Anticipating the effects of restricting high-dose preparations of strong opioids in Australia: A population-based analysis to inform the current policy debate.

Abstract

Countries worldwide are developing a variety of strategies to combat the opioid epidemic, such as restricting access to high-strength opioid formulations. We aimed to examine the dispensing patterns of strong opioids by dose units (DUs), age, and sex. We used Australian population-level dispensing data from January 2003 to December 2015 and categorised strong opioids by DU: very low, low, moderate, and high, corresponding to total daily doses of less than or equal to 25, 26 to 50, 51 to 100, and greater than 100 morphine milligramme equivalents, respectively. We measured trends in strong opioid use as dispensings/1000 population/year and stratified dispensing in 2015 by patient age and sex. From 2003 to 2015, strong opioid dispensing of very low, low, moderate, and high DU increased 6.7-, 6.2-, 2.2-, and 1.8-fold, respectively. The increase in very low and low DU dispensing was driven primarily by oxycodone (5, 10, and 15mg tablets and capsules) and buprenorphine transdermal patches. In 2015, the number of dispensings/1000 population for very low, low, moderate, and high DU were 180.3, 77.0, 52.7, and 34.8, respectively. Females aged greater than or equal to 85years had the highest opioid use, ranging from 157.1 dispensings/1000 population for high DU to 2104.5 dispensings/1000 population for very low DU. In contrast, the high DU dispensings in males aged 25 to 64years exceeded their female counterparts by approximately 1.3-fold. Relative to moderate and high DU strong opioids, dispensing of very low and low DU strong opioids increased dramatically during the study period in Australia. Future studies investigating opioids use and harms in elderly females and males between 25 to 64years are warranted.