ug/L
Lorazepam
100 ug/L
Lorazepam
100 ug/L
Temazepam
1000 ug/L
Temazepam
1000 ug/L
PRESCRIBED CONTROLLED DRUGS IN
BLOOD
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MEDICAL DEFENCE




Drugs proscribed for driving can be used legitimately, in
accordance with medical advice (CANNABIS for multiple
sclerosis).
Recognised may be more dangerous for a person to drive not
having taken their prescribed medication than driving having
taken it.
The legislation not expected to affect those who are properly
and safely taking medically prescribed drugs and driving in
accordance with medical advice, and for whom, there is no
evidence of driving in an unsafe way.
A statutory defence is available for a driver who has taken a
drug supplied or prescribed for medical purposes and who has
taken the drug in line with directions and instructions. (This is
included in Clause 27 of the Crime and Courts Bill)
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ADVICE………
 It
was deemed helpful for patients to keep some
suitable evidence with them when they are driving
that provides medical confirmation of drug they
are taking (the controlled drug) as a medicine
prescribed or supplied by a healthcare
professional and taken in accordance with the
leaflet accompanying the medicine, in case that
patient was ever stopped by the police.
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ALCOHOL AND DRUG USE
Significant
Alcohol
How
risk with multiple drug use
use multiplies risk
do we deal with this?
Evidence of risk for Alcohol and drugs combined DRUID
(2012)
OR
seriously injured RTC 31.97 (20.76-49.25)
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MULTIPLE DRUG USE
Significant
risk with multiple drug use
Approximately
6 times more risk of a RTC if using
multiple drugs compared with no drug OR: 6.05 (95%
CI: 2.60-14)
If
combine more than one drug with alcohol the risk
of a RTC substantially increases and was estimated to
be more than 100 times as risky as using no drugs at
all
Drugs + alcohol compared with no drugs OR: 112
(95% CI: 14-893)
Movig et al, 2004
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






Stopped by police for driving offence
Breathalysed first
Then drug screen.
Oral Fluid (saliva test) – only test for cannabis
or cocaine at moment
If deemed unfit or impaired or positive
Blood sample at Police Station will test for
all 17 drugs
Image – www.mirror.co.uk
IN PRACTICE
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
At present Blood is the only matrix that can be used as evidence
in a court of law to confirm drug use

Scientific evidence is concerned with Blood (urine not suitable)

Oral Fluid being discussed as a confirmatory matrix but
evidence is not conclusive especially drugs contaminated by
nasal use (heroin, cocaine, cannabis)

Approach in UK – screening device at road side based on
immunoassay using Oral Fluid, then confirmatory blood test at
police station

The time lap between blood sample collection and receipt by
laboratory is vital (<2 hrs)

Chain of custody important: tamper proof drug test kits;
standardised preservatives

Accreditation of laboratory essential
BIOLOGICAL SAMPLES
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DRINK-DRIVE PENALTIES
Being in charge of a vehicle while above the legal limit or unfit through drink
You may get: 3 months’ imprisonment; up to £2,500 fine
a possible driving ban
Driving or attempting to drive while above the legal limit or unfit through drink
You may get: 6 months’ imprisonment; an unlimited fine
a driving ban for at least 1 year (3 years if convicted twice in 10 years)
Refusing to provide a specimen of breath, blood or urine for analysis
You may get: 6 months’ imprisonment; an unlimited fine
a ban from driving for at least 1 year
Causing death by careless driving when under the influence of drink
You may get: 14 years’ imprisonment; an unlimited fine
a ban from driving for at least 2 years; an extended driving test before your
licence is returned
;
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PENALTIES FOR DRUG DRIVING
IF YOU’RE CONVICTED OF DRUG DRIVING YOU’LL
GET:
A MINIMUM 1 YEAR DRIVING BAN
AN UNLIMITED FINE
UP TO 6 MONTHS IN PRISON
A CRIMINAL RECORD
YOUR DRIVING LICENCE WILL ALSO SHOW
YOU’VE BEEN CONVICTED FOR DRUG DRIVING.
THIS WILL LAST FOR 11 YEARS.
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KETAMINE: GROWING EVIDENCE

CSEW: subjects notified for driving under the influence suggested 40%
previous experiences of ketamine intake, either alone or in combination with
other drugs

2012, 13 out of 853 oral fluid specimens taken from random roadside testing
in Victoria were found positive for ketamine (Chu et al, 2012).

More recently, 14 of 376 suspected cases of driving under the influence were
reported to be ketamine-positive individuals (Birch et al, 2013). In this UK
study, ketamine was not included in the standard panel and was assessed
only if suspected.

The mean and median concentrations of KET detected in those cases were
421 and 385 ng/mL, respectively, and the mean and median concentrations
of norketamine, the main metabolite, were 605 and 410 mg/mL,
respectively. Another survey (Bezemer et al, 2014) found that 10 of 3038
blood samples collected from impaired drivers were KET-positive.

Two further studies reported 45% KET positivity among intoxicated drivers
involved in non-fatal traffic accident (Wong et al, 2012) and 9% positivity
among those involved in fatal crashes (Cheng et al, 2005)
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
Driving under the influence of ketamine (Cheng 2007)

Hong Kong
62 volunteers exiting from a dance-event

39 had ketamine detected with in oral fluid.

21 (54%) had only used ketamine

Others used MDMA, benzodiazepines and/or
THC)

15 successfully identified by FIT

Impairment greatest concentration >300 ug/L.

Clinical reports (Weiner et al, 2000)

“Moderate” to “extreme” disturbance of perceptions at
200 ug/L
KETAMINE
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Expert Panel on Drug Driving:

Roger Brimblecombe, Colin Forfar, A. Robert Forrest, Eilish
Gilvarry, Judith Morgan, M. David Osselton, Lily Read,
David Taylor, and Atholl Johnston
REFERENCES
https://www.gov.uk/government/publications/driving-underthe-influence-of-drugs--2
http://blogs.bmj.com/bmj/2013/03/27/kim-wolff-drugdriving-limits/
ACKNOWLEDGEMENTS
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THANK YOU
ANY QUESTIONS
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