Plasma irisin associations with executive function among children in a prospective cohort.

OBJECTIVE: To examine the longitudinal associations between irisin and executive function among children, as well as the sex difference in this correlation. METHODS: The study involving 330 children aged 6-10 years conducted in Guangzhou, China. Baseline surveys and fasting blood samples were collected in 2017. Plasma irisin concentration was measured using Enzyme-Linked Immunosorbent Assay (ELISA). Executive function was assessed by the Behavior Rating Inventory of Executive Function (BRIEF) scale in 2017 and followed up after 2 years. Multivariable linear regression was used for association analysis. RESULTS: The plasma irisin concentration was 9.04±2.18 ng/mL. There was no statistical difference in plasma irisin and change values of BRIEF T-scores between boys and girls. No significant associations were found between plasma irisin and change values of BRIEF T-scores (P > 0.05) in the overall sample. Further subgroup analyses according to sex revealed that plasma irisin was negatively associated with change values of behavior regulation index (BRI, ß=-0.521, 95 %CI: -1.036 ∼ -0.006), emotional control (ß=-0.649, 95 %CI: -1.249 ∼ -0.049), working memory T-scores (ß=-0.774, 95 %CI: -1.350 ∼ -0.199) in girls. Moreover, we firstly identified a sex effect modification in the association of plasma irisin with change values of working memory T-score (Pinterference=0.012). CONCLUSIONS: Higher irisin concentration was associated with better executive function performance in girls. Further studies that included populations in other regions or countries are needed to confirm these findings.