Alterations in Rev-ERBα/BMAL1 ratio and glycated hemoglobin in rotating shift workers: the EuRhythDia study

Transcriptional dynamics in type 2 diabetes progression is linked with circadian, thermogenic, and cellular stress in human adipose tissue

The prevalence of type 2 diabetes (T2D) has increased significantly over the past three decades, with an estimated 30-40% of cases remaining undiagnosed. Brown and beige adipose tissues are known for their remarkable catabolic capacity, and their ability to diminish blood glucose plasma concentration. Beige adipose tissue can be differentiated from adipose-derived stem cells or through transdifferentiation from white adipocytes. However, the impact of T2D progression on beige adipocytes' functional capacity remains unclear. Transcriptomic profiling of subcutaneous adipose tissue biopsies from healthy normal-weight, obese, prediabetic obese, and obese subjects diagnosed with T2D, reveals a progressive alteration in cellular processes associated with catabolic metabolism, circadian rhythms, thermogenesis-related signaling pathways, cellular stress, and inflammation. MAX is a potential transcription factor that links inflammation with the circadian clock and thermogenesis during the progression of T2D. This study unveils an unrecognized transcriptional circuit that increasingly disrupts subcutaneous adipose tissue oxidative capacity during the progression of T2D. These findings could open new research venues for developing chrono-pharmaceutical strategies to treat and prevent T2D.

The association between insomnia (related symptoms) and glycaemic control: a systematic review and meta-analysis

Background

Insomnia characterised by difficulties in falling asleep and maintaining sleep, and early awaking, is a prevalent worldwide sleep disorder. While previous studies have suggested an association between insomnia and adverse glycaemic control, the evidence remains inconclusive. Therefore, this meta-analysis aims to explore this association.

Methods

Insomnia was assessed based on defined criteria, including related symptoms such as poor sleep quality and low sleep efficiency. Glycaemic control was evaluated using indicators such as fasting plasma glucose, haemoglobin A1c, and the presence of diabetes. A literature search was performed in PubMed, Web of Science, and Scopus. The quality of the included studied was assessed using The Newcastle-Ottawa Scale. Effect sizes, including odds ratio, relative risk, mean difference, and standard mean difference, were chosen based on data type. Forest plots visually displayed pooled effect sizes and corresponding 95% confidence intervals, while the I2 test calculated heterogeneity. Meta-regression and subgroup analysis explored potential sources of heterogeneity. Leave-one-out sensitivity analysis assessed result robustness, and Begg's and Egger's tests evaluated publication bias.

Results

Ninety-one articles, comprising 84 are cross-sectional studies, (five are case-control studies, and two are cohort studies) with 2 217 521 participants, were included. Ten separate meta-analyses were conducted based on variable type (binary/continuous), study design (cross-sectional, case-control, or cohort), and measurement of exposures/outcomes. All meta-analyses indicated a positive association between insomnia (related symptoms) and adverse glycaemic control. However, three meta-analyses showed significant heterogeneity, and three lacked robustness. No publication bias was detected across any of the analyses.

Conclusions

Insomnia is likely associated with adverse glycaemic control. As the included studies are observational, future research should prioritise diverse methodologies and robust study designs to further explore this complex relationship.

Keywords

insomnia, insomnia related symptoms, glycaemic control, systematic review, meta-analysis.

Registration

PROSPERO CRD42024491688.

Transcutaneous auricular vagal nerve stimulation modulates blood glucose in ZDF rats via intestinal melatonin receptors and melatonin secretion

Background

Melatonin (MLT) and its receptor deficiency have been shown to be associated with type 2 diabetes mellitus (T2DM). Transcutaneous auricular vagus nerve stimulation (taVNS) is a non-invasive alternative intervention for patients suffering from hyperglycemia. Here, we aimed to investigate the role of taVNS on blood glucose modulation via intestinal melatonin receptors (MRs) and MLT secretion in hyperglycemia.

Methods

Adult male Zucker diabetes fatty (ZDF) rats and Zucker lean (ZL) littermates were used. Forty ZDF rats were randomized into ZDF, taVNS, Px + taVNS and Lu + Px + taVNS groups (Px: pinealectomy, Lu: Luzindole). ZL rats served as a control group for comparison with ZDF rats without involvement in the taVNS intervention. Thirty min-taVNS interventions (2/15 Hz, 2 mA, 30 min/days) were administered once daily under anesthesia for 3 consecutive weeks in taVNS, Px + taVNS and Lu + Px + taVNS groups. Body weight and fasting blood glucose (FBG) were measured weekly in all rats, and real-time blood glucose was tested in the ZL and ZDF groups before, during and after the taVNS intervention. Plasma MLT concentration and the expression of MRs in the duodenum, jejunum and ileum were measured by the end of experiments.

