PM2.5 is linked to Alzheimer's syndrome and delirium: a mendelian randomization analysis.

Background: Increasing air pollution has drawn our attention to particulate matter (PM2.5), which has been shown to correlate significantly with respiratory and cardiovascular systems. However, whether PM2.5 is causally associated with Alzheimer's syndrome or delirium is unclear.

Methods: We retrieved the genetic summary data of PM2.5 from genome-wide association studies (GWAS). The genetic information for Alzheimer's disease was obtained from the IEU OpenGWAS project, and that for delirium was obtained from FinnGen. We used two-sample Mendelian randomization analysis (MR) to associate PM2.5 with Alzheimer's disease or delirium.

Results: The odds ratio (OR) for Alzheimer's disease was 0.996 with a p-value of 0.443 using the inverse variance weighted algorithm, and the OR associated with the outcome variable of delirium was 0.393 with a p-value of 0.343.

Conclusion: With the exclusion of confounding factors, our findings do not support a genetic association between PM2.5 and Alzheimer's disease or delirium. Further population-based and experimental studies are needed to dissect the complex correlation between PM2.5 and Alzheimer's disease or delirium.