The 2007 National Survey of Mental Health and Wellbeing found that nearly half (45.5%) of the Australian population aged 16-85 years had experienced an anxiety, affective or substance use disorder at some stage in their lifetime (table 2-1). This is equivalent to almost 7.3 million people.
In the 12 months prior to interview one in five (20.0%) of the population had mental disorders. This is equivalent to almost 3.2 million Australians experiencing mental disorders in the previous 12 months, and many of these will have experienced more than one mental disorder over the 12 month period.
Anxiety disorders were the most common class of mental disorder in the 12 months prior to interview. One in seven (14.4%) Australians had an anxiety disorder in the previous 12 months. One in 16 had an affective disorder (6.2%) and one in 20 had a substance use disorder (5.1%).
Based on these prevalence figures, nearly 1 million people experienced affective disorders, over 2.3 million anxiety disorders and over 800,000 substance use disorders in the previous 12 months.
Table 2-1: Prevalence of lifetime and 12-month mental disorders
| Disorder | Lifetime prevalence (%) | Lifetime prevalence Population estimate | 12-month prevalence (%) | 12-month prevalence Population estimate |
|---|---|---|---|---|
| Affective disorders | 15.0 | 2,405,000 | 6.2 | 996,000 |
| Anxiety disorders | 26.3 | 4,205,000 | 14.4 | 2,303,000 |
| Substance use disorders | 24.7 | 3,960,000 | 5.1 | 820,000 |
| Any mental disorder | 45.5 | 7,287,000 | 20.0 | 3,198,000 |
Note: Totals are lower than the sum of disorders as people may have had more than one class of mental disorder in the 12 months.