Schizophrenia can severely affect quality of life for those afflicted, as well as family and friends. Successful treatment relies on a robust support system, but support can often center on around-the-clock care. A study provides insight into additional health problems that can complicate treatment. The study, conducted by researchers from Denmark’s Aarhus University, examined the connection between schizophrenia and an increased likelihood of developing autoimmune diseases like multiple sclerosis and psoriasis. The researchers believe that infections may be an important part of the development of autoimmune diseases in schizophrenics. The findings build on previous research showing that those with autoimmune diseases like type 1 diabetes, psoriasis and hepatitis are at an increased risk of developing schizophrenia. The new study, however, shows that the relationship goes both ways as those with schizophrenia are also at an increased risk of developing an autoimmune disease. This may be particularly true if they experience a severe infection. Schizophrenia is characterized by paranoid behaviors, hearing voices, hallucinations and fears that someone is reading their minds. In many cases, the patient may become withdrawn and disconnected from loved ones. The study authors utilized data from Danish hospitals, the Danish Civil Registration and the nationwide Danish Psychiatric Central Research Register to gather information on nearly four million people between 1987 and 2010. The researchers identified 39,364 people as having schizophrenia. In addition, there were 142,328 individuals identified as having an autoimmune disease. The researchers discovered that when a person has schizophrenia they are 53 percent more likely to develop an autoimmune disease. In addition, among those that have a schizophrenia diagnosis and have experienced a hospitalization for a severe infection, there is a 2.7 times increased risk of developing an autoimmune disease. Six percent of all schizophrenic patients also have an autoimmune disease that requires hospitalization. Given that the study does not account for the cases in which a general physician is treating the patient, or cases in which the person has not yet been diagnosed, psychiatrists need to be watchful for signs of physical illness in patients diagnosed with schizophrenia. The researchers identified a connection between schizophrenia and autoimmune disease, but the study was not designed to provide an explanation for the connection. The researchers believe, because of the data, that there is support for infections as a big contributor to the connection. When there is an infection, the body’s immune system reacts by producing antibodies, which not only respond to the infection but can also break down healthy tissue in the body, leading to an autoimmune disease. The researchers offer another explanation: symptoms may be diagnosed as schizophrenia that are instead, or in addition to, signs that there is an autoimmune disease developing. Another possible explanation centers on genetics and lifestyle. The study also sought to determine whether members of the family with schizophrenia are at an increased risk for developing an autoimmune disease. The researchers hope to continue their examination by combining the registry data with biological measurements, including blood samples, in order to better understand the connections between genetic and environmental causes in these disorders.