Gastric emptying time is faster in cystic fibrosis

The high energy requirements in cystic fibrosis (CF) increase the likelihood of malnutrition. Delayed mouth-to-cecum transit times have been reported and raise the possibility that abnormalities of gastric function in CF contribute to reduced food intake. The aims of this project were to document solid-phase gastric emptying times in young people with CF and age- and sex-matched healthy controls, and to investigate whether delayed gastric emptying contributes to suboptimal energy intakes.

Nineteen subjects with CF, mean age 12.6 years (11 girls and 8 boys), and 17 control subjects, mean age 12.8 years (9 girls and 8 boys), were studied. Energy intake was assessed by means of a 4-day weighed food record. Fecal fat excretion was determined from a 3-day stool collection. Gastric emptying was assessed with a standard test meal of pancakes labeled with 99mTc-macroalbumin aggregates. The half emptying time of solids from the stomach was recorded.

The mean solid-phase gastric emptying time was significantly faster in the CF subjects compared with normal, healthy, age- and sex-matched control subjects (53 min vs. 72.2 min, p < 0.05). Energy intakes, measured as the percentage of the recommended energy intake for age and sex, were greater in the CF subjects than in the control subjects (115% vs. 89%, p < 0.01), whereas the mean % FFE for the CF subjects was 9.9%. CF subjects with longer gastric emptying times also had lower relative energy intakes (r = -0.50, p < 0.05).

Gastric emptying time in healthy subjects with CF is rapid. Faster solid-phase gastric emptying times may be secondary to high-fat, high-energy intakes and may represent a survival advantage.