Deaths from Opioid Overdosing: Implications of Coroners’ Inquest Reports 2008–2012 and Annual Rise in Opioid Prescription Rates: A Population-Based Cohort Study
Deaths from Opioid Overdosing: Implications of Coroners' Inquest Reports 2008-2012 and Annual Rise in Opioid Prescription Rates: A Population-Based Cohort Study
Edward A. Shipton 0 1
0 J. A. Williman Department of Population Health, University of Otago , Christchurch , New Zealand
1 E. E. Shipton A. J. Shipton E. A. Shipton (&) Department of Anaesthesia, University of Otago , Christchurch , New Zealand
Introduction: In the late 1990s multiple physicians and advocacy organizations promoted increased use of opioids for the treatment of acute, chronic and cancer pain. There has been an exponential growth in opioid prescribing in the last 20 years in the United States of America, in Australia, and in other developed Western countries. There are negative consequences associated with the liberal use of opioids. The primary aim of this population-based cohort study is to investigate the opioid-related death rate in New Zealand between 1 January 2008 and 31 December 2012. The secondary aims of this cohort study are: (1) to compare the opioid-related death rate per population in New Zealand in 2001/2002 with that between 2011/2012; (2) to investigate the number of opioid prescriptions in New Zealand between 2001 and 2012; (3) to compare the opioid-related death rate per population in New Zealand
between 2001 and 2012 with the number of
opioid prescriptions in New Zealand between
2001 and 2012.
Methods: Permission to access records from the
Coronial Services Office in Wellington for
2008–2012 was acquired. Permission to access
records for prescriptions containing opioids
(dose and formulation) was obtained from the
Results: The rate of opioid-related deaths in
New Zealand has increased by 33% from 2001 to
2012. More than half of the opioid-related deaths
between 2008 and 2012 were unintentional
opioid overdoses. Opioid analgesic deaths were
most likely due to methadone, morphine and
codeine prescribed by healthcare professionals.
That 179 of these opioid-related deaths between
2008 and 2012 were unintentional opioid
overdoses, and thus could have been avoided, is
tragic. This study shows that there was a steady
annual increases in opioid prescriptions in New
Zealand from 2001 to 2012. This rise in opioid
analgesic deaths was associated with the
increases in the numbers of opioid prescriptions.
Conclusion: A multifaceted national public
health approach is needed to bring together the
various stakeholders involved with pain
management, opioid dependence, opioid
availability and opioid diversion. There needs to be a
targeted approach to educate current and future
medical practitioners regarding the appropriate
use of opioid prescriptions for the management
of pain, as well as a strengthening of primary,
secondary and tertiary resources to support
medical practitioners managing their patients
who suffer with pain.
Opioids are used as primary analgesics to relieve
acute, chronic and cancer pain. Historically,
opioid analgesics were predominantly
prescribed for acute pain and cancer-related pain
. In the 1980s international attention started
focusing on the undertreatment of chronic
pain. In 1986, Dr. Russel Portenoy stated that
opioids were a ‘‘safe, salutary and more
humane’’ treatment for patients with
intractable non-malignant pain . It was
further asserted that the rate of addiction in
chronic pain patients treated with opioids was
low and that it was therefore unethical to
restrict access to opioids necessary to relieve
suffering due to chronic non-cancer pain [2, 3].
The potential adverse effects of chronic opioid
use were played down with an overriding belief
that opioids were safe, with no dosing threshold
in the legitimate pain sufferer [1, 2]. These
assertions, together with the availability of new
synthetic opioids (e.g. oxycodone), the intense
marketing strategies adopted by manufacturers
and increased patient demand, have resulted in
an exponential growth in opioid prescribing in
the last 20 years [4, 5]. Between 1992 and 2012,
opioid-dispensing episodes have increased by
15-fold (500,000 to 7.5 million) in Australia .
However, recent evidence-based research
brings into question whether opioids are indeed
effective against long-term chronic pain .