Results

Compared with the ZL group, the level of FBG and body weight increased (all p < 0.01), plasma MLT secretion and the expression of MRs in duodenum, jejunum and ileum of ZDF rats decreased obviously (all p < 0.05), respectively. TaVNS can significantly reverse the hyperglycemia by regulating the non-pineal-derived MLT and MRs system in Px + taVNS group. Compared with the ZDF group, the expression of different intestinal MRs in the taVNS group was increased and more compactly arranged (both p < 0.05), the level of plasma MLT secretion was up-regulated (p < 0.01), and FBG and body weight were decreased (both p < 0.01). Meanwhile, after taVNS intervention in rats in the Px + taVNS group, we observed an increase in MLT secretion and the number of intestinal MRs compared with the taVNS group (all p > 0.05). In contrast, ZDF rats in which the pineal gland was excised by taVNS intervention and injected with the MRs antagonist Luzindole did not show these changes.

Conclusion

The glucose reduction effect of taVNS may be related to regulating MLT levels and expressing intestinal MRs.

Associations of prediabetes and sleep duration, and inflammation as a mediator in the China Health and Retirement Longitudinal Study

OBJECTIVE

The objective of this study was to examine the relationship between sleep duration and prediabetes, as well as to evaluate the influence of inflammation in mediating this association.

METHODS

A total of 4632 participants from the China Health and Retirement Longitudinal Study (CHARLS) were included in this study, comprising both baseline and 4-year follow-up data. The prospective relationship between sleep duration and the risk of prediabetes was examined using logistic regression models. We used multinomial logistic regression to evaluate the impact of prediabetes on sleep duration changes over follow-up, assessing the role of C-reactive protein in the association using mediation analysis.

RESULTS

Participants with short sleep duration (<5 hours) had a higher risk of prediabetes (odds ratios=1.381 [95% CI: 1.028-1.857]) compared to those with normal sleep durations (7-8 hours). However, excessive sleep durations (≥9 hours) did not show a statistically significant association with prediabetes risk. Moreover, individuals at least 60years old who experienced short sleep durations exhibited a higher risk of prediabetes. Individuals with prediabetes were more likely to have shorter sleep duration than excessive sleep duration (relative risk ratios=1.280 [95% CI: 1.059-1.547]). The mediation analysis revealed a mediating effect of C-reactive protein on the association between prediabetes and reduced sleep duration.

CONCLUSIONS

Short sleep duration was identified as a risk factor for the incidence of prediabetes. Conversely, prediabetes was found to contribute to shorter sleep duration rather than excessive sleep duration. Moreover, elevated levels of C-reactive protein may serve as a potential underlying mechanism that links prediabetes with shorter sleep.

Rev-erbα attenuates diabetic myocardial injury through regulation of ferroptosis

Diabetes is a widespread disease that threatens the life and health of human beings, and diabetic cardiomyopathy (DCM) is one of the major complications of diabetic patients. The pathological mechanisms of DCM are complex, including inflammation, endoplasmic reticulum stress, and oxidative stress that have been reported previously. Although recent studies suggested that ferroptosis is also involved in the progression of DCM, the exact mechanism remains unclear. Rev-erbα cardiac conditional knockout mice were generated and type 2 diabetes were induced by high fat diet (HFD) and intraperitoneal injection of streptozotocin (STZ) in in vivo experiments. In parallel, our in vitro experiments entailed the introduction of elevated levels of glucose (HG) and palmitic acid (PA) to induce glycolipid toxicity in H9c2 cardiomyocytes. Further deterioration of cardiac function was detected by echocardiography after the clock gene rev-erbα was knocked out. This was accompanied by significant elevations in markers of inflammation, myocardial fibrosis, and oxidative stress. In addition, iron content, transmission electron microscopy (TEM), and RT-PCR assays confirmed significantly increased levels of ferroptosis in rev-erbα-deficient DCM. Intriguingly, Co-Immunoprecipitation (Co-IP) data uncovered an interaction between rev-erbα and nuclear factor E2-related factor 2 (NRF2) in diabetic myocardial tissues. It is worth highlighting that ferroptosis within cardiomyocytes witnessed significant mitigation upon the administration of sulforaphane (SFN), an NRF2 agonist, to HG + PA-incubated H9c2 cells. Our study demonstrates for the first time that knockdown of the clock gene rev-erbα exacerbates myocardial injury and ferroptosis in type 2 diabetic mice, which can be reversed by activating NRF2.

12-week melatonin administration had no effect on diabetes risk markers and fat intake in overweight women night workers

Introduction

Interactions between circadian clocks and key mediators of chronic low-grade inflammation associated with fat consumption may be important in maintaining metabolic homeostasis and may pose a risk for the development of obesity-associated comorbidities, especially type 2 diabetes (T2DM).

Objective

The aims of the present study were to evaluate the effects of melatonin administration on diabetes risk markers according to dietary lipid profile (pro-inflammatory versus anti-inflammatory) in excessive weight night workers, and to determine the effect of administration on fat consumption profile.

