Severe infections may quietly raise the risk of dementia later in life, a new study suggests, highlighting an often-overlooked link between physical illness and brain health.

Researchers analysing health records from Finland found that older adults who had serious infections such as urinary tract infections or other bacterial illnesses were more likely to develop dementia years later. The study reviewed data from more than 62,000 people with dementia and compared them with over 300,000 without the condition.

Notably, the increased risk remained even after accounting for other health problems, suggesting infections themselves may play a role. In many cases, these infections occurred five to six years before dementia was diagnosed.

Experts believe such illnesses might speed up underlying damage in the brain, though they stress the findings do not prove direct cause and effect.

The authors say better prevention and timely treatment of infections could potentially delay or reduce dementia risk, but further studies are needed to confirm this possibility.