Association between the weight-adjusted-waist index and circadian syndrome in findings from a nationwide study.

Weight-adjusted-waist index (WWI) is an emerging parameter for evaluating obesity. We sought to ascertain the link between WWI and circadian syndrome (CircS). The study population consisted of 8275 eligible subjects who were included in the ultimate analysis from the NHANES 2011-2018. By using multivariable regression models, the association of WWI and CircS was analyzed. In subgroup analysis, we explored the relationship in different groups and tested the stability of the intergroup connection using interaction testing. To investigate whether WWI and CircS had a potential non-linear relationship, smooth curve fittings, and threshold effects tests were also constructed. In a multivariate linear regression model, WWI is significantly positively related to CircS (OR = 1.77, 95% CI 1.50-2.08). Through subgroup analysis and interaction testing, the stability of this positive association was also validated. It was further found that there was an inverted U-shaped association, with a turning point of 11.84, between WWI and CircS. Our findings supported a strong association between WWI values and CircS. Central obesity management is pivotal for preventing or alleviating CircS.

Aging abolishes circadian rhythms and disrupts temporal organization of antioxidant-prooxidant status, endogenous clock activity and neurotrophin gene expression in the rat temporal cortex.

Disruption of circadian rhythms contributes to deficits in cognitive functions during aging. Up to date, the biochemical, molecular and chronobiological bases of such deterioration have not been completely elucidated. Here, we aim: 1) to investigate the endogenous nature of 24 h-rhythms of antioxidant defenses, oxidative stress, clock's, and neurotrophic factors expression, in the rat temporal cortex (TC), and 2) to study the consequences of aging on the circadian organization of those factors. We observed a circadian organization of antioxidant enzymes activity, lipoperoxidation and the clock, BMAL1 and RORa, proteins, in the TC of young rats. Such temporal organization suggests the existence of a two-way communication among clock transcription factors and antioxidant defenses. This might generate the rhythmic and circadian expression of Bdnf and Rc3 genes involved in the TC-depending cognitive function. Noteworthy, such circadian organization disappears in the TC of aged rats. Aging also reduces glutathione peroxidase activity and expression, and it increases lipid peroxidation, throughout a 24 h-period. An increased oxidative stress makes the cellular redox environment change into an oxidative status which alters the endogenous clock activity and disrupts the circadian organization of, at least part, of the molecular basis of the synaptic plasticity in the TC.

The influence of time of day on memory recognition for faces.

Time of day can alter memory performance in general. Its influence on memory recognition performance for faces, which is important for daily encounters with new persons or testimonies, has not been investigated yet. Importantly, high levels of the stress hormone cortisol impair memory recognition, in particular for emotional material. However, some studies also reported high cortisol levels to enhance memory recognition. Since cortisol levels in the morning are usually higher than in the evening, time of day might also influence recognition performance. In this pre-registered study with a two-day design, 51 healthy men encoded pictures of male and female faces with distinct emotional expressions on day one around noon. Memory for the faces was retrieved two days later at two consecutive testing times either in the morning (high and moderately increased endogenous cortisol levels) or in the evening (low endogenous cortisol levels). Additionally, alertness as well as salivary cortisol levels at the different timepoints was assessed. Cortisol levels were significantly higher in the morning compared to the evening group as expected, while both groups did not differ in alertness. Familiarity ratings for female stimuli were significantly better when participants were tested during moderately increased endogenous cortisol levels in the morning than during low endogenous cortisol levels in the evening, a pattern which was previously also observed for stressed versus non-stressed participants. In addition, cortisol levels during that time in the morning were positively correlated with the recollection of face stimuli in general. Thus, recognition memory performance may depend on the time of day and as well as on stimulus type, such as the difference of male and female faces. Most importantly, the results suggest that cortisol may be meaningful and worth investigating when studying the effects of time of day on memory performance. This research offers both, insights into daily encounters as well as legally relevant domains as for instance testimonies.

Therapeutic use of music in neurological disorders: A concise narrative review.