Methods

A randomized, controlled, double-blind, crossover clinical trial involving 27 nursing professionals working permanent night shifts under a 12×36-hour system. The melatonin group (12 weeks) used synthetic melatonin (3 mg) only on days off and between shifts, while the placebo group (12 weeks) was instructed to take a placebo, also on days off and between shifts. For inflammatory characteristics, participants were divided into pro-inflammatory (saturated fats, trans fats and cholesterol) and anti-inflammatory (monounsaturated, polyunsaturated fats and EPA + DHA) groups according to fatty acid determinations. At baseline and at the end of each phase, blood glucose, insulin, glycosylated hemoglobin plasma concentrations were collected, and HOMA-IR was calculated.

Conclusion

Melatonin administration for 12 weeks had no effect on T2DM risk markers according to dietary lipid profile (pro-inflammatory or anti-inflammatory potential) in excessive weight night workers. Among the limitations of the study include the fact that the low dose may have influenced the results expected in the hypothesis, and individual adaptations to night work were not evaluated. The insights discussed are important for future research investigating the influence of melatonin and fats considered anti- or pro-inflammatory on glucose and insulin homeostasis related to night work.

Effect of oral melatonin treatment on insulin resistance and diurnal blood pressure variability in night shift workers. A double-blind, randomized, placebo-controlled study

BACKGROUND

Night shift work is associated with sleep disturbances, obesity, and cardiometabolic diseases. Disruption of the circadian clock system has been suggested to be an independent cause of type 2 diabetes and cardiovascular disease in shift workers. We aimed to improve alignment of circadian timing with social and environmental factors with administration of melatonin.

METHODS

In a randomized, placebo-controlled, prospective study, we analysed the effects of 2 mg of sustained-release melatonin versus placebo on glucose tolerance, insulin resistance indices, sleep quality, circadian profiles of plasma melatonin and cortisol, and diurnal blood pressure profiles in 24 rotating night shift workers during 12 weeks of treatment, followed by 12 weeks of wash-out. In a novel design, the time of melatonin administration (at night or in the morning) depended upon the shift schedule. We also compared the baseline profiles of the night shift (NS) workers with 12 healthy non-night shift (NNS)-working controls.

RESULTS

We found significantly impaired indices of insulin resistance at baseline in NS versus NNS (p < 0.05), but no differences in oral glucose tolerance tests nor in the diurnal profiles of melatonin, cortisol, or blood pressure. Twelve weeks of melatonin treatment did not significantly improve insulin resistance, nor did it significantly affect diurnal blood pressure or melatonin and cortisol profiles. Melatonin administration, however, caused a significant improvement in sleep quality which was significantly impaired in NS versus NNS at baseline (p < 0.001).

CONCLUSIONS

Rotating night shift work causes mild-to-moderate impairment of sleep quality and insulin resistance. Melatonin treatment at bedtime improves sleep quality, but does not significantly affect insulin resistance in rotating night shift workers after 12 weeks of administration.

Circadian Disruption in Night Shift Work and Its Association with Chronic Pulmonary Diseases

Globalization and the expansion of essential services over continuous 24 h cycles have necessitated the adaptation of the human workforce to shift-based schedules. Night shift work (NSW) causes a state of desynchrony between the internal circadian machinery and external environmental cues, which can impact inflammatory and metabolic pathways. The discovery of clock genes in the lung has shed light on potential mechanisms of circadian misalignment in chronic pulmonary disease. Here, the current knowledge of circadian clock disruption caused by NSW and its impact on lung inflammation and associated pathophysiology in chronic lung diseases, such as asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, and COVID-19, is reviewed. Furthermore, the limitations of the current understanding of circadian disruption and potential future chronotherapeutic advances are discussed.

Shift Work is Associated with an Elevated White Blood Cell Count: A Systematic Review and Meta-Analysis

The white blood cell (WBC) count increases significantly in reaction to infections and certain chronic diseases. Shift employment increases the risk for chronic low-grade inflammation and the progression of several chronic diseases. The objective of this study was to systematically evaluate the evidence from studies on total and differential WBC counts in shift employees. A literature search was performed in PubMed®, Web of Science, and Scopus databases using keywords for research published before March 1, 2022. A meta-analysis was conducted for total and differential WBC counts using a random-effects approach. A total of 25 studies covering a sample of 37,708 day and shift employees were included in this review. The studies represented America, Europe, East Asia, and Middle East. A significant increase in the total counts (×109/L) of WBC [mean difference (MD) = 0.43; 95% confidence interval (CI): 0.34-0.52; P < 0.001], lymphocytes (MD = 0.16; 95% CI: 0.02-0.30; P = 0.02), monocytes (MD = 0.04; 95% CI: 0-0.07; P = 0.03), and eosinophils (MD = 0.01; 95% CI: 0-0.01; P = 0.03) was observed in shift workers compared to the day counterparts. However, neutrophils and basophils were not significantly different between the groups. Shift work significantly increases the total and differential blood counts in peripheral circulation. Therefore, total and differential WBC counts represent a relatively inexpensive biomarker for diagnostics and prognostics of diseases in shift workers.

