Patient factors do not predict symptomatic response to botulinum toxin for the treatment of anal fissure

Abstract

Background: Botulinum toxin (Botox) is being used increasingly for the treatment of anal fissures despite variable success rates reported in the literature. Our aim was to further characterise the role of patient factors in the response to Botox therapy in order to improve response rates. Methods: A retrospective case note review of patients who received Botox was performed over a twelve-year period (1999-2011). Responder and non-responder cohorts were compared to identify any differences between groups. Statistical analysis using chi-square and logistic regression analysis were used to compare the groups. Results: 192 patients were included in study. All patients received Botox injection type A for anal fissure with average dose 40 Units (range 20-80units). A total of 166 of 192 patients in total responded (86.5% with 71.4% after the 1 st injection and a further 15.1% after a 2 nd Botox injection). Comparison of responder and non-responder cohorts revealed no significant difference in age or gender. Similarly there was no significant difference in the type of fissure, duration of symptoms or position of fissure or prior use of topical therapy. Conclusions: Botox is effective in the management of anal fissure however patient factors do not appear to predict response to Botox therapy.