Hair cortisol and self-perceived stress in adolescents with multi-system functional somatic disorders

BMC Psychiatry

Table 2 Comparison of hair cortisol concentrations between AHEAD and CCC2000 (whole sample and subgroup with a high physical symptom load) using multiple linear regression

Model	Dependent variable: HCC^a
Model	β	95%CI	P
CCC2000 compared with AHEAD
Crude
CCC2000 (n = 1,450)	1 (ref.)
AHEAD (n = 91)	1.05	0.88; 1.24	0.590
Adjusted for sex, age and BMI^a
CCC2000 (n = ^b)	1 (ref.)
AHEAD^c (n = 91)	0.80	0.66; 0.97	0.023*
CCC2000 subgroup with a high physical symptom load compared with AHEAD
Crude
CCC2000 subgroup (n = 147)	1 (ref.)
AHEAD (n = 91)	0.97	0.79; 1.20	0.786
Adjusted for sex, age and BMI^a
CCC2000 subgroup (n = 147)	1 (ref.)
AHEAD^d (n = 91)	0.84	0.66; 1.07	0.156

AHEAD Acceptance and Commitment Therapy for Health in Adolescents, BMI Body Mass Index, CCC2000 Copenhagen Child Cohort 2000, CI confidence interval, HCC hair cortisol concentration, n number in specific population, ref. reference group
^aHCC and BMI were log-transformed for analyses; the table presents the back-transformed values
^bDue to missing covariate data in CCC2000, ≤ 5 persons were excluded in the adjusted analysis
^cInterpretation (adjusted analysis comparing the CCC2000 total sample to AHEAD): if two persons from CCC2000 and AHEAD with the same sex, age and BMI are compared with each other, the person from AHEAD will have a 20% (95%CI: 3%, 34%) lower median HCC than the person from CCC2000. For example, the median HCC in a 17-year-old girl from AHEAD with BMI 21 will be 1.9 (95%CI: 1.6, 2.2) pg/mg, whereas the median HCC in an equivalent participant from CCC2000 will be 2.3 (95%CI: 2.2, 2.5) pg/mg
^dInterpretation (adjusted analysis comparing the CCC2000 subgroup to AHEAD): if two persons from the CCC2000 subgroup and AHEAD with the same sex, age and BMI are compared with each other, the person from AHEAD will have a 16% (95%CI: -7%, 34%) lower median HCC than the person from the CCC2000 subgroup
^* p < 0.05

ISSN: 1471-244X