The Burden of Comorbidities in Obstructive Sleep Apnea and the Pathophysiologic Mechanisms and Effects of CPAP

Micro-arousals and the repeated desaturation of oxyhemoglobin, which are typical in obstructive sleep apnea syndrome (OSAS), have adverse effects on the health of patients, leading to a wide range of complications such as cardiovascular (arterial hypertension, pulmonary hypertension, chronic heart failure, arrhythmias, myocardial infarction), cerebrovascular (strokes), metabolic (insulin resistance, obesity, diabetes mellitus, metabolic syndrome), gastrointestinal (non-alcoholic liver disease), urinary (chronic renal failure), and neuropsychiatric complications as well as a wide range of malignancies. These, in turn, have multilateral effects on familial, occupational, and social life, as well as increasing the risks of road traffic accidents and accidents at the workplace. Awareness, timely screening, and the prevention of complications play important roles in diagnosing and treating comorbid conditions. This review focuses on comorbidities in OSAS and the effect of Continuous Positive Airway Pressure (CPAP) therapy on their prognoses.

LncRNA NKILA Exacerbates Alzheimer's Disease Progression by Regulating the FOXA1-Mediated Transcription of TNFAIP1

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases in the world, which seriously affects AD patients' life quality. Recently, long non-coding RNAs (lncRNAs) have been reported to play a key role in AD pathogenesis, however, the specific mechanism remains unclear. Herein, we aimed to investigate the role of lncRNA NKILA in AD. The learning and memory performance of rats from streptozotocin (STZ)-treated or other treated groups were tested by Morris water maze test. Relative levels of genes and proteins were measured using RT-qPCR and Western blotting. Mitochondrial membrane potential was tested by JC-1 staining. Levels of ROS, SOD, MDA, GSH-Px, and LDH were measured using corresponding commercial kits. Apoptosis was evaluated by TUNEL staining or Flow cytometry assay. RNA Immunoprecipitation (RIP), RNA pulldown, Chromatin immunoprecipitation (ChIP), and dual-luciferase reporter assays were utilized to test the interaction between indicated molecules. STZ treatment caused learning and memory impairment in rats and oxidative stress damage in SH-SY5Y cells. LncRNA NKILA was found to be elevated in the hippocampal tissues of rats and SH-SY5Y cells after STZ exposure. Knockdown of lncRNA NKILA alleviated STZ-induced neuronal damage. Furthermore, lncRNA NKILA could bind to ELAVL1, which regulate the stability of FOXA1 mRNA. Moreover, TNFAIP1 transcription process was controlled by FOXA1, which targeted the promoter of TNFAIP1. In vivo results demonstrated that lncRNA NKILA accelerated STZ-induced neuronal damage and oxidative stress by FOXA1/TNFAIP1 axis. Our findings indicated that knockdown of lncRNA NKILA inhibited the neuronal damage and oxidative stress induced by STZ through the FOXA1/TNFAIP1 axis, thereby alleviating the development of AD, revealing a promising therapeutic axis for AD treatment.

Molecular Mechanisms of the Melatonin Receptor Pathway Linking Circadian Rhythm to Type 2 Diabetes Mellitus

Night-shift work and sleep disorders are associated with type 2 diabetes (T2DM), and circadian rhythm disruption is intrinsically involved. Studies have identified several signaling pathways that separately link two melatonin receptors (MT1 and MT2) to insulin secretion and T2DM occurrence, but a comprehensive explanation of the molecular mechanism to elucidate the association between these receptors to T2DM, reasonably and precisely, has been lacking. This review thoroughly explicates the signaling system, which consists of four important pathways, linking melatonin receptors MT1 or MT2 to insulin secretion. Then, the association of the circadian rhythm with MTNR1B transcription is extensively expounded. Finally, a concrete molecular and evolutionary mechanism underlying the macroscopic association between the circadian rhythm and T2DM is established. This review provides new insights into the pathology, treatment, and prevention of T2DM.

Association between Shift Work Schedules and Cardiovascular Events in a Multi-Ethnic Cohort

BACKGROUND

Shift work is known to increase the risk of cardiometabolic diseases and mortality. We investigate the relationship between shift work schedules and cardiometabolic risk factors (smoking, hypertension, and obesity) and their association with cardiometabolic diseases (diabetes and cardiovascular diseases) in a multi-ethnic population from Singapore.

METHODS

2469 participants from the Singapore-based Multi-Ethnic Cohort underwent physical and clinical assessments. Shift work schedules (morning, evening, night, and mixed) were assessed using a validated questionnaire.

