Botulinum toxin injections for achalasia symptoms can approximate the short term efficacy of a single pneumatic dilation: a survival analysis approach

Abstract

Objective: Botulinum toxin injection can induce a temporary symptomatic remission in some patients with achalasia, but the comparative utility of the approach is not fully known. This study used survival analysis methods to better understand the ability of single or repeated botulinum toxin injections to postpone the need for other treatments.

Methods: The response to botulinum toxin in 42 patients with idiopathic achalasia who had not received prior treatment was compared with the outcome in 26 consecutive patients who underwent initial treatment with pneumatic dilation. Survival analysis methods were employed using time to retreatment as the principal outcome measure.

Results: Retreatment (any type) was required in 50% of subjects at 265 days (0.73 yr) after the first botulinum toxin injection. In contrast, retreatment after initial pneumatic dilation was required in <40% of patients after 2 and 5 yr of follow-up. The curves became significantly separated (p < 0.05) within 1 yr after initial treatment. Of those treated solely with botulinum toxin injections, repeated as needed, only 46% required pneumatic dilation or surgery by 2 yr. Survival analysis curves for repeated injections and initial pneumatic dilation did not differ statistically at 1 or 2 yr (p = 0.5 and p = 0.4, respectively). Correlational analyses indicated that, of the clinical parameters tested, only the degree of dysphagia for liquids was useful in selecting the better responders to botulinum toxin injections, with lesser symptoms predicting longer time to retreatment.

Conclusions: Botulinum toxin injections, repeated as needed, can approximate the benefits of a single pneumatic dilation for < or = 2 yr from the standpoint of usual factors that drive further management.