Only some patients with chronic non-cancer
pain experience clinically significant pain relief
with long-term opioid use and, in general, there
is inconclusive evidence that opioid therapy
improves quality of life and functioning in
these patients . In addition, opioids can
create suffering with the risks of tolerance,
dependence, abuse and opioid-related mortality
and morbidity [1, 8]. No objective standard
exists for levels of opioid consumption, and the
rates of opioid prescription and use cannot be
judged as adequate or excessive as there is no
recognized baseline for a particular population
. Yet there appears to be higher rates of
addiction and misuse with respect to opioid use
in chronic pain treatment than previously
]. There is a parallel relationship
between the availability of prescription opioid
analgesics through legitimate pharmacy
channels and the diversion and abuse of these drugs
and associated adverse outcomes [
Nonmedical use of prescription pain relievers in the
USA is increasing, and there are comparable
rises in hospital admissions for misuse [
In the USA, there is a rapidly emerging public
health epidemic of prescription opioid-related
mortality in patients with chronic non-cancer
pain; more than 100,000 people have died from
an unintentional overdose since policies
changed in the late 1990s, and more than 16,000
people are dying from opioid-related causes
]. Opioid prescription drug
overdose has surpassed motor vehicle collision
as the leading cause of unintentional
injury-related death in the USA [
Deaths due to accidental poisoning
(pharmaceutical opioids and illicit substances
combined) in Australia increased from 151 in 2002
to 266 in 2011 . The use of opioids is under
increasing scrutiny, and many governmental
agencies are focusing on strategies to manage
what is seen to be an increasing epidemic of
opioid use and abuse [
]. The trends in
long-term opioid use and the problem of
opioid-related mortality seen in the USA and Australia
may not be reflected in New Zealand because of
differences in healthcare systems, funding
models and prescribing guidelines. In New
Zealand, only deaths from opioid poisonings
from 1 January 2001 to 31 December 2002 have
previously been published, motivating the need
for a fresh audit of the data [
The primary aim of this population-based
cohort study was to investigate the
opioid-related death rate in New Zealand between 1
January 2008 and 31 December 2012. The
secondary aims were: (1) to compare the
opioid-related death rate per population in New
Zealand in 2001/2002 with that in 2011/2012;
(2) to investigate the number of opioid
prescriptions in New Zealand between 2001 and
2012; (3) to compare the opioid-related death
rate per population in NZ between 2001 and
2012 with the number of opioid prescription in
New Zealand between 2001 and 2012.
For this study, permission to access records from
the Coronial Services Office in Wellington was
acquired. Data from the Coroner (2008–2012
only) was taken from the year of notification of
death and filtered for primary contribution.
Deaths from opioid poisonings or overdoses in
New Zealand from 1 January 2008 to 31
December 2012 were identified. A manual
review of the coding of all cases in the dataset
was undertaken to confirm that the cases were
of relevance. The following incidents were
excluded from the data set: cases which
involved anaphylaxis; fatalities occurring due to
complications during medical treatment, such
as the administration of anesthetic during
A substance was considered to have made a
primary contribution to a death where drug
toxicity was noted within the cause of death or
the primary object field in the National
Coronial Information System code set, or where
aspiration of gastric contents was noted in the
cause of death and drug toxicity was noted
anywhere in the cause of death. Additionally, if
the death was noted as being contributed to by
a combination of multiple coded drugs (such as
‘mixed drug toxicity’ or ‘multiple drug
overdose’), the drugs that were part of the ‘multiple
drug’ combination were recorded. The
determination of the ‘‘intent’’ of the deceased person
was subject to the individual determination of
the Coroner investigating the fatality. The
medical cause of death was based on the
Forensic Pathologist’s individual opinion [
The number of opioid-related deaths were
summarized by year, gender, age and type of
opioid. Mortality rates per million person-years
were calculated by age and gender with 95%
Poisson confidence intervals (CI) using, as the
denominator, estimates of the New Zealand
resident population provided by Statistics New
]. Rate ratios with 95% mid-p exact
confidence intervals were used to compare
differences in mortality rates between females and
males. The association between opioid
prescriptions (per 100,000) and opioid-related
deaths from 2001 to 2012 was estimated using a
linear regression model. Analysis was performed
using the R statistical package (R Foundation for
Statistical Computing, Vienna, Austria).
Permission to access records for prescriptions
containing opioids (dose and formulation) was
obtained from the Pharmaceutical Collection.
The Pharmaceutical Collection contains claim
and payment information from pharmacists for
subsidized dispensing processed by the Sector
Services General Transaction Processing System.
It is jointly owned by the Ministry of Health
and the Pharmaceutical Management Agency
(PHARMAC) in New Zealand [
]. Data were
accessed to determine the sum of the opioid
prescriptions between 2001 and 2012 only.
Compliance with Ethics Guidelines
This article is based on previously conducted
studies and does not involve any new studies of
human or animal subjects performed by any of
the authors. Ethical approval from the
University of Otago’s Human Ethics Committee was
obtained (Number HD15/036), and the
appropriate statistical analyses were performed.
From 2008 to 2012, a total of 325 deaths were
primarily ascribed to opioid use (Table 1). Males
had a higher rate of death than females (16.58
vs. 13.43 per 1,000,000 person-years; rate ratio
1.23; 95% Cl 0.99–1.54; p = 0.059).The highest
incidence rate per 1,000,000 person years was in
the 40–49 year age group as shown in Table 2.
During this same period, there were 179
unintentional opioid overdoses, 110 intentional
opioid overdoses and 37 opioid deaths from
undetermined or other specified intent. The
number of opioid deaths per year and type of
opioid (2008–2012) is shown in Table 3. The
opioids methadone, morphine, codeine were
the most frequent causes of death.
