Differences between chronic and nonchronic depression: Systematic review and implications for treatment

Abstract

Background: There is still uncertainty if and to what extent chronic depression (CD) presents with specific features especially in contrast to the nonchronic course of major depressive disorder (non-CD). This systematic review aims to summarize the existing literature regarding sociodemographic factors, psychopathology, and course of disease in patients with CD in comparison to patients with non-CD. Methods: A structured database search (MEDLINE, PsycINFO, Web of Science, CENTRAL) was performed. All studies comparing CD with non-CD patients were included. Twenty-eight studies, including cohort studies, cross-sectional studies, and observational studies, were identified in which both subgroups were diagnosed according to DSM-IV or DSM-5, respectively. Primary outcome were group comparisons focused on sociodemographic factors, childhood adversity, onset of the disorder, comorbidities, severity and course of the depressive symptoms, and specific psychopathology.Results: Patients with CD had an earlier onset of depressive symptoms, higher rates of psychiatric comorbidities, and a complicated treatment course (e.g., higher rates of suicidality) compared to non-CD. We also found some evidence for specific features in the psychopathology of CD patients (submissive and hostile interpersonal styles) in contrast to non-CD patients. Results were inconsistent with regard to childhood maltreatment. No differences were found regarding the severity of depressive symptoms and most sociodemographic factors. Conclusion:Despite some inconsistencies, the results of this review verified important differences between CD and non-CD. However, future research is needed to characterize especially the specific psychopathology of CD in comparison to non-CD patients to develop more tailored treatment strategies. K E Y W O R D Sassessment/diagnosis, clinical trials, depression, dysthymic disorder, mood disorders 18

Persistent depressive disorder across the adult lifespan: results from clinical and population-based surveys in Germany

“…On the individual level, there was a remarkably higher prevalence of current depressive symptoms (as assessed by PHQ-9) among PDD cases than among NCMDD cases, as well as a higher mean number of depressive episodes (irrespective of episode severity or duration). Furthermore, higher levels of psychological and somatic comorbidity are in line with international findings on higher comorbidity rates [12,14,15,18,20,22] and somatic morbidity [14,15] for chronic depression courses. The present outcomes of worse self-rated health and reduced health-related quality of life for the MCS correspond to previous findings of reduced psychological well-being and health-related quality of life for individuals with chronic depression [12][13][14]23].…”

“…Recent reviews found that patients with PDD more often have psychiatric comorbidities than those with non-PDD, particularly personality disorders but also axis I and somatic comorbidities [22]. However, differences between PDD and NCMDD cases in DEGS1-MH have only been observed by trend, and our clinical sample of PDD patients demonstrated even less comorbidity than interview-defined cases.…”

“…Furthermore, the average duration of past inpatient treatment is longer for PDD cases [53]. Patients with PDD also have higher rates of suicidal attempts and suicidal thoughts and are more likely to have a higher frequency of treatment approaches in general and a longer disorder duration [22].…”

“…Similarly, international findings are heterogeneous: one meta-analysis found a significant relationship between early onset of depression and chronicity of the disorder [54]. However, in a recent review of 17 studies directly comparing age of onset in PDD vs. non-PDD cases, half the studies reported earlier onset for chronic vs. non-chronic depression whereas the other half reported no difference [22].…”

“…Furthermore, chronic depression may have an earlier onset (before 21 years of age) [14,[20][21][22] and worse outcomes than non-chronic depression, such as single or recurrent depressive episodes with full inter-episode recovery. Chronic depression is characterized by higher comorbidity rates [12-15, 18, 20, 22], somatic morbidity [14,15], suicidality [14,20,22], reduced somatic and psychological well-being and health-related quality of life [12][13][14]23], lower employment rates [24], longer delays for treatment [15], and limited effects of psychotherapeutic or psychopharmacological treatment [10,11,13,[25][26][27], all of which indicate its enormous direct and indirect costs.…”