A - 104 Cardiometabolic Multimorbidity Is Associated with Greater Amyloid Burden in Cognitively Stable Adults with Down Syndrome

Objective Nearly everyone (>90%) with Down Syndrome (DS) develops Alzheimer’s Disease (ad). Cardiometabolic conditions (CC) are known dementia risk-factors in the general population, and cardiometabolic multimorbidity (CM) increases MCI, dementia, and ad. CC are highly prevalent in DS and amyloid burden (AB) is associated with ad and elevated across lifespan in DS. However, there are no studies on the association between CM and AB in DS. Method We studied baseline data from 240 participants, 40–53 years (198 cognitively stable; 42 with MCI or dementia), from Alzheimer’s Biomarker Consortium-Down Syndrome (ABC-DS). Participants were grouped 0–1 or > 1 CC (hyperlipidemia, hypothyroidism, hypertension, cardiovascular conditions, stroke). Participants completed amyloid PET scan with [11C]-Pittsburgh compound B ([11C]-PiB) or [18F]-AV45 (florbetapir). Regional standard uptake value-ratios (SUVRs) were calculated relative to cerebellar cortex and transformed to Centiloid global AB scores for analysis. We tested association between CM and AB scores using hierarchical linear regression, including age and apolipoprotein E (ApoE) as covariates. Results The regression model revealed that CM was significantly associated with greater AB after accounting for age and ApoE [F (3,194) = 57.752, p < 0.001, ß = 0.228, 95% CI [0.007–0.449], p = 0.043]. Centiloid values were higher for two or more CC (Fig. 1). Conclusion Our results suggest that two or more CC is associated with greater AB in cognitively stable adults with DS. These findings help us understand the CM prodromal role in accelerating ad in DS and provide insights to preventative strategies. Future studies should explore how CM and related biomarkers, eg., chronic peripheral inflammation, influence ad in DS.