Global cerebrovascular burden and long-term clinical outcomes in Asian elderly across the spectrum of cognitive impairment

ABSTRACTBackground/Aim:To investigate the predictive ability of the previously established global cerebrovascular disease (CeVD) burden scale on long-term clinical outcomes in a longitudinal study of Asian elderly participants across the spectrum of cognitive impairment. METHODS: A case-control study was conducted over a 2-year period involving participants with no cognitive impairment, cognitive impairment-no dementia (CIND), and Alzheimer's disease (AD). Annually, cognitive function was assessed with a comprehensive neuropsychological battery and the clinical dementia rating (CDR) scale was used to stage disease severity. RESULTS: Of 314 participants, 102 had none/very mild CeVD, 31 mild CeVD, 94 moderate CeVD, and 87 severe CeVD at baseline. There was a 1.14 and 1.42 units decline per year on global cognitive z-scores in moderate and severe CeVD groups, respectively, compared to none/very mild CeVD. Moderate-severe CeVD predicted significant functional deterioration at year 2 (HR = 2.0, 95% CI = 1.2-3.4), and conversion to AD (HR = 6.3, 95% CI = 1.7-22.5), independent of medial temporal atrophy. CONCLUSION: The global CeVD burden scale predicts poor long-term clinical outcome independent of neurodegenerative markers. Furthermore, CeVD severity affects the rate of cognitive and functional deterioration. Hence, cerebrovascular burden, which is potentially preventable, is a strong prognostic indicator, both at preclinical and clinical stages of AD, independent of neurodegenerative processes.