Date of Award


Document Type

Scholarly Project

Degree Name

Master of Physician Assistant Studies (MPAS)


Physician Assistant Studies


brain-derived neurotrophic factor; sertraline; venlafaxine; venlafaxine hydrochloride; depressive disorder; serotonin and noradrenaline reuptake inhibitors; serotonin uptake inhibitors


Major depressive disorder (MDD) is a neuropsychiatric condition that is becoming increasingly prevalent in our country. According to Cai, Huang, and Hao (2015), MDD is “common and devastating” (p. 61) and has a very complex pathophysiology. Until recently, a definitive etiology had not been found, however, new evidence has suggested that Brain-derived neurotrophic factor (BDNF) and cognitive-emotional biomarkers may be a key into the mechanism of this disorder.

My literature review of articles found in PubMed, CINAHL, Cochrane Library, and PsychINFO within the last ten years focused on the hypotheses of the pathophysiology of MDD, cognitive-emotional biomarkers, and BDNF. The review found that MDD has a multitude of interconnecting systems that highlight its mechanism, and this is why it is so difficult to find a treatment option that works. However, cognitive-emotional biomarkers were able to predict the efficacy of certain antidepressants in the treatment of MDD. BDNF was also found to be decreased in patients with MDD and increased after treatment with certain medications. These systems may help predict better treatment response and an overall improvement of the burden of this disease.