Relationship between Positive and Negative Symptoms of Schizophrenia and Psychotic Depression with Risk of Suicide

Objective: Suicide is one of the most important early causes of death in psychotic patients. The main object of this research was to determine the relationship between positive and negative symptoms of schizophrenia and psychotic major depressive disorder (MDD) with suicidal history and risk.

Methods: Sixty five patients with schizophrenia compared to 65 patients with psychotic MDD in a cross sectional study. Patients were evaluated using positive and negative syndrome scale (PANSS) (to measure severity of psychopathology) and the California risk estimator for suicide. Collected information were analyzed using SPSS 11/8 version by t-test, chi-square and ANOVA and Pearson correlation test.

Results: There was a significant relation between positive symptoms with suicidal risk and histories of suicidal attempts in patients with schizophrenia (r= 708, p<0.0001 and r= 0.55, p<0.0001 respectively). Negative symptoms also had a significant but reverse relation with suicidal risk and histories of suicidal attempts in this group (r= -0.529, p<0.0001 and r = -0.512, p<0.0001 respectively). There was a significant reverse relation between positive symptoms and suicidal risk in patients with psychotic MDD (r= -0.26, p<0.036). Negative symptoms did not have a significant relation with suicidal risk in this group. Also there was no significant relation between positive or negative symptoms and histories of suicidal attempts in MDD patients.

Conclusion: Positive and negative symptoms have different relationships with suicide in patients with schizophrenia and psychotic MDD.