Hospitalization with infections and risk of Dementia: a systematic review and meta-analysis.

BACKGROUND: Dementia affects more than 50 million people worldwide, with 10 million new diagnosis each year. The link between hospitalization with infections and risk of Dementia is unclear. We conducted a meta-analysis on the association between hospitalization with infection and risk of Dementia. METHODS: We searched MEDLINE and Embase from inception to March 31, 2025 to identify cohort studies comparing the frequency of Dementia in patients hospitalized with infections with those without. We computed hazard ratios (HR) for each study and pooled the results using a random-effects meta-analysis. RESULTS: Out of 1900 studies that were screened initially, 16 studies comprising 4,266,276 patients were included for analysis. Hospitalization with infection was associated with an increased risk of all-cause Dementia (HR: 1.83, 95% CI: 1.58-2.13, p < 0.0001), Alzheimer's Disease (AD) (HR: 1.60, 95% CI: 1.23-2.08, p < 0.001) and Vascular Dementia (HR: 3.68, 95% CI: 2.16-6.27, p < 0.001). Among the infections, having Sepsis (HR: 1.78, 95% CI: 1.53-2.08) was associated with the highest risk of all-cause Dementia, followed by Pneumonia, Urinary Tract Infections, Skin and Soft Tissue infections. CONCLUSIONS: Our meta-analysis showed that hospitalization with infection was associated with increased risk of Dementia. Sepsis carried the highest risk, followed by Pneumonia, Urinary Tract Infections, Skin and Soft Tissue infections.