Associations between perceived stress and cortisol biomarkers in predominantly Latino adolescents

The relationship between cortisol and perceived stress is poorly understood. We sought to determine whether perceived stress is associated with cortisol biomarkers in adolescents. In a sample of 229 adolescents (mean age = 15.8 years) we measured perceived stress with the 14-item Perceived Stress Scale (PSS) questionnaire, serum cortisol (sCOR), salivary Cortisol Awakening Response (CAR: 30-minute post-awakening - awakening), salivary Diurnal Cortisol Slope (DCS: evening-awakening), and total daily salivary cortisol (TDC). Multivariable linear regression was used to estimate baseline associations between PSS, TDC, and sCOR Mixed effects linear regression was used to estimate baseline associations between PSS and CAR and DCS. A twelve-week longitudinal association between PSS and cortisol biomarkers using random effects regression was tested. Analyses were adjusted for age, gender, and BMI. There were statistically significant associations between PSS and TDC (beta= -104.36 ± 34.3; p = 0.002) at baseline and between PSS and DCS at 12 weeks (beta= -0.058 ± 0.02; p = 0.01), but no association between PSS and sCOR or CAR (p > 0.26 for all) at baseline or 12-weeks. There were no associations between change in PSS and change in cortisol biomarkers longitudinally. In adolescents, perceived stress, measured by the PSS, was inconsistently associated with TDC and DCS, and consistently unassociated with CAR and sCOR. Studies reporting on PSS outcomes should exercise caution when making conclusions about cortisol biomarkers. There is a need for greater specificity of psychological stress to understand their relationship with biomarkers of stress.