Sustained clinical outcomes at long-term follow-up after peroral endoscopic myotomy for achalasia: a multicentre cohort study.

BACKGROUND: Peroral endoscopic myotomy (POEM) is an established treatment for achalasia, achieving >90% short-term clinical success. However, long-term durability remains less clear. This study evaluates POEM outcomes beyond 5 years in a multi-centre cohort. AIMS: This study evaluates POEM outcomes beyond 5 years in a multi-centre cohort. METHODS: Patients with achalasia who underwent POEM across four Australian tertiary centres (January 2014-January 2020) were prospectively enrolled. Eckardt scores were recorded pre-treatment and at multiple intervals up to ≥5 years after POEM. Primary outcome was clinical success at ≥5 years, defined as Eckardt score ≤3 without need for re-intervention. Secondary outcomes included risk factors for failure and management strategies. RESULTS: Of 221 eligible patients, 153 (69.2%) had ≥5-year follow-up data available, with median follow-up of 6.5 years (interquartile range (IQR) 5.6-7.6). Achalasia subtypes included type I (23.5%), type II (62.1%) and type III (14.4%). Among the patients, 52.3% were treatment-naïve; prior therapies included laparoscopic Heller myotomy (14.3%), botulinum toxin (17.0%) and pneumatic balloon dilation (30.7%). Clinical success at ≥5 years was observed in 118 (77.1%) patients. Median Eckardt scores improved from 8.0 (IQR 6.0-10.0) before POEM to 0.0 (IQR 0.0-1.0) at 3-6 months, 1.0 (IQR 0.0-2.0) at 2 years and 2.0 (IQR 0.0-3.0) at 5 years. Sustained success was associated with lower baseline Eckardt scores (P = 0.033). Prior lower oesophageal sphincter (LOS)-directed therapy predicted failure (odds ratio 3.80, P < 0.001). Age, achalasia subtype, myotomy characteristics and post-POEM endoscopy findings were not predictive. CONCLUSION: POEM provides durable symptom relief beyond 5 years for achalasia. Higher pre-POEM symptom burden and prior LOS-directed interventions are associated with reduced long-term success.