Schizoaffective disorder is a complex psychiatric illness in which psychotic and mood symptoms occur simultaneously. Both symptoms specific to schizophrenia, such as delusions and hallucinations, and findings related to mood disorders, such as major depression or manic episodes, are observed in the same individual.

For this reason, the disorder is situated at the intersection of both psychotic disorders and mood disorders. First described in 1933 by Jacob Kasanin, this clinical presentation has long been a subject of debate in psychiatry due to the diagnostic difficulties it creates and its heterogeneous symptom structure.

DSM-5 Diagnostic Criteria for Schizoaffective Disorder

According to DSM-5, the following conditions must be met for the diagnosis of schizoaffective disorder:

• A major mood episode (depressive or manic) must occur together with at least two symptoms specific to schizophrenia, observed continuously for at least two weeks (for example: delusions, hallucinations, disorganized speech, catatonic behaviors, negative symptoms).
• Psychotic symptoms must persist for at least two weeks without mood symptoms.
• Mood symptoms must be present during the majority of the active and residual phases of the illness.
• Symptoms must not be attributable to substance use or another medical condition.

These criteria play a critical role in distinguishing schizoaffective disorder from bipolar disorder or schizophrenia. Establishing the diagnosis requires careful observation based on timelines and detailed clinical evaluation.

What Are the Symptoms of Schizoaffective Disorder?

The symptoms of schizoaffective disorder manifest in both mood and psychotic dimensions. Although the distribution of symptoms varies from person to person, they are generally grouped as follows:

Psychotic Symptoms: Delusions (for example: being followed, thought reading), hallucinations (most often auditory), disorganized thought and speech, bizarre behaviors, catatonia and negative symptoms (social withdrawal, blunted affect).

Mood Symptoms: Major depressive episode (low mood, anhedonia, guilt, suicidal ideation) and/or manic episode (euphoria, insomnia, excessive speech, distractibility, risky behaviors).

These two groups of symptoms may emerge simultaneously at times and sequentially at other times. Due to the fluctuating course of symptoms, the diagnostic process may take time.

What Are the Causes of Schizoaffective Disorder?

The etiology of schizoaffective disorder has not yet been fully clarified; however, the existing literature emphasizes the interaction of genetic, neurobiological and environmental factors.

Genetic predisposition is the strongest risk factor. Individuals with a family history of schizoaffective disorder have a significantly increased likelihood of developing the illness. Twin studies have shown that the heritable component of schizoaffective disorder is at a level similar to that of schizophrenia and bipolar disorder.

Neurobiological factors include dysregulations in the dopamine and glutamate systems. Hyperactivity of the mesolimbic dopaminergic pathway is thought to contribute to psychotic symptoms, whereas dopamine deficiency in the frontal cortex is associated with negative symptoms. Additionally, disturbances in serotonergic and noradrenergic systems have been linked to mood fluctuations.

Environmental factors include childhood trauma, parental loss, social exclusion, substance use (particularly cannabis), migration, early urban life and low socioeconomic status. Prenatal infections and perinatal complications may also affect brain development and increase disease risk.

Risk Factors for Schizoaffective Disorder

The risk factors contributing to the development of schizoaffective disorder result from the combination of genetic vulnerability and environmental stressors. Knowledge of these factors is crucial for prevention and early intervention.

Genetic factors are among the primary risk elements. Individuals with first-degree relatives diagnosed with schizophrenia or bipolar disorder have a significantly increased risk of developing schizoaffective disorder. Genetic research indicates that this disorder shares genetic commonalities with both schizophrenia and mood disorders.

Prenatal and early neurodevelopmental factors, such as prenatal infections, maternal stress, perinatal hypoxia and low birth weight, may affect central nervous system development and contribute to risk.

Childhood trauma, particularly adverse experiences such as emotional neglect, physical or sexual abuse, may predispose to psychopathology later in life. Early parental loss, insecure attachment patterns and family conflicts have also been associated with the development of the disorder.

