Epidemiology of anxiety disorders

This contribution provides an overview of the most important recent epidemiological studies examining anxiety disorders in the general population. Results demonstrate that anxiety disorders are widespread, with lifetime prevalence rates ranging between 13.6% and 28.8% in Western countries. Comorbidity among individuals with an anxiety disorder is high: three out of four people with a lifetime anxiety disorder experience at least one other mental disorder in their lifetime. There is a particularly strong association between anxiety disorders and affective disorders and a considerably lower but still substantial relation between anxiety disorders and substance use disorders. Shared risk factors and causal relationships between disorders are discussed as possible sources of comorbidity. Individuals between the ages of 10 and 25 seem to be at the highest risk for developing an anxiety disorder. Other risk factors comprise female gender, behavioural inhibition and negative life events. Most anxiety disorders are associated with unemployment, low education, low income, and not being married. This contribution further presents a summary of the first results from a worldwide epidemiological assessment of mental disorders. The WHO has recently initiated nationwide mental health surveys with shared methodological standards in 28 countries around the world. Findings will increase our knowledge of the mental health status in less developed areas and allow for intercultural comparison of prevalence rates. To date, 14 surveys have been completed. Twelve-month prevalence rates for six anxiety disorders are presented and potential causes for variations in prevalence rates are discussed.