Chang CY, Chien YJ, Lin PC, et al. - Researchers investigated how non-thyroidal illness syndrome (NTIS) and hypothyroidism can impact all-cause death as well as major adverse cardiac events (MACE) in patients with ischemic heart disease (IHD). Eligible articles were identified from PubMed, EMBASE, Scopus, Web of Science, and Cochrane Library explored from inception through February 17, 2020. Eligibility criteria included studies with IHD patients, comparing all-cause death and MACE of NTIS and hypothyroidism vs those of euthyroidism, and affording adequate information for meta-analysis. Overall 23 studies were analyzed. Findings revealed a higher risk of all-cause mortality and MACE in correlation with IHD with concomitant NTIS or hypothyroidism. Subgroup analysis revealed a higher risk of all-cause death and MACE in relation to acute coronary syndrome (ACS) subpopulation with NTIS. A higher risk of all-cause mortality was noted in relation to ACS subpopulation with hypothyroidism.