Leprosy relapse after multidrug therapy: Systematic review and meta-analysis.

<h4>Objective</h4>To synthesize the scientific evidence regarding the prevalence of leprosy relapse following multidrug therapy.<h4>Method</h4>A systematic review was conducted following the JBI methodology for prevalence studies and reported according to the guidelines, with the registration number CRD42020177141. The inclusion criteria were based on the mnemonics (Population, Condition, Context). Population: Individuals of any age or sex diagnosed with leprosy relapse and previously treated with paucibacillary or multibacillary multidrug therapy. Conditions: Leprosy relapse after multidrug therapy, measured as the proportion of cases. Context: Studies conducted within the healthcare service settings. The databases searched included Medline, Latin American and Caribbean Health Sciences Literature (LILACS), Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Scopus, WoS, and Caribbean Public Health Agency (CARPHA). The references were managed using Mendeley. A random-effects meta-analysis model was employed, and heterogeneity was assessed using Higgins' I² statistics.<h4>Results</h4>Of 26 studies (a combined sample of 71,385 participants), 19 were included in the meta-analysis. A higher prevalence of relapse was observed in working-age males, multibacillary cases with a high bacillary load, and those with established physical disabilities. The estimated prevalence of relapse across studies ranged from 0% to 10%, with a pooled estimate of 4% in India (95% CI: 0.03-0.05). The overall point estimate for relapse using regular multidrug therapy was 0.04 (95% CI: 0.02-0.05).<h4>Conclusion</h4>The prevalence of relapse varied according to the geographic location and type of multidrug therapy, with substantial heterogeneity across studies. These findings suggest that factors such as individual patient characteristics, treatment adherence, and capacity for healthcare services may have influenced the outcomes observed in this review.