Factors Associated With Achalasia Treatment Outcomes: Systematic Review and Meta-Analysis

Abstract

This article has an accompanying continuing medical education activity, also eligible for MOC credit, on page page e76. Learning Objective-Upon completion of this activity, successful learners will be able to list the high resolution manometric criteria for diagnosis of achalasia types I, II, and III; list patient risk factors that could influence selection of myotomy procedure in patients with achalasia; recognize relative risks associated with the various treatment options for achalasia; and identify at least one predictive factor of successful outcome of pneumatic dilatation for treatment of achalasia. BACKGROUND & AIMS: Identification of factors associated with achalasia treatment outcome might help physicians select therapies based on patient characteristics. We performed a systematic review and metaanalysis to identify factors associated with treatment response. METHODS: We searched MEDLINE, EMBASE, and the Cochrane Library through February 21, 2019, for randomized controlled trials and cohort, case-control, and cross-sectional studies that reported patient-specific outcomes of treatment (botulinum toxin injection, pneumatic dilation, peroral endoscopic myotomy, or laparoscopic Heller myotomy). We assessed the methodologic quality of the included studies using the quality in prognosis studies tool. We planned qualitative and quantitative analyses. RESULTS: We analyzed data from 75 studies (8 randomized controlled trials, 27 prospective cohort studies, and 40 retrospective studies) on a total of 34 different factors associated with outcomes (3 demographic, 17 clinical, and 14 diagnostic factors). Qualitative assessment showed age, manometric subtype, and presence of a sigmoid-shaped esophagus as factors associated with outcomes of treatment for achalasia with a strong level of evidence. The cumulative evidence for the association with chest pain, symptom severity, and lower esophageal sphincter pressure was inconclusive. A meta-analysis confirmed that older age (mean difference, 7.9 y; 95% CI, 1.5-14.3 y) and manometric subtype 3 (odds ratio, 7.1; 95% CI, 4.1-12.4) were associated with clinical response. CONCLUSIONS: In a systematic review and meta-analysis, we found age and manometric subtype to be associated with outcomes of treatment for achalasia. This information should be used to guide treatment decisions.

2019 Seoul Consensus on Esophageal Achalasia Guidelines

“…The achalasia subtypes have been linked to the treatment response in multiple studies, including a recent systematic review and meta-analysis of manometric findings. 22 These findings should be used to guide treatment decisions. Multiple studies have reported different treatment success rates among the 3 achalasia subtypes, particularly, type III showing a higher likelihood of treatment failure compared to type II achalasia.…”

“…Multiple studies have reported different treatment success rates among the 3 achalasia subtypes, particularly, type III showing a higher likelihood of treatment failure compared to type II achalasia. 22,23 The inferior response of type III patients is often attributed to spastic contractions in the esophageal body. Pratap and colleagues found that type II predicted a good response to pneumatic dilatation.…”

“…(Level of evidence, low; strength of recommendation, weak) Experts' opinions: agree strongly (43.4%), agree with some reservations (37.0%), undecided (17.4%), disagree (2.2%), and disagree strongly (0.0%) Previous studies reported different success rates among the 3 achalasia subtypes; in particular, type III achalasia was associated with an increased risk of treatment failure compared to type II achalasia. 22,23 Type III achalasia is characterized by pathological mechanisms involving the esophageal body and the LES. 93 Therefore, the response rate to PBD or botulinum toxin injection is relatively low in patients with type III achalasia.…”

Comparative efficacy of first-line therapeutic interventions for achalasia: a systematic review and network meta-analysis

“…Additional patient-specific and resource considerations are relevant to choice of therapy. A recent systematic review and meta-analysis by Oude Nijhuis and colleagues additionally identified older age and presence of sigmoid-shaped esophagus as poor predictors of treatment success [27]. Health-care utilization is additionally an important consideration.…”

European guidelines on achalasia: United European Gastroenterology and European Society of Neurogastroenterology and Motility recommendations

“…Patient‐specific factors such as age, sex and manometric type are commonly believed to be predictive of treatment outcome, with the unfavourable effect of young age undoubtedly being the most frequently described example 66–69 . A recently published review systematically assessed 75 studies that investigated potential patient‐specific predictors 70 . A total of 34 predictors were identified, but of all pre‐therapeutic factors, only age and manometric subtype were identified as important predictors with a strong level of cumulative evidence.…”