Endoscopic pneumatic dilation versus botulinum toxin injection in the management of primary achalasia.

BACKGROUND Achalasia is an oesophageal motility disorder, of unknown cause, which results in increased lower oesophageal sphincter (LOS) tone and symptoms of difficulty swallowing. Treatments are aimed at reducing the LOS tone. Current endoscopic therapeutic options include pneumatic dilation (PD) or botulinum toxin injection (BTX). OBJECTIVES The objective of this review was to compare the efficacy and safety of two endoscopic treatments, pneumatic dilatation and intrasphincteric botulinum toxin injection, in the treatment of oesophageal achalasia. SEARCH STRATEGY We searched the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group trials register, the Cochrane Central Register of Controlled Trials, MEDLINE (1966 to Oct 2005), EMBASE (1980 to Oct 2005), BIOSIS (1969 to Oct 2005) and Web of Science (1955 to October 2005). We also searched abstracts from significant Gastroenterology meetings (DDW, UEGW) and reference lists of articles. SELECTION CRITERIA Randomised controlled trials comparing PD to BTX injection in patients with primary achalasia. DATA COLLECTION AND ANALYSIS Two review authors independently performed quality assessment and data extraction. MAIN RESULTS Six studies involving 178 participants were included. Two studies were excluded from the meta-analysis of remission rates on the basis of clinical heterogeneity of the initial endoscopic protocols. There was no significant difference in remission between PD or BTX treatment within four weeks of the initial intervention, with a relative risk of remission of 1.15 (95% CI 0.95 to 1.38, P = 0.39) for PD compared to BTX. There was also no significant difference in the mean oesophageal pressures between the treatment groups; weighted mean difference for PD of -0.77 (95% CI -2.44 to 0.91, P = 0.37). Data on remission rates following the initial endoscopic treatment was available for two studies at six months and three studies at 12 months. At six months 22 of 29 PD participants were in remission compared to 7 of 27 in the BTX group, giving a relative risk of 2.90 (95% CI 1.48 to 5.67, P = 0.002); whilst at 12 months 33 of 47 PD participants were in remission compared to 11 of 43 BTX participants, relative risk of 2.67 (95% CI 1.58 to 4.52, P = 0.0002). No serious adverse outcomes occurred in participants receiving BTX, whilst PD was complicated by perforation in three cases. AUTHORS' CONCLUSIONS The results of this meta-analysis would suggest that PD is the more effective endoscopic treatment in the long term (greater than six months) for patients with achalasia.