Screening and treatment of adolescents with schizofrenia

Schizophrenia is a severe psychiatric disease characterized by changes in thinking, perception and behaviour that conflict with reality as experienced by other people. A period of social isolation, neglect of hygiene or blunted emotions sometimes precedes these delusions or hallucinations. Most patients suffer the first symptoms during adolescence. Schizophrenia or a related disorder occurs in approximately 0.5% of the population; combined with the disease's early onset and often chronic course, this leads to considerable economic and human costs.

Guidelines for treatment recently became available in the Netherlands. The antipsychotic drug treatment indicated in the guidelines generally results in an improvement, but the disease appears to be chronic in the majority of patients.

The cause of schizophrenia is unknown. Genetic as well as environmental factors appear to play an important role in the disease's occurrence. However, the actual genes involved in schizophrenia are not known. There is also a lack of clarity about environmental factors, except insofar as complications in pregnancy are known to slightly increase the risk. It is impossible to predict the course of schizophrenia; a statistical relationship exists between the severity and certain symptoms but this provides an inadequate basis for making predictions about individual patients.

Research into the possibility of predicting the occurrence of schizophrenia has shown that future patients generally display abnormalities in neuropsychologicial tests more often than control persons. These abnormalities are not specific for the disease and even occur relatively frequently in people who do not subsequently develop schizophrenia or related disorders. Investigation of other abnormalities, for example by means of brain-imaging techniques, also failed to produce results that could be used to predict the occurrence of schizophrenia.

Research conducted elsewhere frequently showed a long period between the onset of the first psychosis and the start of treatment. In this advisory report 'first psychosis' means the first psychotic symptoms suffered by the patient, and not therefore the first diagnosis of 'psychotic' made by a medical practitioner. Some researchers assume that the duration of the period between the first psychosis and treatment affects the final result; however this assumption is contested. On average, the final result is worse, if there is a longer period before the start of treatment. However, it is not known whether this is a causal link. It may be based on a common social factor, for example, because patients with a poor prognosis are more likely to isolate themselves from the environment. A prospective study has started in Scandinavia that may provide a decisive answer to this.

Apart from the possible effect of early treatment on the final course of the disease, early treatment is also of direct importance for patients and their relatives in order to reduce the duration and severity of the psychosis and to limit possible damage to social relationships. However, there is a lack of data about the length of time between the initial psychosis and treatment in the Netherlands.

Conclusions and recommendations

No characteristics are known that could form the basis for predicting with reasonable accuracy which adolescents are likely to subsequently develop schizophrenia or a related disease, such as schizophreniform or schizo-affective disorders. Research into the possibility of making such predictions has produced insufficient results. Moreover, investigation also leads to many false positives, i.e. people who will not subsequently develop the disease. Likewise, if a high risk is suspected on the grounds of heredity and behaviour, it is not possible to predict whether or when the disease will occur.

* The publication by the Netherlands Psychiatric Association of guidelines on the use of antipsychotic drugs in the treatment of schizophrenic psychoses has addressed the need for guidelines on treating schizophrenic patients.
* There is a lack of data on the average duration of the period between the onset of the first psychosis and the commencement of treatment in patients with schizophrenia and related disorders in the Netherlands, and on the nature of a possible link between the duration and course of the disease.

The report leads to the following recommendations:

* It would be highly inadvisable to conduct (trial) population screening, in view of the inability to predict the occurrence of schizophrenia and related disorders with reasonable accuracy, the burden any such prediction would place both on the people who eventually develop the disease and those who do not, and the limited likelihood of being able to have any therapeutic effect on the disease.
* In general, the guidelines recently published by the Netherlands Psychiatric Association on treating patients with schizophrenia and schizophreniform disorders should be followed.
* Research is required into the duration of the period between the onset of the first psychosis and the commencement of treatment in patients with schizophrenia and related disorders in the Netherlands; depending on the results of that research, measures (or further research) could be considered for influencing this duration.