Development of Dilated Esophagus, Sigmoid Esophagus, and Esophageal Diverticulum in Patients With Achalasia: Japan Achalasia Multicenter Study

BACKGROUND/AIMS: Patients with achalasia-related esophageal motility disorders (AEMDs) frequently present with dilated and sigmoid esophagus, and develop esophageal diverticulum (ED), although the prevalence and patients characteristics require further elucidation. METHODS: We conducted a multicenter cohort study of 3707 patients with AEMDs from 14 facilities in Japan. Esophagography on 3682 patients were analyzed. RESULTS: Straight (n = 2798), sigmoid (n = 684), and advanced sigmoid esophagus (n = 200) were diagnosed. Multivariate analysis revealed that long disease duration, advanced age, obesity, and type I achalasia correlate positively, whereas severe symptoms and integrated relaxation pressure correlate negatively with development of sigmoid esophagus. In contrast, Grade II dilation (3.5-6.0 cm) was the most common (52.9%), while grade III dilation (≥ 6 cm) was rare (5.0%). We found early onset, male, obesity, and type I achalasia correlated positively, while advanced age correlated negatively with esophageal dilation. Dilated and sigmoid esophagus were found mostly in types I and II achalasia, but typically not found in spastic disorders. The prevalence of ED was low (n = 63, 1.7%), and non-dilated esophagus and advanced age correlated with ED development. Patients with right-sided ED (n = 35) had a long disease duration (P = 0.005) with low integrated relaxation pressure values (P = 0.008) compared with patients with left-sided ED (n = 22). Patients with multiple EDs (n = 6) had lower symptom severity than patients with a single ED (P = 0.022). CONCLUSIONS: The etiologies of dilated esophagus, sigmoid esophagus, and ED are considered multifactorial and different. Early diagnosis and optimal treatment of AEMDs are necessary to prevent these conditions.