Background: Music elicits multifactorial benefits in emotional, social, cognitive, and academic aspects of human life. Music is clinically proven to reduce stress and anxiety, and improve mood and self-expression, particularly after traumatic events. Studies have also demonstrated that music promotes parasympathetic autonomic systems, suppresses hyperactivation of stress responses, and boosts immune functions. However, its ability to promote brain plasticity and signalling are only beginning to be realized. Moreover, its employment as a therapy for the treatment of specific aspects of other neurological disorders, including neurodevelopmental and neurodegenerative conditions and their comorbidities, is fast becoming an interesting field of research. Objective: The aim of this review is to summarize some of the recent studies focused on evaluating the applications of music therapy. For this purpose, we have focused on disorders encompassing both temporal extremities of brain developmental stages, from developmental conditions of autism and attention deficit hyperactivity disorder (ADHD), to ageing-related pathologies of Parkinson's disease and dementias. Results: The findings of the reviewed studies indicate potent utilities of music-based interventions in beneficially affecting multiple spheres of brain functions, such as sensorimotor, auditory, communication/language, psychological/emotional, behavioural, sleep and memory and cognitive attributes of patients diagnosed with diverse neuropathologies. Nevertheless, lack of standardized protocols for music provision as well as absence of information regarding key aspects, such as cultural and musical orientations of subjects and therapists'/caregivers' attitudes, have hindered the complete realization of music's therapeutic potential for neurological conditions. Further, while some studies have undertaken assessments of core neurophysiological mechanisms underlying music therapy, this information is largely lacking for most clinical studies. Conclusion: While this is not an exhaustive review of literature, we do hope that it serves as a platform to promote future research for establishing music therapy as a relevant neurotherapeutic strategy.

Loss of endogenous circadian clock function in mice alters respiratory cycle timing in a time of day- and sex-specific manner.

Resting breathing and ventilatory chemoreflexes are regulated in a 24-hr manner by the endogenous circadian clock. However, it is unclear how circadian biology influences different phases of the breath-to-breath respiratory cycle which are predominantly controlled by pontomedullary regions of the brainstem. Here, we performed whole-body plethysmography during quiet wakefulness in young adult male and female mice lacking the core clock gene Brain and Muscle Arnt-like 1 (BMAL1) to determine the extent to which the molecular clock affects respiratory cycle timing and ventilatory airflow mechanics. Breath waveform analysis revealed that male BMAL1 knockout (KO) mice exhibit time of day-specific differences in inspiratory and expiratory times, total cycle length, end inspiratory pause, relaxation time, and respiratory rate compared to wild-type littermates. Notably, changes in respiratory pattern were not observed in female BMAL1 KO mice when compared to wild-type females. Additionally, BMAL1 deficiency did not disrupt overall minute ventilation or peak airflow in either sex, suggesting total ventilatory function during quiet wakefulness is preserved. Taken together, these findings indicate that genetic disruption of the circadian clock in mice elicits sex-specific changes in respiratory cycle timing.

Index assessment of periodontal status in patients on the background of administering a drug with circadian activity.

OBJECTIVE: Aim: The aim of this study was to determine the effect of application of drug with circadian activity (pioglitazone) for treatment of patients with periodontist. PATIENTS AND METHODS: Materials and Methods: Group I - 18 individuals with healthy periodontium. Group II - 12 participants with stage II, grade B periodontitis treated with a standard treatment protocol. Group III - 12 participants with stage II, grade B periodontitis, treated with a regimen that included the standard protocol along with the administration of pioglitazone prescribed at recommended times of intake. Group IV - 12 participants with stage II, grade B periodontitis treated with the standard protocol and pioglitazone against the recommended intake hours. RESULTS: Results: The Simplified Oral Hygiene Index in Group I was 0.406±0.034. In Group II, it was 2.5±0.06. In Group III, the hygiene index was 2.633±0.056 and in Group IV it was 2.5±0.059. The Papillary-Marginal-Alveolar Index in Group I was 0.033±0.004. In Group II, it was 0.366±0.011. For Group III, the PMA index was 0.38±0.012 and for Group IV it was 0.378±0.01. The Russell's Periodontal Index in Group I was 0.111±0.008. In Group II, it was 4.668±0.155. For Group III - 4.708±0.132 and for Group IV it was 4.575±0.089. The Gingival Bleeding Index (GBI) in Group I was 0.031±0.003, while in Group II, it was 0.266±0.009, in Group III, it was 0.273±0.007 and in Group IV it was 0.278±0.006. CONCLUSION: Conclusions: The administration of pioglitazone (the drug with circadian activity) according to its circadian stage indeed has a positive effect on the periodontal status changes of patients with stage II, grade B periodontitis.

