Prevalence of mental disorders in older people
Epidemiological research suggests that around half of all lifetime mental disorders start by the
mid-teens, and three-quarters by the mid-20s, with later onset disorders being mostly secondary to
an existing mental disorder (Kessler et al. 2007). However, for some older people, their experience of
mental illness is a lifetime of living with a chronic or episodic disorder (Rickwood 2005).
At a general population level, the prevalence of mental illness decreases considerably with
increasing age, but there is only a small decrease in the proportion of older age groups who
experience high or very high levels of psychological distress (ABS 2012).
From the 2007 National Survey of Mental Health and Wellbeing of adults (ages 16–85 years)
we know that the prevalence of mental disorders is highest in the 25–34 age group (24%) and
decreases with increasing age to 6% of the 75–85 age group (Figure 6.4.1)(ABS 2008). For all age
groups, the prevalence of mental disorders is higher in females compared with males.