Researchers have long known that women who get an infection such as the flu while pregnant have a slightly increased chance that their baby will develop schizophrenia in adulthood. However, because so many different types of infections, from bacteria to viruses to parasites, all increase the offspring's risk of schizophrenia, researchers think that activation of the immune system in general—rather than the specific pathogen causing the infection—is responsible. A new study, based on a large sample of people in Finland and published online June 27th in The American Journal of Psychiatry, strengthens this idea, and adds to the ever-growing pile of evidence implicating the immune system in schizophrenia.
The results are the latest findings from the Finnish Prenatal Studies, a large project that collected blood samples from all pregnant women who gave birth in Finland from 1983-1998, and followed the health of the infants all the way into adulthood. A team of researchers from Columbia University including 2013 NARSAD Young Investigator Grantee Sarah E. Canetta, Ph.D., and former NARSAD Grantees Christoph Kellendonk, Ph.D., (2002 and 2008) and Andre Leif Sourander, M.D., (2008) has tapped into this wealth of data to investigate the link between inflammation and schizophrenia.
The researchers found that, compared to the blood from moms whose offspring did not develop schizophrenia, the blood from the women whose progeny were later diagnosed with schizophrenia had higher levels of an inflammatory protein. Although not definitive proof, these results strongly suggest that higher levels of maternal inflammation during pregnancy are somehow involved in the development of some cases of schizophrenia, and may have implications for treatment and prevention of the illness.