Early-onset schizophrenia (EOS; onset prior to age 18 years) is a serious, often debilitating disorder characterized by deficits in affect, cognition, and the ability to relate socially with others. EOS is often associated with significant morbidity, chronicity, and psychosocial impairment. Although schizophrenia and other severe psychotic disorders are rarely found in children, the profoundly negative effects of these illnesses and the necessity for intensive intervention require that clinicians who work with juveniles be familiar with their phenomenology, course of illness, assessment, and treatment. This chapter will review current research findings on the etiology, illness course, diagnostic considerations, and treatment of schizophrenia and related psychotic disorders in children and adolescents.

Until relatively recently, physicians were reluctant to diagnose schizophrenia and other psychotic disorders in children and adolescents. Indeed, the existence of an early onset form of schizophrenia has been debated since Kraepelin’s 1919 groundbreaking descriptive work on psychotic disorders. Although Kraepelin’s early descriptions of childhood-onset schizophrenia (COS) were similar to the adult form of the disorder, other descriptive psychopathologists lumped early-onset psychosis into a broader range of childhood syndromes that were defined by developmental deficits in language, social relations, perception, and movement. Psychotic speech and thought were believed to be important components of early-onset psychosis, but hallucinations and delusions were not required for a diagnosis. As a result, childhood psychoses often included a broader rubric of neurodevelopmental disorders, including autism.

It wasn’t until the 1970s that EOS was demonstrated to be distinct from other developmental disorders found in children such as autism and pervasive developmental disorders (PDD). In 1980, the American Psychiatric Association revised the criteria in the DSM-III (Diagnostic and Statistical Manual of Mental Disorders, Third Edition) so that EOS was diagnosed using the same criteria as those used for adult-onset schizophrenia. This practice has been maintained in subsequent DSM iterations, and is widely accepted as valid. Since a large portion of past research used the term COS overinclusively to describe a broader range of severely disturbed children, older studies of EOS need to be interpreted with caution.

Although EOS is a syndrome consisting of a group of varied symptoms including social withdrawal, self-care deficiencies, and bizarre behaviors, hallucinations and delusions are the characteristic symptoms of schizophrenia. Schizophrenia is usually categorized as having two
broad sets of clusters, positive and negative. Positive symptoms are those that are traditionally considered to be the disorder’s hallmark–florid hallucinations, delusions, and thought disorder. Negative symptoms include flat affect, anergia, and paucity of speech and thought. A third cluster, including disorganized speech, bizarre behavior, and poor attention, has been more recently discussed in the literature. A recent study of youth with early-onset psychotic disorders (including schizophrenia and bipolar disorder) found four symptom domains–positive symptoms, negative symptoms, behavioral problems, and dysphoria. Only negative symptoms were specifically associated with a diagnosis of schizophrenia. In descriptive studies, hallucinations, thought disorder, and flattened affect have been consistently found in EOS, whereas systematic delusions and catatonic symptoms are less frequent. Children with EOS exhibit low rates of incoherence and poverty of speech. When assessing a child’s thinking, it is important to distinguish between psychotic thought processes and developmental delays or language disorders.

Because EOS is relatively uncommon, few studies have examined incidence rates in the population. Available evidence suggests that the prevalence of schizophrenia in children is significantly lower than in adults, which is estimated to be approximately 1%. The onset rate rises dramatically during the age range of 15 to 30 years. Although the timing of disorder suggests a relationship with pubertal status, puberty has not been specifically associated with this trajectory.

In children less than 15 years of age, the prevalence rate has been estimated at 14 per 100,000. COS (very early onset–prior to age 13) is extremely rare with a prevalence of approximately 1.6 per 100,000. A Danish research study reported that only 1% of hospitalized schizophrenic youth were younger than 13 years of age and only 9% were younger than 15 years of age. COS occurs predominantly in males with ratios of approximately 2:1, but this ratio becomes closer to 1:1 as age increases. The youngest age of onset reported in the research literature is 3 years, although any case below age 8 years needs to be carefully scrutinized.

EOS is a heterogeneous disorder with multiple potential causes. A neurodevelopmental model suggests that environmental and genetic risk factors interact to disrupt key neurobiologic pathways, ultimately resulting in the disorder.

Although often characterized as a chronic condition, schizophrenia is a phasic illness, with the course and duration of the phases varying dependent on the illness and treatment response. The phases include (1) prodrome, (2) acute, (3) recuperative/recovery, and (4) residual. The prodromal phase involves general deterioration in functioning before the onset of psychotic symptoms in the active phase. Social withdrawal, idiosyncratic or bizarre preoccupations, unusual behaviors, academic decline, deteriorating self-care, increasing anxiety, depression, somatic complaints, and/or changes in appetite and sleep are common disturbances that occur
during the prodromal phase. Children in the prodromal phase of illness may also exhibit increased behavioral problems, including aggression, deceitfulness, and/or substance abuse. Such symptoms may represent a significant change from baseline functioning or a worsening of premorbid personality characteristics, which may make it difficult to identify the onset of the disorder in some children. Prodromes can vary from an acute change (days to weeks) to a more insidious, chronic impairment. Children tend to have more insidious onsets, whereas both acute (less than 1 year) and insidious onsets have been noted in adolescents.

