Epidemiology and practice patterns of achalasia in Taiwan: A nationwide population-based cohort study

Background: Achalasia is a rare disease of gastrointestinal motility characterized by impaired esophageal peristalsis and reduced esophageal sphincter relaxation. However, data on its epidemiology and outcomes in Taiwan are limited. This study aimed to assess the incidence, characteristics, and clinical management of achalasia in Taiwan. Methods: Patients who were newly diagnosed with achalasia between 2001 and 2013 were recruited from the Taiwan National Health Insurance Research Database. The study obtained data on the age, sex, urbanization, socioeconomic status, area of residence, diagnostic methods, and interventional management of the patients. Incidence, diagnostic modalities, treatment methods, malignancy, and mortality outcomes were analyzed. Results: In total, 206 new achalasia cases were identified. The mean annual incidence in Taiwan was 1.64 (95% confidence interval 1.22-2.05) per 100,000 persons. The mean age of the patients at diagnosis was 51.8 years. The age-specific incidence of achalasia peaked in patients aged between 70-80 years and above 80 years. For achalasia diagnosis, endoscopy, computed tomography (CT), barium studies, and manometry were performed in 123 (59.71%), 97 (47.09%), 49 (23.79%), and 11 patients (5.34 %), respectively. During long-term follow-up, seven patients (3.39%) developed esophageal cancer, and 39 patients (18.93%) died. The median survival was 10.65 years after achalasia diagnosis, with a 10-year survival rate of 76.22%. Conclusion: This is the first population-based epidemiological study on achalasia in Taiwan, revealing the incidence of achalasia before the era of high-resolution manometry. Clinicians should be vigilant about the development of esophageal cancer and mortality during long-term follow-ups. There is also room to enhance the utilization of various diagnostic tools for achalasia.