CME
Bipolar Disorder
CLINICAL STATES AND COURSE SPECIFIERS: IMPLICATIONS FOR TREATMENT
Bipolar disorder can manifest with a variety of clinical presentations along the course of a lifetime. There is growing evidence that the course or symptoms of bipolar disorder, particularly the presence of rapid cycling or mixed states, has major clinical significance. Rapid cycling and mixed states are associated with an increased risk of suicide and substance use. There is some evidence that patients with rapid cycling do not respond as well as others to a variety of medications, but there is now evidence for the effectiveness of a number of compounds, including divalproex, olanzapine, and quetiapine in patients with rapid cycling. The presence of psychosis during a manic or depressive episode indicates severe illness and usual requires combination therapy with a mood stabilizer and a second-generation antipsychotic.
There is significant evidence that monotherapy with a mood stabilizer over a lifetime is sufficient to maintain long-term wellness in only a minority of patients. Hence, classifying the bipolar disorder into specific "sub-types", like mixed states, rapid cycling and or psychosis, at different points in the course of the illness may allow more specific choices of biological treatment.
Classical Bipolar I with three or fewer cycles per year runs a less turbulent course than bipolar disorder with rapid cycling, and responds very well to lithium, although it also responds to divalproex (DVPX), carbamazepine (CBZ), and second-generation antipsychotics. Many medications are more effective in preventing manic than depressive relapse, though lithium, divalproex, lamotrigine and quetiapine all have evidence for efficacy in preventing depression also. Mixed states should be screened for in every mania and depression, evidence suggests that they are more common than previously thought. Mixed states respond to DVPX or CBZ, with a relatively poorer response to Lithium. As rapid cycling and mixed states can sometimes be precipitated by antidepressants, these medications should routinely be discontinued.
Bipolar II Disorder has not been studied as thoroughly as Bipolar I Disorder, but recent studies have demonstrated efficacy for quetiapine in treating acute depression and preventing mood episodes during long-term treatment. The evidence base for other medications is more limited, but lithium, lamotrigine, divalproex, or any of these medications in combination with an antidepressant can also be considered treatment options.