Relationship between upper esophageal sphincter abnormalities and esophageal motility disorders

Objective To evaluate the relationship between upper esophageal sphincter (UES) abnormalities and esophageal motility disorders. Methods We performed a retrospective study of 447 patients undergoing high resolution esophageal manometry (HRM) at our Digestive Endoscopic Center from November 2014 to October 2015. Patients were divided into normal upper esophageal sphincter resting pressure (UESP) group (n=349) and abnormal UESP group, including hypertensive group (n=29), hypotensive group (n=69), or normal upper esophageal sphincter relaxation pressure (UESRP) group (n=355) and impaired relaxation group (n=92). Clinical data and HRM data were compared. Results Patients with hypotensive UESP were older than those with normal UES function (55.62±11.71) years vs (45.79±13.66) years, P＜ 0.000 1, while patients with hypertensive UESP were younger compared with those with normal UESP (40.62±9.72) years vs (45.79±13.66) years, P=0.012. In respect of clinical symptoms, dysphagia occurred in 20 (69.0%) patients with UESP hypertensive and 65 (70.0%) patients with impaired UES relaxation, which were significantly higher than UES normal patients (P＜ 0.001). In patients with UES impaired relaxation, incidences of symptoms including acid reflux and heartburn, retrosternal pain were significant lower than those of UES normal group (P=0.001, P=0.026). Patients with hypertensive UES resting pressure or impaired UES relaxation were significantly more likely to have achalasia Ⅱ as compared with those with normal UES function (P＜ 0.001). In additional, 70 (76.1%) patients with impaired UES had integrated relaxation pressure (IRP) abnormality simultaneously. Conclusion Our study shows a negative correlation between age and UESP. Hypertensive UESP and impaired UES relaxation have relationship with some clinical symptoms such as dysphagia. Also, there is a high frequency of UES abnormalities observed in patients with manometric diagnosis of achalasia Ⅱ. Majority of impaired UES relaxation patients have IRP abnormalities.