Authors' reply

Although the underdiagnosis of bipolar disorder remains a fact, Dr Gangdev makes the valid point that there are very few advocates for those wrongly diagnosed as having bipolar disorder and mentions that temperament and vegetative lability should not be considered pathological.

This is in full agreement with the spectrum concept presented in my editorial: temperament and hypomanic symptoms per se are variations within the normal range. It would therefore be wrong to diagnose bipolar II disorder in a person with major depression and a cyclothymic temperament. Although a cyclothymic temperament is a correlate of bipolar disorder, many people with such a temperament may develop only depression. However, this is again a hypothesis which must be tested in prospective community studies. In 1921 Kretschmer distinguished clearly between cyclothymic temperament as a normal trait and cycloid personality, which was a pathological state of mood swings (corresponding to a personality disorder in current terminlogy).

Dr Gangdev hopes that phenomenology will bring about the necessary progress. Our Zurich Study interview, which included 30 symptoms of depression, was unfortunately unable to find any qualitative differences between the symptom profiles of bipolar II depression and unipolar major depression. Phenomenology may not be able to solve the diagnostic problem of bipolar II disorder. Moreover, both the Mood Disorder Questionnaire (including 20 symptoms of hypomania) and the self-assessment Hypomania Checklist–32 (with 32 symptoms)) demonstrated only a continuum between high scores within the normal range and pathological hypomania.