From the Fall 2010 issue of bp Magazine.
It is the manic phase of bipolar disorder that attracts—no, demands—attention. But those who have the illness, or love someone who does, know it is depression that most disrupts and devastates lives—and dominates the course of the illness.
“Few people understand [that] depression sucks the life out of you,” says C.A., 52, of Oregon. “Desires, self-esteem, motivation, self-worth—any of those qualities that keep you going in life—disappear.” Since her 2002 bipolar diagnosis, she has gone only 18 consecutive months without depression.
When P.S. of Halifax, Nova Scotia, is sad, she sometimes avoids bike riding with her seven-year-old daughter. The guilt she feels at withdrawing from her child only intensifies her depression.
“You look at the functional outcomes, such as the ability to work, family life, being an active participant in society—this is largely driven by depressive, rather than manic, symptoms,” notes Roger S. McIntyre, MD, associate professor of psychiatry and pharmacology at the University of Toronto, and head of the Mood Disorders Psychopharmacology Unit at the University Health Network in Toronto.
One reason depression is more debilitating than mania is that it lasts longer; another is that it occurs more frequently: According to a 2002 study by Lewis L. Judd and colleagues at the University of California at San Diego published in the Archives of General Psychiatry, people with bipolar I experience depression three times as often as mania. For bipolar II, the ratio of time spent in depression versus mania is a whopping 40:1.
Bipolar depression is also difficult to diagnose, and therefore to treat. Some studies suggest that as many as 50 percent of those with bipolar disorder are misdiagnosed with unipolar depression, according to Michael E. Thase, MD, professor of psychiatry at the University of Pennsylvania School of Medicine and author of several books on bipolar, depression and related topics.
It’s not surprising that misdiagnoses frequently occur. The Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV), doesn’t distinguish between bipolar and unipolar depression. Rather, a bipolar diagnosis is made based upon whether the person has experienced mania or hypomania.
“Bipolar depression looks very similar to major depression, with no distinct features,” says McIntyre. “That being said, people with bipolar depression more often complain of symptoms that are atypical for unipolar depression, including increased eating, sleeping, and profound reduction in energy. Moreover, people with bipolar depression also frequently complain of seasonal worsening and ‘therapeutic misadventures’ with antidepressants—that is, the depression gets worse with antidepressant therapy.”
Because bipolar and unipolar depression can “look” so similar, psychiatrists must take care to get detailed family histories—and to ask patients if they have ever experienced symptoms of mania or hypomania, says Eric D. Caine, MD, chairman of psychiatry at the University of Rochester Medical Center and an international expert on suicide prevention. Otherwise, “the tendency is to treat it as if it’s unipolar depression, with antidepressants alone, which may serve as rocket fuel for a manic episode,” he adds.
HOW IT FEELS
How does one experience bipolar depression? That depends upon whom you ask. Many people undergo distinct periods of stability, mania, and depression. Yet other individuals can feel both depressed and manic at the same time—simultaneously feeling very sad and energized.
Holly A. Swartz, MD, associate professor of psychiatry at the University of Pittsburgh School of Medicine, says it is relatively rare for people to meet the DSM-IV criteria for a mixed state, which requires a major depressive episode and a manic episode nearly every day for at least one week. “However, individuals meeting diagnostic criteria for either a depressive episode or a manic episode often have a few subsyndromal symptoms of the opposite pole of the disorder that co-occur with their predominant mood episode,” Swartz says. “For example, someone will meet full criteria for a depressive episode but will also have racing thoughts.”
Rapid-cycling—as defined by the DSM-IV diagnostic criteria—is having at least four distinct episodes of major depression, mania or hypomania, or mixed symptoms within a 12-month period. But it is possible to experience more than one rapid-cycling episode a week, or “even within one day,” according to the National Institute of Mental Health.
