As noted in recent courses as well as in Essentials of Abnormal Psychology, it is not uncommon for two or more disorders to coexist in the same person (Durand & Barlow, 2006). Consistent with said manual, an article published in the "Psychiatric Times" states: "Patients with BPD are at higher risk of developing many other subtypes of anxiety" (Sagman and Tohen, 2009). This is the case for the comorbidity of bipolar disorder and post-traumatic stress disorder. Bipolar disorder, a mood disorder, is identifiable by a “proneness to manic episodes in an endless roller coaster ride from the heights of elation to the depths of despair” (Durand & Barlow, 2006). A case report written by Dr. Stephen Salzbrenner and Eileen Conaway for the National Center for Biotechnology Information states that post-traumatic stress disorder, an anxiety disorder, is identifiable by "the patient's reliving of an extremely traumatic event, often potentially fatal. and is associated with symptoms of hyperarousal and avoidance of stimuli that remind the patient of said event” (2009). The overlapping symptoms of each disorder can often lead to difficulties when interpreting symptoms, treating these disorders, and resulting prognosis. According to the American Academy of Clinical Psychiatrists, research shows that between 16% and 39% of bipolar patients also have criteria for post-traumatic stress disorder due to the overlap in symptoms between the two disorders (2012). It is not entirely surprising that the American Academy of Clinical Psychiatrists further reports that high rates of post-traumatic stress disorder are seen in people diagnosed with bipolar disorder, as many people with bipolar disorder also have a history of bipolar disorder. article ......ps://www.aacp.com/Pages.asp?AID=10227 &issue=&page=&UID=#0212ACP_ Schaffer-tab3.Dilsaver, Steven C. (2010). How to treat PTSD in patients with comorbid mood disorders. Current psychiatry. Retrieved April 2, 2014 from http://www.currentpsychiatry.com/fileadmin/cp_archive/pdf/0904/0904CP_Article2.pdf.Durand, VM and Barlow, DH (2006). Essentials of Abnormal Psychology (6th ed.). Belmont, CA: Thomson/Wadsworth. Sagman, D. and Tohen, M. (2009). Comorbidity in bipolar disorder. Psychiatric time. Accessed April 2, 2014, from http://www.psychiatrictimes.com/bipolar-disorder/comorbidity-bipolar-disorder.Salzbrenner, Stephen. and Conaway, Eileen. (2009). Misdiagnosed bipolar disorder turns out to be post-traumatic stress disorder. National Center for Biotechnology Information. Retrieved April 1, 2014 from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2743211.