Major depressive disorder diagnoses can fall roughly into two camps: people who have just a handful of depressive episodes, and people who have persistent, episodic bouts of depression. The majority of the roughly 300 million global depression cases fall into the latter category. As University of Pittsburgh psychiatry professor David J. Kupfer explains, “While the diagnosis can be based on a single episode, in general the disorder is a recurrent one associated with interepisode remissions in the majority of cases.” (To give a sense, the median depressive episode is at least three months.)
Most scientific studies of depression have focused on the majority group — people who experience recurring episodes of depression. But there is a sizable subset of people whose depression does not recur after their first depressive episode. In a paper forthcoming from the peer-reviewed journal Perspectives on Psychological Science, researchers think learning why people with few depressive episodes recover may even help to aid those with persistent depression. “We argue that there is an overlooked group who, despite a history of depression, will go on to thrive, functioning above the level of the average nonpsychiatric person,” the authors write.
The authors cite research showing that somewhere in the range of 40 to 50 percent of people with depression achieve “optimal well-being” — meaning, as lead author Jonathan Rottenberg told The Outline, “your depression must be gone for at least a year.”
A 2016 study of 2,528 Canadians with major depression diagnoses found that 39 percent have gone at least a full year without a depressive episode. A similar 2008 study of 3,481 people in East Baltimore concluded that “about 50% of first episode participants recovered and had no future episodes.”
Why some people improve after just a handful of depressive episodes is unclear. Rottenberg offers possible explanations ranging from treatment to — in select cases — the “passage of time.” But Rottenberg believes that understanding these cases of rapid improvement is essential to figuring out how the condition functions. People who have recovered “may be instructive if we consider them as people who carry within them a kind of ‘antidote’ to depression.” Rottenberg added to The Outline, “We need data from very large samples in order to answer this question.”
What’s clear to him is that researchers have overlooked the minority of people who have recovered from depression. That absence isn’t only a problem in depression research, either. As Rottenberg and his colleagues explain in their paper, “For most mental health conditions, we simply do not know how common it is for people to flourish afterwards for a prolonged period.”