Antidepressant prescribing patterns in Australia

BACKGROUND: The Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for mood disorders (MDcpg(2015) and MDcpg(2020)) provide evidence-based and consensus-based recommendations for managing mood disorders. AIMS: We examined Australian real-world prescribing habits to determine whether management in clinical practice aligned with MDcpg(2015) recommendations. METHOD: A retrospective analysis of a cohort of patients ≥16 years old who had been dispensed a Pharmaceutical Benefits Scheme (PBS)-listed antidepressant between July 2013 and June 2019 was conducted using Australian Commonwealth Department of Human Services PBS 10% sample data. RESULTS: Between July 2013 and June 2019, 239 944 patients in Australia commenced antidepressant treatment. Of these, 22% (52 694 patients) received a second treatment (a new class of treatment after a period of discontinuation or additional antipsychotic therapy) and 6% (15 741 patients) received a third treatment. Patients were initially prescribed primarily selective serotonin reuptake inhibitors (SSRIs; 52% of prescriptions) or tricyclic antidepressants (TCAs; 25%), even though TCAs are not recommended for first-line treatment. Fewer than one-quarter of patients were prescribed serotonin–noradrenaline reuptake inhibitors (13%) or other agents (10%). General practitioners (GPs) were more likely to initiate TCAs than psychiatrists (22% v. 7%). Once initiated, the overall median time patients remained on treatment was 4.5 months; this was highest with SSRIs (5.8 months) and lowest with TCAs (0.9 months). CONCLUSIONS: First-line prescribing broadly follows guidelines. GP and psychiatrist prescribing patterns differ, perhaps reflecting different patient groups and the need to tailor treatment to individuals. Future guidelines should aim to capture the different presentations and complexity of depression.