Adolescents who present with symptoms that suggest a psychotic disorder pose a number of diagnostic and treatment challenges. This article attempts to provide a practical guide to the assessment and management of adolescents with severe psychotic illness, including schizophrenia, schizophrenia-like disorders, and bipolar disorder. Epidemiology, differential diagnosis, causes, and predisposing factors will also be covered in the context of a comprehensive framework for assessment and management.
Prevalence of psychosis in adolescence
Five percent of adults with schizophrenia report onset of psychosis before age 15 years.1 Despite the lack of precise incidence and prevalence rates from childhood or adolescent population–based studies, it is generally agreed that the prevalence of psychotic disorders increases markedly during adolescence.
Gillberg and colleagues2 estimate the prevalence of psychosis in 13- to 19-year-olds as 0.54%, increasing from 0.9 per 10,000 at age 13 years to 17.6 per 10,000 at age 18 years.2 Male preponderance has been reported in some studies, but this is not a consistent finding and may be related to lack of robust data.
Adult bipolar disorder prevalence is estimated at 1%. However, community studies in adolescents have indicated a prevalence of 0.5% to 1%, which varies with age and diagnostic criteria. Complete ascertainment of cases in this age group remains a concern: many episodes are only recognized in retrospect.3-6
The diagnosis of schizophrenia—early-onset psychosis in adolescents younger than 18 years—is based on the same DSM-IV criteria as for adults. The diagnostic criteria focus on 3 characteristic symptoms7:
• Reality distortion (hallucinations and delusions).
• Psychomotor poverty (for example, poverty of speech, poor motivation, social withdrawal, and a flat affect).
Diagnostic criteria and atypical presentations
DSM-IV diagnosis of schizophrenia requires a 6-month period of disturbance that can include both a prodromal period of deterioration before the onset of psychotic symptoms and a residual phase. However, active psychotic symptoms must be present for at least 1 month. One important modification of criteria from those used in adults is that a failure to achieve age-appropriate interpersonal, academic, or occupational progress can substitute for significant deterioration in self-care and social, educational, or occupational functioning below premorbid levels.
In episodes lasting between 1 and 6 months, a diagnosis of schizophreniform disorder may be made. Briefer episodes that have a sudden onset and that resolve rapidly to the premorbid level of functioning within a month without evidence of an organic cause are diagnosed as brief psychotic disorders, according to DSM-IV criteria. Because classical schizophrenia may eventually develop in some patients with this diagnosis, ongoing follow-up is required. The presence of a clear stressor is sometimes associated with a brief reactive psychosis, although, without further follow-up, this presumption cannot be used to make a definitive diagnosis.8
Affective disorder in adolescents (whether manic, depressive, or mixed) can present with psychotic symptoms such as delusions, hallucinations, or thought disorder. It may be relatively easy to distinguish affective disorder from schizophrenia when the patient has symptoms that are mood-congruent with affective episodes and no clear negative symptoms. A firm diagnosis of affective disorder may be more difficult to establish in adolescents who present with bizarre and persecutory delusions, mood incongruent hallucinations with lability of mood, or significant functional deterioration. The diagnostic uncertainty in such cases may have to be accepted and shared with parents and/or caregivers while awaiting a clarification as the clinical picture evolves. Pointers to possible schizophrenia might be the insidious onset of affective symptoms with difficulties in premorbid adjustment and functioning, a family history of schizophrenia, and the presence of a significant thought disorder.9
Concurrent presentation of schizophrenic and affective symptoms that meet criteria for schizoaffective disorder appears to carry a short-term clinical course and a longer-term prognosis intermediate between schizophre-nia and affective disorder.
Acute psychotic, manic, or hypomanic symptoms may also present in association with substance misuse or with organic conditions that need to be distinguished by a careful history, physical examination, and appropriate investigations. A period of enforced abstinence may be necessary to determine whether symptoms are truly enduring.
Induced delusional disorder (folie deux) may be encountered in adolescents in a close or enmeshed emotional relationship with a psychotic parent or caregiver or sibling. In this setting, psychotic beliefs may be shared rather than actually experienced by the adolescent.10
The prodromal phase
Adolescents occasionally present with nonspecific psychotic symptoms, such as odd beliefs, mistrust of others, and magical thinking. These overvalued ideas lead to a decline in interpersonal and school functioning. Whether this represents the prodromal phase of a severe psychotic disorder is difficult to answer prospectively. However, frank psychosis develops in up to 40% of affected patients within 12 months of symptom onset.11 A positive family history of psychosis and marked impairment of functioning with evolving psychosis-like symptoms are considered to be risk factors for psychotic illness. Adolescent schizophrenia, in particular, is associated with motor or language developmental delays and premorbid cognitive and social impairments that seem to merge with the onset of an insidious psychotic illness.12
While research in psychological and pharmacological interventions is ongoing, specific clinical management is limited to continued monitoring to identify those who may be at risk for a psychotic episode and to address specific presenting problems with practical and psychotherapeutic support.8,13 A high index of suspicion should be maintained for adolescents who manifest the risk factors mentioned above so that prompt treatment can be initiated at the onset of a clear psychotic episode.
Notwithstanding the ongoing debate about the role of active pharmacological and psychological treatment of prodromal symptoms of schizophrenia, any treatment option at this stage requires an explanation to the patient and his or her parent or caregiver. This should include information about the incomplete evidence base and a detailed discussion of the relative risks and benefits. The goal is to actively involve the patient and his family in making treatment decisions.11 A conservative approach to treatment at this stage is advised. Psychosocial and other benign options should be employed before antipsychotics.14