Age of onset of major depression seems to be dropping in Western nations. Generally, early onset of a disorder is predictive of a more serious illness with a relatively poor prognosis. Since depression is associated with suicide, this begs the question of whether early onset of depression is associated with the degree of intent of suicidal behaviour.

Data approximating suicidal process levels (see figure) were drawn from the relevant responses of 9,282 respondents to a nationally representative community survey conducted in 2001 through 2003 in the USA. The primary outcome measure was the retrospectively determined age of first major depressive episode. 

The figure shows that younger age of onset for depression was associated with higher levels of suicidal intent, irrespective of age at the time of interview. The influence of onset age on suicidal intent was greater for women than for men. 

If, as it seems to be, that early onset depression produces further movement along the suicidal process, and if the onset of depression is appearing at even younger ages, then the situation is doubly troubling since it predicts increases in depression and suicidal behaviour. The more pronounced trend for women may reflect their higher depression rates Worldwide.