Mixed features are common in practice but poorly described in DSM. They are caused by the overlap of depressive and manic symptoms, but it’s hard to understand them by reading separate descriptions of these two states. It would be like trying to imagine green by studying yellow and blue.
Classic hypomania is difficult enough to detect. These euphoric states are brief, rare, and easily forgotten. Mixed cases bring a different set of challenges. Mixed features cause intense desperation. Rather than missing their appointments in a carefree, hypomanic bliss, these patients often call for urgent appointments. The issue is not that these states will be forgotten, but that they’ll present with symptoms that resemble those of many other psychiatric disorders.
A diagnostic chameleon
Mixed features can look like anxiety, ADHD, borderline personality disorder, or depression with an agitated edge. The Table contrasts the features of hypomania as they appear in mixed and pure forms. Unlike euphoric hypomania, mixed symptoms are not pleasurable, and the interview needs to be adjusted to capture that.
Ask a patient with mixed features, “Do you have times when you don’t need much sleep” and he or she will answer “No.” In truth, these patients do keep going with little rest, but they usually have a strong desire to sleep. Often the desire is not to sleep but to “turn my mind off,” a dangerous wish that can lead to sedative overdose when sleep does not come.
Ask a patient with mixed features, “Do you feel unusually confident, happy, or euphoric” and you’ll get a big “No.” How does confidence look when mixed with depression? Self-esteem is low, but patients are also demanding and aggressive, asserting themselves in a way that’s not consistent with the usual passivity of depression. Euphoria is replaced by lability, and most of these patients recall only the aversive turns of that emotional carousel. Relatives, on the other hand, may notice rare bursts of giddy excitation.1
Dr. Aiken is the Director of the Mood Treatment Center, Editor in Chief of The Carlat Psychiatry Report, and Instructor in Clinical Psychiatry at the Wake Forest University School of Medicine. He does not accept honoraria from pharmaceutical companies but he receives honoraria from W.W. Norton & Co. for Bipolar, Not So Much, a book he coauthored with Jim Phelps, MD.
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