Kamintsky L, Beyea SD, Fisk JD, et al. - In adult patients with systemic lupus erythematosus (SLE), the relationship between blood-brain barrier (BBB) integrity, brain volume, and cognitive dysfunction was tested. Researchers included 65 ambulatory patients with SLE and 9 healthy controls who had undergone dynamic contrast-enhanced MRI scanning for quantitative assessment of BBB permeability. They assessed global cognitive function by screening tasks falling into five broad cognitive domains; this was compared between patients with normal vs extensive BBB leakage. Compared with controls, patients with SLE had significantly greater levels of BBB leakage. Extensive BBB leakage (affecting over >9% of brain volume) was found only in patients with SLE, who also had smaller right and left cerebral grey matter volumes vs controls. Extensive BBB leakage was correlated with lower global cognitive scores, and with impairment on one or more cognitive tasks. Future trials are required to evaluate the mechanisms underlying BBB-mediated cognitive impairment, confirm the diagnostic utility of BBB imaging, and ascertain the potential of targeting the BBB as a therapeutic strategy in patients with SLE.