There was an increase in prescriptions issued
in New Zealand for each type of opioid between
2001 and 2012 (see Fig. 1). Two types of opioid
prescriptions were not included in this Fig. 1
due to the small total number of prescriptions
issued between 2001 and 2012. These were
buprenorphine hydrochloride (total of 88
prescriptions) and pentazocine (total of 815
prescriptions). Prescriptions for pethidine fell from
21,696 in 2001 to 8442 in 2012, while
prescriptions for dextropropoxyphene declined
after 2007 to nil in 2012.
The total number of prescription opioids
rose from 686,063 in 2001 to 1,673,640 in 2012.
Codeine and codeine plus paracetamol
prescriptions increased from 225,723 in 2001 to
789,214 in 2012 (an increase of 250%).
Tramadol prescriptions increased from 142,059 in
2010 (when first subsidized in New Zealand) to
331,126 in 2012 (an increase of 133% 2 years
Table 1 Frequency of opioid deaths per year (2008–2012)
deaths by resident
CI Confidence interval
Rate per 1,000,000 (95% CI)
later). Morphine prescriptions increased from
136,619 in 2001 to 190,816 in 2012 (an increase
of 40%). The dispensing of oxycodone
prescriptions increased from 2836 in 2005 (when
introduced into New Zealand) to 180,830 in
2012 (an increase of 6276% over a 7-year
period). The number of methadone prescriptions
increased from 49,951 in 2001 to 103,477 in
2012 (an increase of 107%). The number of
fentanyl prescriptions increased from 217 in
2004 to 28,623 in 2012 (an increase of
The number of opioid deaths by primary
opioid contribution (2001–2012) versus the
total number of opioid prescriptions in New
Zealand (2001–2012) is shown in Fig. 2.
Between 2001 and 2012 there was an
approximate linear relationship between the number of
opioid prescriptions and the number of deaths
by primary opioid contribution, such that an
increase of 100,000 opioid prescriptions was
associated with an additional 2.4 (95% CI
1.6–3.2, p\0.001) deaths. Much of the increase
in deaths occurred between 2002 and 2008,
with only weak evidence of a linear increase by
year from 2008 and 2012 (p = 0.07).
Opioid-Related Death Rate and Characteristics
In New Zealand, the rate of opioid-related
deaths in 2012 was 1.6 per 100,000. This is
considerably less than the corresponding rate of
3.6 per 100,000 in Victoria, Australia in 2012
and 7.9 per 100,000 in 2013 in the USA [
However, there is no room for complacency.
The rate of opioid deaths in New Zealand is
increasing at a significant rate. In 2001–2002,
the rate of opioid-related deaths was 1.17 per
100,000 ; this rose to 1.60 per 100,000 in
2011–2012, reflecting a 33% increase in the
10-year interim period.
The number of deaths in New Zealand
ascribed to be primarily due to use during the
period 2008–2012 is 325. Of these, 110 deaths
(34%) were from intentional opioid overdoses,
and 179 (55%) were from unintentional opioid
Total number of deaths over the entire study period Rate per 1,000,000 (95% CI)
overdoses. The high number of unintentional
overdoses is tragic as these are potentially
avoidable. These data emphasize the need for
educating both prescribers and the public alike.
Similar to other countries, the rate of opioid
poisoning deaths in New Zealand is marginally
higher among men [
]. The highest
incidence rate per 1,000,000 person-years was in the
40–49 year age group, possibly due to a cohort
effect arising from the aging baby-boomer
generation. In addition, age and physical state
could affect one’s capacity to metabolize
In New Zealand from 2008 to 2012,
opioid-related deaths were most frequently
attributed to the opoids methadone, morphine,
codeine and oxycodone. Clearly, the
availability of drugs has an influence on the level of
abuse. New Zealand was successful in the
restriction of heroin supply in the 1970s and
1980s, probably as a result of unique factors,
such as island isolation, a small market, and
effective law enforcement and low corruption
]. Our study shows a relatively high use
of methadone and morphine relative to illicit
heroin use, similar to results of other studies
undertaken in New Zealand [
Pharmaceutical Management Agency (PHARMAC)
in New Zealand regulates funding for drugs
according to clinical effectiveness and
cost-effectiveness, health needs, budget impact, direct
cost to users and availability of alternative
treatments . The actions of PHARMAC have
influenced the number of opioid-related deaths
during the period 2008–2012. Slow-release
oxycodone (OxyContin) became available in
2005, and since then, dispensing rates have
There were a significant number of deaths
due to dextropropoxyphene in 2001–2002.
