Features of Depression in Schizophrenia

Objectives: This study examined the features of depression in different categories of schizophrenic patients as classified by both duration and ICD-10 course pattern. Methods: 385 schizophrenic patients were recruited from the Institute of Psychiatry Ain Shams University and Al Abassia Ministry of Health hospital, Cairo, Egypt. All cases were subjected to a Structured Clinical Interview for Diagnosis, section for schizophrenia and depression, socio demographic sheet, medical history sheet, Calgary Depression Rating Scale (CDRS), and Positive and Negative Symptoms Scale (PANSS). The studied sample was classified according to the schizophrenia duration to two groups: acute and chronic; and according to the schizophrenia course to three groups: continuous course, episodic course, and remittent course. Depression was categorized into three groups: patients with major depressive disorder (SDD), patients with depressive symptoms (SDS), and patients with no depression (ND). Results: Depression was found, in order of prevalence, as SDD, ND, and SDS. Depression was significantly associated with chronic duration and continuous course. Self depreciation was the most characteristic depressive symptom of acute schizophrenia, and hopelessness was the most characteristic one of chronic schizophrenia. No correlation between depressive and psychotic symptoms was found in acute schizophrenia; however, in chronic schizophrenia depression was correlated to all psychotic symptoms except positive ones. Factor analysis failed to specify selective subsets of PANSS symptoms associated with depression. Canonical discriminate analysis proved that CDRS is valid in classification of depression categories. Conclusion: Schizophrenia should be properly categorized in order to study its depressive features. Duration rather than course of schizophrenia is a risk factor for depression in schizophrenia.