Stroke Burden Attributable to Risk Factors in the Americas, 1990-2021: A Temporal Trends Analysis from the GBD 2021

BackgroundStroke remains a major public health concern with marked disparities across populations, particularly in the Americas. Despite documented declines in overall burden, limited data exist on how modifiable risk factors contribute to contemporary stroke trends across the continent. MethodsUsing data from the Global Burden of Disease 2021 study, we analyzed age- standardized mortality rates and age-standardized disability-adjusted life-years (DALYs) rates from stroke attributable to 23 modifiable risk factors across 39 countries and territories in the Americas. Estimates were stratified by age, sex, stroke subtype, and Socio-Demographic Index (SDI). Temporal trends from 1990 to 2021 were assessed using the average annual percent change (AAPC), which was estimated applying Joinpoint regression analysis. ResultsIn 2021, 78% of stroke deaths and 77% of stroke DALYs were attributable to modifiable risk factors in the Americas. High systolic blood pressure was the leading risk factor (20.87 deaths [95% uncertainty interval: 15.17-25.8] and 453.30 DALYs [333.16-556.41] per 100,000), contributing over half of stroke burden. From 1990-2021, the largest reductions occurred in household air pollution (deaths AAPC -5.09% [-5.17--5.02]; DALYs AAPC -4.92% [-4.98--4.86]) and secondhand smoke (deaths AAPC -3.45% [-3.49--3.41]; DALYs AAPC -3.37% [-3.41--3.33]). In contrast, several risk factors showed minimal progress: high body-mass index (deaths AAPC -0.54% [-0.59--0.49]; DALYs AAPC -0.42% [-0.46--0.37]) and high fasting glucose (deaths AAPC -1.10% [-1.14--1.06]; DALYs AAPC -0.99% [-1.05--0.93]). High temperature demonstrated increases, with AAPCs exceeding +3.5% in select countries. High systolic blood pressure declined moderately (deaths AAPC -1.89% [-1.93--1.85]; DALYs AAPC -1.84% [-1.89--1.80]), with stroke burden remaining disproportionately higher in low-SDI countries. ConclusionAlthough encouraging declines in stroke burden attributable to risk factors have been observed over three decades, substantial variation persists by geography and SDI. High systolic blood pressure remains the leading modifiable risk factor. Minimal progress in obesity and metabolic factors highlights the need for equity-focused strategies to address persistent and emerging stroke risks across the Americas.