Global, regional, and national burden and trends of congenital birth defects from 1990 to 2021: epidemiological trends, health inequalities, and COVID-19 impact.

Background: Congenital birth defects remain a leading cause of mortality and disability in younger populations aged <14 years, however, little comprehensive or recent evidence of the burden of congenital birth defect and its subtypes are available globally. Additionally, the extent of regional health inequality and the effects of the coronavirus disease 2019 (COVID-19) pandemic on congenital birth defects remain unclear. This study leverages 2021 Global Burden of Disease (GBD) data to conduct a comprehensive assessment of the global epidemiological profile, health inequality, and the repercussions of the COVID-19 on congenital birth defects, with the goal of guiding optimal medical resource allocation. Methods: The research encompassed the congenital birth defect burden from 204 countries and territories, analyzing key metrics such as prevalence, age-standardized prevalence rate (ASPR), incidence, age-standardized incidence rate (ASIR), mortality, age-standardized death rate (ASDR), years lived with disability (YLD), and age-standardized YLD rate (ASYR) from 1990 to 2021. The study employed the slope index of inequality (SII) and concentration index (CI), as advocated by the World Health Organization (WHO), to scrutinize health inequalities among nations with varying socio-demographic index (SDI) levels. Additionally, the potential impact of the COVID-19 pandemic on congenital birth defect disease burden was evaluated. Results: In 2021, congenital birth defects led to an estimated 530,946.58 deaths [95% uncertainty interval (UI): 642,418.94 to 454,278.97] and 52,325,332.69 YLDs (95% UI: 62,682,127.14 to 45,186,944.83) globally, marking a decline of 44.05% and 62.17% respectively compared to 1990. Notably, over 80% of these fatalities occurred among children and adolescents (aged <14 years). The ASIR of congenital birth defect only saw a modest 4.26% decline. Congenital heart anomalies and congenital musculoskeletal and limb anomalies emerged as the congenital birth defects with the highest ASIR, accounting for the most significant ASDR and ASYR burdens, respectively. Neural tube defects, despite their high fatality rates, exhibited a 36.91% ASIR decrease over the three decades. Males exhibited a higher disease burden than females. Notable regional health inequality was identified; with highest ASIR burdens were concentrated in low SDI regions like Africa, as well as in countries with high rates of consanguineous marriages, including the Central African Republic, Tajikistan, and Brunei Darussalam. The CI and SII confirmed a significant clustering of congenital birth defects in low SDI areas, with health inequalities remaining largely unchanged over the past three decades. The COVID-19 pandemic did not significantly affect the overall incidence of congenital birth defects but may have associations with certain subtypes, such as chromosomal abnormalities and cleft lip and palate. Conclusions: From 1990 to 2021, mortality and disability of congenital birth defect have significantly decreased, yet the incidence has remained largely unchanged, underscoring the need for improved screening strategies.