Association between chronic kidney disease stages and changes in ambulatory blood pressure monitoring parameters / Associação entre estágios da doença renal crônica e alterações dos parâmetros da monitorização ambulatorial da pressão arterial

Abstract Introduction: Blood pressure (BP) assessment affects the management of arterial hypertension (AH) in chronic kidney disease (CKD). CKD patients have specific patterns of BP behavior during ambulatory blood pressure monitoring (ABPM). Objectives: The aim of the current study was to evaluate the associations between progressive stages of CKD and changes in ABPM. Methodology: This is a cross-sectional study with 851 patients treated in outpatient clinics of a university hospital who underwent ABPM examination from January 2004 to February 2012 in order to assess the presence and control of AH. The outcomes considered were the ABPM parameters. The variable of interest was CKD staging. Confounding factors included age, sex, body mass index, smoking, cause of CKD, and use of antihypertensive drugs. Results: Systolic BP (SBP) was associated with CKD stages 3b and 5, irrespective of confounding variables. Pulse pressure was only associated with stage 5. The SBP coefficient of variation was progressively associated with stages 3a, 4 and 5, while the diastolic blood pressure (DBP) coefficient of variation showed no association. SBP reduction was associated with stages 2, 4 and 5, and the decline in DBP with stages 4 and 5. Other ABPM parameters showed no association with CKD stages after adjustments. Conclusion: Advanced stages of CKD were associated with lower nocturnal dipping and greater variability in blood pressure.

Resumo Introdução: A avaliação da pressão arterial (PA) tem impacto no manejo da hipertensão arterial (HA) na doença renal crônica (DRC). O portador de DRC apresenta padrão específico de comportamento da PA ao longo da monitorização ambulatorial da pressão arterial (MAPA). Objetivos: O objetivo do corrente estudo é avaliar as associações entre os estágios progressivos da DRC e alterações da MAPA. Metodologia: Trata-se de um estudo transversal com 851 pacientes atendidos nos ambulatórios de um hospital universitário que foram submetidos ao exame de MAPA no período de janeiro de 2004 a fevereiro de 2012 para avaliar a presença e o controle da HA. Os desfechos considerados foram os parâmetros de MAPA. A variável de interesse foi o estadiamento da DRC. Foram considerados como fatores de confusão idade, sexo, índice de massa corporal, tabagismo, causa da DRC e uso de anti-hipertensivos. Resultados: A PA sistólica (PAS) se associou aos estágios 3b e 5 da DRC, independentemente das variáveis de confusão. Pressão de pulso se associou apenas ao estágio 5. O coeficiente de variação da PAS se associou progressivamente aos estágios 3a, 4 e 5, enquanto o coeficiente de variação da pressão arterial diastólica (PAD) não demonstrou associação. O descenso da PAS obteve associação com estágios 2, 4 e 5, e o descenso da PAD, com os 4 e 5. Demais parâmetros da MAPA não obtiveram associação com os estágios da DRC após os ajustes. Conclusão: Estágios mais avançados da DRC associaram-se a menor descenso noturno e a maior variabilidade da pressão arterial.

Factors affecting sleep quality in hospitalised patients.