Psychosocial stressors, such as migration, social exclusion, economic deprivation and loneliness, may trigger schizoaffective symptoms particularly in individuals with genetic vulnerability.

Substance use, especially frequent and heavy use of cannabis, amphetamines or hallucinogens during adolescence and young adulthood, may initiate or exacerbate psychotic symptoms.

Gender and age may also influence illness risk. Some studies have reported that depressive symptoms predominate in women, while psychotic symptoms tend to be more severe in men. The illness usually begins later in women, whereas it tends to appear earlier in men.

It is accepted that these risk factors operate in a multidimensional interaction; thus, it is not possible to explain the illness with only a single factor. Identifying individuals at risk at an early age and directing them to preventive mental health services play a critical role in preventing or mitigating the disorder.

How Is Schizoaffective Disorder Diagnosed?

The diagnostic process requires a detailed psychiatric evaluation. Based on DSM-5 criteria, the timing and co-occurrence of symptoms are carefully examined.

Psychotic symptoms must occur both together with and separately from mood symptoms. Therefore, the patient must be observed for at least several weeks for diagnostic purposes. The most important factor complicating the diagnosis is the variability of symptoms over time.

In the differential diagnosis, bipolar disorder, major depression with psychosis, schizophrenia and substance-induced psychotic disorders must be ruled out. If necessary, auxiliary tests such as brain imaging (MRI), laboratory tests, thyroid functions and toxicology panels may be employed.

How Is Schizoaffective Disorder Treated?

The treatment of schizoaffective disorder requires a holistic approach that targets both psychotic and mood symptoms. Long-term follow-up and an individualized intervention plan are important.

1. Pharmacotherapy

The foundation of treatment consists of antipsychotics and mood stabilizers.

• Antipsychotics: Used to control psychotic symptoms. Atypical antipsychotics (for example risperidone, olanzapine, aripiprazole) may be effective on both positive symptoms and mood symptoms.
• Mood stabilizers: Agents such as lithium, valproate and lamotrigine are preferred in the management of manic or depressive episodes.
• Antidepressants: In severe depressive episodes, SSRI or SNRI medications may be added cautiously, considering the risk of exacerbating psychosis.

The treatment plan is organized according to the type of symptoms and updated through regular psychiatric evaluations.

2. Psychotherapy and Psychoeducation

Psychological interventions that support pharmacological treatment have a significant impact on the course of the illness:

• Cognitive Behavioral Therapy (CBT): Strengthens reality testing and enhances functioning.
• Psychoeducation: The patient and family are informed about the nature of the illness, relapse signs and treatment adherence.
• Social Skills Training: Supports participation in social life, particularly in individuals with prominent negative symptoms.

3. Family Support and Community-Based Interventions

Family members being informed about the illness strengthens the treatment process. Recognition of early warning signs increases the capacity to intervene during crises. Community mental health centers, supported employment and rehabilitation programs may enhance the individual’s social functioning.

Impact on Daily Life and Prognosis

Schizoaffective disorder may negatively affect quality of life and social functioning. The illness may follow an episodic course with relapses, or in some individuals, it may progress chronically with low levels of functioning.

Cognitive impairments, social withdrawal, lack of motivation and functional decline are frequently observed. Educational life may be interrupted, maintaining continuity in employment may become difficult. Deterioration in social relationships, loneliness and stigmatization are common problems.

Compared to schizophrenia, schizoaffective disorder may have a better prognosis; however, poor treatment adherence, substance use and the severity of psychotic symptoms are among the indicators of poor prognosis. The risk of suicide is high; careful monitoring is essential, especially during periods dominated by depressive symptoms.

Schizoaffective disorder is a complex psychiatric condition characterized by the coexistence of both mood and psychotic symptoms, with challenges in both diagnosis and treatment. Today, it is accepted that it is shaped by the interaction of biological, environmental and psychosocial factors. Early diagnosis, a holistic treatment plan and effective utilization of social support mechanisms may positively influence the course of the illness.