methods were used. Results. A high level of comorbidity of BAD with other mental disorders was identified -45.5%. It was shown that patients with index comorbidity during the first visit to a psychiatrist were diagnosed wrongly more frequently than patients suffering from BAD onlyin 69.6% and in 49.1%, respectively (p<0.05). In cases of combination of BAD with other mental disorders in comparison with "pure" BAD family history of mental disordersin 71.7% and 50% respectively; suicidal thoughts -69.6% and 40% respectively; mixed episodes in the course of BAD -71.7% and 45.5% respectively; number of suicidal attempts -2 [1; 3] and 1 [1; 1] respectively, as well as lesser (p<0.05) value of the index of cycling -0.8 [0.6; 1.5] and 1.4 [0.9; 2.3] respectively, were revealed more frequently (p<0.05). Thus, comorbid mental disorders affected the main clinical-dynamic indicators of BAD and heightened the risk of patients' suicidal behavior.