La enfermedad de Alzheimer en fase prodromicaestudio transversal e identificacion de marcadores de progresion a demencia en una serie prospectiva en pacientes con deterioro cognitivo ligero

Abstract

Title: Prodromal Alzheimer's disease: Cross-sectional study and identificatión of markers of progression to dementia in a prospective series of patients with mild cognitive impairment. Alzheimer's disease (AD) represents the most common type of dementia in our society. There are neither diagnòstic biomarkers ñor an effective treatment. There is evidence that the degenerative disease process may begin many years before prior to the actual cl i ni cal diagnosis. As a result, by the time a diagnosis is established, many cerebral regions have already suffered extensive irreversible damage. Thus, before dementia occurs there is probably an intermedíate stage of impairment which is not normal for age but not sufficiently severe to consti tute the diagnosis of dementia of AD type. This transitional stage has been called mil d cognitive impairment (mci) and may well represent the prodromal stage of AD. The main goal of this study is to identify predictive markers to accurately distinguish those patients with mci who will convert to dementia of AD type from the non-converters. we have designed a prospective study in a cohort of 300 individuals (103 mci, 63 mild to modérate AD, 80 subjective memory complains and 54 non-demented controls). We studied the following potential disease markers: 1) Neuropsychological test performance; 2) genètic risk factors (apoe, alpha-2-macroglobulin and interleukin 1a genotypes); 3) volumètric measurements in magnètic resonance; and 4) cerebral glucose metabolism in PET studies. Most mci patients had executive dysfunction pure amnestic mci was rare. The index of progressi on was 17%, most to AD. Measures of general cognition (MMSE, ticmb), memory (fcsrt) and executive function (TMT-b, semàntic fluency) as well as parietal, temporal and cingular hipomeabolism were significant predictors of progressi on. In addition, this study provided very valuable information on the natural course of mci. From a practical perspective, identification of earliest markers of progressi on will allow interventions at an early point in the disease process when ethiopatogenic therapi es might be effective.