Abstract
Background: While negative symptoms are a significant barrier to successful recovery in patients with schizophrenia, their pharmacotherapy by adjunctive antidepressants has produced unpredictable results.
Objective: In the present study, some of the native methodical published studies have been the subject of a new meta-analysis to evaluate the usefulness of add-on antidepressants on negative symptoms of schizophrenia.
Method: Following searching in known databases, eight homemade relevant randomized clinical trials, including 277 male participants, had been selected. All the samples had been chosen among the chronic male inpatients, meeting the diagnosis of schizophrenia according to Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revision, who had been entered into parallel group, double-blind studies for random assignment to an antidepressant or placebo plus their current antipsychotic. Scale for Assessment of Negative Symptoms was used as the primary outcome measure in these experiments for assessment of negative symptoms. Response, too, was defined as a reduction of ≥20% in the score of the aforesaid scale (total and/or subscales).
Results: Combined Effect Size of the aforesaid studies has revealed a significant influence with regard to the effectiveness of antidepressants on negative symptoms of schizophrenia (OR = 7.00, CI= 3.79 - 12.93, z= 7.49, p<0.000). Comparable consequences too could be found with regard to different symptoms of deficit syndrome. Anhedonia -Asociality displayed the best Combined Effect Size, followed by Affective Blunting, Avolition -Apathy, Attention Deficit, and lastly Alogia. Heterogeneity of all the abovementioned analysis was negligible and thus suitable.
Conclusion: Antidepressants have favorable effects with respect to the improvement of deficit syndrome and its different symptomatic dimensions.
Keywords: Schizophrenia, negative symptoms, deficit syndrome, adjuvant antidepressants, noradrenergic antidepressants, serotonergic antidepressants, pharmacotherapy.
Graphical Abstract