Life's Essential 8 and Poor Brain Health Outcomes in Middle-Aged Adults

Abstract

Background and objectives: Mounting evidence points to a strong connection between cardiovascular risk during middle age and brain health later in life. The American Heart Association's Life's Essential 8 (LE8) constitutes a research and public health construct capturing key determinants of cardiovascular health. However, the overall effect of the LE8 on global, clinically relevant metrics of brain health is still unknown. We tested the hypothesis that worse LE8 profiles are associated with higher composite risk of the most important clinical endpoints related to poor brain health.

Methods: We conducted a two-stage (discovery and replication) prospective study using data from the UK Biobank (UKB) and All of Us (AoU), 2 large population studies in the United Kingdom and the United States, respectively. The primary exposure was the LE8 score, a validated tool that captures 8 modifiable cardiovascular risk factors (blood pressure, glucose, cholesterol, body mass index, smoking, physical activity, diet, and sleep duration), organized in 3 categories (optimal, intermediate, and poor). The primary outcome was a composite of stroke, dementia, or late-life depression. We evaluated associations using multivariable Cox proportional hazard models.

Results: The discovery stage included 316,127 UKB participants (mean age 56, 52% female). Over a mean (SD) follow-up time of 4.9 (0.4) years, the unadjusted risk of the composite outcome was 0.7% (95% CI 0.61-0.74), 1.2% (95% CI 1.11-1.22), and 1.8% (95% CI 1.70-1.91) in participants with optimal, intermediate, and poor cardiovascular health, respectively (p < 0.001). This association remained significant in multivariable Cox models (intermediate vs optimal cardiovascular health hazard ratio [HR], 1.37; 95% CI 1.24-1.52, and poor vs optimal cardiovascular health HR, 2.11; 95% CI 1.88-2.36, p trend <0.001). The replication stage included 68,407 AoU participants (mean age 56, 60% female). Over a mean (SD) follow-up time of 2.9 (1.41) years, the unadjusted risk of the composite outcome was 2.8% (95% CI 2.49-3.05), 6% (95% CI 5.76-6.22), and 9.7% (95% CI 9.24-10.24) in participants with optimal, intermediate, and poor cardiovascular health, respectively (p < 0.001). This association remained significant in multivariable Cox models (intermediate vs optimal cardiovascular health, HR 1.35; 95% CI 1.21-1.51, and poor vs optimal cardiovascular health, HR 1.94; 95% CI 1.72-2.18; p trend <0.001).

Discussion: Among middle-aged adults enrolled in 2 large population studies, poor cardiovascular health profiles were associated with two-fold higher risk of developing a composite outcome that captures the most important diseases related to poor brain health. Because the evaluated risk factors are all modifiable, our findings highlight the potential brain health benefits of using the Life's Essential 8 to guide cardiovascular health optimization.