Different Clinical Features of Idiopathic Achalasia in Various Countries

Research gap in esophageal achalasia: a narrative review

In recent years, new translational evidence, diagnostic techniques, and innovative therapies have shed new light on esophageal achalasia and revamped the attention on this relatively rare motility disorder. This narrative review aims to highlight the most recent progress and the areas where further research is needed. The four senior authors identified five topics commonly discussed in achalasia management: i.e. pathogenesis, role of functional lumen imaging probe in the diagnostic flow chart of achalasia, how to define the outcome of achalasia treatments, how to manage persistent chest pain after the treatment, and if achalasia patients' may benefit from a regular follow-up. We searched the bibliographic databases to identify systematic reviews, meta-analyses, randomized control trials, and original research articles in English up to December 2023. We provide a summary with the most recent findings in each of the five topics and the critical points where to address future research, such as the immune-genetic patterns of achalasia that might explain the transition among the different phenotypes, the need for a validated clinical definition of treatment success, the use of neuromodulators to manage chest pain, and the need for identifying achalasia patients at risk for cancer and who may benefit of long-term follow-up. Although undoubtedly, progress has been made on the definition and management of achalasia, unmet needs remain. Debated aspects range from mechanistic insights, symptoms, objective measure relationships, and accurate clinical responses to therapeutic interventions. Translational research is eagerly awaited to answer these unresolved questions.

Global trends in incidence and prevalence of achalasia, 1925-2021: A systematic review and meta-analysis

BACKGROUND

Achalasia poses a significant socioeconomic burden, yet global trends remain undocumented. This study aims to describe the worldwide trends in the incidence and prevalence of achalasia from 1925 to 2021 and explore their correlation with various factors through a comprehensive systematic review.

METHODS

We searched the PubMed/MEDLINE, Embase, and Cochrane databases from inception to 30 June 2023, to identify studies reporting the incidence or prevalence of achalasia in the general population. This study utilized pooled estimates with 95% confidence intervals (CI) to estimate the incidence and prevalence of achalasia, and conducted various subgroup analyses.

RESULTS

A total of 26 eligible studies covering approximately 269 million participants and 20,873 patients from 14 countries across five continents were included. Global pooled incidence and prevalence of achalasia were estimated to be 0.78 cases per 100,000 person-years (95% CI, 0.64-0.93; number of studies, 26; sample population, 269,315,171) and 10.82 cases per 100,000 person-years (95% CI, 8.15-13.48; number of studies, 14; sample population, 192,176,076), respectively. The incidence of achalasia was higher in Oceania (than Asia and Africa) and in adults (than children) after the introduction of the Chicago classification. Prevalence followed a similar pattern. The pooled incidence of achalasia showed an overall upward trend from 1925 to 2021 (1925-1999; 0.40 [0.32-0.49] vs. 2018-2021; 1.64 [1.33-1.95] cases per 100,000 person-years).

CONCLUSIONS

The incidence and prevalence of achalasia have notably increased, particularly with advancements in diagnosis, and show significant variation worldwide, despite the large heterogeneity within the sample population. Further studies are necessary to accurately assess the global incidence and prevalence of achalasia.

Evaluating the molecular and genetic mechanisms underlying gut motility disorders

INTRODUCTION

Gastrointestinal (GI) motility disorders comprise a wide range of different diseases affecting the structural or functional integrity of the GI neuromusculature. Their clinical presentation and burden of disease depends on the predominant location and extent of gut involvement as well as the component of the gut neuromusculature affected.

AREAS COVERED

A comprehensive literature review was conducted using the PubMed and Medline databases to identify articles related to GI motility and functional disorders, published between 2016 and 2023. In this article, we highlight the current knowledge of molecular and genetic mechanisms underlying GI dysmotility, including disorders of gut-brain interaction, which involve both GI motor and sensory disturbance.

EXPERT OPINION

Although the pathophysiology and molecular mechanisms underlying many such disorders remain unclear, recent advances in the assessment of intestinal tissue samples, genetic testing with the application of 'omics' technologies and the use of animal models will provide better insights into disease pathogenesis as well as opportunities to improve therapy.