Text Size :

Course and Prevalence of Brief Psychotic Disorders

Despite the different diagnostic criteria and definitions, studies investigating brief psychotic disorders have found many common features among them.

Prevalence of Brief Psychotic Disorders

These disorders tend to be quite rare conditions. Studies on Brief Psychotic Disorder, Acute and Transient Psychotic Disorders (ATPD), and Nonaffective Acute Remitting Psychosis (NARP) have revealed that these disorders can be diagnosed in about 2.5-4% of all hospital-treated patients with Psychotic and Mood Disorders [ref, ref, ref].

These conditions tend not to start before adolescence, but thereafter can occur at any age [ref, ref, ref]. They also tend to occur much more commonly in women than in men, with studies showing that Brief Psychotic Disorder and ATPD are about 4 times more common in women [ref,ref], and that NARP occurs about twice as commonly in women as in men [ref, ref]. These findings are interesting given that Schizophrenia tends to be more common in men.

There has not been much published research on the prevalence rates of Schizophreniform Disorder.

Prognosis of Brief Psychotic Disorders

Brief Psychotic Disorder, ATPD, and NARP all tend to be recurring conditions, with episodes occurring on average once every 3 or 4 years [ref, ref, ref]. Yet, compared to Schizophrenia, their prognosis tends to be quite good, as individuals with these conditions often recover fully from their episodes and, on average, tend to maintain better levels of functioning in their life roles [ref, ref, ref].

Still, these diagnostic categories tend to be unstable in the sense that, for many people with these conditions, it becomes clear with time that their illnesses can be better described as Schizophrenia or Mood Disorders.

Prognosis of Brief Psychotic Disorder

In a study of adolescents followed for up to 4 years after a diagnosis of Brief Psychotic Disorder, 25% went on to be diagnosed with Schizophrenia or Schizoaffective Disorder, 15% were eventually diagnosed with Bipolar Disorder, and 40% had lingering psychotic symptoms; about 20% recovered fully [ref]. In that study, having a concurrent Anxiety Disorder predicted that an individual would go on to develop Bipolar Disorder.

That study also showed that adolescents with Brief Psychotic Disorder represent a group with a heavy burden of mental illness. Among these individuals, about 40% had Personality Disorders, close to 40% had Anxiety Disorders, 35% had a Disruptive Behavior Disorder, and 30% had ADHD [ref].

Prognosis of ATPD

Another study showed that half of the cases of ATPD change diagnosis after a 1 year period, most often to Schizophrenia (15%) or a Mood Disorder (25%) [ref]. About 35% of patients with ATPD engage in suicidal behaviors [ref].

Prognosis of Schizophreniform Disorder

The majority of individuals with Schizophreniform Disorder are eventually diagnosed with Schizophrenia or a Mood Disorder [ref]. One recent, long-term follow-up study found that close to half of these individuals are eventually diagnosed with Schizophrenia, over a third with a Mood Disorder, and about 20% end up having other psychotic disorders like Delusional Disorder and Schizoaffective Disorder [ref]. Only a very small minority are eventually found to be free of mental illness [ref].

Despite the fact that the DSM-IV-TR describes a form of Schizophreniform Disorder with Good Prognostic Factors, not all studies agree on whether these factors truly indicate a more favorable course of the illness [ref, ref]. Other good prognostic factors have also been proposed, such as having a family history of Mood Disorders [ref].

Prognosis of NARP

On the other hand, people diagnosed with NARP actually have very low rates of being diagnosed with Schizophrenia later on. One study showed that after a 2 year follow-up period only 6% of people with NARP developed Schizophrenia and another 6% were diagnosed with Delusional Disorder, as opposed to people with other forms of brief psychosis, where close to 70% were diagnosed with Schizophrenia [ref]. The rates of people with NARP eventually being diagnosed with a Mood Disorder have not been reported.

Commonalities Among the Different Brief Psychotic Disorders

More research is required to determine the best way to describe and diagnose brief psychotic disorders.

One study found that among patients with ATPD, about 60% could be diagnosed with Brief Psychotic Disorder, and another 30% could be diagnosed with Schizophreniform Disorder, but that both of these groups were virtually identical in many ways, including the gender distribution and favorable course and outcome [ref]. This suggests that the 1 month cut-off for Brief Psychotic Disorder may be artificial and not useful.

This idea would be supported by the research that has been done on NARP, which has showed that using a 6 month cut-off for the duration of an episode can still distinguish these individuals from those who will go on to develop Schizophrenia, so long as one uses the condition that the psychotic symptoms should begin rapidly within a 2 week period [ref].

Overall, current evidence suggests that NARP may be the best way to capture those individuals with brief psychotic symptoms who are not likely to progress to Schizophrenia.


prev | next