A recent article published in a leading psychiatry journal, JAMA Psychiatry, has shown that pregnant mothers’ exposure to the influenza (flu) was associated with a nearly 4X increase in risk to their child eventually developing bipolar disorder in adulthood. These findings add to mounting evidence of possible shared underlying causes and illness processes with schizophrenia, which some studies have also linked to prenatal exposure to influenza. Bipolar disorder, historically called manic depressive disorder, is a mood disorder where the sufferer can experience episodes of a frenzied state known as mania (or hypomania), typically alternating with episodes of depression. It can be treated with medications and psychotherapy (especially cognitive therapy), but more difficult cases require the individual to be voluntarily or involuntarily institutionalized until the mood changes can be reduced or eliminated.
“Prospective mothers should take common sense preventive measures, such as getting flu shots prior to and in the early stages of pregnancy and avoiding contact with people who are symptomatic,” said Alan Brown, M.D., M.P.H, of Columbia University and New York State Psychiatric Institute, one of the authors of the study. “In spite of public health recommendations, only a relatively small fraction of such women get immunized. The weight of evidence now suggests that benefits of the vaccine likely outweigh any possible risk to the mother or newborn.”
According to the article, there have been indications that there was a strong association between maternal influenza and several mental disorders, including schizophrenia and bipolar disorder. This study, using information from the Kaiser-Permanente health records, one of the most detailed and complete in the world, along with other child health and development databases, the researchers were able to include more cases with detailed information on maternal flu exposure. Using these databases, the researchers were able to track nearly a third of all children born in a northern California county during 1959-1966, researchers followed, 92 who developed bipolar disorder, comparing rates of maternal flu diagnoses during pregnancy with 722 matched controls. This is one of the best ways to examine epidemiological data retrospectively to gain insight into relationships between various diseases.
The nearly fourfold increased risk in bipolar disorder related to an influenza infection at any time during pregnancy, although there was evidence suggesting slightly higher risk if the flu occurred during the second or third trimesters. Furthermore, the researchers linked flu exposure to a nearly sixfold increase in a subtype of bipolar disorder with psychotic features, the most serious form of the disorder.
In a previous study, also authored by Dr. Brown, using a related northern California sample, found a 3X increase in risk for schizophrenia also associated with maternal influenza during the first half of pregnancy. Brown further stated that, “future research might investigate whether this same environmental risk factor might give rise to different disorders, depending on how the timing of the prenatal insult affects the developing fetal brain.” Finally, there is some, slightly less conclusive evidence that flu during pregnancy is associated with autism spectrum disorders.
Moreover, flu vaccines for pregnant mother is safe. A recent study concluded that women who had the seasonal flu vaccine during pregnancy actually had better neonatal outcomes, that is, healthier babies, than those who did not.
So, the vaccine is safe for pregnant mothers. And getting the vaccine might prevent several mental health disorders that arise from women who catch the flu during pregnancy. If it were a small difference between mothers who were vaccinated and those who caught the flu, then maybe this isn’t an important issue. But catching the flu increases the risk of bipolar disorder for the child by FOUR TIMES. This is simply an easy choice. Get the vaccine to not get the flu so you reduce the risk to your developing fetus. The evidence is there. Don’t ignore it.
- Atladóttir HÓ, Henriksen TB, Schendel DE, Parner ET. Autism after infection, febrile episodes, and antibiotic use during pregnancy: an exploratory study. Pediatrics. 2012 Dec;130(6):e1447-54. doi: 10.1542/peds.2012-1107. Epub 2012 Nov 12. PubMed PMID: 23147969.
- Brown AS, Patterson PH. Maternal infection and schizophrenia: implications for prevention. Schizophr Bull. 2011 Mar;37(2):284-90. doi: 10.1093/schbul/sbq146. Epub 2010 Dec 6. Review. PubMed PMID: 21134972; PubMed Central PMCID: PMC3044639.
- Parboosing R, Bao Y, Ling S, Schaefer CA, Brown AS. Gestational Influenza and Bipolar Disorder in Adult Offspring. JAMA Psychiatry. 8 May 2013. doi:10.1001/jamapsychiatry.2013.896
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