Related Experiment Video
Updated: Sep 30, 2026

Association Between Sleep Quality and Cognitive Symptoms in Patients with Major Depressive Disorder
Published on: April 26, 2024
Depression in paranoid and nonparanoid schizophrenic patients compared with major depressive disorder
Carmie L Candido1, David M Romney
1Hull Child and Family Services, 2266 Woodpark Avenue SW, Calgary, Alberta, Canada T2W 2Z8. c.candido@wrhull.com
Background:
Depression occurring in schizophrenia is a common problem; however, investigators have typically not studied it with the paranoid/nonparanoid dichotomy in mind. This study examines the quality as well as the severity of depression in three psychiatric groups: paranoid schizophrenia patients, nonparanoid schizophrenia patients, and nonpsychotic major depression patients.
Method:
Clinical and sociodemographic data were collected on 27 paranoid and 27 nonparanoid schizophrenia patients during their postpsychotic phase while they were at least mildly depressed, and a comparison group of 27 nonpsychotic patients diagnosed with major depressive disorder. The three groups were then assessed on various psychometric scales for severity of depression, profile of symptoms, suicidal risk, and anhedonia.
Results:
The paranoid schizophrenia patients were more depressed and more at risk for suicide than the nonparanoid schizophrenia patients, yet their depressive profiles and levels of anhedonia were similar.
Conclusions:
Depressed mood and anhedonia constitute serious problems for schizophrenia patients, but particularly for paranoid schizophrenia patients during the postpsychotic phase of their illnesses.
Clinical Implications:
Schizophrenia patients, especially those with the paranoid features, should be routinely evaluated and monitored for depression. Apart from treatment with drugs, cognitive therapy may be considered a viable option, particularly for paranoid schizophrenia patients.
Limitations:
Gender was not matched for the two schizophrenia groups and extrapyramidal side effects were not measured.
Related Concept Videos
Personality Disorders: Paranoid and Schizoid
Paranoid Personality Disorder
Paranoid personality disorder is...
Depressive Disorders: MDD and Dysthymia
Negative and Cognitive Symptoms of Schizophrenia
Negative Symptoms
Negative symptoms of schizophrenia manifest as deficits in normal emotional and behavioral functioning, profoundly impacting daily life. Individuals with schizophrenia often display a flat affect, characterized by a near-total absence of emotional expression,...
Depression: Overview
Depressive Disorders: Etiology
Biological Factors in Depression
Biological predispositions significantly influence the risk of developing depressive disorders. Genetic studies highlight the role of variations in the serotonin transporter...
Positive Symptoms Schizophrenia: Hallucinations and Delusions
Hallucinations
Hallucinations in...