June 4, 2008 -- Good news for a change.
About half of people who have a first episode of major depression are likely, upon recovery, to stay well — to stay depression-free, according to a new study.
This rate, based on a large study of 1,831 people, including 92 with depression, is reported in the May issue of the Archives of General Psychiatry by researchers William Eaton, Peter Zandi and colleagues at the Johns Hopkins School of Public Health.
The results should be encouraging to patients and their families, and to the doctors and therapists who treat them, because they suggest a better prognosis than do other studies of this kind.
This study, which followed people in Baltimore over a 23-year period, is unique in focusing on those in the community, rather than on those who have sought psychiatric attention. That means the results tell us a lot about depression in general, rather than simply telling us about the more severe cases of the illness.
To understand the value of such a study, consider an analogy. If we wanted to understand the full range of singing ability in the population, we would not want to only sample those who showed up for American Idol competitions, because these are (mostly) people with some talent. By contrast, if every United States citizen had to participate, we would see a wider range of abilities, including those with more modest talents.
Similarly, sampling the general population tells us more about milder depressions than does studying groups of patients found through clinics.
The Art of Prognosis
Prognosis is an ancient medical art. It refers to the physician's ability to see into the future and predict how an illness is likely to unfold. For millennia, this was the physician's skill par excellence as practitioners had relatively little in their bag of tricks with which to actually cure patients of disease.
Sometimes prognosis can be as good as a cure. For example, if a patient has huge lymph nodes and is afraid that he has a form of cancer, but the physician determines that it is only a viral infection which will likely clear up within a couple of weeks, then the patient is much relieved, knowing that a return to good health is imminent.
Patients who experience a first episode of depression may be not only plunged into the misery of the episode itself, with the many losses it entails — of energy, concentration, motivation, self-confidence, even the will to live — but also bedeviled by the prospect that they might never fully be themselves again.
A patient of mine was an active woman, a mother of two young children, who worked part-time for a local non-profit organization. She had been entirely psychologically healthy when she was struck by a major depressive episode that robbed her of her usual energy and good cheer, her confidence, and her sense of stability.
Even as she responded quickly to antidepressant medication, the question she kept asking was "Is this going to happen again?"
A Brighter Future
Some previous studies have suggested that the likelihood of the return of depression is much higher.
For example, a study from the NIMH Collaborative Program on the Psychobiology of Depression reported that 85 percent of people with depression followed over a period of 15 years experienced a second episode of illness.
But these were all people who came to psychiatric attention at academic medical centers; they might have been sicker than most.
The newly reported study is consistent with some others, such as one from Sweden that followed 344 people from the community with a first episode of either major depression or a milder form of the illness, and found that, over many years, 60 percent remained free of illness once they recovered.
Several other prior studies found rates of depression recurrence in the 40 to 60 percent range.
So, in depression, there are grounds for seeing the glass as half full. Half of people recover and never experience the illness again.
Let us all strive to keep our eye on what is in the glass rather than what is not.
Obviously this is not easy to do for someone who is depressed. I am reminded of a psychiatrist whom we treated for depression on our inpatient Mood Disorders Service at Johns Hopkins. While gloomy about his condition and his prognosis, he was struck by the upbeat approach that our doctors and staff took towards him, calling us "militantly optimistic."
My response: "guilty as charged, but we don't see much use in being anything else."
Dr. James Potash is an Associate Professor of Psychiatry and Co-Director of the Mood Disorders Program at the Johns Hopkins School of Medicine in Baltimore, Maryland. If you have questions or comments, please email at firstname.lastname@example.org. To participate in our genetic and clinical studies, call 1-877-MOODS-JH.