Effects of viscosity and volume on the patterns of esophageal motility in healthy adults using high-resolution manometry

The purpose of this study was to determine the effects of age, sex, body mass index (BMI), viscosity, and volume on esophageal motility using high-resolution manometry (HRM). Manometric studies were performed on 60 asymptomatic volunteers (27 men and 33 women, age: 19-56 years) while in a supine position. Manometric protocol included 10 water swallows (5cc), 10 jelly swallows (5cc), and 1 water swallow (20cc). Evaluation of HRM parameters including length of proximal pressure trough (PPT length), distal latency (DL), contractile front velocity (CFV), distal contractile integral (DCI), and 4-second integrated relaxation pressure (IRP) was performed using MATLAB. Significant differences were noted in median IRP between water 5cc (median 7.2mmHg [range 5.5-9.6]), jelly 5cc (median 6.0mmHg [range 3.8-8.0]), and water 20cc {(Median 4.8mmHg [range 3.3-7.4]), P < 0.01}. DL were significantly different between water 5cc, jelly 5cc, and water 20cc (P < 0.01), and in terms of PPT, proportions of small (2cm ≤ < 5cm) and large (5cm≤) break for jelly 5cc were significantly higher than those for the water 5cc swallow (P < 0.05). Furthermore, DCI increased with age for water 5cc, and a significant negative correlation was noticed between proportions of small break and BMI for water 5cc. Manometric measurements vary depending on age, BMI, viscosity, and volume. These findings need to be taken into account in the interpretation of manometry results.