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Key points
- Recognizing the context of someone's psychotic symptoms is key to understanding what diagnosis the symptoms belong to.
- Differentiating schizophrenia-spectrum conditions is a matter of identifying symptom arrangement and duration.
- Psychosis that occurs only during a mood episode is not the same as Schizoaffective Disorder.
As I wrote in a previous post, there are six specific conditions within the Schizophrenia and Related Conditions (AKA psychotic disorders) chapter of the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5). Though this may seem like a lot to get a handle on, it’s really just a matter of understanding symptom arrangement and duration:
Schizophrenia-Spectrum Disorders
Schizophrenia. For at least six months, some combination of at least two psychotic disorder symptoms as outlined here.
The symptom combinations are very often hallucinations and/or delusions coupled with a collection of negative symptoms. It’s also not unusual for symptoms to be primarily disorganized in nature, with some hallucinatory activity. Some people experience items from each symptom category. If catatonia is to occur, it may creep in during the course of an episode like the above examples.
Additionally, in schizophrenia, there's usually a marked prodromal phase leading into more severe symptoms like chronic delusions, frequent hallucinations, and gross disorganization. ("Prodromal" is a fancy term for a prelude of more subtle symptoms before becoming floridly psychotic.) There also tends to be a tapering-off period known as the “residual phase” before an episode remits.
Schizophreniform. As above, but the active-phase symptoms last one month up to six months. While some people periodically experience just a few months of symptoms and stabilize, many with schizophreniform go on to develop schizophrenia.
Brief Psychotic Disorder. For one day to one month, the person experiences one or more of the following: hallucinations, delusions or disorganized thought process. There could well be some combination of them, also.
The episode also tends to come on fast, on the heels of a psychosocial stressor, and is therefore sometimes known as “reactive psychosis.” There is no prodromal phase, and people often quickly return to baseline functioning in the absence of a residual phase. It is important to note that this experience is not limited to the context of one of the conditions below that can harbor psychotic features.
Schizoaffective Disorder. This condition is most easily conceptualized as schizophrenia with a superimposed Major Depressive or Bipolar Disorder, and it tends to be chronic. Technically, the person must experience at least two weeks of psychotic symptoms and develop a full-duration mood episode; when the mood episode resolves, they are still psychotic at baseline for at least two more weeks. If it is only major depressive episodes that are superimposed, it is Schizoaffective Disorder, Major Depressive Type; should mania/hypomania/mixed episodes also occur, it's Schizoaffective Disorder, Bipolar Type.
Delusional Disorder. Simply, the presence of a delusion/delusions that persist for at least one month, in the absence of any history of schizophrenia. There is no other current condition like an affective disorder, personality disorder, or OCD-spectrum condition that it may be a part of.
Schizotypal Personality Disorder. For more on this disorder, please refer to my earlier post, "Schizophrenia or Schizotypal Personality?"
Conditions with psychotic features
Now that it’s clear how to tell the schizophrenia-spectrum conditions apart, let’s look at how to differentiate those from conditions that have psychotic features.
Affective Psychosis. This means the psychosis is associated with Major Depression or Bipolar Disorder. At first, this may be hard to tell from Schizoaffective Disorder. However, the noticeable difference is that the psychosis only occurs during a major depressive, manic, or mixed episode.
Borderline Personality Disorder. Here, the psychotic symptoms are very likely limited to hallucinations and delusions, and corollary to an interpersonal complication. To illustrate, the pathology of Borderline Personality Disorder (BPD) stems from fears of abandonment/rejection. Therefore, if someone with BPD is, say, in a romantic relationship and their partner asks for space because they're feeling smothered, the BPD patient reflexively perceives this as a guaranteed pending abandonment because they're unacceptable, and "surely they're cheating on me with someone else." So convinced are they that they are being cheated on, they begin spying on the partner. Meanwhile, they may be hearing voices that they're no good, because if they were, this person wouldn't have cheated on them.
Delusional specifier of OCD, Hoarding, and Body Dysmorphic Disorders. The patient has a delusional thought process related to one of these conditions that only occurs in the context of one of these disorders.
An example of this would be someone with OCD who has an intrusive thought or image enter their mind that the big bump they encountered while driving on the dark road might have been a pedestrian. Despite backing up and checking multiple times, they're not convinced they didn't hit someone. It's the nature of someone with severe OCD to then obsess, "What if the person ran off into the woods and died of internal bleeding?" They then begin scouring newspapers for missing persons in the area who may have disappeared the night of the "bump" and they fear driving in that vicinity in case someone recognizes their car. In effect, a paranoid delusion evolved from the obsession.
Dissociative Identity Disorder. People with DID often report hearing voices. However, it is not unusual for them to say they're hearing the voices of the other identities or something similar, that tips us off. They also are often prone to describe them as being in their head, rather sounding like someone is talking to them, but nobody is there, as in other psychotic experiences.
The DID example illustrates the importance of gathering as much detail about the context of a person's experience as possible. Referring this patient to a psychiatrist for antipsychotic medications will do little good. No medication can integrate or otherwise manage alternative identities; they require trauma therapy.
Paranoid Personality Disorder. In this condition, people are highly suspicious of the motives and intentions of others, and have always been this way. While the paranoid thoughts are usually more of a defensive misconstruing of data, they sometimes reach delusional proportions. (For more, see Paranoia in Mental Illness.)
PTSD. Some PTSD sufferers may relive their traumatic experience in the form of hallucinatory activity. Here, the hallucinations happen only in the context of the trauma. Very often this is of a somatic nature, such as feeling the bullet or stab wound occurring, or the hands of a perpetrator. Other times they may be more olfactory in nature, such as war veterans who report smelling diesel, jet fuel, or gunpowder associated with a traumatic event.
It must be kept in mind that clinicians should always rule out that an underlying medical condition or substance is causing the psychotic experience. This is especially true if the person has no personal or family history of the symptoms or no trauma history, or the symptoms arose abruptly or are highly unusual in nature (as discussed in this post about medical mimicry).
Lastly, the above conditions are not always mutually exclusive. It's quite possible that someone with BPD could also have Major Depressive Disorder with Psychotic Features, or someone could have schizophrenia and PTSD. It's essential to gather as much information as possible about the psychotic experiences for the most accurate understanding to make sure proper care is provided.
