POEM for Achalasia Has Comparable Clinical Success Rates in Eastern and Western Countries

Clinical success rates for peroral endoscopic myotomy (POEM) in patients with achalasia are high and similar in Eastern and Western countries, according to a study in Diseases of the Esophagus.

Researchers conducted a systematic review and meta-analysis to compare clinical outcomes of POEM for achalasia between Eastern and Western countries.

A search in the PubMed, EMBASE, Web of Science, and Cochrane Library databases was performed for relevant studies from inception to December 31, 2021. Eligible studies included patients with achalasia from Eastern countries, such as China, India, and Japan, or Western countries, such as the United States and Australia. The intervention was POEM, and the outcome was clinical success rate based on Eckardt score less than or equal to 3.

The pooled clinical success rate was the primary outcome.

The analysis included 29 studies — 18 Eastern studies with 5,962 patients and 11 Western studies with 1651 patients. In Eastern countries, China, with 13 studies, was the primary country of origin, and among Western countries, the United States, with 7 studies, was the primary country of origin. All studies were conducted from 2009 to 2021 with follow-up of 12 to 49.3 months.

Clinical success without recurrence was achieved in 5,852 patients during the follow-up of over 1 year. Clinical success occurred in 18 Eastern studies among 4439 of 4824 patients and in 11 Western studies among 1,413 of 1,526 patients. Overall, POEM’s clinical success rate was 92.6% (95% CI, 90.9%-94.0%; I²=77.750%). The pooled clinical success rate for POEM was equal in Eastern studies (92.8%; 95% CI, 90.9%-94.2%) vs Western studies (91.8%; 95% CI, 86.7%-95.1%).

POEM had an overall technical success rate of 99.5% (95% CI, 99.1%-99.7%; I²=50.874%). The pooled technical success rate for POEM was comparable in the Eastern and Western studies (99.4% vs 99.6%, respectively).

For adverse events, the overall rate for POEM was 7.7% (95% CI, 5.3%-11.2%; I²=65.105%). The Eastern studies had a slightly lower pooled incidence of procedure adverse events (6.6%; 95% CI, 3.7%-11.7%) vs Western studies (8.7%; 95% CI, 5.3%-13.9%).

The total incidence of symptomatic reflux was 20.9% (95% CI, 18.2%-24.0%), and the total incidence of reflux esophagitis was 28.3% (95% CI, 22.1%-35.6%).

The pooled procedure time for POEM was shorter among the Eastern studies vs the Western studies (61 minutes vs 80 minutes, respectively), and the length of hospital stay was greater in the Eastern studies vs the Western studies (5.8 days vs 2.4 days, respectively).

Among individual countries, Japan ranked first in clinical success, with a total clinical success rate of 95.9% (95% CI, 92.2%-97.8%). India had a greater incidence of adverse events compared with other countries, with an overall adverse event rate of 21.3% (95% CI, 6.3%-52.1%)

Among several limitations, classification of Eastern and Western countries followed a previous meta-analysis study, and so the number of studies and cases in Eastern countries was much higher than those of Western countries. Also, most studies were retrospective, heterogeneity occurred, and the research institutions were large-scale, tertiary medical institutions with advanced POEM experience.

“The clinical success rate and technical success rate are both high in Eastern and Western countries, but Eastern countries show better POEM outcomes compared to Western countries in terms of adverse events rate and procedure time,” study authors concluded. “However, Eastern countries still need to make efforts to reduce the length of hospital stay.”