GDF15 and Alzheimer disease: From a recent prospective study (McGrath et al., 2020), higher circulating GDF-15 was associated with an increased risk of incident AD (hazard ratio = 1.37; p = 0.03), but it should be noted that prior smaller cohorts were prone to confounding bias (i.e., healthy conditions and socioeconomic status), and validation of their findings in a larger sample size is required.