The impact of congenital heart disease on the timing of Alzheimer's disease in Down syndrome

INTRODUCTION: The incidence of Alzheimer's disease (AD) in Down syndrome (DS) exceeds 90%. Approximately 50% of people with DS have congenital heart disease (CHD). Having CHD increases risk for early-onset AD in populations without DS, but it is unclear if CHD influences AD in DS. METHODS: Data from the Alzheimer Biomarker Consortium-Down Syndrome (ABC-DS) were used. Participants with CHD (n = 82, mean age = 39.9 ± 8.5 years, 97.6% White race) were age- and sex-matched to participants without CHD (n = 82, mean age = 40.5 ± 8.1 years, 98.8% White race). Cognitive assessments and Centiloid load (CL) (positron emission tomography) were compared by CHD status. RESULTS: People with CHD scored lower for visuospatial ability (β = −3.515, p = 0.022) but had higher CL (29.8 ± 12.8 vs. 39.8 ± 12.8, β = 8.00, p = 0.036) and were projected to hit Aβ positivity at a younger age (37.6 and 42.1 years). DISCUSSION: Presence of CHD may influence AD progression in DS. Highlights: In adults with Down syndrome (DS), those with congenital heart disease (CHD) had higher amyloid beta and reached the threshold for an amyloid positivity at a younger age than those without CHD No differences in cognition were seen in the age- and sex-matched sample based on CHD status; however, the average age of the sample may be too young to see cognitive changes CHDs may influence the timing of Alzheimer's disease (AD) in adults with DS.