Shingles is caused by the reactivation of the chicken pox virus, leading to a painful, itchy rash on the skin. The chance of getting shingles increases with age, as does the risk of severe side-effects. The Welsh shingles vaccination programme was launched on 1 September 2013, offering free vaccination against shingles to anyone aged over 70 and below 80 years. This age cutoff was determined based on the efficacy of the vaccine, which was shown to be lower in adults aged 80 and over. The stringent eligibility cut-off for the vaccination programme allowed researchers to compare the incidence of dementia in two similar groups of older adults: people who were born on or after September 2, 1933 (and were eligible for shingles vaccination) and people who were born just one week earlier, and were therefore not eligible for vaccination. According to their analysis of electronic health records from 282,541 people in Wales, receiving a vaccination for shingles may reduce the risk of developing dementia.
In their study, which was recently released on the medRxiv preprint server, a team of researchers led by Pascal Geldsetzer at Stanford University (California, USA) analysed the electronic health records of 296,603 people born between 1925 and 1942, evaluating several health outcomes including the diagnosis of dementia. Just under half of those who were eligible received the shingles vaccine in the 7-year period that was analysed. Statistical analyses of health data showed that people receiving shingles vaccination were 19.9% less likely to develop dementia, compared to people who did not receive the vaccine. Closer inspection of the health records revealed that the vaccine’s effect on dementia diagnosis was much greater in women than in men. However, dementia experts have cautioned that clinical trials are now needed to confirm the observed effect, and eliminate possible causes of bias that may affect the validity of the results. Read the article on medRxiv:
https://www.medrxiv.org/content/10.1101/2023.05.23.23290253v1.full-text
