Schizophrenia Daily News Blog

Steps to Schizophrenia prevention

Prevention of Schizophrenia - Can it Be Achieved?
Cheng Lee, Thomas H. McGlashan and Scott W. Woods
CNS Drugs 2005; 19 (3): 193-206

This is a very well written recent review article that takes a look at the idea of preventative psychiatry. Is/Will it be possible to detect schizophrenia at an early enough stage to prevent the full illness? The article talks about the financial and social impacts of schizophrenia, understanding the role of risk factors, stages of the illness and finally what possible steps might be possible before and after detection of the onset of symptoms.

Costs of schizophrenia: According to the article, the costs of schizophrenia in 1990 (for society) were over 30 BILLION dollars. Half of that was spent on treatments and the other on lost work/decreased production and other associated costs. The estimate was to nearly double by 1995. Current figures are unavailable, but the costs are expected to be much higher still.

Prevention of Schizophrenia:
In beginning a discussion regarding prevention of illness, it is helpful to review the different types of prevention one usually considers. The first is primary prevention. This is the type of prevention that seeks to eliminate the disease well before it starts, usually at a population level. In schizophrenia it involves continued research into the genetics and other causes of schizophrenia such that one could predict risk more effectively and identify people who are likely to be at increased risk before they have problems. Secondary prevention involves mitigating difficulties already encountered. With schizophrenia, this means making interventions in people labeled as having “prodromal” symptoms of the illness. This means that they may be having certain, often nonspecific, symptoms that often relate to an eventual onset of schizophrenia. With increased refinement in the future, we may be able to more specifically target for earlier treatments those who are in the prodromal phase of the illness to prevent the downward spiral often seen with severe illness. Lastly, there is tertiary prevention. This involves educating the public about schizophrenia such that the general awareness is helpful in identifying potential consumers and is more understanding of the issues that face those with schizophrenia.

Primary Prevention strategies:
The authors discuss the role of obstetrical complications in understanding the cause and first possible opportunity for primary prevention. While certain complications have been linked to schizophrenia, there has not been good conclusive evidence that obstetrical complications cause schizophrenia. However, the benefit of trying to reduce complications has more than just psychiatric implications. Additionally, the benefits that these efforts might have are more likely to be seen in developing countries and a places with higher rates of these types of complications.

Other primary measures include sharpening our genetic theories. Right now there are several genes that are thought to be involved. It is a very complicated picture however, as even identical twins (who have the same genes) only have about a 50% chance of both having schizophrenia if one twin has it. That means that there is more than just a genetic explanation. However, using other factors, it may ultimately be possible to determine who are the highest risk children and make sure that they are given the resources needed to help prevent the onset of schizophrenia.

The authors also discuss looking at impaired attention as a predictor of future outcome. Using particular markers of attention, there have been findings that show that differences as early as 12 years old can be used to predict outcome.

Secondary Prevention strategies:

The main theme of secondary prevention is recognition in the prodromal stage of the illness. That means to pick up on symptoms that are causing difficulty but have not led to the full syndrome and a conclusive diagnosis of schizophrenia. Many people with prodromal symptoms develop other psychiatric illness or no illness at all. The symptoms that are considered prodromal are generally not specific to schizophrenia and that causes the wide variation of outcome. However, it is important to begin to understand who might benefit from treatment at an earlier stage and who might never need full schizophrenia treatment. There are several different rating scales that can be used to assess for the severity of prodromal symptoms. Often that data is put together with family history and other factors such as attentional testing and other neuropsychiatric tests to help make a prediction.

There is data that suggests that the duration of untreated psychosis (DUP) relates to overall outcome. The shorter the DUP is, the better the prognosis in certain aspects of the illness. This leads people to consider treating patients before they are severely psychotic in order to minimize the DUP. There is still controversy though to the best time to initiate treatment however. It has been shown that longer DUP is usually seen in people who have prominent negative symptoms, lower level of functioning before onset of symptoms and in those with a more subtle onset to their psychosis. There have been some industry sponsored studies recently using antipsychotics to treat prodromal symptoms. While there have been the usual and expected side effects, there also has been a decrease rate of conversion to psychosis in the small studies. In addition, treatment of the prodrome is not with out risk. First, it is possible that the patient will not develop schizophrenia and wouldn’t otherwise need the medication. Perhaps they would respond to aggressive cognitive therapy or another treatment modality. Also, once someone receives a diagnosis, they carry it with them. There are still stigmas associated with mental illness and therefore it is with caution that one prematurely would want to put a label on someone. However, preventing the syndrome would likely lessen the amount of stigma that one has to face because there would be less unusual behavior and less of a chance that they would stand out from a crowd based on the illness.

Tertiary prevention strategies:

The strategies in this part of the paper refer to aggressively treating people in the midst of their first major episode such that they have a decreased progression of the illness. The goal is to also decrease the DUP such that the overall prognosis can be improved. There is reason to believe that early, aggressive treatment is helpful. First episode patients generally require less medication and are more responsive to treatment. While some disagree, most say that it is helpful for protection sake to begin chronic antipsychotic therapy. Without such therapy, it is estimated that 80% of patients will have a relapse. However, individual variation exists such that a blanket statement regarding treatment is not possible.

Conclusion:
Schizophrenia is a devastating disease. There are several points in the development of the syndrome when one can be brought to clinical attention. Further research must be done to help identify the best treatments at the various stages of the illness. Ultimately, with such therapies, we’ll be able to decrease the DUP for more people and improve the prognosis for those who have already become psychotic, while also helping prevent more episodes of psychosis in the first place.

Supported by grants to Dr McGlashan from the National Alliance for Schizophrenia and Affective Disorders (NARSAD) and from the UK National Institute of Mental Health (MH01654). Dr McGlashan has also received research support from Eli Lilly Company. Supported by grants to Dr Woods from the Donaghue Foundation and MH61282 from the US National Institutes of Health. Dr Woods has also received research support from pharmaceutical companies including Eli Lilly, Janssen and Bristol-Myers Squibb.

Click here to find the article on PubMed