Treatment-resistant depression

Abstract

Treatment-resistant depression is no different. It is a diagnosis that is often dreaded by patients, caregivers, and providers alike. It is responsible for increased hospitalizations, increased outpatient provider visits, greater use of psychotropic medications, and an average six times greater total healthcare cost incurrence compared to non-treatment-resistant depressed patients. Yet, the definition of treatment-resistant depression (TRD) remains somewhat controversial. In its simplest form, TRD can be defined as lack of significant improvement after two adequate trials of two different antidepressants from two different pharmacologic classes. However, the definition can quickly become quite complicated. According to Berlim, one can find more than 10 different definitions of TRD throughout the published literature. In addition, various authors have proposed staging systems for further description and characterization of TRD. Still others have argued that perhaps many instances of TRD actually represent undiagnosed bipolar disorder, nonadherence with therapy, and/or inadequate dose or duration of antidepressant therapy.