Comorbid anxiety and depression: Clinical and conceptual consideration and transdiagnostic treatment

Although anxiety and depression have been considered as two distinct entities according to the diagnostic criteria, anxious depression (comorbid anxiety and depression) is relatively a common syndrome. According to the DSM-5 criteria, it uses “with anxious distress specifier” to define anxious depression in its MDD section. Anxious depression is known to have different neurobiological profiles compared to non-anxious depression. Several studies have revealed significant differences between anxious depression and non-anxious depression regarding the hypothalamic-pituitary-adrenal (HPA) axis function, structural and functional brain imaging findings, inflammation markers, etc. Patients with anxious depression were significantly more likely to be found in primary care setting and more likely to be associated with female gender, non-single, unemployed, less educated, and more severe depression. Previous reports also showed that patients with anxious depression had more frequent episodes of major depression and a higher risk of suicidal ideation and previous suicide attempts than those with non-anxious depression. Although anxious depression is known to be associated with poor treatment outcomes in several studies, recent researches have sought to find better treatment strategy to improve patients with anxious depression.