A team of researchers from the Hebrew University of Jerusalem have successfully associated the Bacillus Calmette-Guérin (BCG) vaccine with reducing the risk of Alzheimer’s.The disease affects one in 10 adults over the age of 65 – a number that is expected to triple by 2030, according to HU. BCG is the vaccine used to treat tuberculosis worldwide. Though in the past it was administered routinely in the United States, it is today mainly used in developing countries or with high-risk populations in Western countries.However, the vaccine has another use, according to Hervé Bercovier of HU’s Department of Microbiology and Molecular Genetics. Bercovier, who led the BCG study with colleagues Charles Greenblatt and Benjamin Klein, said that BCG is also used to treat and cure certain types of bladder cancer. “People with bladder cancer tend to be 70 years or older,” he explained to The Jerusalem Post, “so they are close to the population that has an increased risk for developing Alzheimer’s.”Furthermore, Bercovier explained, BCG has been shown to lower general chronic inflammation. Patients with Alzheimer’s suffer from chronic inflammation in the brain as a result of proteins that improperly unfold inside and outside of the brain.As such, the HU team followed 1,371 bladder cancer patients receiving treatment at HU’s Hadassah-University Medical Center. During follow-up visits, 65 cancer patients had developed Alzheimer’s, a release explained. Those who had not received BCG as part of their treatment had a significantly higher risk of developing Alzheimer’s than did BCG-treated patients: 8.9% (44 patients) as opposed to 2.4% (21).Moreover, when compared with the general – non-bladder cancer – population, people who had never been treated with BCG had a four-fold higher risk for developing Alzheimer’s than did those who were treated with BCG.“There’s data reaching back to the 1960’s that shows that countries treating bladder cancer patients with the BCG vaccine had a lower prevalence of Alzheimer’s disease but it hadn’t been properly analyzed,” said Bercovier.With this study, he said he believes we are closer to understanding the vaccine’s impact.Bercovier noted that the next steps are to reproduce the study in different populations. Then, he said, to prove causality, the team will conduct a formal clinical trial.The findings of this study were published in PLOS ONE.