Dysthymic disorder is a mood disorder consisting of chronic depression, with less severe but longer lasting symptoms than major depressive disorder. Since it’s less severe than depressive disorder often psychotherapy will be sufficient to treat this chronic. A recent Cochrane Library review found 17 placebo-controlled double-blind studies in DD, which generally have found significant differences favoring medication treatment form of depression although long term efficacy of treatment hasn’t been studied extensively.
the Cochrane reviewers concluded that drugs are effective in the treatment of DD, with no differences between and within the drug classes; however, that TCAs are more likely to cause adverse events and dropouts than other medication class
I’ve always admired placebo controlled trials since they do deliver the best evidence for efficacy of a treatment especially in depression. Antidepressants are often disqualified for not working only with severe depression. This is mostly due to bad trial design to my opinion. For that reason I want to present a recent placebo controlled trial with escitalopram for dysthymic disorder.
The authors conducted a 12 week, double blind, placebo controlled trial with escitalopram for dysthymic disorder. Of notice is the use of the Structured Clinical Interview for DSM-II Borderline Personality Disorder module beside other more appropriate depression scales. As the authors mentioned: to exclude suicidal patients which to me hardly seems a reason since other used scales also investigate suicidality.
Non of the primary outcome measures improved significantly after 12 weeks, response and remission did not significantly differ between groups.
All measures of depressive symptoms and psychiatric functioning showed a significant main effect of time, indicating that on average, both the groups showed improvement over time, regardless of treatment group.
Again a plausible result from a study well done. Nevertheless, on some secondary outcome measures some differences were significant. These were social and global functioning.
Hellerstein, D., Batchelder, S., Hyler, S., Arnaout, B., Toba, C., Benga, I., & Gangure, D. (2010). Escitalopram versus placebo in the treatment of dysthymic disorder International Clinical Psychopharmacology, 25 (3), 143-148 DOI: 10.1097/YIC.0b013e328333c35e