Increasing Prevalence of Long-Term Antidepressant Use in Australia: A Retrospective Observational Study.

BACKGROUND: Long-term antidepressant use may reduce the risk-benefit profile due to the increased likelihood of withdrawal symptoms and higher incidence of side effects. This epidemiological study investigates historical trends in long-term antidepressant use, which was defined as maintaining continuous antidepressant use for at least 365 days, allowing for gaps in dispensing of up to 60 days in the Australian community from 2014 to 2023. METHOD: A retrospective analysis was conducted using a 10% sample of data from the Australian Pharmaceutical Benefits Scheme (PBS), including patients aged over 10 years who had been dispensed a PBS-listed antidepressant between January 2014 and December 2023. RESULTS: From 2014 to 2023, the prevalence of long-term antidepressant use increased from 66.1 to 84.6 per 1000 population. Age-stratified analysis showed that the 10-24 age group had the highest relative increase in long-term user prevalence (110%) and in the proportion of long-term users (35%). The average duration of the treatment episode increased by 25% across all ages, with the 10-24 group showing the largest rise (56%). The percentage of long-term users with apparent dose reductions showed minimal change over time. CONCLUSIONS: The study highlights a growing trend in long-term antidepressant use across all age groups, particularly among those aged 10-24, warranting further investigation into the underlying factors. The extended treatment duration, coupled with limited medicine apparent dose reduction efforts, may suggest overprescription and underuse of deprescribing strategies. A more comprehensive mental health approach is needed, integrating effective deprescribing practices and emerging technological interventions.