Patterns of opioid use in New Zealand older adults, 2007-2018

Opioid use has increased globally, dramatically increasing opioid overdose, dependence, abuse and mortality. Limited research is available on opioid use patterns in older adults in New Zealand and internationally. This study aims to address this gap by determining the incidence and prevalence of opioid use among older adults (age ≥65 years) in New Zealand from 2007 to 2018.

This was a population-based retrospective cohort study conducted using New Zealand national administrative healthcare databases. The annual opioid use incidence (2008-2018) and prevalence (2007-2018) in older adults were determined and stratified by sex, age, and opioid type and strength. We used descriptive statistics to summarise the patterns of opioid dispensing. Data analysis was conducted using MS Excel, and data linking was performed using SQL software.

A total of 820,349 older adults were initiated on opioids during the study period. The overall incidence of opioid use in older adults showed a steady increase from 2008 to 2015; similarly, the prevalence steadily increased from 2007 to 2015, and thereafter, both rates fluctuated. A slight decrease in both prevalence and incidence rates was observed in 2018. Codeine and tramadol were the most commonly dispensed opioids during the study period. Females had a higher incidence and prevalence of all opioids than males.

The incidence and prevalence of opioid dispensing increased in New Zealand older adults over time. Monitoring the trends of opioid use in older adults is critical to enable clinicians and policymakers to deliver early interventions to prevent future opioid-related adverse events.