Post-traumatic Stress Disorder in Australia: Results from the 2020-2022 National Study of Mental Health and Wellbeing

BACKGROUND:Post-traumatic stress disorder is a leading driver of distress and premature mortality. OBJECTIVE:To provide contemporary, nationally representative estimates of post-traumatic stress disorder in Australia using data from the Australian population-based 2020-2022 National Study of Mental Health and Wellbeing, including sex-specific prevalence, remission and comparisons with the 2007 National Study of Mental Health and Wellbeing. METHODS:Post-traumatic stress disorder and 14 other Diagnostic and Statistical Manual of Mental Disorders (4th ed.) disorders were assessed with the World Mental Health Composite International Diagnostic Interview 3.0. Kaplan-Meier survival analysis estimated projected lifetime risk and time to remission. Cox regression tested for projected lifetime remission. Logistic regression tested associations between post-traumatic stress disorder and demographic, mental health, and physical health variables, and prevalence changes between the 2007 and 2020-2022 surveys. RESULTS:Lifetime post-traumatic stress disorder prevalence (n = 15,893) was 7.1%. Females had higher odds than males (odds ratio = 2.3, confidence interval = [2.0, 2.7]) of post-traumatic stress disorder diagnosis. Projected lifetime risk was 9.6% and higher for females (12.3%) than males (6.4%; hazard ratio = 2.2, standard error = 0.10). Projected lifetime remission was 63.3%, with higher remission for males than females (68.7% vs 61.2%; hazard ratio = 0.81; standard error = 0.10). Three quarters entered remission after 10 years for males and 20 years for females. Individuals with post-traumatic stress disorder had higher odds of experiencing any anxiety disorder (adjusted odds ratio = 6.0, confidence interval = [5.0, 7.3]), any mood disorder (adjusted odds ratio = 4.8, confidence interval = [3.9, 5.9]), sedative use disorder (adjusted odds ratio = 7.9, confidence interval = [3.9, 15.9]), suicidality (adjusted odds ratio = 5.0, confidence interval = [4.2, 5.9]), asthma (adjusted odds ratio = 2.0, confidence interval = [1.7, 2.4]) and diabetes (adjusted odds ratio = 1.8, confidence interval = [1.2, 2.6]). No differences in post-traumatic stress disorder diagnosis were observed between the 2007 and 2020-2022 surveys. CONCLUSION:Post-traumatic stress disorder remains a prevalent and chronic condition in Australia, frequently co-occurring with other mental and physical health conditions and characterised by significant sex differences in risk and remission.