Depression is a highly prevalent condition, affecting about 150 million people worldwide at each moment in time.
Currently, depressive disorders are the third disorder worldwide in terms of disease burden, and will be the disorder with the highest disease burden in high-income countries in 2030. Furthermore, depressive disorders are associated with huge losses in quality of life in patients and their relatives, with increased mortality rates, with high levels of service use, and with enormous economic costs.
Shifting from curing to preventing
Much of the disease burden, and economic costs of depressive disorders is associated with the very high incidence of depression. About 48% of all patients with a depressive disorder in the past year, indicate that they had that depression for the first time in their lives, although some of them may have been cases of recurrent depression. The same is true for the economic costs of depressive illnesses. About 47% of the costs of prevalent cases is associated with incident cases. While mental health care is mainly aimed at treating depressed patients, hardly anything is done about the vast influx of new cases who develop a depression for the first time in their lives.
Prevention is also important because current treatments can reduce the disease burden of depression only to a limited extent. A recent modeling study in Australia estimated that about 16% of the disease burden of major depression is averted in the current health system. Because many patients do not receive an evidence-based treatment, this percentage could rise to 23% if all patients would receive such an evidence-based treatment. Furthermore, about 40% of all people with a depressive disorder do not receive any treatment. If it would be possible to deliver treatment to all patients with a depressive disorder, 34% of the disease burden of depression could be averted. So, although current treatments are usually considered to be effective in treating depressive disorders, it is estimated that these treatment can reduce the disease burden of depression by a maximum of 34% (Andrews et al., 2004).