The inflammatory subgroup of major depression

Major depression remains one of the leading causes of disability and suicidality worldwide. A key reason for the inadequate effectiveness of many treatments is their marked biological and clinical heterogeneity. The available evidence indicates that chronically increased inflammatory activity is a key pathophysiological mechanism in a relevant proportion of those affected. This inflammatory subgroup shows characteristic biomarker profiles, specific symptom clusters, a particular interaction with neurotransmitter systems and a differentiated response to forms of therapy. The precise characterization of this subtype can make a decisive contribution to the further development of targeted, mechanistically based personalized psychiatry.