Field of Science

Coughs and Sneezes Spread.....Schizophrenia ?

There has been a recent article in Scientific American which links schizophrenia to Infection by a disease, such as influenza. Now this may seem strange to you, but it is not completely bollocks.
It is already well known that if a mother gets especially stressed during preganacy, her stress hormones can cross the placenta and this can cause problems for the baby.

When you get an infection, your immune system produces cytokines, which can trigger stress through the hypothalamo-pituitary-adrenal axis, which can cause an upregulation in stress hormones.
So essentially, when the baby recieves these hormones, it is essentially bieng told that the world outside is a stressful place. Because of this, it changes the sensory apparatus in it's brain to adapt to this situation. It has been shown that animals whom are born in stressful pregnancies have a tendency be more alert to stressful stimuli. This means that they generally become more stressed, more easily.[11] This is known as Foetal programming, and is believed to have an effect on many disorders.
It has been hyopothesised that one possible adaptation to this sort of stress is schizophrenia [As written in the Journal of medical hypotheses]. However, there has been no study which has been able to conclusively say that influenza infection causes schizophrenia.
That is mostly because in order to do this, you will have to actually get a statistically significant number of young mothers to agree to be infected with influenza, so that we can see whether the children develop schizophrenia. It just isn't going to happen, and even if you did find the right number of mothers, few researchers would have the patience to wait that long for results. Because of this lack of conclusive evidence, it is still a hypothesis rather than a theory.
There are lots of studies which have tried find correlations between schizophrenia and a variety of factors. One problem with this is that they often look exclusively at schizophrenic patients, and work backwards from there. There was one study that found that a large number of schizophrenic people had mothers who were infected with flu during pregnancy. However, they were not able to show any evidence that the number of mothers infected with influenza was any different from the rest of the population [1] However, there have been some convincing articles which have shown that in years with epidemic influenza, there has been an increase in schizophrenia incidence [2]. However, it could be that the stress induced by the pandemic itself could cause this, and there are flaws to the methodology which have not been adequately been addressed. [3]
The most strongest factor at the moment i.e. the one you should worry about the most is genetics. it is possible to screen people genetically, and give them a probability telling them how likely they are to get schizophrenia.
But this does not explain everything. There are still people who get schizophrenia without having these genes, and there are people who have these genes that don't. It is possible that infection could explain this, but it's still only a hypothesis at the moment, and one of many [4][5][6][7].
The fact that schizophrenia is such a hard to define disorder is not helping either. It is possible that it is an umbrella term for a number of disorders which show the same symptoms. it is likely that there are distinctly different diseases , like "Genetically Induced Schizophrenia" , "Stress Induced Schizophrenia" , "Perinatal Infection-Induced Schizophrenia" or "Genetically, Perinatal Infection and Stress induced Schizophrenia", which can interract with eachother to make schizophrenia development more likely.
Because of this, it is unlikely that there will be any definate cure for everybody, as people who have schizophrenia often have it as a result of different factors.
However, this is not a problem for Big Pharmaceutical companies, because they prefer to treat symptoms rather than create cures. ("if you cure someone, they won't come back for another prescription")
And to be honest, this is the only appropriate way to control schizophrenia until we actually can determine the root causes.
Should we panic about Influenza causing schizophrenia?
No, not yet. At the moment there is is a much greater level of evidence showing that genetics correlate better to schizophrenia [8]. The evidence that anxiety during pregnancy can cause schizophrenia in children is also higher. So panicking itself would cause things to worsen. If there are any pregant women reading this blog, I have just increased their chances of giving birth to someone who will be schizophrenic in later life [9]. Read that again if it doesn't scare you.
Okay, i'm being overdramatic here, but you should get my point. You should not panic about this. But don't take my word for it. I have supplied a long list of references, and it is likely that I have missed out some important points.If you can find the time read through them yourself, and make up your own mind.


[1]Exposure to Influenza in the Womb May Increase Risk of Schizophrenia by Amanda Barrett, MA @
[3] "On the plausibility of ''The neurodevelopmental hypothesis'' of schizophrenia" by Weinberger DR in NEUROPSYCHOPHARMACOLOGY Volume: 14 Issue: 3 Pages: S1-S11 Supplement: Suppl. S Published: MAR 1996
[4] "Maternal household crowding during pregnancy and the offspring's risk of schizophrenia" by Kimhy D (Kimhy, David), Harlap S (Harlap, Susan), Fennig S (Fennig, Shmuel), Deutsch L (Deutsch, Lisa), Draiman BG (Draiman, Benjamin G.), Corcoran C (Corcoran, Cheryl), Goetz D (Goetz, Deborah), Nahon D (Nahon, Daniella), Malaspina D (Malaspina, Dolores) in Schizophrenia Research Volume: 86 Issue: 1-3 Pages: 23-29 Published: SEP 2006
[5] "Season of birth and schizophrenia in Northeast Brazil - Relationship to rainfall" by Messias E (Messias, Erick), Mourao C (Mourao, Carine), Maia J (Maia, Juliana), Campos JPM (Campos, Joao Paulo Mendes), Ribeiro K (Ribeiro, Kersia), Ribeiro L (Ribeiro, Luciana), Kirkpatrick B (Kirkpatrick, Brian) in JOURNAL OF NERVOUS AND MENTAL DISEASE Volume: 194 Issue: 11 Pages: 870-873 Published: NOV 2006
[6] "Schizophrenia-proneness, season of birth and sleep: Elevated schizotypy scores are associated with spring births and extremes of sleep" by ): Reid HM (Reid, Howard M.), Zborowski MJ (Zborowski, Michael J.) in PERSONALITY AND INDIVIDUAL DIFFERENCES Volume: 41 Issue: 7 Pages: 1185-1193 Published: NOV 2006
[7] "Biological hypotheses of schizophrenia: Possible influences of immunology and endocrinology" by Sperner-Unterweger B in FORTSCHRITTE DER NEUROLOGIE PSYCHIATRIE Volume: 73 Pages: S38-S43 Supplement: Suppl. 1 Published: NOV 2005
[8] "Linkage of a neurophysiological deficit in schizophrenia to a chromosome 15 locus" by Freedman R, Coon H, MylesWorsley M, OrrUrtreger A, Olincy A, Davis A, Polymeropoulos M, Holik J, Hopkins J, Hoff M, Rosenthal J, Waldo MC, Reimherr F, Wender P, Yaw J, Young DA, Breese CR, Adams C, Patterson D, Adler LE, Kruglyak L, Leonard S, Byerley W in PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Volume: 94 Issue: 2 Pages: 587-592 Published: JAN 21 1997
[9] "Higher risk of offspring schizophrenia following antenatal maternal exposure to severe adverse life events" by Khashan AS (Khashan, Ali S.), Abel KM (Abel, Kathryn M.), McNamee R (McNamee, Roseanne), Pedersen MG (Pedersen, Marianne G.), Webb RT (Webb, Roger T.), Baker PN (Baker, Philip N.), Kenny LC (Kenny, Louise C.), Mortensen PB (Mortensen, Preben Bo) in ARCHIVES OF GENERAL PSYCHIATRY Volume: 65 Issue: 2 Pages: 146-152 Published: FEB 2008

[11] "Prenatal glucocorticoids and long-term programming" in EUROPEAN JOURNAL OF ENDOCRINOLOGY Volume: 151 Pages: U49-U62 Supplement: Suppl. 3 Published: NOV 2004

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