Six months fixed duration multidrug therapy in paucibacillary leprosy: risk of relapse and disability in Agra PB cohort study

BACKGROUND: Many studies have focused on multidrug therapy (MDT) for multibacillary (MB) leprosy and rarely on long-term outcome of paucibacillary (PB) leprosy having recommendation of therapy for 6 months fixed duration therapy for PB patients. Studies on measuring risk of disability are rare. The present study is to assess the cure; default, relapse and disability in a prospective cohort of PB leprosy during follow-up of >4 years after treatment. DESIGN: Prospective. SETTING: Primary in our field area of Agra District. PARTICIPANTS: 920 PB leprosy patients entered the study, 621 completed treatment, 599 followed finally including 271 males, no ethnic differentiation, patients of all age groups except for children below 5 years and old persons above 70 years were not included. TREATMENT: 6 months fixed duration MDT as recommended by WHO. PRIMARY AND SECONDARY OUTCOMES: Treatment completion, cure, relapse and development of disability based on clinical assessment by well-experienced doctors. STATISTICAL METHODS: Data have been analysed using SPSS software, risk is computed as incidence per 100 person–years (PY) and test of significance used. RESULTS: Study reports 91% cure rate. Incidence of relapse was 1.3/100 PY with no significant variation by age, sex, delay in detection, patches and nerves. Crude incidence of disability was 2.2% and varied significantly by age and nerve thickening but not by sex, number of patches, nerves and delay in treatment. Incidence of disability was 0.50/100 PY in treatment completed and 0.43 among defaulters. CONCLUSION: The study concludes that relapses do occur after MDT treatment but at the level of 1–2%, incidence of disability remains low (<1/100 PY) in PB leprosy. Low incidence of relapse and disability suggests that 6 months therapy is quite effective. However, further improvement may help to improve its efficacy. Longer follow-up may add to efficacy measures.