Research focus

NCETA are investigating prescribed opioid use resulting from compensable work-related injuries in South Australia. Participants are South Australians aged 16 years and over who, between January 2003 and December 2012, submitted a WorkCover SA workers compensation claim and/or were dispensed S8 prescribed opioids. Approximately 10,000 persons acquired a work-related injury and received S8 prescribed opioids during the study period.

What are we doing?

NCETA are investigating prescribed opioid use resulting from compensable work-related injuries in South Australia. Participants are South Australians aged 16 years and over who, between January 2003 and December 2012, submitted a WorkCover SA workers compensation claim and/or were dispensed S8 prescribed opioids. Approximately 10,000 persons acquired a work-related injury and received S8 prescribed opioids during the study period.

In order to determine the nature, extent and impact of prescribed opioid use on worker well-being after a work-related injury, NCETA is tracking participants, their claim history, and opioid medication regime (dose levels, drug types, duration, number of prescribers and pharmacists) in a 10 year retrospective observational study.

The study entails linking the following SA government administration data:

1. work-related accidents and injuries (Work-Safe Health and Safety Tabulator)
2. dispensed S8 prescribed opioids (Drugs of Dependence Unit, SA Health)
3. Emergency Department presentations (SA Emergency Department Data Collection), and
4. public hospital admissions (SA Admitted Patient Activity Data Standards).

These four datasets will be linked by SANT Datalink. NCETA will subsequently integrate the four de-identified datasets for analyses purposes.

WorkCover SA data provides a record of all work-related incidents and injuries in SA. It includes workers defined as “a person working within employment relationship”.

Drugs of Dependence data is a precise account of prescribed S8 opioids dispensed in SA. This data is collected under the auspices of the South Australian government’s Controlled Substances legislation.

Measures of interest are demographics (age, gender, locality, new worker, industry division, occupation and work type); injury (date, nature, mechanism, body location, severity, days of work lost, cost of the injury/incident) and prescribed opioids (buprenorphine, fentanyl, hydromorphine, methadone, morphine and oxycodone), including opioid type, morphine equivalent dose and prescription duration.

Statistical analyses will describe participant and prescribed S8 opioid characteristics; calculate the rate of opioids prescribed after a work-related injury and subsequent adverse events; and identify predictors of S8 prescribed opioids being dispensed and length of time off work. Time series analyses will enable more sensitive analysis simply comparing prevalence at different time points.

Why are we undertaking this research?

There has been an exponential increase in the dispensing of prescribed opioids in Australia, following similar trends in North America. There is evidence of associated adverse events including iatrogenic dependence and poisonings [1].

Workers may be particularly vulnerable to the adverse consequences of prescribed opioid use. In South Australia (SA) 47% of the population (approximately 803,000 individuals) are workers. The most common injuries for which workers seek compensation in SA (and those which incur the highest cost to the compensation system) are traumatic joint/ligament and muscle/tendon injuries, musculoskeletal and connective tissues diseases and fractures [2]. These injuries may be extremely painful, and require pain relief.

International studies have reported that workers prescribed opioids following a work-related injury are more likely to have a work-related disability 12 months after the injury [3], and have significantly higher prescriptions, costs, time off work, and morbidity compared to workers not prescribed opioids [4,5]. However, these studies often do not cover all workers in a jurisdiction and/or are limited to lower socio-economic status workers.

An imperative exists to provide appropriate pain relief while minimising unintended consequences and promoting return to work. This is hampered by evidence gaps regarding which workers are vulnerable to adverse outcomes after being prescribed opioids for a work-related injury.

What will it mean?

This study will improve our understanding of worker health, well-being, and return to work following a work-related injury. In particular, the extent, nature, and impact of prescribed opioid use on workers with work-related injuries.

Where to next?

This study is part of a larger research program examining the use of opioid, stimulant and benzodiazepine medications and adverse outcomes amongst South Australians. NCETA will commence an examination of the relationship between dispensed prescribed opioid and stimulant (prescribed and not-prescribed) use and road-related incidents, as well as medication use and associated adverse outcomes amongst older people (aged 60+ years).