Association between rosacea and dementia: A systematic review and meta-analysis

Rosacea, a chronic inflammatory skin condition, has been increasingly recognized as a potential systemic disorder, with the skin–brain axis providing a biological basis for exploring its link to neurocognitive diseases; however, existing epidemiological evidence remains inconsistent. This systematic review and meta-analysis systematically searched PubMed, Embase, Web of Science, and the Cochrane Library from inception to March 16, 2026, for observational studies reporting associations between rosacea and all-cause dementia, Alzheimer’s disease (AD), vascular dementia, and Parkinson’s disease dementia. A random-effects model was used to pool relative risks (RRs) with 95% confidence intervals (CIs). Three observational studies (two cohort and one case–control) comprising 6,198,526 participants were included. The pooled analysis showed no significant association between rosacea and all-cause dementia (RR = 1.22, 95% CI 0.99–1.50, P = 0.065), with substantial heterogeneity ( I ² = 96.2%). Subgroup analysis based on two studies revealed a significant association with AD (RR = 1.21, 95% CI 1.08–1.36, P < 0.01, I² = 0%). Sensitivity analyses supported the robustness of the all-cause dementia and AD findings. In conclusion, while rosacea was not associated with all-cause dementia, a significant association with increased AD risk was observed, suggesting shared inflammatory or vascular pathophysiological mechanisms that warrant further investigation.