8 differences between schizoaffective disorder and schizophrenia

A summary to distinguish between schizoaffective disorder and schizophrenia.

Schizoaffective disorder and schizophrenia are two mental disorders that fall into the category of psychotic disorders. Psychotic disorders include two typical symptoms: delusions and hallucinations (although there are more).

These two disorders, although they have certain similarities, are quite different. But... what are the differences between schizoaffective disorder and schizophrenia? In this article we are going to know them.

Schizoaffective disorder and schizophrenia: what are they?

Before delving into the differences between schizoaffective disorder and schizophrenia, let's know what each of these mental disorders consists of.

1. Schizoaffective disorder

Schizoaffective disorder belongs to the group of psychotic disorders. That is, it is included in this category along with others such as schizophrenia or delusional disorder. Its prevalence is 0.3% of the population, according to the DSM-5 (Diagnostic Disorders Manual).according to the DSM-5 (Diagnostic Manual of Mental Disorders).

But what does it consist of? The DSM-5 diagnostic criteria for schizoaffective disorder include: meeting criterion A for schizophrenia (delusional ideas, hallucinations, disorganized language... for at least one month) and an uninterrupted period of illness during which a major depressive episode (necessarily including depressive mood) or a manic episode has occurred.

That is, in this case psychotic symptoms are combined with mood symptoms. In addition, it is necessary that for at least 2 weeks there have been no significant affective symptoms but delusions or hallucinations.

This disorder is somewhat controversial, since there are authors who consider it an independent disorder of schizophrenia, others who consider it as a variant of schizophrenia, and others as a variant of mood disorders. Finally, others believe that it is a transitional state between schizophrenia and mood disorders.

2. Schizophrenia

Schizophrenia is the "quintessential" psychotic disorder.. About 0.3 to 0.7% of the world's population suffers from schizophrenia, according to the latest edition of the DSM-5. It is a very disabling mental disorder, although there are interindividual variabilities, and with psychological and pharmacological treatment the disease can be brought under control.

Schizophrenia includes a series of symptoms such as: hallucinations, delusions, disorganized thinking and language, cognitive disturbances, abulia, depressive symptoms, flattened affect, etc. Hallucinations and delusions are classic psychotic symptoms, which can also appear in other disorders.They can also appear in other disorders of the psychotic spectrum beyond schizophrenia.

Specifically, the DSM-5 diagnostic criteria for schizophrenia include: characteristic symptoms such as those we have mentioned (hallucinations, delusions...) that must last at least 1 month, in addition to a socio-occupational dysfunction in the person's life and the presence of continuous signs of the disorder that must last at least 6 months (this includes the prodromal and residual period of the disease).

8 Differences between schizoaffective disorder and schizophrenia

As we have seen, schizoaffective disorder and schizophrenia are two independent disorders. Their fundamental difference is that in schizoaffective disorder, in addition to meeting criterion A for schizophrenia, the criteria for major depressive episode or bipolar depressive episode are met.

In addition to this, there are more differences between the two. So, without further ado, let's look at the 8 differences between schizoaffective disorder and schizophrenia:

1. Duration criteria.

The first of the differences between schizoaffective disorder and schizophrenia refers to the duration criteria.

The diagnostic criteria for schizophrenia require the occurrence of characteristic symptoms such as delusions and delusional ideas. characteristic symptoms such as delusions, hallucinations, disorganized language, etc., for at least 1 month (or longer).for at least 1 month (or less if the symptoms have been successfully treated). In addition, there must be continuous signs of the disorder for at least 6 months.

On the other hand, in schizoaffective disorder, the criteria include: the same monthly criterion of schizophrenia (minimum duration of one month of symptoms), but not the 6 months of schizophrenia. In addition, for schizoaffective disorder it is added that there must be 2 weeks without remarkable affective symptoms, but where delusions or hallucinations (psychotic symptoms) do appear (a criterion that is not included in schizophrenia).

2. Episodes/Mood Disorders

In schizophrenia a schizoaffective disorder is excluded for the diagnosis to be made. In addition, mood disorders are also excluded in this case.

In schizoaffective disorder, on the other hand, mood disturbances must be present in order for a diagnosis to be made, mood disturbances must be present for a diagnosis to be made (major depressive episodes or major depressive episodes). (major depressive episodes or manic episodes).

3. Subtypes

In the DSM-5 the subtypes of schizophrenia are deleted (in the DSM-IV-TR they were: paranoid, disorganized, catatonic, undifferentiated and residual schizophrenia, and in the ICD-10 simple schizophrenia was also included).

In contrast, schizoaffective disorder includes the following subtypes: bipolar type (if the disorder includes some manic episodes) and depressive type (if it includes major depressive episodes).

4. Prognosis

Another difference between schizoaffective disorder and schizophrenia refers to the prognosis of the disorder. Thus, the prognosis of schizoaffective disorder is better than that of schizophrenia (although worse than that of mood disorders).

5. Prevalence

While the prevalence of schizophrenia ranges between 0.3 and 0.7% according to the DSM-5 (DSM-IV-TR placed it at 1%), the prevalence of schizoaffective disorder is lower, at 0.3% according to DSM-5..

6. Affective symptoms

The sixth difference between schizoaffective disorder and schizophrenia has to do with affective symptoms (anhedonia, sadness, mania...).

On the one hand, affective (mood) symptoms are of great importance in schizoaffective disorder; so much so, that their presence is essential for a diagnosis of schizoaffective disorder. As we have seen, there must be, at some point, a manic episode or a major depressive episode.

On the other hand, in the case of schizophrenia, affective symptoms are not essential to make the diagnosis, although they often appear in the form of a manic episode or a major depressive episode.However, they often appear in the form of negative symptoms such as: abulia, restricted emotional expression, flat affect, depressive symptoms, etc. In addition, neither major depressive nor manic episodes usually occur in schizophrenia.

7. Onset

The onset of the disorder is another difference between schizoaffective disorder and schizophrenia, in schizoaffective disorder, the onset is usually acute, and in schizophrenia, insidious..

8. Other differences between schizoaffective disorder and schizophrenia

Other differences between schizoaffective disorder and schizophrenia refer to the frequency (or presence/absence) of certain symptoms, for example: auditory hallucinations, although they can occur in both disorders, appear more frequently in schizophrenia than in schizoaffective disorder; disorganized thinking is also more frequent in schizophrenia, as well as affective flattening. On the other hand, language poverty is also more marked in schizophrenia than in schizoaffective disorder..

Finally, the symptom of confusion is more prevalent in schizoaffective disorder than in schizophrenia, where it does not usually appear.

Bibliographical references:

• American Psychiatric Association -APA- (2002). Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR. Barcelona: Masson.
• American Psychiatric Association -APA- (2014). DSM-5. Diagnostic and statistical manual of mental disorders. Madrid: Panamericana.
• Belloch, A., Sandín, B. and Ramos, F. (2010). Manual de Psicopatología. Volume I and II. Madrid: McGraw-Hill.
• Lermanda, V., Holmgren, D., Soto-Aguilar, F. and Sapag, F. (2013). Schizoaffective disorder: How much schizophrenia, how much bipolar? Chilean journal of neuropsychiatry, 51(1): 46-60.
• WHO (2000). ICD-10. International classification of diseases, tenth edition. Madrid. Panamericana.