Shingles tied to cognitive decline

Here's more incentive to get a shingles vaccine if you haven't already: a new Harvard-led study has found that having shingles — the reactivation of the chickenpox virus — is linked to an increased risk of developing cognitive decline years later. Researchers evaluated the health records and periodic questionnaire answers of more than 149,000 people, middle-aged and older, followed for more than 14 years. Compared with those in the study who did not have shingles, those who did had a 20% higher risk of later developing what the study called subjective cognitive decline (SCD): they noticed that they were having trouble with remembering recent events or a short list of items, following instructions, or recalling the plot of a TV show, for example. People with SCD are at greater risk for developing dementia. Researchers also found that the risk for SCD among participants was significantly higher in men who were carriers of a particular Alzheimer's gene (APOE4) and in people who were not vaccinated against shingles, although these results were not conclusive. The study, published online Aug. 14, 2024, by Alzheimer's Research & Therapy, was observational and doesn't prove definitively that shingles causes SCD. However, increasing evidence suggests that long-term, low-grade infection of the brain, such as by the shingles virus, may be one cause of Alzheimer's disease. The shingles vaccine (Shingrix) is effective at warding off shingles and is recommended for everyone ages 50 or older.

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