Schizoaffective disorder is a mental disorder where symptoms of both schizophrenia (psychosis) and a mood disorder, either bipolar disorder or depression, co-occur. The main diagnostic criterion is the presence of psychotic symptoms for at least two weeks without prominent mood symptoms. Common symptoms include hallucinations, delusions, disorganized speech and thinking, as well as mood episodes. Schizoaffective disorder can often be misdiagnosed when the correct diagnosis may be psychotic depression, bipolar I disorder, schizophreniform disorder, or schizophrenia. This is a problem as treatment and prognosis differ greatly for most of these diagnoses. Many people with schizoaffective disorder have other mental disorders, including anxiety disorders.
There are three forms of schizoaffective disorder: bipolar or manic type (marked by symptoms of schizophrenia and mania), depressive type (marked by symptoms of schizophrenia and depression), and mixed type (marked by symptoms of schizophrenia, depression, and mania). Auditory hallucinations are the most common type. The onset of symptoms usually begins in adolescence or young adulthood.
Genetics (researched in the field of genomics); problems with neural circuits; chronic early and chronic or short-term current environmental stress appear to be important causal factors. No single organic cause has been isolated, but extensive evidence exists for abnormalities in the metabolism of tetrahydrobiopterin (BH4), dopamine, and glutamic acid in people with schizophrenia, psychotic mood disorders, and schizoaffective disorder.
While a diagnosis of schizoaffective disorder is rare (0.3% of the general american population), it is considered a common diagnosis among psychiatric disorders. Diagnosis of schizoaffective disorder is based on DSM-5 criteria, which consist principally of the presence of symptoms of schizophrenia, mania, and depression, and the temporal relationships between them.
The main current treatment is antipsychotic medication combined with either mood stabilizers or antidepressants (or both). There is growing concern by some researchers that antidepressants may increase psychosis, mania, and long-term mood episode cycling in the disorder. When there is risk to self or others, usually early in treatment, psychiatric hospitalization may be necessary. Psychiatric rehabilitation, psychotherapy, and vocational rehabilitation are very important for recovery of higher psychosocial function. As a group, people diagnosed with schizoaffective disorder using DSM-IV and ICD-10 criteria (now ICD-11) have a better prognosis, but they have variable individual psychosocial functional outcomes compared to people with mood disorders (from worse to the same). Outcomes for people with DSM-5-diagnosed schizoaffective disorder depend on data from prospective cohort studies, which have not been completed. The DSM-5 updated the diagnostic criteria from the DSM-IV because the latter led to overdiagnosis. (That is, DSM-IV criteria led to many patients being misdiagnosed with the disorder.) DSM-IV prevalence estimates were less than one percent of the population (in the range of 0.5–0.8%); newer DSM-5 prevalence estimates are not yet available.
Signs and symptoms Schizoaffective disorder is defined by mood disorder-free psychosis in the context of a long-term psychotic and mood disorder. Psychosis must meet criterionA for schizophrenia which may include delusions, hallucinations, disorganized speech and behavior and negative symptoms. Both delusions and hallucinations are classic symptoms of psychosis. Delusions are false beliefs which are strongly held despite evidence to the contrary. Beliefs should not be considered delusional if they are in keeping with cultural beliefs. Delusional beliefs may or may not reflect mood symptoms (for example, someone experiencing depression may or may not experience delusions of guilt). Hallucinations are disturbances in perception involving any of the five senses, although auditory hallucinations (or "hearing voices") are the most common. Negative symptoms include alogia (lack of speech), blunted affect (reduced intensity of outward emotional expression), avolition (lack of motivation), and anhedonia (inability to experience pleasure). Negative symptoms can be more lasting and more debilitating than positive symptoms of psychosis.
Mood symptoms include mania, hypomania, mixed episode, or depression, and tend to be episodic rather than continuous. A mixed episode represents a combination of symptoms of mania and depression at the same time. Symptoms of mania include elevated or irritable mood, grandiosity (inflated self-esteem), agitation, risk-taking behavior, decreased need for sleep, poor concentration, rapid speech, and racing thoughts. Symptoms of depression include low mood, apathy, changes in appetite or weight, disturbances in sleep, changes in motor activity, fatigue, guilt or feelings of worthlessness, and suicidal thinking.
DSM-5 states that if a patient only experiences psychotic symptoms during a mood episode, their diagnosis is mood disorder with psychotic features and not schizophrenia or schizoaffective disorder. If the patient experiences psychotic symptoms without mood symptoms for longer than a two-week period, their diagnosis is either schizophrenia or schizoaffective disorder. If mood disorder episodes are present for the majority and residual course of the illness and up until the diagnosis, the patient can be diagnosed with schizoaffective disorder.
Causes A combination of genetic and environmental factors is believed to play a role in the development of schizoaffective disorder.
