According to the APA (DSM-5, 2013), bipolar disorder involves both depressive and manic (and/or hypomanic) symptoms; as such, it is neither precisely a depressive disorder nor an anxiety disorder (the DSM classifies it under "Bipolar and Related Disorders"). However, extrapolating from the research literature on depression and anxiety, what would be the most reasonable inference to draw about a relationship between bipolar disorders and stress?