Prevalencia y determinantes de las lesiones vasculares cerebrales definidas por resonancia magnética y estudio de la función cognitiva en población adulta hipertensa y general

Abstract

Cerebrovascular disease (stroke) and dementia are first leading causes of death and disability in adults in developed countries. An important amount of public health budgets are spent in those diseases and their incidence is expected to grow with the aging population. Both diseases might have a preclinical stage, without overt symptoms or with mild symptoms. Studying these diseases in these preclinical stages might help to understand the disease pathophysiology and evolution and might enable the prevention of future stroke and progression to dementia. In this Thesis we describe the methodology of the ISSYS study (Investigating Silent Strokes in hYpertensives, a magnetic resonance imaging Study) and its main results. This study is a community-based study in hypertensive individuals, middle and older aged, and therefore at high risk of stroke and dementia. We studied the preclinical stages of stroke and dementia and their determinants in these participants. We used brain Magnetic Resonance Imaging to identify subclinical vascular lesions and cognitive evaluation to diagnose Mild Cognitive Impairment (MCI). Also we studied prevalence and determinants (vascular risk factores and cognitive function) of small cortical infarcts in a non-demented, aged, general community-based study (Rotterdam Study). We showed that prevalence of silent brain infarcts is 10% in hypertensive individuals of ISSYS study (n=1037) and they are independently associated to male sex, higher cardiovascular risk score (assessed by REGICOR, Framingham calibrated equation for Spanish individuals) and other hypertension target organ damage (microalbuminuria). Enlarged Perivascular Spaces are ubiquitous in hypertensive individuals and are associated with ageing and other small vessel disease markers. 17. 5% of the ISSYS participants had a score in a dementia screening scale (DRS-2) lower than expected by age and education years. MCI prevalence is 8. 9% and is associated with lower education, sleep arterial stiffness measured by ambulatory pulse pressure and extensive deep white matter hyperintensities. Small cortical infarcts ( 15mm) prevalence is low (1. 1% in the general aging population, n=4905). We find them mostly in anterior and posterior external borderzone areas of big brain arteries. They are associated with vascular risk factors (aging, male sex and smoking) and worse cognitive function (worse delayed memory and executive function) than participants without any infarct in the general population. ISSYS study will allow the study of the natural history of stroke and cognitive impairment subclinical phases and will permit the study of prevention therapies for stroke and dementia in hypertensive individuals.

Date of Award	23 Jun 2015
Original language	Spanish
Supervisor	Juan Bernardo Montaner Villalonga (Director) & Maria Pilar Delgado Martinez (Director)