Dextropropoxyphene was discontinued in New
Zealand in December 2009; this resulted in
limited access to this drug and a decrease in the
number of deaths associated with its use. Access
and use of opioids is established not only by
physical availability and practical accessibility,
but also by affordability [
]. Tramadol use in
New Zealand increased rapidly after it became
fully funded by PHARMAC in June 2010 [
The results of this study show that from 2001
to 2012 there appears to be a linear relationship
between the number of deaths due to opioid use
and the prescription rates. A similar trend of
increasing opioid consumption accompanied
by increasing rates of misuse and overdose have
been observed in Australia and the USA [
Opioid Prescription Rates and Characteristics
In New Zealand from 2011 to 2012 (2-year
period) there were 3,233,946 prescriptions
dispensed for opioid medicines, representing
36,583 prescriptions per 100,000 people. In
comparison, there were 13,905,258
prescriptions dispensed for opioid medicines in
Australia in the period 2013–2014 (2 years),
representing 55,126 prescriptions per 100,000
]. In the international framework,
opioid consumption in New Zealand is less than
that in Canada, the USA, Australia and the UK,
This study shows an exponential increase in
total opioid prescriptions in New Zealand from
2001 to 2012 (686,063 in 2001 to 1,673,640 in
2012), driven mainly by an increase in codeine
prescriptions. In other countries, opioid use has
doubled over a similar period, particularly in
high-income countries, such as those of North
America, western and central Europe and
]. A recent study has shown this
trend is continuing beyond 2012, with an
26.18 (17.78, 37.15)
11.82 (8.13, 16.60)
2.26 (1.17, 3.96)
3.79 (2.17, 6.16)
0.00 (0.00, 237.99)
average of 16.4/1000 people in New Zealand
receiving a strong opioid in 2015, a marginal
increase from 2011 (14.3/1000) [
dispensing rates of both strong and weak opioids
in New Zealand have been shown to be higher
for people of Caucasian origin (as compared to
Ma¯ori, Pacific or Asian ethnicities) and higher
for women and people aged C 80 years [
Nearly half of all New Zealanders who received a
strong opioid in 2015 had recently attended a
public hospital as an inpatient or outpatient,
suggesting many of these prescriptions are
generated in the hospital setting [
The mortality rate per prescription for
methadone, morphine and codeine has not
changed markedly (Table 4). However, the
number of prescriptions has increased, and so
have the number of deaths. These data
highlight the increase in deaths according to
increased prescription of existing drugs and
introduction of new drugs (Table 4).
Findings for Specific Drugs
Methadone accounts for the highest number of
opioid-related deaths in New Zealand.
Methadone has been used as part of opioid
substitution treatment (OST) for opioid dependence in
New Zealand since the 1970s [
increasing total number of methadone prescriptions is
likely to be related to the steadily increasing
number of OST patients in New Zealand since
]. There were more than 5000 OST
patients in 2012, and an increasing proportion
of these patients were being managed in
primary care [
]. Methadone constitutes a
significant proportion of street opioid supply in New
Zealand, and since methadone is primarily
prescribed for OST, this may suggest insufficient
dispensing controls [
prescription has been found to significantly decrease
intravenous heroin use, which could contribute
to the low rate of heroin overdoses in New
]. Buprenorphine became subsidized
by PHARMAC in July 2012 and has provided an
alternative OST medication to methadone [
This is a positive step as buprenorphine has a
reduced potential risk of overdose compared to
]. It has been suggested that
buprenorphine should be considered as the
drug of first choice by clinicians treating
patients with opioid dependence, especially
polydrug users .
Codeine-related deaths in New Zealand rose
markedly from 1.5 per million people in
2001/2002 to 4.0 per million in 2012. In
Australia, codeine-related deaths increased from 3.5
per million in 2000 to 8.7 per million in 2009,
and deaths from accidental overdoses were
found to be more common (48.8%) than
intentional deaths (34.7%) [
]. Severe harmful
events have been described with codeine use,
especially from the consumption of high doses
of combination products, such as
codeine/paracetamol and codeine/ibuprofen
]. About 5% of the white population are
ultra-rapid metabolizers, meaning that there is a
higher conversion to morphine with an
increased risk of adverse events, such as
respiratory depression and fatal overdose [
Codeine has been implicated in the
postoperative deaths of children . Research in
Australia and overseas has shown that those
individuals who misuse codeine tend to be
better educated and more often employed
and tend not to use illicit drugs [
Australia from 1 February 2018 onwards, analgesics
containing codeine will be available only on
Codeine use in New Zealand is difficult to
quantify, as it is relatively inexpensive and
low-dose codeine can be obtained in
combination with paracetamol over-the-counter (OTC)
without a prescription. New Zealand would
need to consider its own figures in light of the
Australian data and act accordingly.
