Blood Test May Help to Assess Memory Loss

Thrombogenic microvesicles are shed by activated platelets in the blood, and Mayo Clinic (Minnesota, USA) researchers report that they may be an indicator of the risk of developing white matter hyperintensities (WMH) – small areas of brain damage that have been linked to memory loss.  Kejal  Kantarci and colleagues analyzed 95 women, average age 53 years, who were a subset of those enrolled in the Mayo Clinic Kronos Early Estrogen Prevention Study, in which magnetic resonance imaging (MRI) was used to measure changes in WMH before randomization and at 18, 36, and 48 months afterward.  At the study’s start, the researchers measured conventional cardiovascular risk factors, carotid intima-media thickness, coronary arterial calcification, plasma lipids, markers of platelet activation, and numbers of thrombogenic microvesicles.  They correlated those with changes in WMH volume, adjusting for a number of factors.  On average across the subjects, the volume of WMH rose by 63 mm3 at 18 months, 122 mm3 at 36 months, and 155 mm3 at 48 months. Whereas only the 36- and 48-month levels were significantly different from baseline, these levels were significantly correlated with the numbers of platelet-derived and total thrombogenic microvesicles observed at baseline, and not with the other measured risk factors.  The study authors conclude that: “Associations of platelet-derived, thrombogenic microvesicles at baseline and increases in [white matter hyperintensities] suggest that in vivo platelet activation may contribute to a cascade of events leading to development of [white matter hyperintensities] in recently menopausal women.”