The worst outcome from unipolar major depression is death. According to the Johns Hopkins Hospital website, an unbelievable 15 percent of people with severe depression kill themselves. Think about it this way. If you were in an emergency room sitting next to six other severely depressed individuals, one of you would end up taking your own life. You do not want this to happen to you or anyone you care about.
Most unipolar major depression is undiagnosed, and most suicides are unreported, so the true number of suicides is probably a lot higher. Many more deaths from supposed automobile and pedestrian accidents, drowning, fatal falls, and so forth, are really suicides without warning, explanation, or suicide notes.