Prevalence of mental disorders among older Australians: Contrasting evidence from the 2020–2021 National Study of Mental Health and Wellbeing among men and women and the Health In Men Data Linkage Study

Objective: To determine the prevalence of common mental disorders among older Australians included in the Health In Men Data Linkage Study and compare those with the results of the 2020–2021 National Study of Mental Health and Wellbeing (NSMHW). Method: We used longitudinal record linkage to estimate the prevalence of mental disorders from age 65 years in a random sample of 38173 Australian men aged 65–85 years living in the Perth metropolitan region. Outcome was the proportion of participants affected by depressive episodes or dysthymia, bipolar disorder, anxiety disorder, psychotic disorder and alcohol use disorder. Results: Prevalence estimates for participants aged 65–69, 70–74, 75–79, 80–84 and ≥85 years were 0.9%, 2.0%, 3.6%, 5.8% and 12.6% for depressive, 0.2%, 0.3%, 0.4%, 0.4% and 0.7% for bipolar, 0.1%, 0.5%, 1.3%, 2.2%, 6.9% for anxiety, 0.2%, 0.4%, 0.5%, 0.4% and 0.6% for psychotic and 1.2%, 1.7%, 2.1%, 2.2% and 4.2% for alcohol use disorders. Conclusions: In contrast to the NSMHW, our data indicate that the prevalence of depressive and anxiety disorders increases with age, particularly among the older old. We conclude that the NSMHW should not be relied upon to guide planning or policies to address the mental health needs of older Australians.