Hospitalization for infection linked to higher dementia risk

“I hope I don’t have an infection!”

Hospitalization due to infection may increase a person’s likelihood of developing dementia, according to a large NIA-funded observational study. The researchers found people hospitalized with an infection were more likely to be diagnosed with dementia years later than those who were not hospitalized with infections. The results, published in JAMA Network Open, suggest measures taken to prevent infection may also contribute to dementia prevention.

Previous findings have suggested an association between dementia and certain types of infections, such as systemic and central nervous system infections. Additionally, hospitalization for any reason, but notably for infection and critical illness, has been linked to cognitive decline. Building on these findings, a team led by researchers at the University of Minnesota and an NIA scientist explored the association between hospitalization for infection and dementia by looking at data from the Atherosclerosis Risk in Communities (ARIC) study, an observational study that has followed participants for up to 32 years.

Using data from 15,688 participants who did not have dementia when they entered the ARIC study, the scientists determined whether participants were hospitalized for an infection, and how many subsequently developed dementia three to 20 years later. The research team also investigated whether different types of infections were associated with varying dementia risk.

During the maximum follow-up period of 32 years, 19% of participants were diagnosed with dementia, and 38% were hospitalized with an infection. The researchers determined people who were hospitalized with an infection were 70% more likely to be diagnosed with dementia than those who were not. The types of infections most associated with dementia were blood and circulatory, urinary, and hospital-acquired infections, such as catheter-associated urinary tract infections.

The study’s findings provide evidence that hospitalization with an infection increases one’s risk of developing dementia, underscoring the importance of infection prevention when and if possible. More research on the links between infection and cognition could also lead to improved dementia screening practices.

This research was supported in part by NIA grants K76AG057020 and RF1AG072387 and the Intramural Research Program at NIA (ZIAAG000348).