RESULTS

Among shift workers, night shift workers had a significantly higher prevalence of smoking (54.5%), diabetes (27.3%), and cardiovascular events (14.1%). Compared to non-shift workers, workers in the night (OR = 2.10, 95%CI: 1.26-3.41) and mixed (OR = 1.74, 95%CI: 1.22-2.48) shift groups were more likely to be current smokers. A significant association between shift duration and smoking (OR = 1.02, 95%CI: 1.00-1.03) was also observed, with longer shift duration (in years) leading to an increase in smoking behavior. No significant associations were found between shift work schedules and hypertension, obesity (BMI), diabetes, and cardiovascular disease, as well as other cardiometabolic risk factors and diseases.

CONCLUSION

This study found that shift schedules and shift duration were most strongly associated with smoking status after covariate adjustments (age, gender, ethnicity, socioeconomic status, and work arrangement), with night and mixed shift types being strongly associated with current smoker status. As smoking is a modifiable risk factor for cardiometabolic disease, employers of shift workers should increase work-based health interventions to control smoking and promote a healthier workforce.

Impact of light therapy on rotating night shift workers: the EuRhythDia study

AIMS

Disturbances in circadian rhythms may promote cardiometabolic disorders in rotating night shift workers (r-NSWs). We hypothesized that timed light therapy might reverse disrupted circadian rhythms and glucose intolerance observed among r-NSWs).

METHODS

R-NSWs were randomly assigned to a protocol that included 12 weeks on followed by 12 weeks off light therapy (n = 13; 6 men; mean age, 39.5 ± 7.3 years) or a no-treatment control group (n = 9; 3 men; mean age 41.7 ± 6.3 years). Experimental and control participants underwent identical metabolic evaluations that included anthropometric, metabolic (including oral glucose tolerance tests), lipid, and inflammation-associated parameters together with an assessment of sleep quality and expression of circadian transcription factors REV-ERBα and BMAL1 in peripheral blood mononuclear cells (PBMCs) at baseline, 12 weeks, and 24 weeks of the protocol.

RESULTS

Twelve weeks of warm white-light exposure (10,000 lx at 35 cm for 30 min per day) had no impact on sleep, metabolic, or inflammation-associated parameters among r-NSWs in the experimental group. However, our findings revealed significant decreases in REV-ERBα gene expression (p = 0.048) and increases in the REV-ERBα/BMAL1 ratio (p = 0.040) compared to baseline in PBMCs isolated from this cohort. Diminished expression of REV-ERBα persisted, although the REV-ERBα/BMAL1 ratio returned to baseline levels after the subsequent 12-day wash-out period.

CONCLUSIONS

Our results revealed that intermittent light therapy had no impact on inflammatory parameters or glucose tolerance in a defined cohort of r-NSWs. However, significant changes in the expression of circadian clock genes were detected in PBMCs of these subjects undergoing light therapy.

Healthy Sleep Every Day Keeps the Doctor Away

When one considers the big picture of their health, sufficient sleep may often go overlooked as a keystone element in this picture. Insufficient sleep in either quality or duration is a growing problem for our modern society. It is essential to look at what this means for our health because insufficient sleep increases our risks of innumerable lifechanging diseases. Beyond increasing the risk of developing these diseases, it also makes the symptoms and pathogenesis of many diseases worse. Additionally, consistent quality sleep can not only improve our physical health but has also been shown to improve mental health and overall quality of life. Substandard sleep health could be a root cause for numerous issues individuals may be facing in their lives. It is essential that physicians take the time to learn about how to educate their patients on sleep health and try to work with them on an individual level to help motivate lifestyle changes. Facilitating access to sleep education for their patients is one way in which physicians can help provide patients with the tools to improve their sleep health. Throughout this paper, we will review the mechanisms behind the relationship between insufficient sleep health and chronic disease and what the science says about how inadequate sleep health negatively impacts the overall health and the quality of our lives. We will also explain the lifechanging effects of sufficient sleep and how we can help patients get there.

Factors Associated with Gastrointestinal Symptoms among Rotating Shift Nurses in South Korea: A Cross-Sectional Study

Rotating shift work places a serious burden on nurses' physical and psychological health. Gastrointestinal (GI) symptoms are a common complaint among shift workers. This study assessed GI symptoms and identified the associations between dietary habits, psychological status, and sleep quality among rotating shift nurses. Data from 125 female nurses in rotating shifts who worked at two tertiary hospitals in South Korea were collected using a questionnaire that included the Gastrointestinal Symptoms Questionnaire; the Dietary Habit Questionnaire; the Depression, Anxiety, Stress Scale (DASS)-21; and the Pittsburgh Sleep Quality Index (PSQI). All participants experienced various GI symptoms, and 47% of them complained of at least one severe GI symptom. There were significant differences in GI symptom scores according to the status of depression, anxiety, stress, and sleep quality. In multiple linear regression analysis, the factors associated with an increase in the occurrence and severity of GI symptoms were poor sleep quality and morbid anxiety and stress. The model explained power at 43.2%. As most nurses in rotating shifts experience GI symptoms, they should receive counseling and training programs at work to alleviate psychological symptoms, improve sleep quality, and pay more attention to their health status as well as GI symptom management.