Oxycodone made its appearance in New Zealand
in 2005 and was promoted as an alternative to
morphine. It was preceded and supported by a
driven and costly advertising campaign that
resulted in the rapid annual rise in oxycodone
]. It was marketed as having a low
potential for misuse, which was subsequently
shown to be incorrect [
]. The exponential
increase in the number of prescriptions of
slow-release oxycodone since its introduction has
been matched by an increase in
oxycodone-related deaths. The overall number of
oxycodone-related deaths in New Zealand and
Australia is currently relatively low. The
proportion of frequent injecting-drug users in New
Zealand who had used oxycodone at any
time increased from 21% in 2008 to 54% in 2012
Tramadol is a multimodal analgesic, with only a
weak mu opioid effect from its metabolites. It has
only been fully funded in New Zealand since June
2010. When used appropriately, tramadol
provides important medical benefits. Evidence
appears to indicate that tramadol is associated
with a low potential for misuse, abuse and
]. However, it can have serious
health consequences when taken without
medical supervision, in larger amounts than prescribed
or in combination with illicit drugs, alcohol, or
other prescription or OTC medications [
From February 2011 fentanyl patches became
fully funded in New Zealand without special
]. Rates of fentanyl use are
currently low, but are increasing. Fentanyl use
increased from 217 prescriptions in 2004 to
28,623 in 2012, which reflects a 132-fold
increase. This increase is probably due to an
increasing supply of synthetic opioids and the
use of fentanyl patches in residential homes to
treat chronic non-malignant pain (CNMP). The
risk of fatality with fentanyl patches arises when
they are given to opioid-na¨ıve patients [
New Zealand there were only three deaths from
fentanyl in 2011–2012.
Preventative Measures to Limit
Overprescribing and Mitigate Risk
Mitigation of risk is important to encourage
safer prescribing of opioids and to prevent
opioid abuse, dependence and death.
Appropriate evaluation, documentation, screening
and risk stratification are indicated, starting
from the initiation of the opioid therapy and
continuing through to its discontinuation .
There are a wide range of social, psychological,
and physical treatment options available for
patients with CNMP. Combinations of
non-opioid analgesics and
non-pharmacological treatments are the mainstay of treatment for
CNMP. Opioids should be titrated slowly, with
frequent dispensing and close monitoring for
signs of misuse [
]. If opioid therapy is deemed
to be necessary, patients should be prescribed
weaker opioids, such as tramadol, before being
started on the stronger ones. Codeine should
not be prescribed to breastfeeding mothers due
to the risks of toxicity in rapid metabolizers
]. Fentanyl should only be prescribed to
opioid-tolerant patients [
]. Methadone has a
long and variable half-life and should not be
used for acute pain or breakthrough pain [
The opioid should be tapered if the patient’s
pain remains severe despite an adequate trial of
opioid therapy [
General practitioners need to be made aware
of the predictors of opioid overdose, which
include a mean daily oral morphine-equivalent
dose of [100 mg per day, mental health
disorders, concomitant use of benzodiazepines and
antidepressants and substance use disorders
]. Care needs to be taken when
prescribing opioids for adolescents, who are at
high risk of opioid overdose, misuse and
addiction . In the elderly, overdose can be
minimized through lower initial doses, slower
titration, benzodiazepine tapering and careful
patient education [
Other key prevention strategies include
educating the general population on the use of
tamper-resistant formulations and the danger of
combining opioids (such as oxycodone and
buprenorphine) with low-dose naloxone,
expanding availability and community access
to naloxone and carrying out prescription
monitoring programmes [
evidence on extended-release naltrexone is more
encouraging as this drug is not subject to misuse
or diversion . Nation-wide prescription
monitoring programmes should be
implemented to facilitate early detection. In
New Zealand more use needs to be made of the
information on prescribing collected by the
Pharmaceutical Collection. Public health
agencies, medical examiners and coroners and law
enforcement agencies should work
collaboratively to improve the detection of and response
to drug overdoses related to illicit opioids [
Limitations of the Study
The dataset from the Coroner does not claim to
be representative of all relevant cases within the
time period specified. This may have been due
to missing data and occasional processing and
coding errors. The Query Design Search Screen
was used to identify cases of relevance. There
were some limitations as coded fields were not
completed until closure of the case and the
extent of the information contained in the text
reports varied. The determination of the
‘‘intent’’ of the deceased person was subject to the
individual determination of the Coroner
investigating the fatality. The medical cause of death
was based on the Forensic Pathologist’s
individual opinion. Another limitation of this and
most studies is the lack of distinction between
death due to prescription-related opioids and
that due to illicit opioids.
