Immunotherapy is the addition of good antibodies into the bloodstream with the intention of boosting the body's defences. It is used as a treatment for immune deficiencies, leukaemia and other types of cancer, anaemia and other diseases. The therapy is thought to have an indirect effect on Alzheimer's disease by targeting beta-amyloid, a protein which forms plaques in the brains of people with Alzheimer's. Researchers from the Mount Sinai School of Medicine in New York looked at the medical records of 847 people given at least one treatment of IVIg (intravenous immunoglobulin) and of 84,700 people not given the treatment over a four-year period. They found that those participants who had received IVIg had a 42% lower risk of developing Alzheimer's disease than those who had not received IVIg. Only 2.8% of those who had had IVIg developed Alzheimer's compared to 4.8% of those not treated.
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