A study from the University of Helsinki, published in PLOS Medicine and reported by The Sun, examined more than 62,000 people with dementia and compared them with over 300,000 without the condition.
The researchers found that nearly half of those with dementia had previously had at least one of 29 specific diseases.
The most common included stroke, brain injuries, and type 2 diabetes.
These conditions often occurred several years before dementia was diagnosed, suggesting a possible link between overall physical health and brain function.
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The role of infections
The study also showed that serious infections were part of the picture.
In particular, bacterial infections requiring hospital treatment were more frequently observed in individuals who later developed dementia.
A common urinary tract infection, cystitis, for example, may be associated with an increased risk of dementia. The risk was approximately 19 percent higher in individuals with these infections.
The infections typically occurred five to six years before diagnosis. The association remained even after researchers accounted for other diseases.
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The results also showed that the link was slightly stronger in men and even more pronounced in individuals who developed dementia before the age of 65.
An uncertain study
The study cannot prove that infections directly lead to dementia, as the research is based on observations rather than experiments.
The researchers also lacked information on how the infections were treated.
Nevertheless, the findings suggest that preventing and treating infections in a timely manner may be important.
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Sources: The Sun and PLOS Medicine.
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