A nationwide analysis of prescription data reveals that young Australians are staying on antidepressants for longer than ever, highlighting growing gaps between clinical guidelines and real-world practice.
Increasing Prevalence of Long-Term Antidepressant Use in Australia: A Retrospective Observational Study. Image Credit: marevgenna / Shutterstock
A recent study published in the journal Pharmacoepidemiology and Drug Safety highlights a steadily increasing prevalence of long-term antidepressant use in Australia, especially among adolescents and young adults aged 10 to 24 years.
Expanding Antidepressant Use and Safety Concerns
Antidepressants are widely prescribed medications for the treatment of various mental health conditions, including depression, anxiety, and panic disorder. However, clinical evidence indicates that a significant proportion of antidepressant prescriptions do not align with the officially approved therapeutic uses.
Clinical guidelines recommend a 6–12 month duration of antidepressant therapy for the optimal management of depression. For high-risk patients, therapy duration can be extended to reduce the risk of relapse.
However, a growing trend in antidepressant therapy for more than one year or longer has been observed in many countries, including the United Kingdom, Italy, and Sweden. In Australia, a continuous long-term use of antidepressants has been observed among users even in the absence of clearly documented clinical indications.
This trend of long-term antidepressant use has raised significant clinical concerns regarding the possibility of potential adverse effects, as well as the risk of withdrawal symptoms of varying intensity and duration that may arise after treatment cessation.
Rationale for Studying Long-Term Treatment Trends
Given the potential negative consequences associated with long-term antidepressant use and the limited evidence describing national long-term utilisation patterns, University of South Australia researchers conducted an epidemiological study to understand the trends in long-term antidepressant use in Australia between 2014 and 2023.
The researchers analyzed a 10% population-based sample of patients from the Australian Pharmaceutical Benefits Scheme (PBS), which included a complete record of PBS-subsidised antidepressant dispensings for individuals aged 10 years and above, excluding most inpatient hospital medicines and private prescriptions.
Rising Antidepressant Use Across the Population
The study analysis revealed that the prevalence of antidepressant use had increased from 107.7 per 1000 population in 2014 to 128.8 per 1000 population in 2023, with a notable acceleration during the coronavirus disease 2019 (COVID-19) pandemic period.
The annual proportion of new users rose from 29.4 per 1000 population in 2014 to a peak of 32.4 per 1000 population in 2021, before declining back to 29.4 per 1000 population in 2023. The proportion of new users relative to prevalent users gradually declined over time, with the lowest percentage observed in 2023.
Growth in Long-Term Antidepressant Treatment
Regarding long-term antidepressant use, the study found an overall increase from 66.1 per 1000 population in 2014 to approximately 85 per 1000 population by 2022, with a small decline to 84.6 per 1000 population in 2023. The analysis by gender revealed a consistently higher prevalence among female users during the entire study period.
The increased prevalence of long-term antidepressant use was observed across all age groups, with the highest increase observed in the 10–24 years age group (110%), corresponding to a rise from 15.4 to 32.3 per 1000 population, and the second largest increase observed in the 25–39 years age group (37%).
Lengthening Duration of Antidepressant Therapy
Regarding the duration of antidepressant therapy, the study found a 25% increase across all age groups during the study period. The analysis by age revealed that the therapy duration was longer in older age groups compared to that in younger age groups. However, the highest increase in duration was observed in the 10–24 years age group, which was a 56% increase between 2014 and 2023. Average treatment duration was estimated using prevalence–incidence relationships rather than direct observation of individual treatment episodes. Long-term use was defined as continuous antidepressant treatment for at least 365 days, allowing short gaps between dispensings.
The percentage of long-term users with apparent dose reductions showed minimal change over time. These dose reductions were identified using dispensing-based metrics and may not always reflect intentional clinical deprescribing.
Clinical Implications for Prescribing and Deprescribing
The study highlights an increasing trend in long-term antidepressant use across all age groups in Australia, particularly among patients aged 10–24 years. A similar increasing trend in treatment duration has been observed, which is accompanied by limited efforts in apparent dose reduction.
According to the Royal Australian and New Zealand College of Psychiatrists (RANZCP) Clinical Practice Guidelines published in 2015, 2017, and 2021, antidepressant therapy should be continued for 6–12 months after symptom remission. The guidelines also recommend extending treatment duration for patients with recurrent depressive disorder.
Despite these guidelines, this study finds a significant increase in long-term antidepressant use and treatment duration and a reluctance to deprescribe. These observations raise vital concerns about potential over-prescription, difficulty in withdrawing from therapy, and suboptimal deprescribing practices.
Factors Driving Antidepressant Use Among Younger Adults
The most concerning trends in antidepressant use have been observed in the 10–24-year age group, which showed a 110% increase in long-term antidepressant use and a 56% increase in treatment duration between 2014 and 2023. An exponential rise in social media use in the last decade and its negative influence on mental health may have contributed to the observed trend. Furthermore, social isolation and movement restrictions imposed during the COVID-19 pandemic may also have adversely affected mental health in young people.
The expansion of healthcare services, particularly telemedicine, has improved access to mental health care among young people. Although encouraging the youth to seek medical help more proactively, these services may also contribute to unnecessary initiation of pharmacological interventions, suboptimal deprescribing practices, and the overprescription of antidepressants.
Need for Improved Mental Health Strategies
These adversities in clinical practice should be addressed by promoting current guidelines that recommend psychological strategies, such as cognitive behavioral therapy, as first-line and primary treatments for young people with mental health conditions, with pharmacological therapy reserved for selected cases or used as adjunctive treatment.
Considering the overall findings, researchers highlight the need for comprehensive research to investigate the complex relationships among non-pharmacological management practices, healthcare provider attitudes, and patient acceptance.