Stress reactivity in salivary cortisol and electrocardiogram in adolescents: Investigating sleep disturbances and insomnia

Exposure to diesel-related particulate matter, cortisol stress responsivity, and depressive symptoms in adolescents

Exposure to air pollution is associated with higher risk for psychopathology; however, the mechanisms underlying this association are not clear. Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis in response to stress has been implicated in depression. Here, we estimated annual exposure to particulate matter (PM) from diesel emissions in 170 9- to 15-year-old adolescents (56 % female) using their residential addresses and data from nearby monitoring sites. We obtained salivary cortisol samples from participants while they completed a social stress task and calculated area under the curve with respect to ground (AUCg) and with respect to increase (AUCi) in order to assess cortisol responsivity during stress. Participants also reported on their depressive symptoms and sleep disturbances. Greater exposure to diesel PM was associated with lower cortisol output (AUCg) during stress, which was associated with higher depressive symptoms, particularly for adolescents with more sleep disturbances. Importantly, these effects were independent of household and neighborhood socioeconomic disadvantage and exposure to early adversity. Thus, HPA-axis dysfunction may be one mechanism through which environmental pollutants affect adolescents' mental health.

Predicting response to stepped-care cognitive behavioral therapy for insomnia using pre-treatment heart rate variability in cancer patients

OBJECTIVE

This study examined whether high frequency heart-rate variability (HF-HRV) and HF-HRV reactivity to worry moderate response to cognitive behavioural therapy for insomnia (CBT-I) within both a standard and stepped-care framework among cancer patients with comorbid insomnia. Biomarkers such as HF-HRV may predict response to CBT-I, a finding which could potentially inform patient allocation to different treatment intensities within a stepped-care framework.

METHODS

177 participants (86.3 % female; Mage = 55.3, SD = 10.4) were randomized to receive either stepped-care or standard CBT-I. 145 participants had their HRV assessed at pre-treatment during a rest and worry period. Insomnia symptoms were assessed using the Insomnia Severity Index (ISI) and daily sleep diary across five timepoints from pre-treatment to a 12-month post-treatment follow-up.

RESULTS

Resting HF-HRV was significantly associated with pre-treatment sleep efficiency and sleep onset latency but not ISI score. However, resting HF-HRV did not predict overall changes in insomnia across treatment and follow-up. Similarly, resting HF-HRV did not differentially predict changes in sleep diary parameters across standard or stepped-care groups. HRV reactivity was not related to any of the assessed outcome measures in both cross-sectional and longitudinal analyses.

CONCLUSION

Although resting HF-HRV was related to initial daily sleep parameters, HF-HRV measures did not significantly predict longitudinal responses to CBT-I. These findings suggest that HF-HRV does not predict treatment responsiveness to CBT-I interventions of different intensity in cancer patients.

Crisis of Faith and Sleep Quality in the United States: A Literal Dark Night of the Soul?

A crisis of faith is an intrapersonal struggle with ultimate meaning that occurs when one's supramundane reality is called in question. We propose a theoretical model which suggests that a crisis of faith will contribute to poorer sleep quality by undermining a general sense of meaning and purpose in life, especially among women. We use national survey data from the Wave 5 of the Baylor Religion Survey United States (N = 1395). Ordinary least squares regression models with robust standard errors are utilized. Sobel-Goodman mediation techniques are used to test the proposed mediating pathway. Our results suggest that a crisis of faith is associated with lower sleep quality, and that this pathway is partially mediated by a lower sense of meaning and purpose in life. Finally, we found that the relationship between a crisis of faith and lower sleep quality was weaker for women. We discuss the implications of our results and suggest how future research may explore the relevance of a crisis of faith for well-being as well as other aspects of the human condition.