INTRODUCTION: Hospitalised patients are at increased risk of poor sleep quality which can negatively impact on recovery and quality of life. This study aimed to assess sleep quality in hospitalised patients and explore the factors associated with poor sleep. METHODS: Prospective data were collected from 84 respiratory ward inpatients at time of discharge using a Likert scale questionnaire on contributing factors to sleep quality. Differences between groups reporting good and poor quality sleep were recorded. RESULTS: Most participants (77%) described inpatient sleep quality to be worse or much worse compared to their home environment. Noise (39%), checking of vital signs (33%) and light (24%) were most frequently identified as factors disrupting sleep. Binary logistic regression analysis demonstrated that men (OR 2.8, CI 1.1-7.4, p = 0.037) and those in shared rooms (OR 3.9, CI 1.4-10.9, p = 0.009) were more likely to be affected by noise. Younger patients (OR 0.92, CI 0.88-0.96, p < 0.001) and those in shared rooms (OR 8.5 CI 1.9-37.9, p < 0.001) were more likely to be affected by light. CONCLUSION: In conclusion, a high proportion of hospitalised respiratory patients on a medical ward reported poorer sleep quality compared to home due to operational interruptions and noise. Age, gender and room type further modified the sleep disruption. Future research should focus on whether strategies to reduce interruptions and noise will improve sleep quality and clinical outcomes.

Influence of shift work on sleep quality and circadian patterns of heart rate variability among nurses.

Background: Shift work implementation is essential for providing continuous patient care in hospitals. However, working in shifts on a routine basis may disrupt the circadian pattern and alter the sleep-wakefulness cycle in nurses. Stress due to shift work can influence the adaptability of the cardiovascular system, produce psychophysiological strain and deteriorate work performance in female nurses. Objective: This study investigated the effect of morning and night shift work on sleep quality and circadian patterns governing heart rate variability (HRV) in female nurses working in a tertiary care hospital. Methods: Thirty-eight healthy female nurses were recruited. Frequency and time domain parameters of HRV were recorded as markers of cardiac autonomic function. A student t-test was used to investigate differences in HRV between morning and night shift workers. Mann-Whitney non-parametric test was applied for the difference between Pittsburgh Sleep Quality Index (PSQI) scores in the two groups. Results: Standard deviation of the normal-to-normal interval (SDNN) (msec), total power (ms2) and high-frequency (HF) band power (ms2) were significantly reduced in night shift nurses than in morning shift nurses. The low-frequency (LF)/HF ratio was significantly increased in night shift nurses. The differences in standard deviation of the averages of NN intervals (SDaNN) (msec), root mean square of successive differences between adjacent NN intervals (RMSSD), mean NN, very low-frequency (VLF) band power (ms2) and LF band power (ms2) were not statistically significant. The global PSQI score was significantly higher among night shift workers than in morning shifts. Conclusion: Inadequate sleep can disrupt the body's ability to regulate heart rhythm and increase the risk of cardiovascular diseases and mortality. The research suggests a propensity for autonomic imbalance in night shift workers when compared to their counterparts on morning shifts.

Circadian Temperature in Moderate to Severe Acute Stroke Patients.

Background: Stroke patients often present circadian disruption due to multiple causes e.g., primary disease, comorbidities, medication, immobilization, reduced daylight entrainment and sleep disturbances. Objective: To investigate the circadian rhythm of temperature in forehead skin in patients with moderate to severe stroke admitted for rehabilitation. Methods: A physiologic study in form of a secondary analysis of a former randomized study. In total 27 patients with moderate to severe stroke were included between May 1st 2014, and June 1st 2015. Circadian temperature was collected approx. seven days after admission at the acute stroke unit by a skin surface temperature probe as part of a Polysomnography (PSG) measurement. Results: Temperature variations show no circadian rhythm (Type 3 tests of fixed effects by SAS, p = 0.1610). The median temperature variance did fluctuate, but not significantly, and the small changes in circadian temperature variance did not follow the normal temperature variance. Conclusion: Patients with moderate to severe stroke show an abrogated circadian rhythm of temperature. There is an unmet need to understand the mechanisms for this, significance for stroke outcome and treatment.

Circadian rhythm of brain-derived neurotrophic factor in serum and plasma.

