IL6 and Alzheimer disease: Although a systematic review and meta-analysis of the existing literature on biomarkers of POD [e.g. (Lozano-Vicario et al., 2023)] would certainly benefit the field of POD research, we feel that such an endeavor is premature for many of the topics discussed here apart from IL-6 and AD biomarkers, for which there are several excellent meta-analyses available (Geng et al., 2024; Wang S. et al., 2022).