Biological maturation and sex differences of cholinergic sweating in prepubertal children to young adults

Compared to adults, prepubertal children exhibit underdeveloped cholinergic sweating. How maturation affects cholinergic sweating through early adulthood remains unclear. We assessed the influence of age and sex on cholinergic sweating, including seasonal acclimatization, in groups of prepubescent to young adult males and females. A total of 405 children and adolescents (ages 6-17; 229 boys and 176 girls) and 52 young adults (ages 18-25; 25 males and 27 females) underwent pilocarpine iontophoresis on the ventral forearm to induce cholinergic sweating during summer (n = 111) and non-summer (n = 457). Sweat gland output, calculated as sweat rate divided by activated sweat gland density, was compared between sexes and across age groups in 2-year intervals until age 17. We observed statistically significant sex-related differences in sweat gland output in children as young as 8-9 years of age, with even greater differences between sexes in groups 14-15 years of age and older. The changes in cholinergic sweating function occurred independently of maturational changes in body morphology. Our results offer insight into the sex differences in cholinergic sweating activity during maturation from childhood to adolescence.