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.