A study published in Brain has found correlations between serum and cerebrospinal fluid levels of insulin-like growth factor binding protein 2 (IGFBP2) and various measures of Alzheimer disease (AD) pathology. In a cohort of 241 individuals who were dementia-free, elevated plasma IGFBP2 was associated with an increased rate of conversion to AD. Insulin–IGF signalling has an important role in hippocampal function; thus, the findings could provide clues to the selective vulnerability of this region in AD.