Study identifies predisposition to opioid dependence

As the fatal consequences of prescription overdoses have climbed in Australia, a recently published  study from Monash University identified key factors that could indicate a predisposition to persistent opioid use in patients without cancer.  

The population-based study examined a random sample of adults who were dispensed prescription opioid medications between 2013 and 2015 through the Pharmaceutical Benefits Scheme. It found that 2.6%t (more than 11,000 people) of patients without cancer became persistent users of opioids within 12 months of them being prescribed.¹

The Australian Institute of Health and Welfare (AIHW) recently reported that fatalities involving opioids have doubled over 10 years to 2016, overtaking road deaths and illicit drug overdoses as leading causes of death.²

‘Despite uncertainty about the benefits of long-term opioid analgesic use in the treatment of chronic non-cancer pain (CNCP), there is clear evidence of significant harms,’ the Monash researchers said. ‘In order to reduce harm from long-term opioid analgesic use, it is firstly necessary to understand who is at greatest risk of long-term or persistent use.’   

Researchers found a patient’s initial exposure to opioids prescribed by a healthcare provider influenced the likelihood of persistent use later on.

‘Opioid initiation with a transdermal formulation and higher total oral morphine equivalents (OME’s) strongly predicted persistent use,’ they said.

They also identified that external factors  such as older age, prior history of mental health comorbidities and use of non-opioid analgesics were indicators of future persistent opioid use.

Mental health disorders were identified as a particular concern by researchers. They cited previous studies that found a history of mental illness was common among those who died from prescription opioid overdose.

‘Prescribers need to establish a comprehensive multimodal management plan for people with mental health comorbidities and if a trial with opioids is necessary, consider ongoing review of opioid effectiveness, dose and duration,’ they said. This information may assist prescribers target monitoring and early interventions to reduce harm with long-term use of opioids.

‘For the treatment of chronic pain, we need to change prescribing culture and raise the level of awareness of other treatment options among patients. The goal of care, treatment expectations and intended duration should be agreed upon by patients and prescribers prior to opioid initiation,’ said Samanta Lalic, a pharmacist who was part of the research team.  

‘In many cases the safest and most effective way to treat chronic pain will involve a combination of therapies, including exercise, physiotherapy and non-opioid painkillers.’

References:

1. Gisev N, Bell JS, Korhonen MJ, Ilomäki J. Predictors of persistent prescription opioid analgesic use among people without cancer in Australia. BJCP 2018; 84 (6): 1267-1278. At https://bpspubs.onlinelibrary.wiley.com/doi/full/10.1111/bcp.13556 
2. Kerrigan J, Brooks R, Gorrell L. Opioid harm in Australia and comparisons between Australia and Canada. Australian Institute of Health. AIHW 2018 and Welfare 2018. At: https://www.aihw.gov.au/getmedia/605a6cf8-6e53-488e-ac6e-925e9086df33/aihw-hse-210.pdf.aspx?inline=true