Dr. Portenay, who originally promoted the
liberal use of opioids in the 1980s, has
subsequently stated that in the light of further
research it would appear ‘‘that the benefits of
opioids had been overstated and the risks
glossed over’’ [
]. There is ample evidence of an
emerging public health problem in New
Zealand, related to inappropriate opioid prescribing
From 2008 to 2012, a total of 325 deaths
were primarily ascribed to opioid use, with a
higher rate of death among males than among
females: 16.58 vs. 13.43 per 1,000,000
person-years (rate ratio 1.23; 95% Cl 0.99–1.54;
p = 0.059). One of the predictors of opioid
overdose is the male sex [
2001–2002, the rate of opioid-related deaths
was 1.17 per 100,000 . This has risen to
1.60 per 100,000 in 2012, reflecting a 33%
increase in the 10-year interim period. This is
in line with the situation in other First World
The first exposure of most opioid abusers to
the opioid began with a legitimate prescription
for pain [
]. A sharp increase in the
prescription of opioids has been associated with
increases in opioid overdose [
]. The results of
the present study confirm this trend. There have
been incremental annual increases in opioid
prescriptions in New Zealand from 2001 to
2012, with a more than doubling of the total
number of prescriptions issued from 2001 to
2012. This rising trend in opioid prescription
rate is associated with a corresponding rise in
deaths from opioid analgesics. The fact that
more than half (179) of the opioid-related
deaths between 2008 and 2012 were
unintentional opioid overdoses and could have been
avoided is tragic. Opioid analgesic deaths were
most likely due to methadone, morphine and
codeine prescribed by healthcare professionals.
The significant rise in prescriptions of
oxycodone, codeine and fentanyl-related products
are of growing concern. This concern can be
addressed by ensuring that providers perform
risk assessments, are perceptive of medication
risks, avoid excessive dependence on opioids
and adequately educate and monitor patients
A multifaceted national public health
approach is needed to bring together the
various stakeholders involved with pain
management, opioid dependence, opioid availability
and opioid diversion. There needs to be a
targeted approach to educate current and future
medical practitioners in the appropriate use of
opioid prescriptions for the management of
pain, as well as a strengthening of primary,
secondary and tertiary resources to support
medical practitioners managing their patients
suffering with pain.
No funding or sponsorship was received for this
study or publication of this article. All named
authors meet the International Committee of
Medical Journal Editors (ICMJE) criteria for
authorship for this manuscript, take
responsibility for the integrity of the work as a whole,
and have given final approval for the version to
Disclosures. Elspeth E. Shipton, Ashleigh J.
Shipton, Jonathan A. Williman and Edward A.
Shipton have nothing to disclose.
Compliance with Ethics Guidelines. This
article is based on previously conducted studies
and does not involve any new studies of human
or animal subjects performed by any of the
authors. Ethical approval from the University of
Otago’s Human Ethics Committee was obtained
(Number HD15/036), and the appropriate
statistical analyses were performed.
Data Availability. The datasets analyzed
during the current study are available from the
corresponding author on reasonable request.
Open Access. This article is distributed
under the terms of the Creative Commons
Attribution-Non Commercial 4.0 International
by-nc/4.0/), which permits any
noncommercial use, distribution, and reproduction in any
medium, provided you give appropriate credit
to the original author(s) and the source, provide
a link to the Creative Commons license, and
indicate if changes were made.
Cheatle MD . Prescription opioid misuse, abuse, morbidity, and mortality: balancing effective pain management and safety . Pain Med . 2015 ; 16 [Suppl 1]: S3 - 8 .
Portenoy RK , Foley KM . Chronic use of opioid analgesics in non-malignant pain: report of 38 cases . Pain. 1986 ; 25 ( 2 ): 171 - 86 .
Porter J , Jick H . Addiction rare in patients treated with narcotics . N Engl J Med . 1980 ; 302 ( 2 ): 123 .
Kanouse AB , Compton P. The epidemic of prescription opioid abuse, the subsequent rising 5 .
Manchikanti L , Abdi S , Atluri S , Balog CC , Benyamin RM , Boswell MV , et al. American Society of Interventional Pain Physicians (ASIPP) guidelines for responsible opioid prescribing in chronic noncancer pain: part I-evidence assessment . Pain Phys . 2012 ; 15 [3 Suppl]: S1 - 65 .
Cochrane Database Syst Rev . 2010 ; 1 : Cd006605 .
Stein C. Opioid receptors . Annu Rev 2016 ; 67 : 433 - 51 .
Seya MJ , Gelders SF , Achara OU , Milani B , Scholten WK . A first comparison between the consumption of and the need for opioid analgesics at country, regional, and global levels . J Pain Palliat Care Pharmacother . 2011 ; 25 ( 1 ): 6 - 18 .
10. Dart RC , Severtson SG , Bucher-Bartelson B . Trends in opioid analgesic abuse and mortality in the United States . N Engl J Med . 2015 ; 372 ( 16 ): 1573 - 4 .
11. Okie S. A flood of opioids, a rising tide of deaths . N Engl J Med . 2010 ; 363 ( 21 ): 1981 - 5 .
12. Centers for Disease Control and Prevention. Vital signs: overdoses of prescription opioid pain relievers and other drugs among women-United States, 1999 - 2010 . MMWR Morb Mortal Wkly Rep . 2013 ; 62 ( 26 ): 537 - 42 .
