Temporal Trends and Regional Variations in Prevalence of Neural Tube Defects across Middle East and North Africa Countries (1990–2023): A Bayesian Multilevel Analysis

A BSTRACT Background: Neural tube defects (NTDs) are severe congenital anomalies associated with high infant mortality, lifelong disability and substantial healthcare costs. Prevalence remains disproportionately high in the Middle East and North Africa (MENA) region due to folate deficiency, consanguinity, maternal metabolic conditions, environmental exposures and conflict-related stressors. Despite strong global evidence for folic acid fortification and supplementation, implementation across MENA has been uneven. Method: This study utilized data from Global Burden of Disease 2023 study and employed a multilevel Bayesian model. Posterior estimates were obtained via Markov Chain Monte Carlo simulation. Aims: This study aimed to assess temporal trends and between-country variation in age-standardised NTD prevalence across MENA from 1990 to 2023 and to identify high-risk countries using Bayesian multilevel modeling. Results: Afghanistan (21.47 per 100,000), Saudi Arabia (13.76) and Sudan (6.58) had the highest initial prevalence, whereas Jordan (−9.02), the Syria (−4.85), Bahrain (−4.75), Palestine (−4.41) and Iraq (−4.05) reported the lowest rates. Regarding trends, Afghanistan (−0.32) and Saudi Arabia (−0.29) experienced a significant decrease relative to the regional trend, whereas Jordan (0.15) and Syria (0.10) showed a significant higher trend in prevalence. Qatar (−0.09) was the only other country with a significant decreasing trend. The trend for most other countries was not statistically significant and did not differ from the regional trend. Conclusion: This analysis highlights persistent NTD burdens in MENA, with Afghanistan as a high-risk area despite overall declines and Jordan and Syria with a relative increasing trend. Urgent interventions, including mandatory folic acid fortification of staples (with Vitamin B12), prenatal screening and protections in conflict zones, are recommended to reduce prevalence and promote health equity.