Interplay between psychological distress, income inequality, mental health-related medication use and consultations with a psychologist: Australian population-level data between 2011 and 2018.

Aims: The aim of the study was to examine the interplay between income inequality, psychological distress, medication use and access to psychologist consultations in Australia.

Methods: Hypothesis-driven secondary data analysis was conducted using nationally representative data from the 2011-2012, 2014-2015 and 2017-2018 Australian National Health Surveys. Approximately 12,000 working-age participants (18-64 years) were analysed per survey year, with subgroup interaction effects (p < 0.1) explored.

Results: Overall, 16% of participants reported taking medications, and 5% consulted a psychologist in the past year. About 14% experienced high distress, and 5% had very-high distress in the past month. Lower-income individuals were more likely to experience high psychological distress and use mental health medications. Specifically, 30% of adults in the lowest income quintile used medications, and 14% reported very-high distress, compared to 10% and 2% in the highest income group. More low-income individuals (9%) consulted a psychologist compared to high-income individuals (4%). Interaction analyses revealed that lower-income individuals who used medication or saw a psychologist exhibited up to four times higher distress than those in higher-income groups.

Conclusions: The findings reveal a concerning disparity when combined with other national data: individuals in the lowest income quintile face higher mental health symptoms, greater medication use, and are more likely to consult a psychologist, yet receive fewer consultations. This exploratory work deepens understanding of the complex relationship between income inequality, mental health symptoms, medications and healthcare utilisation in well-resourced countries like Australia. With mental ill-health rising globally, understanding these dynamics is crucial for designing equitable mental health policies.