Regional gastrointestinal contractility parameters using the wireless motility capsule: inter-observer reproducibility and influence of age, gender and study country.

Background: The wireless motility capsule concurrently measures temperature, pH and pressure as it traverses the gastrointestinal tract. Aims: To describe normative values for motility/contractility parameters across age, gender and testing centres. Methods: Healthy participants underwent a standardised wireless motility capsule assessment following an overnight fast and consumption of a meal of known nutritional content. Traces were divided into regions of interest and analysed using 2 software packages (MotiliGI and GIMS Data Viewer). Inter-observer agreement was independently assessed by 2 investigators. Results: Normative data for motility/contractility parameters (maximum amplitude, mean peak amplitude, contraction frequency and motility index) are presented for 107 individuals (62 male, median age 40years, range 18-78). MotiliGI-Gastric, small bowel and colonic maximal contraction amplitude correlated with age (r = .24, P = .01; r = .22, P = .02; and r = .2, P = .04 respectively). Small bowel motility index was higher in females than males (150.412 vs 122 +/- 7.6, P = .04). Inter-observer agreement was excellent for transit times, pH and contractility/motility parameters. GIMS Data viewer-Gastric, small bowel and colonic log(e) motility index correlated with the respective area under the contraction curve, total contractions, sum of amplitudes and contraction frequency (all r>.35, P < .0003) but not with transit times. Conclusions: Our analysis provides normative data for motility/contractility parameters. Log motility index summarises a number of measures. In future, the measurement of contractile activity with the wireless motility capsule may potentially aid in the diagnosis of disease states such as visceral myopathic disorders.