Vascular risk factors play a significant role in the pathogenesis and progression of AD. MPV is an index of platelet activation and may be a potential marker of inflammation to demonstrate the vascular damage in AD. The aim of the present study is to assess whether platelet volume would be useful in predicting vascular damage in AD. A total of 126 patients with AD (male/female: 44/82, mean age 76.2 +/- 6.8 years) and 286 patients as controls with normal cognitive function (male/female: 123/163, mean age 75.2 +/- 6.3 years) were enrolled in this cross-sectional study. MPV values were determined for all study participants. Mini-Mental State Examination (MMSE) and clock drawing tests (CDT) were performed for cognitive assessment, DSM-IV and NINCDS-ADRDA criteria were used for diagnosis of AD. The mean MPV values were significantly higher in AD group (8.46 +/- 1.15 vs. 8.17 +/- 0.90; p = 0.011). In this study, significantly higher MPV values in patients with AD have been detected. Since increased MPV levels are usually considered as a vascular risk factor, the results of this study suggested the role of platelet activation in the vascular pathogenetic basis of AD. (C) 2011 Elsevier Ireland Ltd. All rights reserved.