Changes in antidepressant use in Australia: A nationwide analysis prior to and during the COVID-19 pandemic (2015-2021)

BackgroundDepression and anxiety affect 4% to 14% of Australians every year; symptoms may have been exacerbated during the COVID-19 pandemic. We examined recent patterns of antidepressant use in Australia in the period 2015 to 2021, which includes the first year of the pandemic. MethodsWe used national dispensing claims for people aged [≥]10 years to investigate annual trends in prevalent and new antidepressant use (no antidepressants dispensed in the year prior). We conducted stratified analyses by sex, age group and antidepressant class. We report outcomes from 2015 to 2019 and used time series analysis to quantify changes during the first year of the COVID-19 pandemic (March 2020 to February 2021). ResultsIn 2019 the annual prevalence of antidepressant use was 170.4 per 1,000 women and 101.8 per 1,000 men, an increase of 7.0% and 9.2% from 2015, respectively. New antidepressant use also increased for both sexes (3.0% for women and 4.9% for men) and across most age groups, particularly among adolescents (aged 10-17 years; 46%-57%). During the first year of the COVID-19 pandemic, we observed higher than expected prevalent use (+2.2%, 95%CI 0.3%, 4.2%) among females, corresponding to a predicted excess of 45,217 (95%CI 5,819, 84,614) females dispensed antidepressants. The largest increases during the first year of the pandemic occurred among female adolescents for both prevalent (+11.7%, 95%CI 4.1%, 20.5%) and new antidepressant use (+15.6%, 95%CI 8.5%, 23.7%). ConclusionAntidepressant use continues to increase in Australia overall and especially among young people. We found a differential impact of the COVID-19 pandemic in treated depression and anxiety, greater among females than males, and greater among young females than other age groups, suggesting an increased mental health burden in populations already on a trajectory of increased use of antidepressants prior to the pandemic. Reasons for these differences require further investigation.

Changes in dispensing of medicines proposed for re-purposing in the first year of the COVID-19 pandemic in Australia

ObjectiveWe quantified changes in dispensing of common medicines proposed for "re-purposing" due to their perceived benefits as therapeutic or preventive for COVID-19 in Australia, a country with relatively low COVID-19 incidence in the first year of the pandemic. MethodsWe performed an interrupted time series analysis and cross-sectional study using nationwide dispensing claims data (January 2017-November 2020). We focused on six subsidised medicines proposed for re-purposing: hydroxychloroquine, azithromycin, ivermectin, colchicine, corticosteroids, and calcitriol (Vitamin D analogue). We quantified changes in monthly dispensing and initiation trends during COVID-19 (March-November 2020) using autoregressive integrated moving average models (ARIMA) and compared characteristics of initiators in 2020 and 2019. ResultsIn March 2020, we observed a 99% (95%CI 96%-103%) increase in hydroxychloroquine dispensing (of which approximately 22% attributable to new use), and a 199% increase (95%CI 184%-213%) in initiation, with a shift towards prescribing by general practitioners (42% in 2020 vs 25% in 2019) rather than specialists. These increases subsided following regulatory restrictions on prescribing to relevant specialties. There was a small but sustained increase in ivermectin dispensing over multiple months, with a 80% (95%CI 42%-118%) increase in initiation in May 2020 following its first identification as potentially disease-modifying in April. Other than increases in March related to stockpiling, we observed no increases in initiation of calcitriol or colchicine during COVID-19. Dispensing of corticosteroids and azithromycin remained lower than expected in April through November 2020. ConclusionsWhile most increases in dispensing observed early on during COVID-19 were temporary and appear to be related to stockpiling among existing users, we did observed increases in initiation of hydroxychloroquine and ivermectin and a shift in prescribing patterns which may be related to media hype around these medicines. A quick response by regulators can help limit inappropriate repurposing to lessen the impact on medicine supply and patient harms.