Trends in opioid utilisation in Australia, 2006‐2015: Insights from multiple metrics

摘要

Abstract Purpose Population‐based observational studies have documented global increases in opioid analgesic use. Many studies have used a single population‐adjusted metric (number of dispensings, defined daily doses [DDDs], or oral morphine equivalents [OMEs]). We combine these volume‐based metrics with a measure of the number of persons dispensed opioids to gain insights into Australian trends in prescribed opioid use. Methods We obtained records of prescribed opioid dispensings (2006‐2015) subsidised under Australia's Pharmaceutical Benefits Scheme. We used dispensing claims to quantify annual changes in use according to 3 volume‐based metrics: DDD/1000 pop/day, OME/1000 pop/day, and dispensings/1000 pop. We estimated the number of persons dispensed at least one opioid in a given year (persons)/1000 pop using data from a 10% random sample of Pharmaceutical Benefits Scheme‐eligible Australians. Results Total opioid use increased according to all metrics, especially OME/1000 pop/day (51% increase) and dispensings/1000 pop (44%). Weaker opioid use remained stable or declined; strong opioid use increased. The rate of persons accessing weaker opioids only decreased 31%, and there was a 238% increase in persons dispensed only strong opioids. Strong opioid use also increased according to dispensings/1000 pop (140%), OME/1000 pop/day (80%), and DDD/1000 pop/day (71% increase). Conclusions Our results suggest that the increases in total opioid use between 2006 and 2015 were predominantly driven by a growing number of people treated with strong opioids at lower medicine strengths/doses. This method can be used with or without person‐level data to provide insights into factors driving changes in medicine use over time.