Lower levels of Chromogranin-A (CgA) were associated with higher whole brain atrophy (0.008) and ventricular expansion (0.009) after adjusting for baseline volumes and t-tau and predicts higher whole brain atrophy (P=0.009) after additionally adjusting for p-tau, age, ApoE status and sex. The gene discussed is APOE; the disease is Brain atrophy.