The study findings published in the journal 'Scientific Reports' also suggest that the unique makeup of the microbiome in infants with growth failure might contribute to their inability to properly metabolize nutrients thus affecting their overall health.
"Our identification of the distinct features within the microbiome and metabolism associated with growth failure might point to new ways to predict, prevent and treat this pervasive problem among preterm infants," says one of the senior authors Patrick Seed
The human microbiome is estimated to have over a trillion bacteria in a single person, with 10 times the number of microbial cells to every human cell. Specific microbiome characteristics play causal roles in obesity, allergy, asthma, diabetes, autoimmune disease, depression and a variety of cancers.
"In our study, we investigated the relationships between intestinal microbiome, metabolism and growth in preterm infants," said Dr. Seed.
Growth failure in preterm infants is a risk factor for cognitive and motor impairment and may predispose these children to obesity, type-2 diabetes and heart disease later in life.
The study included 58 infants who were born at or before 27 weeks of pregnancy, weighing less than two pounds on average. Growth failure in these infants was defined as weight less than the third percentile on sex-specific growth charts at 40 weeks of postmenstrual age (birth gestational age plus chronological age).
Out of the 58 babies, 36 had growth failure, while the rest had appropriate growth.
Infants with growth failure had a disrupted maturation of the intestinal microbiome, characterized by low bacterial diversity, the dominance of certain disease-causing bacteria (Staphylococcus and Enterobacteriaceae) and low proportions of harmless bacteria (such as Veillonella).
They also depicted delayed metabolic development with features that suggest deficiencies in the metabolism of glucose and other non-lipid fuels, leading to greater reliance on fatty acids.
"Our analyses of the relationship between the microbiome of infants with growth failure and the byproducts of their metabolism suggest that the unique composition of bacterial communities living in their gut might play a role in this metabolic state with similarities to fasting," added Dr. Seed.
"This might explain why simply increasing calorie supply for infants with growth failure often does not work," added Dr Seed.