Abstracts
Résumé
Le syndrome métabolique, asymptomatique, résulte de la prévalence élevée de l’obésité. Malgré l’intérêt scientifique croissant suscité par ce syndrome, notamment en raison du problème majeur de santé publique qu’il soulève, lié au vieillissement de la population et à l’évolution des modes de vie, ses mécanismes physiopathologiques ne sont pas élucidés, et sa définition comme ses critères diagnostiques encore non harmonisés. Malgré cette coexistence de plusieurs définitions qui compliquent son diagnostic, il est caractérisé par la conjonction de troubles, souvent modérés, d’origine glucidique, lipidique ou vasculaire, associés à une surcharge pondérale, qui vont agir en synergie, provoquer un diabète de type 2 et prédisposer à l’athérosclérose et à ses événements cliniques. La prévalence du syndrome métabolique, élevée quel que soit l’âge, est en forte progression chez les jeunes. Au-delà des interventions hygiénodiététiques, la plupart des traitements actuels sont focalisés sur un seul facteur de risque, et ne satisfont pas réellement le besoin médical : certaines classes d’antidiabétiques, d’hypolipémiants ou d’antihypertenseurs ont prouvé leur efficacité en prévention secondaire, contre la survenue d’événements cardiovasculaires, mais dans leurs indications respectives, et non spécifiquement chez les patients présentant un syndrome métabolique. Cependant, pour que le syndrome métabolique puisse être une indication thérapeutique spécifique, il faudrait identifier ses mécanismes physiopathologiques, harmoniser sa définition, démontrer l’efficacité clinique de certaines molécules et, probablement, développer de nouvelles entités dotées d’un mécanisme d’action multimodal. Quelques nouvelles approches sont évoquées, qui pourraient constituer une avancée décisive parallèlement à certains résultats positifs obtenus dans les études Field et Proactive relatives à l’utilisation de modulateurs PPAR (récepteurs activés par les proliférateurs de peroxisomes).
Summary
Metabolic syndrome is asymptomatic and results from the increasing prevalence of obesity. Although several definitions exist and complicate its diagnosis, metabolic syndrome is characterized by the clustering of moderate troubles of glucose, lipid metabolism, body weight, hypertension and vascular inflammation ; the synergy between 3 of them triggers type 2 diabetes, atherosclerosis and associated clinical events. Whatever the age but particularly in adolescence, the prevalence of metabolic syndrome is high ; beyond lifestyle interventions, the available treatments address essentially a single risk factor and an unmet medical need persists. The reduction of cardiovascular events in secondary prevention has been demonstrated for some antidiabetic, hypolipidemic and antihypertensive agents but any difference in efficacy between populations with and without metabolic syndrome has yet to be established. The approval of metabolic syndrome as a specific therapeutic target would need the characterization of its pathogenic mechanism, a clearer guidance for definition and diagnosis, and the clinical proof of concept of a novel molecule displaying multifactorial impacts. Some new mechanistic approaches are discussed and may represent a breakthrough particularly if positive results of Field and Proactive clinical studies related to PPARs are disclosed soon.
Appendices
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