13. Jones CM , Mack KA , Paulozzi LJ . Pharmaceutical overdose deaths , United States , 2010 . JAMA. 2013 ; 309 ( 7 ): 657 - 9 .
14. Warner M , Chen LH , Makuc DM , Anderson RN , Minin˜o AM . Drug poisoning deaths in the United States, 1980 - 2008 . NCHS Data Brief . 2011 ; 81 : 1 - 8 .
15. Reith D , Fountain J , Tilyard M. Opioid poisoning deaths in New Zealand ( 2001 -2002 ). N Z Med J. 2005 ; 118 ( 1209 ): U1293 .
16. National Coronial Information System (NCIS) . CR15-19 . 2007 - 2015 . Southbank, Australia: NCIS
17. Statistics New Zealand. Population statistics. http:// www.stats.govt.nz/browse_for_stats/population. aspx. Accessed 18 Mar 2017 .
18. Ministry of Health. http://www.health.govt.nz/nzhealth-statistics/ national-collections-and-surveys/ collections/pharmaceutical-collection . Accessed 2 Apr 2017 .
19. Monheit B , Pietrzak D , Hocking S. Prescription drug abuse-a timely update . Aust Fam Physician . 2016 ; 45 ( 12 ): 862 - 6 .
20. Rudd RA , Aleshire N , Zibbell JE , Gladden RM . Increases in drug and opioid overdose deathsUnited States, 2000 - 2014 . MMWR Morb Mortal Wkly Rep . 2016 ; 64 ( 50 -51): 1378 - 82 .
21. Berecki-Gisolf J , Hassani-Mahmooei B , Clapperton A , McClure R . Prescription opioid dispensing and prescription opioid poisoning: population data from Victoria, Australia 2006 to 2013 . Aust N Z J Public Health . 2017 ; 41 ( 1 ): 85 - 91 .
22. McMinn J . Opioid dependence, a life-threatening condition, is preventable . N Z Med J. 2014 ; 127 ( 1397 ): 5 .
23. Robinson G , Judson G , Loan R , Bevin T , O'Connor P. Patterns of prescription drug misuse presenting to provincial drug clinics . N Z Med J (Online) . 2011 ; 124 ( 1336 ): 62 - 7 .
24. PHARMAC . About PHARMAC. https://www. pharmac.govt.nz/about/. Accessed 12 Apr 2017 .
25. Berterame S , Erthal J , Thomas J , Fellner S , Vosse B , Clare P , et al. Use of and barriers to access to opioid analgesics: a worldwide, regional, and national study . Lancet . 2016 ; 387 ( 10028 ): 1644 - 56 .
26. Best Practice Journal . Snippets: Safer prescribing of tramadol 2010 . http://www.bpac.org.nz/BPJ/2010/ June/snippets.aspx. Accessed 12 Apr 2017 .
27. Weisberg DF , Becker WC , Fiellin DA , Stannard C . Prescription opioid misuse in the United States and the United Kingdom: cautionary lessons . Int J Drug Policy . 2014 ; 25 ( 6 ): 1124 - 30 .
28. Australian Commission on Safety and Quality in Health Care. Australian atlas of healthcare variation. chapter 5.1: Opioid medicines dispensing . https:// www.safetyandquality.gov.au/wp-content/uploads/ 2015/11/SAQ201_06_ Chapter5_v12_FILM_tagged_ merged_5-1 .pdf. Accessed 2 Apr 2017 .
29. University of Wisconsin-Madison Pain & Policy Studies Group. Opioid consumption data . http:// www.painpolicy.wisc.edu/opioid-consumption -data. Accessed 2 Apr 2017 .
30. Davis A , Davis K , Gerard C , Goyal S , Jackson G , James C , et al. Opioid rain: opioid prescribing is growing and practice is diverging . N Z Med J. 2016 ; 129 ( 1440 ): 11 - 7 .
31. Deering D , Sellman JD , Adamson S. Opioid substitution treatment in New Zealand: a 40 year perspective . N Z Med J. 2014 ; 127 ( 1397 ): 57 - 66 .
32. Pirnay S , Borron SW , Giudicelli CP , Tourneau J , Baud FJ , Ricordel I. A critical review of the causes of death among post-mortem toxicological investigations: analysis of 34 buprenorphine-associated and 35 methadone-associated deaths . Addiction . 2004 ; 99 ( 8 ): 978 - 88 .
33. Mattick RP , Breen C , Kimber J , Davoli M. Buprenorphine maintenance versus placebo or methadone maintenance for opioid dependence . Cochrane Database Syst Rev . 2014 ; 2 : Cd002207 .
34. Roxburgh A , Hall WD , Burns L , Pilgrim J , Saar E , Nielsen S , et al. Trends and characteristics of accidental and intentional codeine overdose deaths in Australia . Med J Aust. 2015 ; 203 ( 7 ): 299 .
