News: Encephalitis survivors found to have an increased risk of dementia, study finds

Patients who survived encephalitis had an increased risk of developing dementia and related diagnoses when compared with matched control individuals, a study posted in the Journal of Neurology found.

Researchers conducted a retrospective cohort study, including a total of 53,379 patients diagnosed with encephalitis between January 2005 and June 2026. Each encephalitis cohort was compared with age-stratified control cohorts, using a 1:1 propensity score matching based on demographics and comorbidities including diabetes mellitus, hypertensive diseases, heart diseases, chronic kidney disease, and cerebral infarction.

It was found that patients with encephalitis had significantly higher risk for dementia and related diagnoses compared with controls. Among individual diagnostic categories, older adults showed significantly elevated risk across all dementia subtypes, including Alzheimer disease and other degenerative diseases of nervous system, vascular dementia, dementia in other diseases, and unspecified dementia.

Non-infectious/post-infectious inflammatory encephalitis and viral encephalitis subtypes showed the highest dementia risk compared with matched controls. Bacterial encephalitis showed no significant association with dementia outcomes.

"These findings highlight the importance of long-term cognitive monitoring for encephalitis survivors across all age groups and support the use of encephalitis as a model to study acute brain inflammation driven neurodegeneration," the authors of the study wrote.

Editor’s note: To read the full study, click here. To read additional coverage from Medscape, click here.