Effect of botulinum toxin injection for achalasia in Thai patients

Achalasia is a disorder of the esophagus. The lower esophageal sphincter fails to relax and increases the loss of body peristalsis. It is an uncommon disease worldwide. Data regarding its treatment are derived mostly from North America and European countries. Few data regarding this treatment were available in Asia and no data about using botulinum toxin injection for this disease was available in Thailand.

To evaluate the efficacy of botulinum toxin in achalasia in Thai patients.

Eleven achalasia adult Thai patients with a mean age of 56.5 +/- 16.9 were studied. There are nine females and two males. The duration of symptom before treatment was 27.5 +/- 34.5 months. All patients receiving botulinum toxin injection at Siriraj hospital between 2001 and 2006 were retrospectively reviewed. Pretreatment of baseline lower esophageal sphincter, symptom score and body weight were compared. Time to second botulinum toxin injection or the need to receive treatment for recurrence was recorded to evaluate the time of recurrence. Adverse events from this procedure were collected.

Eleven patients were involved in this study. One patient that received 40 units of botulinum toxin showed no response after a six months follow up. The other ten patients received botulinum toxin 80 units for each session and were enrolled in this study. All ten patients demonstrated good response to the first botulinum toxin injection and subsequent injections. Four patients received only one session of botulinum toxin injection during study period. Meanwhile, five patients received two sessions and only one patient required four sessions. Symptom score of all ten patients improved significantly compared with pretreatment score (7.3 +/- 1.3 for pretreatment and 0.4 +/- 0.5, 0.9 +/- 0.7 and 1.6 +/- 1.3 after 2 weeks, 3 months and 6 months, respectively). Body weight increased significantly when compared with pretreatment (47.7 +/- 6.5 Kg for pretreatment and 49.2 +/- 5.8, 50.5 +/- 6.4, and 50.7 +/- 5.8 Kg after 2 weeks, 3 months, and 6 months, respectively). Previous treatments prior botulinum toxin injection do not seem to influence the effect of this treatment. Mean time of recurrence is 444 +/- 132 days (270-718 days). Minor adverse events such as chest pain and reflux symptoms were seen in this therapy.

Botulinum toxin injection in Thai achalasia patients is an effective, simple, and safe treatment. These results showed the similar outcomes as in Caucasian patients.