Platelet reactivity in frail older women: integrating phenomic and proteomic analysis

Abstract The impact of altered platelet responsiveness associated with disease or ageing is poorly understood. In this study, we sought to determine whether frailty in old age, which is itself associated with an increased risk of cardiovascular disease, is associated with altered platelet function, which may underpin such conditions that impact poorly on prognosis. Platelet responses (P-Selectin exposure and fibrinogen binding) to platelet activators (ADP, CRP, and TRAP-6) were measured in platelet-rich plasma (PRP) by flow cytometry. Platelet-free plasma (PFP) was used for proteomic analyses and the study of extracellular vesicles (EVs). In the studied population (50 women), significant differences were observed between non-frail and frail participants, with frail individuals showing increased platelet phosphatidylserine exposure, intracellular calcium mobilization, and fibrinogen binding. Higher levels of EVs and alterations in the plasma proteome of frail people were observed. A new cut-off score for FTS-5 could represent a novel tool for evaluating the behavior of platelets in older people, who present some alterations in the platelet reactivity profile and other platelet characteristics, which could constitute a cardiovascular risk factor.