Trend and Burden of Vitamin A Deficiency in 1990-2021 and Projection to 2050: A Systematic Analysis for the Global Burden of Disease Study 2021.

: In this study, we aim to provide an update on the global, regional, and national trends in VAD-associated mortality and morbidity for children under 20 years of age, across different age groups and sociodemographic backgrounds, to identify populations at risk that require further attention. : Data from the Global Disease of Burden study were analysed to determine the temporal trends in VAD mortalities and VAD disease burden through disability-adjusted life years (DALYs) and Years Lived with Disability (YLD). Data on children under 20 years of age from 1990 to 2021 from 204 countries and territories were included for analysis. The Average Annual Percentage Change (AAPC) was used to show a temporal trend over a 30-year period. : Global VAD-associated mortality has decreased significantly, with an AAPC of -0.91 (95% CI= -0.95 to -0.85). No significant improvements in VAD morbidities were identified across Sub-Saharan African regions. In Central Sub-Saharan Africa, the number of VAD-associated disabilities increased from 70,032.12 to 73,534.15. Significant heterogeneity in changes in VAD morbidities were also identified across different countries. The highest age-standardized rate (ASR) of VAD YLD was 282.36 in Somalia, while countries with high sociodemographic indices had an ASR of 0. : Significant global improvements in VAD mortalities indicate the efficacy of wide-scale high-dose vitamin A supplementation for children under 5 years of age. However, the lack of improvements in VAD morbidities in low-SDI countries highlights the need to continue crucial high-dose vitamin A supplementation and to implement additional vitamin A supplementation programs.