Change in Salivary Cortisol Levels in Children (Aged 9–12 Years) with Obesity and Respiratory Diseases during a 28-Day Spa Treatment: A Pilot Prospective Study

This study aimed to examine the impact of a 28-day structured spa treatment on salivary cortisol levels in children aged 9–12 years diagnosed with obesity or chronic respiratory diseases. The study included 95 children at spas and 38 children from a primary school (control group). Laboratory analyses were performed at the Institute of Endocrinology in Prague. In children with obesity (n = 34), a decrease in mean cortisol levels from 3.32 to 2.36 nmol/l was observed. In children with respiratory diseases not receiving corticosteroid therapy (n = 18), cortisol levels increased from 2.68 to 3.48 nmol/l. The control group showed an increase from 3.52 to 4.02 nmol/l (n = 38). These findings highlight the relevance of salivary cortisol as a dynamic stress biomarker for pediatric rehabilitation research. The findings support the utility of salivary cortisol as a biomarker of physiological response to therapeutic and rehabilitative interventions in pediatric populations.