Caregivers’ hair cortisol: a possible biomarker of chronic stress is associated with obesity measures among children with disabilities

Table 4 Linear regression models for the associations between caregiver hair cortisol concentrations and child obesity measures

Child obesity measures	Beta (standard error)	P value	R-square	Adjusted R-square
Unadjusted models
Weight (kg)	4.86 (2.10)	0.023	0.06	0.05
Body mass index (kg/m²)	1.53 (0.72)	0.037	0.05	0.04
Neck circumference (cm)	1.43 (0.47)	0.003	0.10	0.09
Waist circumference (cm)	4.03 (1.50)	0.009	0.08	0.07
Hip circumference (cm)	3.32 (1.57)	0.037	0.05	0.04
Waist-to-hip ratio	0.01 (0.01)	0.193	0.02	0.01
Body fat percentage (%)	1.87 (1.40)	0.188	0.03	0.01
Child age and sex adjusted models
Weight (kg)	4.47 (2.09)	0.036	0.10	0.07
Body mass index (kg/m²)	1.52 (0.71)	0.035	0.12	0.09
Neck circumference (cm)	1.20 (0.43)	0.006	0.29	0.26
Waist circumference (cm)	3.75 (1.50)	0.014	0.12	0.09
Hip circumference (cm)	3.02 (1.48)	0.044	0.19	0.16
Waist-to-hip ratio	0.01 (0.01)	0.191	0.13	0.09
Body fat percentage (%)	2.11 (1.28)	0.104	0.22	0.19
Child age, sex, and disability diagnosis and caregiver age, sex, education, smoking, and perceived stress adjusted models
Weight (kg)	4.73 (1.96)	0.018	0.37	0.27
Body mass index (kg/m²)	1.56 (0.72)	0.033	0.29	0.17
Neck circumference (cm)	0.98 (0.44)	0.029	0.40	0.30
Waist circumference (cm)	3.74 (1.60)	0.023	0.19	0.06
Hip circumference (cm)	2.98 (1.54)	0.057	0.30	0.18
Waist-to-hip ratio	0.01 (0.01)	0.198	0.22	0.09
Body fat percentage (%)	1.89 (1.37)	0.175	0.34	0.20

Caregiver hair cortisol concentrations were log-transformed and considered as an exposure variable, while child obesity measures served as outcome variables in the models.