Night Shift Work Is Associated with Reduced Rate of Humoral Response Following Vaccination for HBV

Night shift work has been associated with cardiovascular and metabolic disease, endocrine and immunological disorders. Published studies have reported that a reduced total sleep time with sleep-wake cycle alterations were associated with a reduced rate of humoral response following vaccination. Our study aimed to evaluate the association between night shift work and serological status for HBV among workers employed in a university hospital in Rome. We evaluated medical records of 986 HCWs working at Tor Vergata Policlinic of Rome. We screened all study subjects for anti-HBs IgG, anti-HBc IgG and HBsAg. Serological protection for HBV was evaluated in relation to sex, age group, job task, risk setting and night shift work status. Protective titer was found in 856 (86.8%) study participants and the mean titer was significantly high in females, in subjects aged less than 40 years, in night shift workers and in high-risk setting workers. After adjustment for study covariates, night shift work was no longer associated with an HBV-protective titer. This finding suggests that a vaccination strategy for dampening HBV transmission should be carefully addressed in health care workers (HCWs) doing night shift.

Post-Work Recovery from Fatigue and Sleep Episodes among Nurses Who Are Engaged in 16-Hour Night Shifts: A Prospective Observational Study

Poor recovery from fatigue among shift-working nurses can cause a transition from acute to chronic fatigue. We aimed to clarify the relationship between nurses' recovery from fatigue and sleep episodes after 16 h night shifts while considering age. This prospective study included 62 nurses who worked 16 h night shifts. Fatigue was assessed by a questionnaire before, during, and after the night shift, and the morning following the night shift. Sleep episodes were continuously measured using a wearable device. We performed a hierarchical cluster analysis of multivariate sleep parameters in first and main sleep episodes after night shifts. A linear mixed model was used to estimate the difference between clusters in recovery from fatigue after the night shift, considering age. The participants were classified into a high sleep quality group (HSQG) and low sleep quality group (LSQG) in sleep episodes after the night shift. There was a significant main effect of clusters, and HSQG was significantly more effective than LSQG in recovering from fatigue. However, no main effects of age or interaction were observed. The quality of first and main sleep episodes at home was associated with recovery from the night shift to the next day, regardless of age.

Sleep Quality among Patients with Type 2 Diabetes: A Cross-Sectional Study in the East Coast Region of Peninsular Malaysia

Poor sleep is related to type 2 diabetes and adversely influences a person’s quality of life. This study aimed to evaluate sleep quality in patients with type 2 diabetes (T2DM), its associated factors, and its relationship with quality of life. A cross-sectional study was conducted at a primary care clinic in a tertiary hospital on the east coast of Malaysia. This study included 350 participants (175 men and 175 women). Data were collected using the Malay version of the Pittsburgh Sleep Quality Index (PSQI-M) with a cut-off point of >5 as poor sleep, the Malay version of Diabetes Distress Scale (MDDS-17) and the revised Malay version of T2DM-related quality of life (Rv-DQOL). Statistical analysis was conducted using the SPSS software version 26.0. The respondents’ median (interquartile range (IQR)) age was 62.0 (11.0) years, and poor sleep was reported in 32% (95% confidence interval (CI) = 27.1, 36.9) of the participants. Multivariate logistic regression analysis revealed that poor sleep quality was significantly associated with nocturia (odds ratio (OR) = 2.04; 95% CI = 1.24, 3.35), restless legs syndrome (OR = 2.17; 95% CI = 1.32−3.56) and emotional burden (OR = 2.37; 95% CI = 1.41−3.98). However, no statistically significant association was observed between sleep quality and quality of life among our participants.

Variations in glycated haemoglobin with age among individuals with normal glucose tolerance: Implications for diagnosis and treatment-Results from the ICMR-INDIAB population-based study (INDIAB-12)

AIM

To report on glycated haemoglobin (HbA1c) values among individuals with normal glucose tolerance (NGT) at different age groups, using data acquired from a large national survey in India.

MATERIALS AND METHODS

Data on glycaemic parameters at different age groups were obtained from the Indian Council of Medical Research-INdia DIABetes (ICMR-INDIAB) study, in adults aged ≥ 20 years representing all parts of India. Age-wise distribution of HbA1c was assessed among individuals with NGT (n = 14,222) confirmed by an oral glucose tolerance test using the World Health Organization (WHO) criteria. Results were validated in another large epidemiological study (n = 1077) conducted in Chennai, India.

