Striking similarities between patients with multiple sclerosis and a type of schizophrenia suggest the disorders are related, according to a review of a number of studies.

Dr. Boris M. Arneth wrote the article, “Multiple Sclerosis and Schizophrenia.” It was published in the International Journal of Molecular Sciences.

MS is a chronic disease that affects the central nervous system, while schizophrenia is primarily considered a psychiatric disease. Patients with MS are reported to be at an increased risk of developing schizophrenia and bipolar disorder.

There are similar abnormalities in the immune systems of those with MS and schizophrenia.

Experts suspect one of the causes of both illnesses is the immune system turning against the body and damaging healthy tissues and organs. Scientists have found brain tissue damage in people with MS and schizophrenia.

Autoantibodies, or antibodies that damage the body’s own cells, are present in MS and in a type of schizophrenia, although they have different targets in the brain.

Other similarities of MS and schizophrenia are that both typically develop during early adulthood, and both appear to be triggered by certain infections.

There are striking differences between MS and schizophrenia, too, however. For instance, MS affects women more than men, but schizophrenia affects the genders equally. Another difference is that MS affects whites more than blacks, while schizophrenia is more common in blacks than whites.

Experts estimate that 2.2 million Americans have schizophrenia and 400,000 MS.

Both diseases can occur in the same person, or in the same family. Arneth called for more studies on families. One reason is to see how often it happens. Another is to learn whether family members with either MS or schizophrenia share inherited traits.

“There may be hereditary elements that predispose patients to developing not only MS or SCZ [schizophrenia] separately but also both diseases simultaneously, as both diseases can occur in the same family,” Arneth wrote. “This would be an interesting point for future studies to investigate.”

The review turned up “similarities and differences in genetic, immunological, seasonal, geographical, and gender-related risk factors” for the two diseases, he said. “The findings suggest that subgroups of these two diseases may belong to the same class of disorders.”