The School-Ladder Effect: Subjective Socioeconomic Status and Diurnal Cortisol Profile Among Adolescents

Subjective socioeconomic status (SES) is a well-established psychosocial determinant of adolescents' self-report health. However, whether low subjective SES is associated with stress-related physiological risks (e.g., dysregulations in the hypothalamic-pituitary-adrenal axis activity) remains uncertain. This study examined the impact of subjective SES with different reference groups (i.e., perception of family SES relative to other students in the school versus other people in the city) on adolescents' diurnal cortisol profiles.

A sample of 255 adolescents (aged 11-14 years; 53.7% boys) completed a battery of psychological scales, including school-referenced subjective SES and city-referenced subjective SES. Diurnal cortisol was assessed by collecting saliva samples four times a day across two consecutive days. Four cortisol parameters (cortisol at awakening, cortisol awakening response [CAR], cortisol slope, and total cortisol secretion [area under the curve with respect to ground {AUCg}]) were derived.

Higher levels of school-referenced subjective SES were associated with higher cortisol levels at awakening (β = 0.0483, standard error [SE] = 0.0219, p = .028), steeper cortisol slopes (β = -0.0036, SE = 0.0017, p = .034), and higher cortisol AUCg (b = 0.50, SE = 0.24, p = .036), but not with CAR (p = .77), after adjusting for covariates. In contrast, city-referenced subjective SES was not associated with any of the cortisol parameters (cortisol at awakening [p = .90], CAR [p = .74], cortisol slope [p = .84], and cortisol AUCg [p = .68]).

Our findings highlight the importance of the reference group for subjective SES and provide a further understanding of socioeconomic disparities in adolescents' stress physiology.