Background
Visceral hypersensitivity in functional dyspepsia can be localized or widespread, and there is no simple method of assessment. Measuring interoceptive accuracy at different sites provides an assessment of perceptual hypersensitivity to specific ecological phenomena. The purpose of this study was to characterize visceral hypersensitivity by comparing gastric sensory and cardiac perceptual tests in patients with postprandial distress syndrome and in healthy volunteers.
Methods
Sixteen patients with postprandial distress syndrome (age = 47.5 ± 17.4, all female) and 16 healthy volunteers (age = 43.3 ± 16.1, all female) participated in the study after a six-hour fast. Each participant answered questionnaires about physical and mental quality of life, depression and anxiety, tendency of alexithymia, and somatosensory amplification. After completing the questionnaire, the participants took the heartbeat tracking task and the five-minute water load test. We performed statistical analysis using the Mann–Whitney U test and Spearman’s rank correlation coefficient.
Results
Subjects with postprandial distress syndrome had a lower drinking capacity than healthy volunteers (postprandial distress syndrome = 360.9 ± 170.0 mL, healthy volunteers = 644.1 ± 297 mL, P = .009), but there was no significant difference in the heartbeat perception score (postprandial distress syndrome = 0.599 ± 0.175, healthy volunteers = 0.623 ± 0.181, P = .647). There was a negative correlation (r = − .509, P < .05) between drinking capacity and the heartbeat perception score in healthy volunteers, but no correlation in postprandial distress syndrome (r = − .156, P = .564). Heartbeat perception score did not correlate with psychological measures.
Conclusions
Compared with healthy volunteers, only the five-minute water load test values were reduced in patients with postprandial distress syndrome, and no difference was observed in the heartbeat tracking task. The cross-organ perceptual relationships observed in healthy volunteers were not present in patients with postprandial distress syndrome. Combining the five-minute water load test and heartbeat tracking task revealed visceral hypersensitivity confined to the stomach in patients with postprandial stress syndrome, suggesting that the problem may be limited to sensory processing in the stomach. Performing sensory examinations at two different sites may be useful in clarifying whether visceral hypersensitivity is localized.
Trial registration: UMIN000057586. Registered11 March 2023(retrospectively registered).