Brain diseases represent a significant global health burden. Traditional diagnostic tools, such as neuroimaging and cognitive tests, are often costly and time-consuming. Emerging biomarkers like the Placental Growth Factor (PlGF) may provide a faster, more cost-effective alternative for diagnosing brain diseases.
Eighteen studies involving 6,866 patients (54% female) were included, with most conducted in high-income countries. Study designs included cross-sectional (5), observational cohort (7), clinical trials (2), secondary analysis of cohorts (2), and longitudinal cohorts (1). Eleven studies found elevated PlGF levels associated with cognitive decline—four for vascular cognitive impairment, nine for Alzheimer’s disease, and one for frontotemporal dementia. One study focused on traumatic brain injury. Two studies reported diagnostic metrics, with AUC values for PlGF ranging from 0.66 (white matter hyperintensity) to 0.996 (frontotemporal dementia vs. control). Vascular cognitive impairment showed moderate diagnostic accuracy (AUC 0.74–0.89). Only one study reported sensitivity and specificity, with 100% sensitivity and 96% specificity for distinguishing frontotemporal dementia from controls. Additionally, one study reported an odds ratio of 8.31 [6.77–10.1] for the association between PlGF and vascular dementia.