WASHINGTON – A sea change is underway in how major depressive and bipolar disorders are diagnosed and treated.
Historically, the absence of an accurate, comprehensive nosology of depression has led to much suffering and confusion. People with bipolar disorder in particular are either not diagnosed early enough or are not diagnosed with the correct “flavor” of depression, according to Roger S. McIntyre, MD, author of updated treatment guidelines for bipolar depression, and the first-ever treatment guidelines for mixed features in major depressive disorder. “Twenty years ago, we would have described bipolar as episodic breakthroughs of mania and depression, with well intervals in between,” Dr. McIntyre said at Summit in Neurology & Psychiatry. “But now, we’ve really changed our fundamental thinking about bipolar disorder.”
Dr. Roger S. McIntyre
Although reasons for the evolution in thinking are many, one of the strongest currents of change flows from the 2013 publication of the DSM-5, according to Dr. McIntyre, professor of psychiatry and pharmacology at the University of Toronto, and head of the Mood Disorders Psychopharmacology Unit at University Health Network in Toronto.
“The DSM-5’s authors took a neo-Kraepelinian view that mood disorders are dimensional,” Dr. McIntyre said in an interview. As a result, there’s been a reversal of what he called the “social construct imposed upon the cosmos of mood disorders by the DSM-III that divided that world into either depression or bipolar disorder.”
This return to thinking of mood disorders as existing on a continuum, as psychiatrist Emil Kraepelin, MD, theorized around the turn of the last century, pivots on the decision to do away with mixed states and to instead add the mixed features specifier.
“The move to mixed features is the necessary bridge between bipolar disease and major depressive disorder,” Dr. McIntyre said in the interview.
Therefore, for a period of time between the 1980 publication of the DSM-III and the DSM-5, “real-world” presentations of subsyndromal, opposite-pole symptoms that are common in major depressive disorder (MDD) and in bipolar disorder were not accounted for.
In practical terms, the addition of mixed features means that a patient with mania who presents with subsyndromal depressive symptoms would be seen, for example, to have mania with mixed features. A patient with a depressive episode who presents with subsyndromal hypomanic symptoms would be seen to have depression with mixed features. Therefore, depression with mixed features can be present not only in MDD, but in both bipolar I and II.
New treatment algorithms
This dimensional approach of assessing mixed features along a continuum could lead to better and earlier diagnosis of bipolar depression and more targeted therapies, according to Dr. McIntyre. What he thinks it won’t do is lead to an overzealousness in the overdiagnosis of bipolar depression.
“That is false. We wouldn’t say we’re not going to diagnose bowel cancer because we hear it’s overdiagnosed. But to get the diagnoses right, what we need is fidelity to diagnostic criteria.”
Enter the state of Florida. As part of its best practices for psychotherapeutic use in adults, Florida is the first state to have published evidence-based guidelines for depression with mixed features. Dr. McIntyre is one of the guidelines’ coauthors.
Antidepressants bad, olanzapine worse
Some changes to treatment algorithms might come as a surprise. Despite being among the most commonly prescribed treatments for bipolar disorder, monotherapy with antidepressants is not approved in the guidelines. “Period,” said Dr. McIntyre. “Many patients do well on antidepressants, but the most common outcome is inefficacy.”
It might be better to combine an antidepressant with an atypical antipsychotic, or a mood stabilizer to avoid treatment-emergent mania, or, more commonly, destabilization in patients who are susceptible to subsyndromal mania, he said.
In addition to mitigating symptoms of a depressive episode, atypicals can help suppress hypomanic symptoms. Dr. McIntyre said this is critical to remember, because patients with these combinations of symptoms are “the very persons who shouldn’t get an antidepressant but are also the ones most likely to be prescribed them,” according to old ways of thinking.
As for maintenance in bipolar disorder, Dr. McIntyre believes the axiom, “What gets you well keeps you well,” is a good rule of thumb when going through the algorithm. “It’s not always true, but it’s almost always true.”
Management of MDD with mixed features includes the introduction of atypicals or mood stabilizers such as lithium or lamotrigine in patients with any prior history of hypomania or mania, something Dr. McIntyre said already is beginning to happen in practice.
Olanzapine monotherapy as a first-line treatment of bipolar disorder initially was “demoted” by Dr. McIntyre and his coauthors in Florida’s bipolar treatment guidelines. In the updated version, the atypical remains a second-line therapy behind lurasidone as the recommended first-line therapy because of olanzapine’s tendency to interfere with metabolic processes. Quetiapine also is a first-line therapy, but with the qualification that it, too, could interfere with metabolic processes. Combination therapy with olanzapine plus fluoxetine is second-line.