APOE and Alzheimer disease: AD subjects had average atrophy rates of 14 mL/year for the whole brain and 0.2 mL/year for HP. MCI (APOE negative) subjects had average rates of 10 mL/year for the whole brain and 0.1 mL/year for the HP.NC subjects (APOE negative) had average atrophy rates of 6 mL/year for the whole brain and 0.06 mL/year for the HP, and greater age at baseline was associated with significantly increased HP atrophy rate (0.03 mL/year for a 10-year increase).In NC, higher HP atrophy rates with age were observed and a reduction in HP atrophy rate with age was observed for AD.