Long-term stability of the cortisol awakening response over adolescence

This is the first study, in a large population based sample, indicating that the rank-order of the CAR is stable over the course of several years. Interestingly, mean-levels of the cortisol response to awakening increased over the years, suggesting a maturation of HPA axis reactivity in relation to physical development over adolescence. Physical development should therefore be taken into account when investigating the CAR as a measure of HPA axis activity in adolescence.