Prenatal infection and immune activation is one line of enquiry in schizophrenia research.Associations have been reported with maternal antibody to influenza, rubella, toxoplasma gondii, and herpes simplex virus type 2. animal research supports the idea that such activations can have impact on brain. Would maternal C Reactive protein be associated with schizophrenia in offsprings?
Sarah Canetta and team of researchers from New York and Finland used data from Finnish Prenatal Study of Schizophrenia to explore this link. Both Finnish national birth cohort and the national case registry are comprehensive in its coverage. All offspring born in Finland from 1983- 1998 were included.
There was a significant association between increasing maternal C-reactive protein and risk of schizophrenia (odds ratio=1.12, 95% confidence interval =1.02–1.24, p=0.02. Magnitude of this association increased when adjusted for covariates like maternal age. Every 1 mg/L increase in maternal C-reactive protein, the risk of schizophrenia was increased by 28%. If mother’s CRP level was abnormal (i.e. above 10 mg/l) the risk increased by odds ratio of 1.58 ( 95% CI=1.04–2.40, p=0.03).But when this was adjusted for various covariates, the difference didn’t reach statistical significance.
This sample had relatively younger ( mean age 23) subjects and it is possible that the observed association is relevant only for early onset schizophrenia.It is also possible that CRP elevation is related to an earlier onset of the disease in persons at risk for other reasons.
Similar results were reported with autism previously , so the risk may not be specific to schizophrenia. It is possible that immune activation primes brain and the interactions with genetic and environmental factors in certain developmental windows might be deciding the outcomes.
Conclusion: Elevated maternal CRP is associated with an increased risk go schizophrenia in offsprings.
Comments: Would reducing infections / inflammations during pregnancy help in reducing incidence of schizophrenia?
Summary of the article:
Canetta S, Sourander A, Surcel HM, Hinkka-Yli-Salomäki S, Leiviskä J, Kellendonk C, McKeague IW, Brown AS.
Am J Psychiatry. 2014 Sep 1;171(9):960-8