Mid-Term and Long-Term Outcomes of Peroral Endoscopic Myotomy for the Treatment of Achalasia: A Systematic Review and Meta-Analysis

Background and Aims Peroral endoscopic myotomy (POEM) achieves a satisfactory short-term clinical response in patients with achalasia. However, data on mid- and long-term clinical outcomes are limited. We aimed to assess the mid- and long-term efficacy and safety of POEM in achalasia patients. Methods Using the pre-designed search strategy, we identified relevant studies that evaluated the efficacy and safety of POEM with a minimum of 2-year follow-up in the Embase, Cochrane, and PubMed databases from inception to January 2021. Primary outcome was pooled mid- and long-term clinical success rate based on the Eckardt score. Secondary outcome was pooled long-term reflux-related adverse events. Results A total of 21 studies involving 2,698 patients were included. Overall, the pooled clinical success rates with 2-, 3-, 4-, and 5-year follow-ups were 91.3% (95% confidence interval [CI] 88.4-93.6%), 90.4% (95% CI 88.1-92.2%), 89.8% (95% CI 83.6-93.9%), and 82.2% (95% CI 76.6-86.7%), respectively. Besides, the pooled long-term clinical success rates for type I, II, and III achalasia were 86.1% (95% CI 80.9-90.1%; I-2 = 0%), 87.9% (95% CI 84.2-90.8%; I-2 = 48.354%), and 83.9% (95% CI 72.5-91.2%; I-2 = 0%), respectively. Moreover, the pooled incidence of symptomatic reflux and reflux esophagitis was 23.9% (95% CI 18.7-29.9%) and 16.7% (95% CI 11.9-23.1%), respectively. Conclusions POEM is associated with a long-term clinical success of 82.2% after 5 years of follow-up. Randomized control trials comparing POEM with laparoscopic Heller myotomy or pneumatic dilation with longer follow-up periods are needed to further demonstrate the long-term safety and efficacy of POEM.