The new diagnostic category in the Depressive Disorders chapter of DSM-5 entitled 'Major Depressive Disorder With Mixed Features' is applied to individuals who meet criteria for Major Depressive Disorder and have concurrent subsyndromal hypomanic or manic symptoms. But the operational definition of this new specifier is much closer to that of hypomania and mania than to the definition of atypical depression or the older 'mixed depression.' Moreover, multiple studies have shown that the characteristics of individuals with this condition and the clinical trajectory of their illness is much closer to that of bipolar patients than to that of depressed individuals without comorbid hypomanic or manic symptoms. Thus we believe that this condition would be more appropriately placed in the Bipolar Disorders chapter of DSM-5. We also believe that this blurring of the depressive disorder- bipolar disorder boundary is one cause for the low inter-rater reliability in the diagnosis of Major Depressive Disorder.
DSM-5抑郁障碍一章中有一新的诊断类别为“伴 混合特征的重性抑郁障碍”，指的是符合重性抑郁障 碍的诊断标准并伴有亚综合征的轻躁狂或躁狂症状的 患者。但是这一新类别的操作定义相比较于非典型抑 郁症或过去“混合性抑郁症”的定义更加接近于轻躁 狂和躁狂症。而且，多项研究表明，这类患者的特征 和他们疾病的临床转归更接近于双相障碍患者，而不 同于不伴有轻躁狂或躁狂症状的抑郁症患者。因此， 我们认为，将这种情况归类于DSM-5的双相障碍更为 恰当。我们还认为，这种抑郁障碍– 双相障碍之间的 界线模糊不清是产生重性抑郁障碍诊断信度低的原因 之一。
Keywords: DSM-5; bipolar disorder; depression with mixed features; major depressive disorder; mixed depression.