Tuesday, February 3, 2009
Four and a half years ago, I sat down with leading bipolar expert Ellen Frank PhD of the University of Pittsburgh. I asked her to talk about a study she had been involved in concerning mixed depressions, that is, depression with some features of mania.
"What we've been arguing about is that even isolated symptoms that don't cluster together to create episodes may be important," she told me.
Emil Kraepelin, the pioneering diagnostician who coined the term manic-depression, recognized back in the early twentieth century that depression and mania could combine together to produce no fewer than six mixed states. Yet the DSM recognizes only one - full-blown mania with full-blown depression. By this criteria, only those with bipolar I are recognized as having mixed states.
The DSM is due for revision in 2012, and clearly things need to change. This month's American Journal of Psychiatry features the latest findings to emerge from the NIMH-underwritten STEP-BD real world clinical trials on bipolar patients.
In the study, of 1,380 patients diagnosed with bipolar depression, 54 percent had co-occurring subthreshold (one to three) manic symptoms while another 15 percent had a full mixed episode (at least four manic symptoms). Significantly, 71 percent of the mixed population had a bipolar II diagnosis. Only one-third of the patients had "pure" bipolar depression - that is, depression with no mania symptoms.
More than two thirds of the mixed population showed marked or severe irritability (think road rage). The mixed group were also more prone to attempt suicide. Common manic symptoms included distractibility, racing thoughts, and psychomotor agitation. We are talking depression with unwanted add-ons, and, not surprisingly, these depressions are more difficult to treat.
An earlier series of STEP-BD studies found that adding an antidepressant to a mood stabilizer did not, as expected, induce more switches into mania in the "pure" depression group. But this changed for the "mixed" group. As the study authors pointed out, clinicians who fail to pick up mania symptoms in depression may mistakenly "assume a beneficial role for antidepressant psychopharmacology."
Leading researchers such as Hagop Akiskal MD of the University of California, San Diego have advanced strong cases that the "mixed" population is much larger than psychiatry recognizes. STEP-BD now provides overwhelming evidence in support of this proposition.
Mixed states also jump the artificial divide between bipolar and unipolar depression. Perhaps even more important than knowing whether you have unipolar depression or bipolar is knowing precisely how "mixed" your depressions (and manias and hypomanias) are.
Chances are your psychiatrist is operating on the assumption that your depression is just depression. Maybe, maybe not. The onus is on you to get a dialogue going. Now more than ever, "knowledge is necessity."
Further reading from mcmanweb:
Treating Bipolar Depression
When Nassir Ghaemi MD of Tufts University was in residency at McLean Hospital, he assumed there was no harm in using antidepressants to treat bipolar depression. After all, "depression was depression," or so he and just about every clinician thought.
The Mood Spectrum
So what do we do with these irritable and depressed people with or without mixed states that the DSM presently ignores?