Severe urinary tract infections may significantly increase the risk of developing dementia in older adults, according to a new study from the University of Helsinki.
Researchers analyzed health data from 62,555 dementia patients and 312,772 controls in Finland, all aged 65 or older. They identified 29 hospital-treated diseases linked to dementia, but only two were infectious: UTIs and other bacterial infections.
After adjusting for comorbidities like diabetes and heart disease, severe infections-especially UTIs-were associated with a 19% higher dementia risk. The average interval between infection and diagnosis was five to six years, suggesting infections may accelerate preclinical neurodegeneration rather than initiate it.
The findings point to systemic inflammation as a possible mechanism. Infections trigger immune responses that, when severe, may damage brain tissue over time.
While no causal link is proven, researchers say preventing serious infections could be a viable strategy for reducing dementia risk alongside established measures like managing blood pressure and staying physically active.