Stroke Burden Attributable to Risk Factors in the Americas, 1990 to 2021: A Temporal Trends Analysis From the GBD Study 2021.

BACKGROUND

Stroke burden varies across the Americas, yet data on modifiable risk factor contributions remain limited.

METHODS

Using GBD (Global Burden of Disease) study 2021 data, we analyzed stroke mortality and disability-adjusted life-year (DALY) rates attributable to 23 modifiable risk factors across 39 countries and territories in the Americas. Age-standardized rates were compared by sex, stroke subtype, region, and Socio-Demographic Index; age-specific estimates used 5-year groups (25-95+ years). Trends were assessed using average annual percentage change (AAPC) from Joinpoint regression.

RESULTS

In 2021, 78.8% (95% uncertainty interval, 70.1%-85.9%) of stroke deaths and 76.9% (68.2%-83.6%) of DALYs were attributable to the 23 risk factors combined. High systolic blood pressure was the leading contributor, accounting for 20.87 attributable deaths (95% uncertainty interval, 15.17-25.80) and 453.30 DALYs (333.16-556.41) per 100 000, representing 54.8% of deaths and 52.2% of DALYs. From 1990 to 2021, the largest reductions occurred for household air pollution from solid fuels (deaths AAPC, -5.09% [95% CI, -5.17 to -5.02]; DALYs AAPC, -4.92% [-4.98 to -4.86]) and secondhand smoke (deaths AAPC, -3.45% [-3.49 to -3.41]). Reductions were minimal for high body mass index (deaths AAPC, -0.54% [-0.59 to -0.49]; DALYs AAPC, -0.42% [-0.46 to -0.37]), high fasting plasma glucose (deaths AAPC, -1.10% [-1.14 to -1.06]), and dietary risks; high body mass index burden increased in the Caribbean, notably in Haiti and the Dominican Republic. Stroke deaths attributable to high temperature increased >3.5% annually (AAPC) in Panama, Jamaica, and the Dominican Republic. High systolic blood pressure burden remained highly unequal, with age-standardized death rates of 10.42 per 100 000 in high-Socio-Demographic Index versus 109.33 in low-Socio-Demographic Index countries.

CONCLUSIONS

Stroke burden attributable to modifiable risk factors declined overall, but marked disparities persisted. High systolic blood pressure remained dominant, whereas stalled or increasing burden from obesity, metabolic, and dietary risks highlights the need for equity-focused prevention across the Americas.