Viewed broadly, then, biological and environmental factors interact with a person's genes in ways that may increase or decrease the risk for developing schizoaffective disorder; exactly how this happens (the biological mechanism) is not yet known. Schizophrenia spectrum disorders, of which schizoaffective disorder is a part, have been increasingly linked to advanced paternal age at the time of conception, a known cause of genetic mutations. The physiology of people diagnosed with schizoaffective disorder appears to be similar, but not identical, to that of those diagnosed with schizophrenia and bipolar disorder; however, human neurophysiological function in normal brain and mental disorder syndromes is not fully understood.
While there are various medications and treatment options for those with schizoaffective disorder, this disorder can affect a person for their entire lifespan. In some cases, this disorder can affect a person's ability to have a fulfilling social life, and they may also have trouble forming bonds or relationships with others. Schizoaffective disorder is also more likely to occur in women and begins at a young age.
Substance use disorder
A clear causal connection between substance use and psychotic spectrum disorders, including schizoaffective disorder, has been difficult to prove. In the specific case of cannabis (marijuana), however, evidence supports a link between earlier onset of psychotic illness and cannabis use. The more often cannabis is used, particularly in early adolescence, the more likely a person is to develop a psychotic illness, with frequent use being correlated with double the risk of psychosis and schizoaffective disorder. A 2009 Yale review stated that in individuals with an established psychotic disorder, cannabinoids can exacerbate symptoms, trigger relapse, and have negative consequences on the course of the illness. While cannabis use is accepted as a contributory cause of schizoaffective disorder by many, it remains controversial, since not all young people who use cannabis later develop psychosis, but those who do use cannabis have an increased odds ratio of about 3. Certain drugs can imitate symptoms of schizophrenia (which is known to have similar symptoms to schizoaffective disorder). This is important to note when including that substance-induced psychosis should be ruled out when diagnosing patients, so that patients are not misdiagnosed.
Mechanisms Though the pathophysiology of schizoaffective disorder remains unclear, studies suggest that dopamine, norepinephrine, and serotonin may be factors in the development of the disorder. White matter and grey matter reductions in the right lentiform nucleus, left superior temporal gyrus, and right precuneus, and other areas in the brain are also characteristic of schizoaffective disorder. Deformities in white matter have also been found to worsen with time in individuals with schizoaffective disorder. Due to its role in emotional regulation, researchers believe that the hippocampus is also involved in the progression of schizoaffective disorder. Specifically, psychotic disorders (such as schizoaffective disorder) have been associated with lower hippocampal volumes. Moreover, deformities in the medial and thalamic regions of the brain have been implicated as contributing factors to the disorder as well.
Diagnosis Psychosis as a symptom of a psychiatric disorder is first and foremost a diagnosis of exclusion. So, a new-onset episode of psychosis cannot be considered a symptom of a psychiatric disorder until other organic causes of psychosis are ruled out. Many clinicians improperly perform, or entirely miss, this step, introducing avoidable diagnostic error and misdiagnosis.
An initial assessment involves a thorough history-taking and physical examination. Although there are no objective laboratory tests available to diagnose schizoaffective disorder definitively, laboratory investigations should be conducted to rule out psychosis resulting from substance use, medications, toxins or poisons, surgical complications, or other organic conditions. Since non-medical mental health practitioners lack training to identify medical causes of psychosis, individuals experiencing such symptoms should be referred to an emergency department or hospital for further evaluation.
Delirium should be ruled out; it is characterized by visual hallucinations, an acute onset, and fluctuating levels of consciousness, suggesting other underlying factors, including medical illnesses. Excluding medical illnesses associated with psychosis is performed by using blood tests to measure:
Thyroid-stimulating hormone to exclude hypo- or hyperthyroidism, Basic electrolytes and serum calcium to rule out a metabolic disturbance, Complete blood count, including ESR to rule out a systemic infection or chronic disease, and Serology to exclude syphilis or HIV infection.
Other investigations that may be performed include:
EEG to exclude epilepsy, and an MRI or CT scan of the head to exclude brain lesions.
Blood tests are not usually repeated for relapse in people with an established diagnosis of schizoaffective disorder, unless there is a specific medical indication. These may include serum blood sugar, if olanzapine has previously been prescribed; thyroid function, if lithium has previously been taken to rule out hypothyroidism; liver function tests, if chlorpromazine has been prescribed; creatine kinase levels to exclude neuroleptic malignant syndrome; and a urinalysis and serum toxicology screening, if substance use is suspected. Assessment and treatment may be done on an outpatient basis; admission to an inpatient facility is considered if there is a risk to self or others.
Because psychosis may be precipitated or exacerbated by common classes of psychiatric medications, such as antidepressants, ADHD stimulant medications, and sleep medications, prescribed medication-induced psychosis should be ruled out, particularly for first-episode psychosis. This is an essential step to reduce diagnostic error and to evaluate potential medication sources of further patient harm. Regarding prescribed medication sources of patient harm, Yale School of Medicine