RESULTS

Among NGT individuals, HbA1c increased gradually with age from 5.16 ± 0.71% (33 mmol/mol) in the age group of 20-29 years to 5.49 ± 0.69% (37 mmol/mol) in those aged 70 + years. In the validation study, conducted in another study population, HbA1c was 5.35 ± 0.43% (35 mmol/mol) in age group of 20-29 years and 5.74 ± 0.50% (39 mmol/mol) in those aged 70 and above. In the INDIAB study, for every decadal increase in age, there is a 0.08% increase in HbA1c and this increase was more significant in females (females: 0.10% vs. males: 0.06%) and in urban (urban: 0.10% vs. rural: 0.08%) population.

CONCLUSIONS

HbA1c levels increase steadily with age. This suggests that age-specific cutoffs be used while utilizing HbA1c to diagnose diabetes and prediabetes, so as to minimize the risk of overdiagnosis and unnecessary initiation of treatment in elderly people who could have physiological increase in HbA1c levels.

Reduced Titers of Circulating Anti-SARS-CoV-2 Antibodies and Risk of COVID-19 Infection in Healthcare Workers during the Nine Months after Immunization with the BNT162b2 mRNA Vaccine

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has had a tremendous impact on health services; hundreds of thousands of healthcare workers (HCWs) have died from coronavirus disease 2019 (COVID-19). The introduction of the BNT162b2 mRNA vaccine in Italy provided recipients with significant protection against COVID-19 within one to two weeks after the administration of the second of the two recommended doses. While the vaccine induces a robust T cell response, the protective role of factors and pathways other than those related to memory B cell responses to specific SARS-CoV-2 antigens remains unclear. This retrospective study aimed to evaluate the determinants of serological protection in a group of vaccinated HCWs (n = 793) by evaluating circulating levels of antiviral spike receptor-binding domain (S-RBD) antibodies during the nine-month period following vaccination. We found that 99.5% of the HCWs who received the two doses of the BNT162b2 vaccine developed protective antibodies that were maintained at detectable levels for as long as 250 days after the second dose of the vaccine. Multivariate analysis was performed on anti-S-RBD titers in a subgroup of participants (n = 173) that were evaluated twice during this period. The results of this analysis reveal that the antibody titer observed at the second time point was significantly related to the magnitude of the primary response, the time that had elapsed between the first and the second evaluation, and a previous history of SARS-CoV-2 infection. Of importance is the finding that despite waning antibody titers following vaccination, none of the study participants contracted severe COVID-19 during the observational period.

The relationship between the elevation of haemoglobin A1c level, sleep quality and sleep duration in clinically diagnosed pre-diabetic patients in a nationally representative sample

BACKGROUND/OBJECTIVES

Type 2 diabetes mellitus (T2DM) is one of the most common chronic illnesses in the United Kingdom accounting for approximately 15% of deaths per year. Growing evidence suggests that sleep duration and quality contributes towards this. This study aimed to determine whether there was a significant relationship between the elevation of haemoglobin A1c (HbA1c) level, sleep quality (SQ) and sleep duration (SD) in clinically diagnosed pre-diabetic patients.

SUBJECTS/METHODS

Following referral from a relevant healthcare professional, participants (n = 40) were registered on the National Health Service England, funded Healthier You: National Diabetes Prevention Programme and completed a Pittsburgh Sleep Quality Index questionnaire to evaluate SQ and SD.

RESULTS

A Spearman's correlation showed an association between HbA1c, SQ and SD measures. A simple linear regression showed a significant large positive association (rs = 0.913, p < 0.001) and significant regression (F (1) = 39, p < 0.001) with an R2 of 0.842 between HbA1c level and SQ. Additionally, a significant large negative association (rs = 0.757, p < 0.001) and significant regression was found (F (1) = 39, p < 0.001) with an R2 of 0.570 between HbA1c and SD.

CONCLUSIONS

This study suggests a relationship between SQ, SD and the elevation of HbA1c which may contribute towards prevalence of T2DM and may help to increase adherence to diabetes prevention programmes.

The Circadian Clock and Obesity

The modern way of life has dramatically affected our biological rhythms. Circadian rhythms, which are generated by an endogenous circadian clock, are observed in a large number of physiological functions including metabolism. Proper peripheral clock synchronization by different signals including appropriate feeding/fasting cycles is essential to coordinate and temporally gate metabolic processes. In this chapter, we emphasize the importance of nutrient sensing by peripheral clocks and highlight the major role of peripheral and central clock communication to locally regulate metabolic processes and ensure optimal energy storage and expenditure. As a consequence, changes in eating behavior and/or bedtime, as occurs upon shift work and jet lag, have direct consequences on metabolism and participate in the increasing prevalence of obesity and associated metabolic diseases such as type 2 diabetes and non-alcoholic fatty liver disease. In this setting, time-restricted feeding has been suggested as an efficient approach to ameliorate metabolic parameters and control body weight.

