Vascular risk levels affect the predictive value of platelet reactivity for the occurrence of MACE in patients on clopidogrel. Systematic review and meta-analysis of individual patient data.

Prior studies have shown an association between high on-clopidogrel platelet reactivity (PR) and the risk of major adverse cardiovascular events (MACE). However, large intervention trials on PR-tailored treatments have been neutral. The role and usefulness of PR with regard to levels of cardiovascular risk are unclear. We undertook a systematic review and meta-analysis of individual patient data on MACE outcomes (acute coronary syndromes (ACS), ischaemic strokes, and vascular deaths) in relation to PR and its interaction with cardiovascular risk levels. PR was determined using ADP-induced light transmission aggregometry with a primary concentration of 20 µM ADP. Thirteen prospective studies totaled 6,478 clopidogrel-treated patients who experienced 421 MACE (6.5 %) during a median follow-up of 12 months. The strength of the association between the risk of MACE and PR increased significantly (p=0.04) with the number of risk factors present (age> 75 years, ACS at inclusion, diabetes, and hypertension). No association was detected in patients with no risk factor (p=0.48). In patients presenting one risk factor, only high-PR was associated with an increased risk of MACE (HR 3.2, p=0.001). In patients presenting ≥ 2 risk factors, the increase of risk started from medium-PR (medium-PR: HR=2.9, p=0.0004; high-PR: HR=3.7, p=0.0003). PR allowed the reclassification of 44 % of the total population to a different risk level for the outcome of MACE, mostly in intermediate or high risk patients. In conclusion, the magnitude of the association between PR and MACE risk is strongly dependent on the level of cardiovascular risk faced by patients on clopidogrel

Varia 2018

Communiquer, Revue de communication sociale et publique contribue à une meilleure compréhension des phénomènes de communication humains. Cette thématique est abordée dans son ensemble, qu'elle soit organisationnelle, interculturelle et internationale, interpersonnelle et de groupe, marketing et publicitaire, politique ou qu'elle touche à la santé, l'environnement, les technologies, la communication scientifique, les relations publiques, sans que ces indications ne soient exhaustives

Vascular risk levels affect the predictive value of platelet reactivity for the occurrence of MACE in patients on clopidogrel. Systematic review and meta-analysis of individual patient data

Prior studies have shown an association between high on-clopidogrel platelet reactivity (PR) and the risk of major adverse cardiovascular events (MACE). However, large intervention trials on PR-tailored treatments have been neutral. The role and usefulness of PR with regard to levels of cardiovascular risk are unclear. We undertook a systematic review and meta-analysis of individual patient data on MACE outcomes (acute coronary syndromes (ACS), ischaemic strokes, and vascular deaths) in relation to PR and its interaction with cardiovascular risk levels. PR was determined using ADP-induced light transmission aggregometry with a primary concentration of 20 µM ADP. Thirteen prospective studies totaled 6,478 clopidogrel-treated patients who experienced 421 MACE (6.5 %) during a median follow-up of 12 months. The strength of the association between the risk of MACE and PR increased significantly (p=0.04) with the number of risk factors present (age> 75 years, ACS at inclusion, diabetes, and hypertension). No association was detected in patients with no risk factor (p=0.48). In patients presenting one risk factor, only high-PR was associated with an increased risk of MACE (HR 3.2, p=0.001). In patients presenting ≥ 2 risk factors, the increase of risk started from medium-PR (medium-PR: HR=2.9, p=0.0004; high-PR: HR=3.7, p=0.0003). PR allowed the reclassification of 44 % of the total population to a different risk level for the outcome of MACE, mostly in intermediate or high risk patients. In conclusion, the magnitude of the association between PR and MACE risk is strongly dependent on the level of cardiovascular risk faced by patients on clopidogrel

The early development of inorganic chlathrates

In this chapter the authors relate the discovery of the first inorganic clathrates, Na8Si46 and NaxSi136 (3 ≤ x ≤ 11), whose cage-like structures were determined by comparison with those of the two most classical gas and liquid clathrate hydrates. The main characteristics of clathrate compounds are recalled and a brief review of clathrate hydrates is given. The different polyhedral cages and their arrangements in the so-called type I structure (Na8Si46) and type II structure (NaxSi136) are described in details. The synthesis, composition and structure of other inorganic clathrates of silicon, germanium and tin with potassium, rubidium and cesium as guest atoms are reported. The crystal structure (type I or type II) and corresponding composition is closely related to the size of the guest alkali atoms. The formation of the characteristic polyhedral cages with a majority of pentagonal faces is discussed, and results from the arrangement of all the tetrahedrons in eclipsed position. The relation between clathrate structures and those of clathrasils (silica-based clathrates), Frank-Kasper alloys and fullerene forms of carbon is also discussed. The first measurements of the physical properties of inorganic clathrates are reviewed, including electrical conductivity, thermal properties, high pressure behavior, NMR and ESR investigations. The ability for the silicon, germanium and tin host lattices to form non-stoichiometric and mixed frameworks with elements of neighboring groups is briefly described, giving rise to a large variety of new inorganic clathrates with ionic guest-host interactions and semiconducting properties