TREM2 and Mental deterioration: Postoperative inflammatory biomarkers such as soluble triggering receptor expressed on myeloid cells 2 (sTREM2) and CHI3L1 are neuroinflammatory biomarkers; a study found that high levels of sTREM2 and CHI3L1 indicated postoperative cognitive decline (Wang, Cao, et al., 2022; Zheng et al., 2023).