Background Emerging evidence supports the importance of physical activity (PA) and behaviours that build resilience to prevent childhood psychiatric disorders. Objective To investigate associations between parent-reported PA, time spent outdoors and participation in organised sports and later incidence of psychiatric conditions in children. Methods A birth cohort of 17 055 Swedish children was followed up until age 18 years. Data on parent-reported PA, time outdoors and participation in organised sports were collected for children at ages 5, 8 and 11. Diagnoses of psychiatric conditions were obtained from a national registry. Longitudinal interactions were analysed with two-way analysis of variance, and hazard ratios for incidence until 18 years were calculated with Cox proportional hazard models, adjusting for mothers’ education and use of psychotropics, children’s adverse life events and sex. Results PA declined from 4.2 to 2.5 hours per day between 5 and 11 years of age. PA at 11 years was negatively associated with the incidence of any psychiatric conditions among all participants (HR=0.88, 95% CI 0.79 to 0.98) until 18 years. PA at 11 years showed a trend for reducing depression among girls (HR=0.82, 95% CI 0.67 to 1.00) and boys (HR=0.71, 95% CI 0.47 to 1.06) and protected against anxiety (HR=0.61, 95% CI 0.42 to 0.90) and addiction (HR=0.65, 95% CI 0.45 to 0.95) for boys, but not for girls (anxiety: HR=0.96, 95% CI 0.81 to 1.13, addiction: HR=1.04, 95% CI 0.68 to 1.58). Time outdoors showed no protective associations, while participation in organised sports showed significant protective effects on anxiety and addiction for both boys and girls, and on depression for boys. Conclusions This study provides evidence that PA and participation in organised sports may have sex-specific protective effects against several childhood psychiatric conditions.

Cortisol in hair is a new biomarker assessing long-term hypothalamic-pituitary-adrenal (HPA) axis activity, which is related to emotion regulation. We compare hair cortisol concentrations (HCC), in clinically referred children with disruptive mood dysregulation disorder (DMDD) (n = 19), children with other types of psychological disorders (n = 48), and healthy subjects (n = 36). We also investigate the association between HCC and irritability, age, and sex. Our results show that children with DMDD or other types of psychological disorders have higher HCC than healthy subjects, p < .001, η_p² = .39. No difference between children with DMDD and those with other types of psychological disorders was found, p = .91, nor an association between HCC and irritability in the clinical sample, p = .32. We found a significant negative correlation between HCC and age in those with DMDD, r = -0.54, p < .05, but not in the normative sample, r = -0.20, p = .25. No differences in HCC between girls and boys were found in the normative sample, p = .49. Children in need of psychological treatment, including those with DMDD, seem to have dysregulated HPA-axis activity over time. Excessive accumulated cortisol concentrations in hair could be an indicator of a psychological disorder in children.

Background/Objectives: The vagus nerve is a key neurophysiological pathway connecting the brain and body. Its functional state—vagal tone—is typically indexed by heart-rate variability (HRV) and inversely reflects physiological stress. Adolescents often exhibit reduced vagal tone and heightened stress reactivity. Schools offer a strategic setting for delivering stress-reduction interventions. This pilot study assessed the feasibility, safety, and preliminary efficacy of a school-based program combining HRV biofeedback with transcutaneous auricular vagus nerve stimulation (taVNS). Methods : Seventeen Vocational Education and Training (VET) students (ages 15–17) from AZITAIN-IFMPB (Eibar, Spain) completed six weekly 30-minute sessions. Each session included paced-breathing biofeedback (emWave®) combined with taVNS (Parasym™). Feasibility was assessed via recruitment, retention, acceptability, and adverse events. Physiological outcomes included HRV (analysed with Kubios) and hair cortisol concentration. State anxiety was assessed using the State–Trait Anxiety Inventory (STAI). Assessments were conducted at baseline, post-intervention, and at 7-week follow-up . Results: Recruitment reached 50%; retention in the second cohort was 75%. The intervention was well tolerated, with 80% acceptability and one mild adverse event. taVNS significantly increased parasympathetic activity (PNS index; F(1, 11) = 5.26, p = .043, η ² _p = 0.32), and reduced state anxiety (STAI; F(1, 13) = 6.79, p = .022, η ² _p = 0.34). Hair cortisol rose post-intervention (F(1, 12) = 11.75, p = .005, η ² _p = 0.49), but declined below baseline at follow-up. Conclusions : This pilot study demonstrated the feasibility of implementing the intervention in adolescents and provided preliminary estimates of its effects on stress-related outcomes, which will inform the design of a larger, controlled trial.

Background: Chronic stress exposure has been linked to cardiovascular risk factors and cardiovascular diseases, but not to coronary artery calcification (CAC). Hair cortisol concentrations is a potential biomarker of chronic stress. Atherosclerosis is the predominant cardiovascular disease and the leading cause of death in developed countries. Coronary artery calcification is a sign of atherosclerosis in the coronary arteries and predicts coronary heart disease. Most men and women are to some degree affected by coronary artery calcification at the age of 65. Objectives: To analyse if increased hair cortisol levels are associated with CAC in a middle-aged population with special focus on women. Further, to analyse the relative importance of HCC for CACs in relation to established cardiovascular risk factors. Methods: Hair samples, cardiac computed tomography data, health questionnaires, and anthropometric measures were collected in 4821 men and women aged 50-65 years, from the Swedish Cardio Pulmonary bioImage Study. A competitive radioimmunoassay was used to analyze cortisol levels in extracts of hair. Correlation, descriptive, regression and path analyses were applied. Results: A significant association between high HCC and high CAC score was found among women (p=0.007), but not among men. HCC was significantly directly associated with a higher CAC score among women, as were the other classical cardiovascular risk factors. Conclusion: The amount of calcified plaque (CAC score) in the coronary arteries of women was significantly associated with higher cortisol levels in hair, while this association was not observed in men.