Factors Associated with Pre-Vaccination SARS-CoV-2 Infection Risk among Hospital Nurses Facing COVID-19 Outbreak

The objective of this work was to evaluate the magnitude of COVID-19 spread and the related risk factors among hospital nurses employed in a COVID hospital in Rome, before the beginning of the vaccination programmes commenced in 2021. Participants periodically underwent (every 15–30 days) nasopharyngeal swab and/or blood sample for SARS-CoV-2 IgG examination. From 1 March 2020 to 31 December 2020, we found 162 cases of COVID-19 infection (n = 143 nasopharyngeal swab and n = 19 IgG-positive) in a total of 918 hospital nurses (17.6%). Most SARS-CoV-2-infected hospital nurses were night shift workers (NSWs), smokers, with higher BMI and lower mean age than that of individuals who tested negative. After adjusting for covariates, age (OR = 0.923, 95% C.I. 0.895–0.952), night shift work (OR = 2.056, 95% C.I. 1.320–2.300), smoking status (OR = 1.603, 95% C.I. 1.080–2.378) and working in high-risk settings (OR = 1.607, 95% C.I. 1.036–2.593) were significantly associated with SARS-CoV-2 hospital infection, whereas BMI was not significantly related. In conclusion, we found a high prevalence of SARS-CoV-2 infection among hospital nurses at a Rome COVID hospital in the pre-vaccination period. Smoking, young age, night shift work and high-risk hospital settings are relevant risk factors for hospital SARS-CoV-2 infection; therefore, a close health surveillance should be necessary among hospital nurses exposed to SARS-CoV-2.

Physical Activity as a Predictor of the Level of Stress and Quality of Sleep during COVID-19 Lockdown

Background: The coronavirus pandemic and the government restrictions significantly disturbed the daily functioning of people, thereby influencing healthy behaviors, such as physical activity—the core indicator of well-being. This study evaluates the associations between physical activity (PA), the level of stress and quality of sleep during the COVID-19 pandemic lockdown. Methods: An online survey was distributed during the governmental lockdown in April 2020 and included measures for assessing physical activity, stress and sleep. The surveyed participants included all adults aged 18 years and over. The final data were collected from the 1959 respondents using: International Physical Activity Questionnaire-Short Form (IPAQ-SF), Perceived Stress Scale (PSS) and Pittsburgh Sleep Quality Index (PSQI). Findings: Almost half of the respondents indicated a low level of PA, performing only 60 min of PA daily. Most of the participants reported a moderate or high level of stress (57% and 29%, respectively) and 64% of them reported poor quality of sleep. People with low levels of stress performed on average 85.1 min/day of walking (WPA), 40.9 min/day of moderate PA (MPA) or 52.6 min/day of vigorous PA (VPA). People with good quality of sleep performed 82.9 min/day of WPA, 43.6 min/day MPA and 40.5 min/day VPA. Interpretation: The results from the study indicate that the volume of daily PA may be a predictor of the level of stress and sleep quality in adults during the COVID-19 pandemic lockdown. To retain a low level of stress and good quality of sleep, a lifestyle that allows to achieve a moderate level of physical activity should be maintained. The optimal daily dose of PA is at least 70 min per day, involving different intensities.

Sleep Quality Is Associated with Vitamin B12 Status in Female Arab Students

Studies have explored how vitamin B12 status affects sleep among elders and children, but this remains to be investigated among young adults. We used the Pittsburgh Sleep Quality Index (PSQI) to assess the association between serum vitamin B12 and sleep among female college students in Saudi Arabia. In this cross-sectional study, we enrolled 355 participants (age (years), 20.7 ± 1.5; body mass index, 23.6 kg/m² ± 5.2) at King Saud University, Riyadh, Saudi Arabia. Fasting blood samples were analyzed regarding the serum vitamin B12 and blood lipids. Anthropometric, socio-demographic, clinical history, stress, physical activity, and dietary data were collected. We assessed the sleep statuses of the participants using the PSQI. Around 72% of the participants were “poor” sleepers (PSQI > 5). Subgroup analysis within the tertiles showed that participants with higher vitamin B12 in the second and third tertiles reported better scores for sleep quality (B ± SE = −12.7 ± 5.6, p = 0.03; B ± SE = −32.7 ± 16.4, p = 0.05, respectively) and also reported a lower use of sleep medication (B ± SE = −21.2 ± 9.9, p = 0.03, in the second tertile only), after adjusting for the waist–hip ratio and stress. However, sleep was not found to be directly associated with either serum vitamin B12 or dietary vitamin B12. In conclusion, the serum vitamin B12 results show that the participants with higher vitamin B12 in the second and third tertiles reported better scores on the sleep quality scale and a lower use of sleep medication. However, no such associations were observed with the overall PSQI. More studies with larger sample sizes are needed to establish a direct relationship between sleep and vitamin B12.