Li N, Arbuckle TE, Muckle G, Lanphear BP, Boivin M, Chen A, Dodds L, Fraser WD, Ouellet E, Séguin JR, Velez MP, Yolton K, Braun JM. Psychoneuroendocrinology. 2018 Oct 25;99:257-264. doi: 10.1016/j.psyneuen.2018.10.021.
Adiponectin is a hormone that increases insulin sensitivity and helps regulate glucose metabolism. Leptin is a hormone responsible for the regulation of food intake, with higher blood levels reducing hunger and increasing energy use. These metabolic hormones may play a role in child neurodevelopment. The objective of this study was to see whether the levels of these hormones in umbilical cord blood are associated with the child’s IQ later in life.
Data from two studies, the Canadian MIREC (Maternal-Infant Research on Environmental Chemicals) and American HOME (Health Outcomes and Measures of the Environment) studies were used to investigate this research question. Mothers and their infants were included in this analysis, 429 from MIREC and 183 from HOME. Leptin and adiponectin were measured in umbilical cord blood samples and the child’s IQ was measured when the child was 3-8 years of age.
After adjusting for various factors, the study found that higher cord blood adiponectin levels were associated with higher IQ scores in the children at age 3 in MIREC and at ages 5 and 8 years in the HOME study. The hormone leptin was not associated with child IQ in either study.
Future studies are needed to explore why adiponectin levels in cord blood may be associated with a child’s IQ.