The acute phase is marked by a predominance of positive psychotic symptoms (i.e., hallucinations, delusions, and disorganized thinking and behavior) that often shift to negative symptoms (i.e., affective flattening, avolition, and paucity of thought or speech) over time. This phase usually lasts between 1 and 6 months; however, it may last longer if the child does not respond adequately to treatment. As the acute psychosis remits, there is often a recuperative/recovery phase lasting several months where the patient continues to experience a significant degree of impairment. This is most often due to negative symptoms (flat affect, anergia, or social withdrawal), although it is common for some positive symptoms to persist. In addition, some patients will develop a postpsychotic depression characterized by dysphoria and flat affect.

The residual phase is characterized by the overall improvement of active psychotic symptoms. Generally, there is some persistence of negative symptoms, including social isolation, poverty of speech, odd beliefs/perceptions, and/or anergia. Individuals may continue to display peculiar behavior (e.g., poor hygiene and blunted or inappropriate affect) and disordered thinking (tangentiality and circumferentiality). The residual phase may last for several months or more. Some patients exhibit significant symptoms that do not respond to adequate pharmacologic and psychosocial treatment. These chronically ill patients exhibit the most severe impairment over time and require the most comprehensive treatment resources (e.g., medications combined with individual, family, and school interventions).

Several other psychiatric disorders manifest themselves with the expression of symptoms that either overlap or are easily mistaken for the primary symptoms of schizophrenia. These disorders are summarized in Table 15-1. If the symptoms of schizophrenia have not persisted for a 6-month
period, a diagnosis of schizophreniform disorder should be made. In juveniles, this often ultimately develops into schizophrenia. Schizoaffective disorder and mood disorders with psychotic features need to be ruled out when diagnosing a child or an adolescent presenting with psychotic symptoms. This is especially important for adolescents with bipolar disorder, because manic episodes during adolescence often include psychotic symptoms during the acute phase of illness. In fact, research suggests that early-onset bipolar disorder is associated with higher rates of psychosis than bipolar disorder of adult onset. As a result, bipolar youths are often misdiagnosed as schizophrenic when seen during an acute manic or mixed episode.

Psychotic symptoms during the acute phase of illness in EOS and early-onset bipolar disorder have considerable overlap. However, bipolar youths tend to have more mood congruent delusions and a lower percentage of hallucinations, loosening of associations, and negative symptoms than schizophrenic children. In addition to differences during the acute phase of illness, a thorough understanding of the child’s symptomatic and psychosocial history will aid in the differential diagnosis of schizophrenia and bipolar disorder. Youths with schizophrenia tend to have higher rates of premorbid social withdrawal and global impairments than bipolar youths. Further, psychotic symptoms must present only during active periods of depression or mania for a diagnosis of bipolar disorder. During euthymic periods, the bipolar patient will not experience psychotic symptoms.

Schizoaffective disorder and major depression with psychotic features may be the most difficult disorders to distinguish from schizophrenia. Negative symptoms of EOS are sometimes mistaken for depression, especially since dysphoria is commonly experienced as a part of the illness. Although an accurate picture of the temporal overlap between mood episodes and psychotic symptoms can be extremely difficult to obtain, this retrospective understanding is necessary to distinguish EOS from other psychotic disorders. For a diagnosis of depression with psychotic features, psychosis will be present only in the context of a severe major depressive episode. For a diagnosis of schizoaffective disorder, positive and negative psychotic symptoms must occur in the absence of significant mood episodes. The diagnosis of schizoaffective disorder appears to be somewhat unreliable in community settings. This is due in part to the tendency to use this diagnosis when mood and psychotic episodes co-occur (which may represent a primary mood disorder) or when an individual with schizophrenia has mood symptoms (i.e., dysphoria and grandiosity) without meeting the prerequisite mood episode criteria. Moreover, it is not uncommon in clinical settings that youth with emotional and behavioral dysregulation problems, often with traumatic histories, report psychotic-like symptoms and are diagnosed with schizoaffective disorder even though they may not actually have true psychosis.

Youths with traumatic histories, including physical, sexual, and/or emotional abuse, may report symptoms suggestive of auditory or visual hallucinations and/or paranoid delusions. However, these symptoms are generally either brief or atypical in nature, and the child does not demonstrate the other hallmark symptoms of schizophrenia. Further, some children with abuse histories may report psychotic symptoms in the context of reinforcement that occurs in a chaotic environment. Therefore, potential environmental reinforcers of psychotic behaviors should be assessed. For example, a child who reports hearing voices telling her to kill herself only when her parents are arguing (which, as a result, stops the parents from arguing because they are concerned with her behavior) is unlikely to have a primary psychotic condition such as EOS. Conversely, children with schizophrenia also may have suffered abuse; therefore, the mere presence of a trauma history does not rule out a primary psychotic illness.

Some psychoses are caused by substance intoxication or delirium. Patients with substanceinduced psychosis generally present with an acute onset of psychotic symptoms that are temporally related to the intake of the drug. Psychostimulants can produce paranoid delusions and disorientation, whereas hallucinogens may produce vivid hallucinations and delusions.
Substance intoxication and/or withdrawal can also induce delirium, which is associated with fluctuating mental status, varied levels of consciousness, and altered short-term memory. Therefore, it is important to identify if the psychosis is attributable to delirium or substances, because psychoses of these etiologies often have a different clinical course from psychosis due to EOS. Some youth may present with a psychotic illness in the context of substance/alcohol abuse, leading to an uncertain diagnosis. Because substance-induced psychosis generally clears within hours to days, psychotic symptoms that persist after a significant period of detoxification indicate the possibility of an underlying primary psychotic illness that may have been precipitated or exacerbated by substance abuse.