Psychosis as a common thread across psychiatric disorders

Ask a psychiatrist to name a psychotic disorder, and the answer will most likely be “schizophrenia.” But if you closely examine the symptom structure of DSM-5 psychiatric disorders, you will note the presence of psychosis in almost all of them.

Fixed false beliefs and impaired reality testing are core features of psychosis. Those are certainly prominent in severe psychoses such as schizophrenia, schizoaffective disorder, or delusional disorder. But psychosis is actually a continuum of varying severity across most psychiatric disorders, although they carry different diagnostic labels. Irrational false beliefs and impaired functioning due to poor reality testing are embedded among many DSM-5 disorders. Hallucinations are less common; they are perceptual aberrations, not thought abnormalities, although they can trigger delusional explanations as to their causation.

Consider the following:

• Bipolar disorder. A large proportion of patients with bipolar disorder manifest delusions, usually grandiose, but often paranoid or referential.
• Major depressive disorder (MDD). Although regarded as a “pure mood disorder,” the core symptoms of MDD—self-deprecation and sense of worthlessness—as well as the poor reality testing of suicidal thoughts (that death is a better option than living) are psychotic false beliefs.
• Anxiety and panic disorder. The central symptom in anxiety and panic attacks is a belief in impending doom and/or death. The fear in anxiety disorders is actually based on a false belief (eg, if I get on the plane, it will crash, and I will die). Thus, technically an irrational/psychotic thought process underpins the terror and fear of anxiety disorders.
• Borderline personality disorder. Frank psychotic symptoms, such as paranoid beliefs, are known to be a component of borderline personality disorder symptoms. Although these symptoms tend to be brief and episodic, they can have a deleterious effect on the person’s coping and relationships.
• Other personality disorders. While many individuals with narcissistic personality disorder are functional, their exaggerated sense of self-importance, entitlement, and self-aggrandizement certainly qualifies as a fixed false belief. Patients with other personality disorders, such as schizotypal and paranoid, are known to harbor false beliefs or magical thinking.
• Body dysmorphic disorder. False beliefs about one’s appearance (such as blemishes or asymmetry) are at the center of this disorder, and it meets the litmus test of a psychosis.
• Anorexia nervosa. This disorder is well known to be characterized by a fixed false belief that one is “fat,” even when the patient’s body borders on being cachectic in appearance according to objective observers.
• Autism. This spectrum of diseases includes false beliefs that drive the ritualistic or odd behaviors.
• Obsessive-compulsive disorder. Although obsessions are usually ego-dystonic, in severe cases, they become ego-syntonic, similar to delusions. On the other hand, compulsions are often driven by a false belief, such as believing that one’s hands are dirty and must be washed incessantly, or that the locks on the door must be rechecked repeatedly because an intruder may break into the house and harm the inhabitants.
• Neurodegenerative syndromes. Neurodegenerative syndromes are neuropsychiatric disorders that very frequently include psychotic symptoms, such as paranoid delusions, delusions of marital infidelity, Capgras syndrome, or folie à deux. These disorders include Alzheimer’s disease, Parkinson’s disease, Lewy body dementia, frontal temporal dementia, metachromatic leukodystrophy, Huntington’s chorea, temporal lobe epilepsy, stroke, xenomelia, reduplicative phenomena, etc. This reflects the common emergence of faulty thinking with disintegration of neural tissue, both gray and white matter.

Continue to: So it should not be...

So it should not be surprising that antipsychotic medications, especially second-generation agents, have been shown to be helpful as monotherapy or adjunctive therapy in practically all the above psychiatric disorders, whether on-label or off-label.

Finally, it should also be noted that a case has been made for the existence of one dimension in all mental disorders manifesting in multiple psychopathologies.¹ It is possible that a continuum of delusional thinking is a common thread across many psychiatric disorders due to this putative shared dimension. The milder form of this dimension may also explain the presence of pre-psychotic thinking in a significant proportion of the general population who do not seek psychiatric help.² Just think of how many people you befriend, socialize with, and regard as perfectly “normal” endorse wild superstitions and astrological predictions, or believe in various conspiracy theories that have no basis in reality.

To comment on this editorial or other topics of interest: henry.nasrallah@currentpsychiatry.com.

