Thirty Years of Trends in Leprosy Burden and Associated Socioeconomic Status in Asia: Spatiotemporal Analysis of The Global Burden of Disease Study

Introduction: Leprosy is a neglected tropical disease that imposes a disproportionate caseload burden on Asia. This study analyzed spatiotemporal trends of leprosy incidence and disability-adjusted life-year (DALY) in Asia from 1990 to 2021 and assessed their association with socioeconomic status. Methods: Using Global Burden of Disease 2021 data (1990–2021), we analyzed temporal trends in age-standardized incidence rates (ASIR) and DALY rates (ASDR) for leprosy in Asia with Estimated Annual Percentage Change (EAPC). Results were mapped geographically to visualize spatial patterns. Associations with Socio-demographic Index (SDI) were analyzed using Spearman correlation, followed by multivariable linear regression adjusting for sex and country. Results: From 1990 to 2021, the estimated incidence of leprosy in Asia declined by 50.01%. Both estimated ASIR and ASDR of leprosy in Asia also decreased (EAPC of ASIR -3.62, EAPC of ASDR -3.16). ASIR decreased from 2.23 (1990) to 0.63 per 100,000 persons (2021) and ASDR decreased from 0.78 (1990) to 0.28 per 100,000 persons (2021). However, the estimated burden varies across observed countries. Strong negative correlations were observed between SDI and both estimated ASIR (ρ = -0.74) and ASDR (ρ = -0.85) (both P < 0.001). Multivariable regression demonstrated that SDI was independently associated with both ASIR (β = -7.61) and ASDR (β = -3.05) (both P < 0.001) after adjusting for sex and country. Sex and country were also significant predictors (P < 0.001). Higher estimated burdens were observed in males. Conclusion: Socioeconomic development, measured through SDI, was the primary driver of leprosy reduction. Significant sex and country factors, as well as persistent cases, indicate the need for targeted, context-specific interventions.