Gastric emptying in infants with or without gastro-oesophageal reflux according to the type of milk

The present study was designed to determine the effects of milk composition and the influence of gastro-oesophageal reflux (GOR) on gastric emptying. Cineoesogastrocintigraphy (COGS) was performed in 201 infants between 0-1 year of age in order to detect GOR, and provided a means of estimation of the gastric emptying (GE). Ninety infants appeared free from GOR and constituted the control group; 111 had GOR. There infants were fed human milk or various standard formulae. In addition, 20 infants fed a whey-hydrolysate formula were tested. An appropriate volume of milk was marked with sulfur-colloid Tc (200 microcuries). Measurements of gastric radioactivity were made 30 min and 120 min after ingestion. For the whole population, the infants with GOR had slightly more rapid GE after 30 min (P < 0.05), but, for the same type of milk, there was no significant difference between GOR and controls. GE did not differ with age or sex, but differed mainly according to the type of milk. In the control group, gastric residual content (GRC) at 120 min was 18 +/- 11 per cent with human milk (n = 7), 16 +/- 21 per cent with whey-hydrolysate formula (n = 8), 25 +/-17 per cent with acidified formula (n = 13), 26 +/- 19 per cent with whey-predominant formula (n = 22), 39 +/- 17 per cent with casein-predominant formulae (n = 20), 47 +/- 19 per cent with follow-up formulae (n = 16) and 55 +/- 19 per cent with cow's milk (n = 12). Composition of these formulae did not differ by osmolality, caloric density or fat composition. Protein concentration and composition seemed to be the main difference. GE was more rapid with whey-predominant formulae than with casein-predominant formulae, with the exception of acidified cow's milk formula which had a high gastric emptying rate. This study allows us to classify formulae with actions similar to GE-like drugs according to their pharmacokinetic elimination, as rapid formula, slow formulae and very slow formulae.