Ask a psychiatrist to name a psychotic disorder, and the answer will most likely be “schizophrenia.” But if you closely examine the symptom structure of DSM-5 psychiatric disorders, you will note the presence of psychosis in almost all of them.

Fixed false beliefs and impaired reality testing are core features of psychosis. Those are certainly prominent in severe psychoses such as schizophrenia, schizoaffective disorder, or delusional disorder. But psychosis is actually a continuum of varying severity across most psychiatric disorders, although they carry different diagnostic labels. Irrational false beliefs and impaired functioning due to poor reality testing are embedded among many DSM-5 disorders. Hallucinations are less common; they are perceptual aberrations, not thought abnormalities, although they can trigger delusional explanations as to their causation.

Consider the following:

• Bipolar disorder. A large proportion of patients with bipolar disorder manifest delusions, usually grandiose, but often paranoid or referential.
• Major depressive disorder (MDD). Although regarded as a “pure mood disorder,” the core symptoms of MDD—self-deprecation and sense of worthlessness—as well as the poor reality testing of suicidal thoughts (that death is a better option than living) are psychotic false beliefs.
• Anxiety and panic disorder. The central symptom in anxiety and panic attacks is a belief in impending doom and/or death. The fear in anxiety disorders is actually based on a false belief (eg, if I get on the plane, it will crash, and I will die). Thus, technically an irrational/psychotic thought process underpins the terror and fear of anxiety disorders.
• Borderline personality disorder. Frank psychotic symptoms, such as paranoid beliefs, are known to be a component of borderline personality disorder symptoms. Although these symptoms tend to be brief and episodic, they can have a deleterious effect on the person’s coping and relationships.
• Other personality disorders. While many individuals with narcissistic personality disorder are functional, their exaggerated sense of self-importance, entitlement, and self-aggrandizement certainly qualifies as a fixed false belief. Patients with other personality disorders, such as schizotypal and paranoid, are known to harbor false beliefs or magical thinking.
• Body dysmorphic disorder. False beliefs about one’s appearance (such as blemishes or asymmetry) are at the center of this disorder, and it meets the litmus test of a psychosis.
• Anorexia nervosa. This disorder is well known to be characterized by a fixed false belief that one is “fat,” even when the patient’s body borders on being cachectic in appearance according to objective observers.
• Autism. This spectrum of diseases includes false beliefs that drive the ritualistic or odd behaviors.
• Obsessive-compulsive disorder. Although obsessions are usually ego-dystonic, in severe cases, they become ego-syntonic, similar to delusions. On the other hand, compulsions are often driven by a false belief, such as believing that one’s hands are dirty and must be washed incessantly, or that the locks on the door must be rechecked repeatedly because an intruder may break into the house and harm the inhabitants.
• Neurodegenerative syndromes. Neurodegenerative syndromes are neuropsychiatric disorders that very frequently include psychotic symptoms, such as paranoid delusions, delusions of marital infidelity, Capgras syndrome, or folie à deux. These disorders include Alzheimer’s disease, Parkinson’s disease, Lewy body dementia, frontal temporal dementia, metachromatic leukodystrophy, Huntington’s chorea, temporal lobe epilepsy, stroke, xenomelia, reduplicative phenomena, etc. This reflects the common emergence of faulty thinking with disintegration of neural tissue, both gray and white matter.

Continue to: So it should not be...

So it should not be surprising that antipsychotic medications, especially second-generation agents, have been shown to be helpful as monotherapy or adjunctive therapy in practically all the above psychiatric disorders, whether on-label or off-label.

Finally, it should also be noted that a case has been made for the existence of one dimension in all mental disorders manifesting in multiple psychopathologies.¹ It is possible that a continuum of delusional thinking is a common thread across many psychiatric disorders due to this putative shared dimension. The milder form of this dimension may also explain the presence of pre-psychotic thinking in a significant proportion of the general population who do not seek psychiatric help.² Just think of how many people you befriend, socialize with, and regard as perfectly “normal” endorse wild superstitions and astrological predictions, or believe in various conspiracy theories that have no basis in reality.

To comment on this editorial or other topics of interest: henry.nasrallah@currentpsychiatry.com.

