Perhaps you feel that you are quite alone in suffering from this disorder, however bipolar disorders are relatively frequent. If one considers all various bipolar disorders together, the frequency (lifetime prevalence) is at 3.0% to 6.5%. The prevalence of bipolar I disorder is at 0.5% to 2.4% and bipolar II disorder at 0.2% to 5%, i.e. around 5% of the population are affected. Related to a city like Hamburg consequently around 18,000 to 70,000 people suffer from a bipolar mood disorder, related to Germany around two million people are affected. The age of first onset of the disorder in most people is between the 17th and 21st year of life, some symptoms or until then not recognised as such or weakened phases are however often perceived earlier at least already in adolescence (as from around the 15th year of life). 60 % of persons afflicted report the onset of the first symptoms already before the 18th year of life. After the 40th year of life, the first-time onset of a bipolar mood disorder is rather rare.