Schizophrenia is a serious mental disorder characterised by withdrawal from reality with delusions, hallucinations, emotional dysregulation and disorganised behaviour. It involves alterations in brain structure and function. The Australia Schizophrenia Research Institute estimates that approximately 1 in 100 people have or will develop schizophrenia during their lifetime. Onset is usually between 15 and 30 years of age and the course tends to be life-long. Of particular concern among schizophrenia sufferers is the alarmingly high suicide rate. The Schizophrenia Research Institute has found that 50% of sufferers attempt suicide with 5% following through. Apart from the profound emotional burden placed on families, the disease is very costly to the Australian community as it is among the top 10 causes of disability.
The cause of schizophrenia is not clear and there appear to be no effective measures to prevent it. Although remedy is available, it is rarely diagnosed early enough to be effective and over 50% of sufferers present with the symptoms for like (Walker et al., 2004). For quite a while psychologists have known that there is a link between maternal illness during pregnancy and the incidence of schizophrenia (Brown et al., 2000), but leading Australian researchers have now proposed that there may even be a link between childhood infection that do not involve the central nervous system and schizophrenia. Liang and Chikritzhs (2012) looked through the medical records of Western Australian males born between 1980 and 1984. Their hospitalisation as a result of infections between birth and three years of age was recorded and schizophrenia diagnosis between the ages of 25 and 29 was noted. The records showed the 426 of those studied has developed schizophrenia. It was found that males with two or more hospitalisations for infections before the age of three had an 80% greater risk of schizophrenia than those who were not hospitalised even after excluding those who may have developed schizophrenia as a result of other factors including abnormal prenatal development, low birth weight and low Apgar scores. These findings were consistent even when the definition of infection was restricted to intestinal and chest infections. Even a single hospitalisation is associated with a greater incidence of the disorder but it is not significantly different from the incidence when there was no hospitalisation during childhood.
One explanation for this link has been proposed by Matsuzawa and colleagues (2001). They note that the brain undergoes rapid growth and development during this critical period of infancy. When such development is disrupted, gene expression is altered, structural growth is impaired and the risk of schizophrenia is increased. Others argue that this link between childhood infection and schizophrenia is strengthened when the infection delays the development of the blood-brain barrier (Hickie et al., 2009).
Regardless of the reasoning behind the association, scientists are now arguing that this finding not only enhances our understanding of the link between adult mental health and childhood disease but it emphasises the need for parents to take protective measures to ensure that their children do not suffer from infections. For example, breastfeeding reduces the risk of infections, and so breastfeeding for a longer period of time may be a protective measure against the development of schizophrenia.
Hence, rather than viewing schizophrenia as an instance of extremely bad luck, parents should take preventative measures even prior to the birth of the child by reducing the chances of maternal illness during pregnancy and the development of infections during infancy. Because the study was conducted on males only there is a need to determine whether these findings to females, but the importance of strengthening the child’s immune system early in life can not be underestimated.
Brown, A.S., Schaefer, C.A., Wyatt, R.J., Goetz, R. Begg, M.D., Gorman, J.M., Susser, E.S. (2000). Mental exposure to respiratory infections and adult schizophrenia spectrum disorders: A prospective birth cohort study. Schizophrenia Bulletin, 26, 287-295.
Hickie, I.B., Banati, R., Stewart, C.H., Lloyd, A.R. (2009). Are common childhood or adolescent infections risk factors for schizophrenia and other psychotic disorders? Medical Journal of Australia, 190, S17-21.
Liand, W., Chikritzhs, T. (2012). Early childhood infections and risk of schizophernia. Psychiatry Research (In Press).
Matsuzawa, J., Matsui, M. Konishi, T., Noguchi, K. Gur, R. C., Bilker, W., Miyawaki, T. (2001) Age-related volumetric changes of brain gray and white matter in healthy infants and children. Cerebral Cortex, 11, 335-342.
Walker, E., Kestler, L., Bollini, A., Hochman, K. M. (2004). Schizophrenia: Etiology and course. Annual Review of Psychology, 160, 1183-1185.