Estudio de la enfermedad de Alzheimer en el síndrome de Down

Resumen

Down syndrome (DS) is the leading genetic cause of intellectual disability affecting 1/700-800 live births. The advances in the last decades have increased their life expectancy and, as a consequence, the incidence of health related problems such as neurodegenerative disorders. Alzheimer's disease is almost universal in adults with DS. To describe and to compare the sociodemographic and clinical characteristics of a Spanish cohort of adults with DS with and without dementia due to AD. To estimate the prevalence of AD in a cohort of adults with DS and to identify factors associated with it. To describe the clinical course of adults with AD. A cross-sectional observational study of a retrospective cohort of people with DS chosen by means of a consecutive sample of people treated at the Adult Care Unit with DS from 2005 to December 2016, where a case-control study of patients with and without AD has been performed. Sub-study of longitudinal observational cohorts of the 68 patients diagnosed with AD. A total of 400 adults with DS were analyzed. Of these, 68 patients, 17% (CI: 13.3%-20.7%) were diagnosed with AD (mean age 55±5 years), increasing the prevalence with age and without diagnoses under 40 years. No differences were found in gender prevalence. Institutionalization was more frequent in adults with AD. Endocrine-metabolic pathology was the most prevalent in adults with AD. Hypothyroidism (88,2%) and age-related pathologies such as cataracts (57.4%), osteoarthritis (11%) and hallux valgus (11%) were more frequent in this group than those without AD. Among neuropsychiatric comorbidities, late-onset epilepsy (36.5%) more frequent in more advanced stages of the disease, depression (51.5%) and agitation-aggressiveness (32.4%) were more prevalent among adults with AD compared to those without this pathology. CAT alterations appeared in relation to AD before age 40, even in adults without AD. Generalized cortical atrophy and widening of grooves with dilation of ventricles as a compensatory mechanism were significantly more frequent in adults with AD. The form of presentation of AD in the DS is atypical with behavioral alterations and executive dysfunctions in early stages to later appear alteration of memory and language and apraxias mainly with progressive increase of the dependency in the more advanced phases. AD is very prevalent in adults with Down's Syndrome, appearing in 17% of the cohort studied. Age, late epileptic seizures, and depression are significantly and independently associated with the onset of AD. The probability of developing AD in those older than 50 years with atrophy in the CAT is 92%. Behavioral symptoms and executive deficits are the most frequent at the onset of the disease, with recent memory alteration and apraxia with the evolution of the same and greater dependence and seizures in advanced stages.