Between 2011 and 2016, 5,238 blood samples from 2,707 healthy children and adolescents, aged 0.14 months to 18 years, were collected as part of the German LIFE-Child longitudinal study, which aims to document the development of a healthy child from birth to early adulthood.
- CPK levels rise sharply during the first year of life in both boys and girls, peaking shortly after the age of one.
- It then declines until the age of three, reaching a plateau between the ages of five and nine, with boys’ values higher than girls’.
- From the age of nine onwards, CPK levels begin to diverge: in boys, they rise more sharply at the onset of puberty, reaching 14.48 µkat/L at the age of 18, while in girls, the level is only 5.74 µkat/L.
- The use of oral contraceptives, extreme thinness, thinness or obesity are inversely correlated with CPK levels.
The authors recommend the use of age- and sex-specific reference values when measuring CPK in children and adolescents.
