Utilidad de los biomarcadores en el diagnóstico de la enfermedad cerebrovascular silente

Résumé

ABSTRACT: Nowadays cerebrovascular diseases have a major social impact; they are a commonly associated with increased rates of hospitalization, morbidity and mortality. Furthermore, it is expected that ageing will increase the incidence of cerebrovascular diseases and their associated healthcare costs. Cerebral infarcts occurring without stroke-like symptoms are known as silent or covert cerebral infarcts; they are five times more common than symptomatic stroke. Most of them are lacunar infarcts and they appear associated with other imaging markers of cerebral small vessel disease, as white matter hyperintensities, microbleeds or dilated perivascular spaces. Research on cerebral small vessel disease pre-clinical or pre-symptomatic stages may potentially improve the knowledge of the leading and involved disease pathways, and the development of prevention approaches aimed to reduce their incidence and associated complications (such as stroke and dementia). In this Thesis, we have performed a bibliographic literature review, and found that the number of studies regarding biomarker usefulness in the early detection of small vessel disease by identification of silent or subclinical cerebral lesions have increased for the last years. However, the use of biomarkers with diagnostic purposes to detect silent brain lesions has not been already established, so clinical their usefulness is still not justified. Previous studies limitations are heterogeneity regarding cerebral small vessel disease lesions definitions, the lack of replication in independent cohorts and the use of individual candidate biomarkers. Also longitudinal studies are needed to evaluate lesions progression and biomarkers associations. In this Thesis we also included biomarker study results, based on a hypertensive stroke and dementia-free population, 50-70 years old. This is a suitable population for the study of the onset of the disease, since hypertension is an established vascular risk factor. Magnetic resonance imaging-defined lesions where analyzed individually, and then combined in a previously described cerebral small vessel disease score being the latter a more physiologic condition. Statistic criteria were applied to evaluate the usefulness of the clinical models including the selected biomarkers, in the clinical practice. Small vessel disease biomarkers study can improve diagnosis of silent brain cerebrovascular lesions and also provide information regarding preclinical stage leading pathways. They can be useful as therapeutic and disease progression monitoring targets.