Proteomic profiling of plasma and serum in elderly patients with delirium.

The aim of this study was to compare plasma and serum protein profiles in elderly acute hip fracture patients with and without delirium. The spectra from surface-enhanced laser desorption ionization (SELDI) using time-of-flight (TOF) mass spectrometry of 16 patients without and 16 patients with delirium (two groups of eight and eight) scored using the Confusion Assessment Method were compared. The most discriminating peak of 15.9 kDa in plasma in a testing group of eight patients with delirium to eight patients without delirium was confirmed in an independent validation group. Taking both groups together, three discriminating peaks of 7.97, 15.9, and 16.0 kDa were found in delirious patients. These peaks presumably correspond to hemoglobin-beta, its doubly charged ion, and its glycosylated form.