Polysomnography-estimated sleep and the negative feedback loop of the hypothalamic-pituitary-adrenal (HPA) axis

Mediating roles of activities of daily living and depression on the relationship between sleep quality and health-related quality of life

This study aimed to explore the mediating effects of ADL and depression on the relationship between sleep quality and HRQOL among older people in rural China, while also exploring the moderating impact of loneliness. The study gathered data from a household survey conducted among 1587 Chinese rural older adults (mean age = 73.63 years). The collected data was analyzed using SPSS version 23.0 software (IBM, New York, USA) and the PROCESS macro version 4.0 program. The findings indicated a significant correlation between sleep quality, ADL, depression, loneliness and HRQOL. ADL and depression exhibited a chain mediation effect on the relationship between sleep quality and HRQOL. Notably, the association between sleep quality and HRQOL was entirely mediated by ADL and depression. Additionally, loneliness acted as a moderator in the relationship between ADL and HRQOL. The findings of this study suggest that interventions focusing on sleep quality should prioritize strategies for enhancing older adults' ADL and depression as integral components of promoting older adults' HRQOL.

Gene‒environment interaction effect of hypothalamic‒pituitary‒adrenal axis gene polymorphisms and job stress on the risk of sleep disturbances

Background

Studies have shown that chronic exposure to job stress may increase the risk of sleep disturbances and that hypothalamic‒pituitary‒adrenal (HPA) axis gene polymorphisms may play an important role in the psychopathologic mechanisms of sleep disturbances. However, the interactions among job stress, gene polymorphisms and sleep disturbances have not been examined from the perspective of the HPA axis. This study aimed to know whether job stress is a risk factor for sleep disturbances and to further explore the effect of the HPA axis gene × job stress interaction on sleep disturbances among railway workers.

Methods

In this cross-sectional study, 671 participants (363 males and 308 females) from the China Railway Fuzhou Branch were included. Sleep disturbances were evaluated with the Pittsburgh Sleep Quality Index (PSQI), and job stress was measured with the Effort-Reward Imbalance scale (ERI). Generalized multivariate dimensionality reduction (GMDR) models were used to assess gene‒environment interactions.

Results

We found a significant positive correlation between job stress and sleep disturbances (P < 0.01). The FKBP5 rs1360780-T and rs4713916-A alleles and the CRHR1 rs110402-G allele were associated with increased sleep disturbance risk, with adjusted ORs (95% CIs) of 1.75 [1.38-2.22], 1.68 [1.30-2.18] and 1.43 [1.09-1.87], respectively. However, the FKBP5 rs9470080-T allele was a protective factor against sleep disturbances, with an OR (95% CI) of 0.65 [0.51-0.83]. GMDR analysis indicated that under job stress, individuals with the FKBP5 rs1368780-CT, rs4713916-GG, and rs9470080-CT genotypes and the CRHR1 rs110402-AA genotype had the greatest risk of sleep disturbances.

Conclusions

Individuals carrying risk alleles who experience job stress may be at increased risk of sleep disturbances. These findings may provide new insights into stress-related sleep disturbances in occupational populations.

The Rotterdam Study. Design update and major findings between 2020 and 2024

The Rotterdam Study is a population-based cohort study, started in 1990 in the district of Ommoord in the city of Rotterdam, the Netherlands, with the aim to describe the prevalence and incidence, unravel the etiology, and identify targets for prediction, prevention or intervention of multifactorial diseases in mid-life and elderly. The study currently includes 17,931 participants (overall response rate 65%), aged 40 years and over, who are examined in-person every 3 to 5 years in a dedicated research facility, and who are followed-up continuously through automated linkage with health care providers, both regionally and nationally. Research within the Rotterdam Study is carried out along two axes. First, research lines are oriented around diseases and clinical conditions, which are reflective of medical specializations. Second, cross-cutting research lines transverse these clinical demarcations allowing for inter- and multidisciplinary research. These research lines generally reflect subdomains within epidemiology. This paper describes recent methodological updates and main findings from each of these research lines. Also, future perspective for coming years highlighted.

Associations between obstructive sleep apnea and painful temporomandibular disorder: a systematic review

The relationship between obstructive sleep apnea (OSA) and diverse types of pain conditions have been proposed. However, no consensus on the relationship between OSA and painful temporomandibular disorders (TMDs) has been established. Therefore, this systematic review has been conducted to review the existing literatures and provide comprehensive synthesis of such literatures about OSA and painful TMDs using the evidence-based methodology. A literature search was conducted using two electronic databases, Scopus, and PubMed. Risk of bias was assessed using the risk-ofbias assessment tool for non-randomized study version 2.0. A total of 158 articles were screened from the initial search and eventually, 5 articles were included in this systematic review. One study adopted both the longitudinal prospective cohort and case-control designs and other 4 articles adopted the cross-sectional design. Two studies employed polysomnography (PSG) for the diagnosis of OSA and mentioned the results from the PSG. All crosssectional studies demonstrated higher OSA prevalence among patients with TMD, and one cohort study suggested OSA as a risk factor for TMD. OSA appears to have potential influences on the development of TMD; however, the role of TMD in the development of OSA remains to be unknown owing to the lack of high-quality evidences.

Potential Role of Obstructive Sleep Apnea on Pain Sensitization and Jaw Function in Temporomandibular Disorder Patients

BACKGROUND

The relationships between obstructive sleep apnea (OSA) and diverse types of pain disorders have been reported. However, the interaction between OSA and pain-related temporomandibular disorder (TMD) remains obscure.

METHODS

A total of 60 adults (male/female, 48/12; mean age, 41.7 ± 13.2 years) with pain-related TMD were enrolled. All participants underwent overnight full-channel polysomnography and had assessment of size and position of the tongue, tonsillar size, height, and weight. Diagnostic Criteria/TMD criteria was applied to diagnose TMD. Myofascial trigger points (TrPs) were bilaterally evaluated in the two masticatory and four cervical muscles including the temporalis, masseter, trapezius, sternocleidomastoid, occipitalis, and splenius capitis muscles. Participants were divided into three groups in accordance with their levels of OSA.

RESULTS

The significantly higher number of active TrPs were detected in participants with severe OSA. The number of active TrPs in the masticatory muscles significantly interacted with diverse types of apneic and arousal indices.

CONCLUSION

The myofascial pain modulating mechanisms and jaw function could have interactions with nocturnal hypoxia and sleep fragmentation in chronic pain-related TMD patients.