Cardiovascular Health and Biomarkers of Neurodegenerative Disease in Older Adults.

Importance: Cardiovascular health (CVH), defined by the American Heart Association as Life's Simple 7 to promote a healthy lifestyle and manage vascular risk factors, has been associated with a low risk of Alzheimer disease and less vascular dementia. However, the association between CVH and biomarkers of neurodegeneration remains less understood.

Objective: To investigate the association of CVH with serum biomarkers of neurodegeneration, including neurofilament light chain (NfL) and total tau (t-tau).

Design, setting, and participants: This cohort study was conducted within the biracial, population-based Chicago Health and Aging Project (CHAP) of adults aged 65 years or older between 1993 and 2012. Participants who had measured serum NfL and t-tau levels and data on all components of the CVH score were included. The statistical analysis was conducted from April 10 to September 26, 2024.

Exposure: The CVH score includes 7 components: a healthy diet; regular exercise; normal body mass index; nonsmoking status; and the absence of dyslipidemia, diabetes, and hypertension. The scores were divided into 3 groups from lowest to highest CVH (0-6 points, 7-9 points, and 10-14 points).

Main outcomes and measures: The main outcome was the association of CVH score with serum biomarkers of NfL and t-tau as measured using linear regression and mixed-effects models.

Results: A total of 1018 CHAP participants were included in the analysis (mean [SD] age, 73.1 [6.1] years; 625 female [61.4%]; 610 Black or African American [59.9%] and 408 White [40.1%]). Participants with a high CVH score (ie, 10-14 points) were predominantly White (151 [64.3%]) and had a higher education (mean [SD], 13.6 [3.7] years). Compared with participants with low CVH scores (ie, 0-6 points), those with CVH scores of 10 to 14 points had significantly lower serum levels of NfL (relative difference, -18.9%; β = -0.091; SE, 0.025). A higher CVH score was associated with a slower annual increase in NfL levels as participants aged (relative difference in rate, -1.7%; β = -0.008; SE, 0.004). Cardiovascular health was not associated with serum levels of t-tau.

Conclusions and relevance: These findings suggest that promoting CVH in older adults may help alleviate the burden of neurodegenerative diseases, particularly among Black adults, who are known to experience a higher prevalence of cardiovascular disease.