Effect of Birth Weight and Rapid Weight Gain During Infancy on Insulin Sensitivity

Higher birth weight and faster gain of childhood adipose tissue before the age of 2 decreased insulin sensitivity and increased insulin resistance in early adolescence, according to a study published in the Journal of Clinical Endocrinology and Metabolism.

Researchers evaluated children aged 8 to 10 years with both biological parents of with at least 1 parent who was obese.  There were 630 families who participated in a clinical visit at baseline and 2 years later, where they had physical and physiological measurements, and completed health-related questionnaires.  They also analyzed birth anthropometric measurements.  Body composition by dual-energy X-ray absorptiometry was done in children aged 9 to 10 years and childhood adiposity was assessed.  All children underwent a 2-hour oral glucose tolerance test and their physical activity was assessed for a 7-day period when they were aged 10 to 12 years.

At baseline, 54% of the children were normal weight, 22% were overweight, and 24% were obese. At birth, 7% were small for gestational age, and 13% were large for gestational age.  Childhood adiposity mediates the association between weight-for-length score at birth and insulin sensitivity. An increase of one unit of weight-for-length resulted in an 4.74% increase in insulin resistance (95% CI, 1.13-8.41) and a 4.44% decrease of insulin sensitivity (95% CI, -7.91 to -1.05) if the child had excessive adipose weight gain before the age of 2, or an increase of one unit of weight-for-length resulted in an 6.81% decrease in insulin resistance (95% CI, -11.89 to -1.87) and a 9.99% increase in insulin sensitivity (95% CI, 5.26-14.85) if the child remained in projected growth centiles. Babies with low birth weight, babies with high birth weight, and babies who gain weight quickly are all at risk for glucose-related complications during adolescence.

Future studies need to collect birth anthropometric measurements for research purposes, include a greater number of babies born small for gestational age, analyze nutritional intake during infancy, and evaluate maternal weight changes with pregnancy.

In conclusion, birth weight and weight gain during the first 2 years of life can set a child up for future metabolic complications based on the development of adipose tissue. Investigators added that, “children with a lower birth weight should be monitored for metabolic complications, as should children with a higher birth weight or with a higher rate of weight gain early in life that is followed with excess gain in adiposity during childhood. These efforts may contribute to the prevention of childhood obesity and its deleterious metabolic consequences.”

This study was supported by the Canadian Institutes of Health Research, the Heart and Stroke Foundation of Canada, and the Fonds de la Recherche du Québec – Santé. Please refer to reference for a complete list of authors’ disclosures.

Reference

Van Hulst A, Paradis G, Benedetti A, Bernett TA, Henderson M. Pathways linking birth weight and insulin sensitivity in early adolescence: a double mediation analysis [published online August 21, 2018]. J Clin Endocrinol Metab. doi: 10.1210/jc.2018-00525