Introduction
Gastric emptying (GE) of liquids and solids is differentially regulated. GE of liquids follows an exponential kinetic and mainly depends on fundic tone, GE of solids requires trituration by antral contractions for passage through the adequately opened pylorus into the duodenum. Adler et al. showed that liquid GE was more often delayed in systemic sclerosis patients compared with GE of solids (Rheumatology 2022), but knowledge on the association between GE of solids and liquids in dyspeptic patients, in general, is limited.
Aims & Methods
To investigate this association and the correlation of GE times with symptoms, we compared results of breath tests using 13C-acetate (13C-ABT, GE-liquids) and 13C-octanoic acid (13C-OBT, GE-solids) in consecutive dyspeptic patients undergoing both tests (Keller et al. UEG J 2021). Normal ranges at our institution for 13C-ABT are 20-35 min (T lag-liquids), for 13C-OBT 50-150 min (T ½-solids). All patients additionally answered the gastroparesis cardinal symptom index questionnaire (GCSI, Revicki APT 2003).
Results
302 patients were included (230 women, age 45.9 (31.7-59.5) yrs, median(IQR)). Median T lag-liquids was 25 (20-35) min, median T ½-solids 78 (60-104) min. T lag-liquids and T ½-solids were weakly associated (R=0.165, p=0.002). Both were indirectly correlated with age (R=-0.280, p<0.0001 and R=-0.179, p=0.0009, resp), and similar in men and women. Concordant results for both tests were achieved in 172 subjects (57.6%): Both were normal in 161 (53.3%), both showed accelerated GE in 10 (3.3%) and both delayed GE in 3 (1%) subjects. Discrepant results were observed in 128 subjects (42.4%), in the vast majority of these, one of the tests was normal, but in 7 subjects (2.3%), GE was accelerated in one test, delayed in the other. 67 patients (22.2%) had delayed GE in at least one of the tests. Only in this subgroup, GE time correlated significantly with GCSI (R=0.242, p=0.024), in particular with the nausea/vomiting subscale (p=0.009).
Conclusion
In a large group of dyspeptic patients, more than 45% had disturbances of liquid and/or solid GE. In less than 5% of the total group both tests were found to be either accelerated or delayed in the same patient. Instead, measurements of liquid and solid GE often differred. In patients with delayed GE in at least one of the tests, severity of gastroparesis symptoms was associated with GE time. Thus, measurements of liquid and solid GE may be complementary and identify patients with different pathomechanism leading to GE disturbances and symptoms.
