Numerous studies have shown that inhibition of COX-1 and COX-2 by NSAIDS can reduce the risk of AD [35,36,37,38], however, not all studies have shown such positive results [39,40] and the effect may depend on the parameters employed in each study, such as the NSAIDS used, the stage of AD when treatment was begun, as well as the diversity of the population involved in the study. Here, PTGS2 is linked to Alzheimer disease.