Bipolar one, bipolar two, bipolar two and half, bipolar spectrum, and now for something entirely different

The case for a new diagnosis of cyclical mood disorder NOS.

 To the editor:  We have read the February 2006 edition focusing on the “Problems in the treatment of Bipolar disorder” with great interest.  One of the major issues in both study and clinical treatment is making a meaningful diagnosis.  This was touched upon in the editorial by Swann and in the research article of Perlis, et. al which compared features of unipolar to bipolar disorders.  However, we believe that there is a strong need for a new diagnosis, cyclical mood disorder, which captures a substantial number of patients who present with highly recurrent unipolar symptoms but respond poorly to antidepressants and preferentially to mood stabilizers.

There are three major reasons for the need for a new diagnosis.  The first is the poor response to treatment.  These patients based upon DSM IV criteria should only be diagnosed with major depressive disorder.  Non-psychiatric providers, following evidenced based protocols would be forced to go through innumerable futile or worse trials of antidepressants.  The second reason is stigma.  Even if a reliable diagnostic genetic marker were identified for bipolar disorder, this would stigmatize patients who have never manifested symptoms of mania.  This discrimination is currently evident in the Connecticut Bar Association’s, application that specifically asks applicants if they have ever been diagnosed with Bipolar disorder.  Internal medicine avoids stigma in several conditions by recognizing early syndromes as distinct from their more severe illnesses. For example patients with impaired glucose metabolism might be treated to prevent diabetes but are not given that diagnosis.

Finally, the validity of research studies necessitates accurate diagnosis.  The entrance of cyclical mood disorder patients into unipolar depression trials, unfairly introduces a bias against active treatment.  It may be the reason for failure of most medication trials in adolescent depression.  Early intervention with a mood stabilizer to a depressed young person may avert the appearance of bipolar symptoms and hopefully the associated morbidity and stigma.

We propose the neutral term “cyclical mood disorder, NOS” since it neither implies unipolar or bipolar diathesis.  Symptoms would include all the current criteria for major depression but have the additional criteria of a certain number of prior episodes.  These episodes might include subsyndromal episodes and have the frequency indexed according to age.  For example an adolescent may only require 2-3 episodes in two-year period, while a 30 year old require 5-10 episodes.  Research analysis can be done to choose an appropriate cut off frequency.  Ancillary criteria would include family history of bipolar, poor response to antidepressants without a mood stabilizer or “poop-out” of antidepressants after several months of good response with adequate dosage, prominence of atypical symptoms and energy dsysregulation.

We hope that introduction of this new diagnosis should inspire new research and advance clinical treatment.  Since it represents a reclassification of already diagnosed patients, it should avoid criticisms of creating diagnoses in to expand a population needing treatment.