In this presentation, these questions will discussed:
1. Is there really such a disorder or is it just an illusion because of the observers' getting insufficient information?
2. What are the methodological criticisms upon the available data?
3. Is unipolar mania a rare condition?
4. Does it occur in different rates in different cultures?
5. If there is such a disorder what are the reliable criteria of it? Is it a stable diagnosis?
6. Even if such a disorder exits, is it so different from bipolar disorder to be considered a distinct nosological entity ?
7. What our future strategy should be to solve this problem?

The main criticisms upon the studies on unipolar mania as such:
1. The past depressive episodes, especially mild ones, may not have been assessed.
2. The patients may not have been followed-up long enough to see the future depressions.
3. Unipolar mania has generally been defined as the presence of manic episodes when there is no depressive episode. However, there is no consensus about the minimum number of mania, the minimum duration of illness or the exclusion criteria. Therefore, the different authors have used different criteria.

In spite of the above limitations, the available data in general and the more reliable recent studies suggest that there is a 'real' unipolar mania group that is about 1/5-1/6 of the bipolar patients.

Many of these studies are from nonwestern cultures and some of the reported rates are much higher than those in western studies. This conclusion arises the question of the relationship of unipolar mania and the culture. However, the methodological limitations of the studies leave this question open for the future investigations, at present.

Previous studies are generally based on the presence of 1 or 2 manic episodes with uncertain illness durations. Recent studies, on the other hand, have used at least 3 or 4 manic episodes, and minimum 4 years of illness as inclusion criteria. Some data suggest that the criteria of minimum 4 manic episodes and 4 years of illness duration may be pretty reliable and stable frame for unipolar mania diagnosis.

However, above all these considerations, the crucial question may be whether this diagnosis has a clinical importance? In another words, does it have any important characteristics different from classical bipolars? The available studies show that unipolar mania has more grandiosity, total episode number, psychotic symptoms, premorbid hyperthymia; and less rapid cycling and suicidality. May be the most important point is that unipolar manic patients seem to respond lithium prophylaxis poorly than bipolar patients do.

Do these differences make unipolar mania a distinct entity? I think we cannot say this at the moment. However, it is obvious that unipolar mania has received very less attention compared to unipolar depression or bipolar disorder. There is only a handful studies on this topic that are mostly from the nonwestern countries. For the future perspective, we can propose that it should be a course specifier of bipolar disorder. With this approach, we can hope an accumulation of standardized data that can stimulate the studies to solve the question.