COVID-19 restrictions and the incidence and prevalence of prescription opioid use in Australia - a nationwide study.

The COVID-19 pandemic has disrupted seeking and delivery of healthcare. Different Australian jurisdictions implemented different COVID-19 restrictions. We used Australian national pharmacy dispensing data to conduct interrupted time series analyses to examine the incidence and prevalence of opioid dispensing in different jurisdictions. Following nationwide COVID-19 restrictions, the incidence dropped by -0.40 (95% confidence interval [CI]: -0.50, -0.31), -0.33 (95% CI: -0.46, -0.21) and -0.21 (95% CI: -0.37, -0.04) per 1000 people per week and the prevalence dropped by -0.85 (95% CI: -1.39, -0.31), -0.54 (95% CI: -1.01, -0.07) and -0.62 (95% CI: -0.99, -0.25) per 1000 people per week in Victoria, New South Wales and other jurisdictions, respectively. Incidence and prevalence increased by 0.29 (95% CI: 0.13, 0.44) and 0.72 (95% CI: 0.11, 1.33) per 1000 people per week, respectively in Victoria post-lockdown; no significant changes were observed in other jurisdictions. No significant changes were observed in the initiation of long-term opioid use in any jurisdictions. More stringent restrictions coincided with more pronounced reductions in overall opioid initiation, but initiation of long-term opioid use did not change.