Prognosis

The risk of recurrent or chronic depression following an index episode is high.

Most patients make some recovery:

• 50-60% make at least a brief recovery within a year
• 90% make a recovery within 5 years

If a weighted average of mood is taken over the longer term then it is apparent that recurrence is common:

• 43% are improved at one year
• only 24% are improved at 5 years
• 25% will become depressed again within one year of an index episode
• 75% will eventually have recurrent depression

Chronic depression is common:

• 25% of depressed patients will become chronically depressed

Reference:

• Angst, J. (1997). A regular review of the long term follow up of depression. BMJ, 315, 1143-4.