35. Nielsen S , Bruno R , Murnion B , Dunlop A , Degenhardt L , Demirkol A , et al. Treating codeine dependence with buprenorphine: dose requirements and induction outcomes from a retrospective case series in New South Wales, Australia . Drug Alcohol Rev . 2015 ; 35 : 70 - 75 .
36. Chidambaran V , Sadhasivam S , Mahmoud M. Codeine and opioid metabolism: implications and alternatives for pediatric pain management . Curr Opin Anaesthesiol . 2017 ; 30 ( 3 ): 349 - 56 .
37. Tverdohleb T , Dinc B , Knezevic I , Candido KD , Knezevic NN . The role of cytochrome P450 pharmacogenomics in chronic non-cancer pain patients . Expert Opin Drug Metab Toxicol . 2016 ; 12 ( 11 ) 1303 - 11 .
38. Nielsen S , Murnion B , Dunlop A , Degenhardt L , Demirkol A , Muhleisen P , et al. Comparing treatment-seeking codeine users and strong opioid users: findings from a novel case series . Drug Alcohol Rev . 2015 ; 34 ( 3 ): 304 - 11 .
39. Therapeutic Goods Administration. Codeine-containing medicines: Department of Health, Australian Government . http://www.tga.gov.au/. Accessed 12 Apr 2017 .
40. Dyer O. Kentucky seeks $1bn from Purdue Pharma for misrepresenting addictive potential of oxycodone . BMJ . 2014 ; 349 : g6605 .
41. Wilkins C , Jawalkar P , Parker K. Recent trends in illegal drug use in New Zealand, 2006 -2012 : findings from the 2006 , 2007 , 2008 , 2009 , 2010 , 2011 and 2012 Illicit Drug Monitoring System (IDMS) 2013 . http://www.whariki.ac.nz/massey/learning/ departments/centres-research/shore/projects/illicitdrug-monitoring-system. cfm. Accessed 2 Apr 2017 .
42. Radbruch L , Glaeske G , Grond S , Mu¨nchberg F , Scherbaum N , Storz E , et al. Topical review on the abuse and misuse potential of tramadol and tilidine in Germany . Subst Abuse . 2013 ; 34 ( 3 ): 313 - 20 .
43. Bush DM . Emergency department visits for drug misuse or abuse involving the pain medication tramadol . The CBHSQ report. Rockville: Substance Abuse and Mental Health Services Administration (US) ; 2013 .
44. Best Practice Advocacy Centre Inc (BPAC). Snippets: fentanyl patches . Best Practice Journal 2010 . http:// www.bpac.org.nz/BPJ/2010/December/snippets. aspx. Accessed 12 Apr 2017 .
45. Taghogho Agarin M , Andrea Trescot M , Aniefiok Agarin M. Reducing opioid analgesic deaths in America: what health providers can do . Pain Phys . 2015 ; 18 : E307 - 22 .
46. Kahan M , Wilson L , Mailis-Gagnon A , Srivastava A . Canadian guideline for safe and effective use of opioids for chronic noncancer pain: clinical summary for family physicians . Part 2 : special populations. Can Fam Physician . 2011 ; 57 ( 11 ): 1269 - 76 , e419 - 28 .
47. Al-Adhami N , Whitfield K , North A . Changing prescribing culture-a focus on codeine postpartum . Arch Dis Child . 2016 ; 101 ( 9 ): e2 .
48. Warner EA . Opioids for the treatment of chronic noncancer pain . Am J Med . 2012 ; 125 ( 12 ): 1155 - 61 .
49. Faculty of Pain Medicine Australian and New Zealand College of Anaesthetists. Recommendations regarding the use of opioid analgesics in patients with chronic non-cancer pain-position statement . http://www.fpm.anzca.edu.au/. 2015 .
50. Connery HS . Medication-assisted treatment of opioid use disorder: review of the evidence and future directions . Harvard Rev Psychiatry . 2015 ; 23 ( 2 ): 63 - 75 .
51. Catan T , Perez E. A pain-drug champion has second thoughts . Wall Street J . 2012 ; December 17 . http:// www.wsj. com/articles/SB100014241278873244783 04578173342657044604. Accessed 12 Apr 2017 .
52. Shah A , Hayes CJ , Martin BC . Characteristics of initial prescription episodes and likelihood of long-term opioid use-United States, 2006 - 2015 . MMWR Morb Mortal Wkly Rep . 2017 ; 66 ( 10 ): 265 - 9 .
53. Frenk SM , Porter KS , Paulozzi LJ . Prescription opioid analgesic use among adults: united States, 1999 - 2012 . NCHS Data Brief . 2015 ; 189 : 1 - 8 .
54. Lamvu G , Feranec J , Blanton E. Perioperative pain management: an update for obstetrician-gynecologists . Am J Obstetr Gynecol . 2017 . doi: 10 .1016/j. ajog. 2017 . 06 .021