Persistent Depressive Disorder: Commentary on Parker and Malhi

Chronic vs non-chronic depression in psychiatric inpatient care - Data from a large naturalistic multicenter trial

BACKGROUND

Around 20% - 30% of depressed individuals experience a chronic form of depression lasting two or more years. This naturalistic study investigates the characteristics and the course of chronic depressed patients (CD) during standard antidepressant treatment in comparison to not chronically depressed (NCD) patients.

METHODS

Data of 954 patients were drawn from the prospective naturalistic, multicenter study of the German research network on depression, CD was met as classifier by 113 patients (11.8%), whereas 841 patients (88.2%) had non-chronic courses (NCD).

RESULTS

CD was significantly associated with a low age at onset, use of benzodiazepines, psychotherapy at baseline, substance abuse, a depressive personality disorder and a low degree of extraversion. CD patients showed a longer hospital stay, lower remission rates, increased rates of suicidal ideation as well as higher depression scores at discharge. In addition, individuals with chronic depression continued to obtain higher neuroticism scores and lower extraversion scores at discharge.

LIMITATION

Results were assessed by a post-hoc analysis, based on prospectively collected data.

CONCLUSION

CD patients have an inferior outcome in clinical measures as well as personality dimensions (i.e. low extraversion) compared to non-CD patients. These findings support the notion that CD patients entering a setting of standard psychiatric inpatient care will show less benefit compared to non-CD patients, and that this difference as such may be used as a stratifying marker for providing specialized psychiatric treatment with optimized pharmacological and psychotherapeutic protocols.

Review of dysthymia and persistent depressive disorder: history, correlates, and clinical implications

Persistent depressive disorder is a chronic mood disorder that is common and often more disabling than episodic major depression. In DSM-5, the term subsumes several chronic depressive presentations, including dysthymia with or without superimposed major depressive episodes, chronic major depression, and recurrent major depression without recovery between episodes. Dysthymia can be difficult to detect in psychiatric and primary care settings until it intensifies in the form of a superimposed major depressive episode. Although information is scarce concerning the cause of persistent depressive disorder including dysthymia, the causation is likely to be multifactorial. In this narrative Review, we discuss current knowledge about the nosology and neurobiological basis of dysthymia and persistent depressive disorder, emphasising a dimensional perspective based on course for further research. We also review new developments in psychotherapy and pharmacotherapy for persistent depressive disorder, and propose a tailored, modular approach to accommodate its multifaceted nature.