HIGH PREVALENCE OF VASCULAR AND METABOLIC RISK FACTORS AMONG DOWN SYNDROME PATIENTS WITH ALZHEIMER’S DISEASE: A SURVEY REPORT OF THE NATIONAL DOWN SYNDROME REGISTRY (DS-CONNECT)

Abstract

Down syndrome (DS) patients have approximately five times greater risk of developing Alzheimer's disease (AD) compared to the general population, partially due to the presence of the amyloid precursor protein gene on chromosome 21. By age 40, nearly all individuals with DS have significant levels of the characteristic beta-amyloid plaques, yet not all of these individuals demonstrate cognitive decline. Given the high prevalence of AD within the DS population, it may prove that studying shared incidences of the two diseases will reveal specific risk factors for AD. We performed a preliminary study to investigate the prevalence of lifestyle-related health factors, such as type 2 diabetes, hypothyroidism, and lipid profile surveillance, among the DS population and their potential associations with AD. The survey analysis was performed using the de-identified national Down Syndrome Registry and aggregate data within the NIH database DS-Connect, the first web-based, voluntary DS registry and data resource. We identified 13 individuals with DS and AD. All individuals had filled out surveys, which included the diagnoses of disease variables and data on lifestyle risk factors. We identified 13 individuals with DS aged ≥ 30 who were concurrently diagnosed with AD. The mean age was approximately 45.8 years. The prevalences of hypothyroidism (58.3% vs. 48.5%) and thyroid dysfunction (76.9% vs. 55.7%) were higher in this population compared to DS patients without AD. DS patients with diabetes also saw a greater incidence of AD compared to DS patients without diabetes (33.3% vs. 14.8%). Additionally, DS patients who monitored their cholesterol on a yearly basis saw a decreased prevalence of AD (9.0% vs. 14.8%). Preliminary data from the Down Syndrome Registry shows that individuals with DS and AD have a higher prevalence of metabolic risk factors. Since these risk factors are modifiable, and their aggressive management and reversal have shown to reduce the pathophysiological markers of AD in non-DS populations, future studies are needed to investigate the association between metabolic and vascular risk factors and AD among the DS population, and explore mechanisms of prevention of cognitive impairment by management of these factors.