Fig. 3: The interaction of overweight/obesity with age-associated circulating proteins.

PLS-DA score plot showing plasma protein profiles across three age groups in children and adolescents with a overweight/obesity and b normal weight. c Associations between age and top 26 proteins with significant age × overweight/obesity interactions (FDR P < 1.0E-04). Linear regression models included an interaction term for age × overweight/obesity, adjusted for sex. β-coefficients (center) with 95% CIs (error bars) are shown separately for the overweight/obesity (light blue; n = 2377) and normal weight (brown; 1647) groups. d Box plots of the NPX levels for the four proteins with the largest age-related differences between overweight/obesity and normal weight, visualized across the three age groups. In box plots, the center line represents the median, the bounds of the box indicate the interquartile range (IQR), and the whiskers represent the minimum and maximum values within 1.5 × IQR. Comparisons between overweight/obesity and normal weight groups within each age group were performed using two-sided t-tests. Exact P values are: OSM: age group 1, P = 0.63; age group 2, P = 1.65E-46; age group 3, P = 4.00E-24. LEP: age group 1, P = 3.87E-194; age group 2, P = 1.31 E-296; age group 3, P = 1.44E-64. IL1ra: age group 1, P = 2.72E-93; age group 2, P = 2.42E-277; age group 3, P = 6.63E-76. HGF: age group 1, P = 1.02E-11; age group 2, P = 5.80E-59; age group 3, P = 5.86E-28. Three asterisks (***) indicate a significant difference between groups (P < 0.001); ns not significant. Sample sizes: n = 586, 1435, and 343 for age groups 1, 2, and 3 in the overweight/obesity group; and n = 486, 863, and 294 for age groups 1, 2, and 3 in the normal weight groups, respectively. Source data are provided as a Source data file.