Does age affect gastric emptying time? A model-based meta-analysis of data from premature neonates through to adults

Area of Science:

• Pediatric Gastroenterology
• Pharmacokinetics
• Neonatal Physiology

Background:

• Gastric emptying (GE) is crucial for nutrient absorption and drug bioavailability.
• Previous assumptions suggested slower and more irregular GE in premature neonates compared to older individuals.
• Understanding GE dynamics is vital for optimizing feeding and medication in infants.

Purpose of the Study:

• To investigate the influence of age and other factors on the rate of gastric emptying.
• To analyze the impact of postnatal age, gestational age, and meal type on gastric residence times.
• To challenge the notion that age is the primary determinant of GE differences in neonates.

Main Methods:

• A meta-analysis of 49 studies involving 1457 individuals, from 28 weeks gestation to adulthood.
• Utilized a nonlinear mixed-effects modeling approach (NONMEM 7.2) to analyze mean gastric residence times (MGRT).
• Employed a double Weibull function to model the biphasic nature of gastric emptying, assessing age and meal type as covariates.

Main Results:

• Age was not found to be a significant covariate influencing gastric emptying rates.
• Meal composition significantly affected GE, with aqueous solutions emptying fastest (45 min MGRT).
• Solid food exhibited the slowest gastric emptying time (98 min MGRT).

Conclusions:

• The study challenges the widely held belief that age is the primary reason for differences in GE between neonates and older populations.
• Findings highlight the critical role of meal type in modulating gastric emptying dynamics across different age groups.
• This research provides a more nuanced understanding of GE, emphasizing food composition over age as a key determinant.