Rate of progression in Alzheimer's disease correlates with coated-platelet levels--a longitudinal study.
Coated-platelets represent a subset of platelets produced by activation with both collagen and thrombin that retain full-length amyloid precursor protein on their surface. In our initial cross-sectional study, coated-platelet levels correlated inversely with disease severity in Alzheimer's disease (AD). Higher levels were observed in the early stage compared with the advanced stage of the disease. In this longitudinal study, we investigated for the first time the relationship between initial coated-platelet levels and disease progression in individuals with AD. Coated-platelet levels were assayed in 25 patients with AD who where then clinically monitored for 2 years. A significant linear correlation (r = 0.47, P = 0.017) was detected between the initial coated-platelet levels and disease progression measured in the Mini-Mental State Examination score. The most severe decline was noted in individuals with the highest initial coated-platelet production. These findings support our previous observations from cross-sectional studies and suggest the need for additional study of coated-platelets as a link to the sequence of events leading to the development of AD.
Prodan
Calin I
CI
Neurology Service, Veterans Administration Medical Center, Oklahoma City, OK 73104, USA. calin-prodan@ouhsc.edu
Ross
Elliott D
ED
Vincent
Andrea S
AS
Dale
George L
GL
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism* / Q000503:physiopathology*; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism; D001792:Blood Platelets / Q000378:metabolism*; D010054:Brief Psychiatric Rating Scale; D003430:Cross-Sectional Studies; D018450:Disease Progression; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D015539:Platelet Activation / Q000502:physiology*; D011446:Prospective Studies; D012720:Severity of Illness Index; D013499:Surface Properties
D016564:Amyloid beta-Protein Precursor