Ask a psychiatrist to name a psychotic disorder, and the answer will most likely be “schizophrenia.” But if you closely examine the symptom structure of DSM-5 psychiatric disorders, you will note the presence of psychosis in almost all of them.

Fixed false beliefs and impaired reality testing are core features of psychosis. Those are certainly prominent in severe psychoses such as schizophrenia, schizoaffective disorder, or delusional disorder. But psychosis is actually a continuum of varying severity across most psychiatric disorders, although they carry different diagnostic labels. Irrational false beliefs and impaired functioning due to poor reality testing are embedded among many DSM-5 disorders. Hallucinations are less common; they are perceptual aberrations, not thought abnormalities, although they can trigger delusional explanations as to their causation.

Consider the following:

• Bipolar disorder. A large proportion of patients with bipolar disorder manifest delusions, usually grandiose, but often paranoid or referential.
• Major depressive disorder (MDD). Although regarded as a “pure mood disorder,” the core symptoms of MDD—self-deprecation and sense of worthlessness—as well as the poor reality testing of suicidal thoughts (that death is a better option than living) are psychotic false beliefs.
• Anxiety and panic disorder. The central symptom in anxiety and panic attacks is a belief in impending doom and/or death. The fear in anxiety disorders is actually based on a false belief (eg, if I get on the plane, it will crash, and I will die). Thus, technically an irrational/psychotic thought process underpins the terror and fear of anxiety disorders.
• Borderline personality disorder. Frank psychotic symptoms, such as paranoid beliefs, are known to be a component of borderline personality disorder symptoms. Although these symptoms tend to be brief and episodic, they can have a deleterious effect on the person’s coping and relationships.
• Other personality disorders. While many individuals with narcissistic personality disorder are functional, their exaggerated sense of self-importance, entitlement, and self-aggrandizement certainly qualifies as a fixed false belief. Patients with other personality disorders, such as schizotypal and paranoid, are known to harbor false beliefs or magical thinking.
• Body dysmorphic disorder. False beliefs about one’s appearance (such as blemishes or asymmetry) are at the center of this disorder, and it meets the litmus test of a psychosis.
• Anorexia nervosa. This disorder is well known to be characterized by a fixed false belief that one is “fat,” even when the patient’s body borders on being cachectic in appearance according to objective observers.
• Autism. This spectrum of diseases includes false beliefs that drive the ritualistic or odd behaviors.
• Obsessive-compulsive disorder. Although obsessions are usually ego-dystonic, in severe cases, they become ego-syntonic, similar to delusions. On the other hand, compulsions are often driven by a false belief, such as believing that one’s hands are dirty and must be washed incessantly, or that the locks on the door must be rechecked repeatedly because an intruder may break into the house and harm the inhabitants.
• Neurodegenerative syndromes. Neurodegenerative syndromes are neuropsychiatric disorders that very frequently include psychotic symptoms, such as paranoid delusions, delusions of marital infidelity, Capgras syndrome, or folie à deux. These disorders include Alzheimer’s disease, Parkinson’s disease, Lewy body dementia, frontal temporal dementia, metachromatic leukodystrophy, Huntington’s chorea, temporal lobe epilepsy, stroke, xenomelia, reduplicative phenomena, etc. This reflects the common emergence of faulty thinking with disintegration of neural tissue, both gray and white matter.

Continue to: So it should not be...

So it should not be surprising that antipsychotic medications, especially second-generation agents, have been shown to be helpful as monotherapy or adjunctive therapy in practically all the above psychiatric disorders, whether on-label or off-label.

Finally, it should also be noted that a case has been made for the existence of one dimension in all mental disorders manifesting in multiple psychopathologies.¹ It is possible that a continuum of delusional thinking is a common thread across many psychiatric disorders due to this putative shared dimension. The milder form of this dimension may also explain the presence of pre-psychotic thinking in a significant proportion of the general population who do not seek psychiatric help.² Just think of how many people you befriend, socialize with, and regard as perfectly “normal” endorse wild superstitions and astrological predictions, or believe in various conspiracy theories that have no basis in reality.

To comment on this editorial or other topics of interest: henry.nasrallah@currentpsychiatry.com.