Individualized approaches to pediatric chronic insomnia: Advancing precision medicine in sleep disorders

The manifestations of chronic insomnia undergo age-related changes. In younger infants and children, behavioral insomnia emerges as the most prevalent form and typically responds to behavioral interventions. However, distinct clusters of clinical presentations suggest the presence of various phenotypes, potentially implicating the primary involvement of specific neurotransmitters. These conceptualizations, coupled with genetic studies on pleiotropy and polygenicity, may aid in identifying individuals at risk of persistent insomnia into adulthood and shed light on novel treatment options. In school-age children, the predominant presentation is sleep-onset insomnia, often linked with nighttime fears, anxiety symptoms, poor sleep hygiene, limit-setting issues, and inadequate sleep duration. The manifestations of insomnia in adolescence correlate with the profound changes occurring in sleep architecture, circadian rhythms, and homeostatic processes. The primary symptoms during adolescence include delayed sleep onset, sleep misperception, persistent negative thoughts about sleep, and physiological hyperarousal-paralleling features observed in adult insomnia. An approach centered on distinct presentations may provide a framework for precision-based treatment options. Enhanced comprehension of insomnia's manifestations across diverse developmental stages can facilitate accurate assessment. Efforts to subtype insomnia in childhood align with this objective, potentially guiding the selection of appropriate treatments tailored to individual neurobiological, clinical, and familial features.

Stress, hypothalamic pituitary adrenal axis activity and autonomic nervous system function in adolescents with insomnia

INTRODUCTION

Abnormal stress responses have been linked to the etiology of insomnia. We investigated the relationship between insomnia, stress, hypothalamic-pituitary-adrenal (HPA) axis activity, and autonomic nervous system (ANS) function in adolescence.

METHODS

Forty-seven post-pubertal adolescents (16-20 years old, 28 female) with (N = 16; insomnia group) and without (N = 31; control group) DSM-5 insomnia symptoms were assessed for stress levels and stress reactivity and underwent a standardized stress protocol (Trier Social Stress Test (TSST)), after an overnight laboratory stay. Cortisol was measured upon awakening and 30-minutes later to calculate the cortisol awakening response (CAR). During the TSST, perceived stress, salivary cortisol (HPA activity), heart rate (HR) and blood pressure (BP) measures were collected.

RESULTS

Participants in the insomnia group reported more stress from school performance and work overload, with insomnia girls experiencing more stress from peer pressure and future uncertainty than control girls (p < 0.05). No group differences were detected in the CAR and pre-TSST stress levels. All participants showed significant increases in perceived stress (~19 %), HR (~33 %), systolic (~13 %), and diastolic (~15 %) BP in response to the TSST (p < 0.05). Overall HR stress response did not differ between groups, but was lower in boys with insomnia than in girls with insomnia (p < 0.05). Cortisol stress responses were inconclusive, possibly due to a masking effect of CAR, as the task was performed shortly after awakening and larger CARs were associated with blunted cortisol stress responses.

DISCUSSION

Results mostly show no group difference in physiological stress responses, although some interaction effects suggest a potential sex by insomnia interaction. Larger samples are needed to understand the physiological disturbances of insomnia in adolescence.

The nature, consequences, mechanisms, and management of sleep disturbances in individuals at-risk for psychosis

There is strong evidence that sleep disturbances are commonly experienced by people with psychosis. Evidence has also shown that sleep disturbances are present since the very early stages of the disease, even during the pre-diagnostic phase. More recently, research involving young individuals at ultra-high risk (UHR) for psychosis documented frequent occurrence of sleep disturbances in this group. The very early onset of sleep disturbances in the course of psychosis has drawn attention to the possible links between sleep parameters and the risk of psychosis. To date, the nature of sleep disturbances characterizing the UHR stage remains unclear, with available studies having yielded mixed findings. In this regard, we performed this review to update the body of literature on the nature of sleep disturbances, their underlying mechanisms, their clinical and functional consequences, the prevention and intervention strategies in the at-risk for psychosis population. Our findings provided further support to the presence of disturbed sleep in UHR individuals as evidenced by subjective and objective sleep measures such as polysomnography, sleep electroencephalograms, and actigraphy. Reviewing the possible mechanisms underlying the relationship between sleep and psychosis emphasized its complex and multifactorial nature which is yet to be determined and understood. Further research is warranted to determine which facets of sleep disturbances are most detrimental to this specific population, and to what extent they can be causal factors or markers of psychosis.