People with previous infections are nearly three times more likely to develop dementia compared to those without infections, and more infections are tied to a greater risk for neurodegeneration, a new study finds.
The report was published Tuesday in Nature Aging. Authors say that preventing infections may lower the burden of conditions such as Alzheimer’s disease and other dementias.
Even after researchers accounted for pre existing diseases, mental disorders and socioeconomic deprivation, the link between viral, bacterial, parasitic and other infections persisted with regard to developing neurodegenerative diseases, including vascular dementia.
Data was derived from 1,742,406 people in New Zealand who were born between 1929 and 1968. People were between 61 and 75 when diagnosed with infection, and ranged from 72 to 82 when they were diagnosed with dementia. Researchers followed them from 1989 to 2019. During the study span, 26.7% of people had infections, and 2.1% were diagnosed with dementia. People with more infection-related hospital admissions across a 20-year exposure period were more likely to be diagnosed with dementia in the 10-year follow-up period, the data showed.
“We identified associations with multiple infection types, suggesting that preventing any type of infection might benefit cognitive health. It is important to note that these data cannot confirm causality,” the authors wrote.
Other research has linked infections like herpes simplex virus, Helicobacter pylori, hepatitis C, and flu with dementia. The authors noted that they found a link with dementias across more infection types, so they think the inflammation or another process occurring during an infection may be the culprit of the neurodegeneration instead of the individual pathogen.
The infections studied were treated but still largely followed by dementia, which shows the importance of preventing infection, the authors noted.
“Results from our study and others raise the question of whether infections should be considered a key modifiable risk factor for dementia, alongside other established factors such as depression and physical inactivity,” the authors wrote.
