Does Having an Infection Increase the Odds of Developing Mental Disorders?

While prior studies show that people who are hospitalized due to severe infections have an increased risk of developing schizophrenia and depression, a larger study found that all infections, no matter how minor, can increase your chances as well. 

The study was published in the journal Acta Psychiatrica Scandinavica, and aimed to discover the correlation between infections treated with antibiotics, antiviral drugs, and other medicines against fungal diseases and/or parasites in people born in Denmark between 1985 and 2002 with diagnosed schizophrenia and depression between 1995 and 2013. 

After intense data collecting, the findings suggested inflammatory responses due to infections (even the minor ones) can have a large impact on the brain, which might be the first step towards developing a long-term mental disorder. 

“Our primary finding was that the risk of both schizophrenia and depression was increased in those who had infections,” lead author Ole Köhler-Forsberg, from Aarhus University and Aarhus University Hospital said, “The risk was increased in a dose-response correlation, which means that the risk was higher depending on the number of infections.” 

It is also possible that antibiotics themselves increase the risk of mental disorders, seeing as they have a large effect on intestinal compounds, which directly communicate with the brain. 

As senior researcher Michael Eriksen Benros said, “Our findings may [also] be caused by genetic aspects, which is to say that some people have a higher genetic risk for getting more infections as well as a mental disorder.”