Disparities in leprosy relapse from 2001 to 2022 in Brazil

Objective: to evaluate disparities in leprosy relapse in Brazil from 2001 to 2022. Methods: an ecological time series study was conducted. The ratio of leprosy relapses and new cases was obtained per 10,000, and it was adjusted secondarily according to region, sex, age group, operational classification, and smear microscopy outcomes. The temporal trends were estimated using Prais-Winsten regression analysis, and the comparisons were carried out using Negative Binomial regression. The significance level was adjusted at 5%. Results: the ratio of leprosy relapses per 10,000 new cases was approximately 424, considering 33,198 relapses and 783,704 new cases. The temporal trends were increasing across all Brazilian regions, sexes, operational classifications, and among individuals aged 15 years or older (all p-values <0.05). Stationarity trends were observed among individuals under 15 years (p-value = 0.422) and among smear microscopy outcomes (positive or negative, p-value = 0.147 and 0.156, respectively). Considering the comparison of ratios, significantly higher values were observed in the South region compared to the national estimate, as well as among males, individuals aged 15 years or older, multibacillary cases, and individuals with positive smear microscopy in relation to their respective counterparts (all p-value <0.001). In addition, a significantly lower value was observed in the Central-West region compared to the national estimate (p-value <0.001). Conclusion: in relation to new cases, there was an increase in leprosy relapses from 2001 to 2022 in Brazil, in addition to significant sociodemographic and clinical disparities.