Bayesian Modeling to Project the National and Regional Burden of Rheumatic Heart Disease in Brazil Till 2050

Background: Rheumatic heart disease (RHD) remains a significant public health concern in middle- to low-income countries. Despite advancements in healthcare access and public health measures in Brazil, future projections of RHD burden are essential to guide policy-making. Thus, we projected the national and regional burden of RHD in Brazil through 2050. Methods: Annual prevalence counts and disability-adjusted life years (DALYs) for RHD from 2000 to 2021 were extracted from the 2021 Global Burden of Disease (GBD) dataset for 10-year age brackets (5-74 years). Age-standardized prevalence (asPR) and DALYs rates (asDALYs) per 100,000 were calculated nationally and regionally. Bayesian age-period-cohort models were used to project trends through 2050, with results reported as medians (25th, 75th percentiles) and estimated annual percentage changes (EAPCs). Results: From 2000 to 2021, Brazil's population grew by 27%. Nationally, the asPR declined slightly from 1,503 to 1,495 per 100,000 [EAPC: -0.04% (95% CI: -0.05, -0.03)], with reductions observed in most regions. However, increases were noted in the North [EAPC: 0.14% (95% CI: 0.13, 0.15)] and Northeast [EAPC: 0.02% (95% CI: 0.01, 0.03)]. Males experienced greater reductions [EAPC: -0.16% (95% CI: -0.19, -0.13)] compared to females, who showed a slight increase [EAPC: 0.05% (95% CI: 0.03, 0.07)]. Projections indicate that asPR will decline nationally to 1,418 per 100,000 by 2050 [EAPC: -0.20% (95% CI: -0.20, -0.19)], with the South and Central West regions reducing the most.The asDALY rates declined from 142 to 104 per 100,000 [EAPC: -1.58% (95% CI: -1.69, -1.46)] during 2000-2021, with all regions showing decreases, particularly the Southeast [EAPC: -1.83% (95% CI: -1.98, -1.69)]. Nationally, projections suggest further reductions to 75 per 100,000 by 2050 [EAPC: -1.17% (95% CI: -1.22, -1.11)]. Conclusion: The burden of RHD in Brazil has decreased nationally and regionally over recent decades. Projections suggest that these trends will continue.