Within this framework, it should also be pointed out that even higher plasma BDNF levels were previously observed in MDs and related syndromes such as in depressed patients [19], in BDNF Met carriers with chronic depression [42], in patients with a mixed-state episode compared with patients with a depressive episode [43], in treatment-resistant BD patients displaying high interleukin-1β [44], in pain perception disturbances [45] and in adjustment disorders [46]. The gene discussed is BDNF; the disease is adjustment disorder.