The neurotrophic growth factor brain-derived neurotrophic factor (BDNF) plays a crucial role in various neurodegenerative and psychiatric diseases, such as Alzheimer's disease, schizophrenia and depression. BDNF has been proposed as a potential biomarker for diagnosis, prognosis and monitoring therapy. Understanding the factors influencing BDNF levels and whether they follow a circadian rhythm is essential for interpreting fluctuations in BDNF measurements. We aimed to investigate the circadian rhythm of BDNF by collecting multiple peripheral venous blood samples from young, healthy male participants at 12 different time points over 24 h. In addition, vital parameters, cortisol and insulin like growth factor 1 (IGF1) were measured to explore potential regulatory mechanisms, interfering variables and their correlations with BDNF concentration. The findings revealed that plasma BDNF did not exhibit any significant fluctuations over 24 h, suggesting the absence of a circadian rhythm. However, serum BDNF levels decreased during sleep. Furthermore, serum BDNF showed a positive correlation with heart rate but a negative correlation with IGF1. No significant correlation was observed between cortisol and BDNF or IGF1. Although plasma BDNF suggests steady-state conditions, the decline of serum BDNF during the nocturnal period could be attributed to physical inactivity and associated with reduced haemodynamic blood flow (heart rate reduction during sleep). The type of sample collection (peripheral venous cannula vs. blood sampling using a butterfly system) does not significantly affect the measured BDNF levels. The sample collection during the day did not significantly affect BDNF analysis, emphasizing the importance of considering activity levels rather than timing when designing standardized protocols for BDNF assessments.

Prediction of lung adenocarcinoma prognosis and diagnosis with a novel model anchored in circadian clock-related genes.

Lung adenocarcinoma is the most common primary lung cancer seen in the world, and identifying genetic markers is essential for predicting the prognosis of lung adenocarcinoma and improving treatment outcomes. It is well known that alterations in circadian rhythms are associated with a higher risk of cancer. Moreover, circadian rhythms play a regulatory role in the human body. Therefore, studying the changes in circadian rhythms in cancer patients is crucial for optimizing treatment. The gene expression data and clinical data were sourced from TCGA database, and we identified the circadian clock-related genes. We used the obtained TCGA-LUAD data set to build the model, and the other 647 lung adenocarcinoma patients' data were collected from two GEO data sets for external verification. A risk score model for circadian clock-related genes was constructed, based on the identification of 8 genetically significant genes. Based on ROC analyses, the risk model demonstrated a high level of accuracy in predicting the overall survival times of lung adenocarcinoma patients in training folds, as well as external data sets. This study has successfully constructed a risk model for lung adenocarcinoma prognosis, utilizing circadian rhythm as its foundation. This model demonstrates a dependable capacity to forecast the outcome of the disease, which can further guide the relevant mechanism of lung adenocarcinoma and combine behavioral therapy with treatment to optimize treatment decision-making.

Circadian Rhythm and Nitrogen Metabolism Participate in the Response of Boron Deficiency in the Root of Brassica napus.

Boron (B) deficiency has been shown to inhibit root cell growth and division. However, the precise mechanism underlying B deficiency-mediated root tip growth inhibition remains unclear. In this study, we investigated the role of BnaA3.NIP5;1, a gene encoding a boric acid channel, in Brassica napus (B. napus). BnaA3.NIP5;1 is expressed in the lateral root cap and contributes to B acquisition in the root tip. Downregulation of BnaA3.NIP5;1 enhances B sensitivity in B. napus, resulting in reduced shoot biomass and impaired root tip development. Transcriptome analysis was conducted on root tips from wild-type B. napus (QY10) and BnaA3.NIP5;1 RNAi lines to assess the significance of B dynamics in meristematic cells during seedling growth. Differentially expressed genes (DEGs) were significantly enriched in plant circadian rhythm and nitrogen (N) metabolism pathways. Notably, the circadian-rhythm-related gene HY5 exhibited a similar B regulation pattern in Arabidopsis to that observed in B. napus. Furthermore, Arabidopsis mutants with disrupted circadian rhythm (hy5/cor27/toc1) displayed heightened sensitivity to low B compared to the wild type (Col-0). Consistent with expectations, B deficiency significantly disrupted N metabolism in B. napus roots, affecting nitrogen concentration, nitrate reductase enzyme activity, and glutamine synthesis. Interestingly, this disruption was exacerbated in BnaA3NIP5;1 RNAi lines. Overall, our findings highlight the critical role of B dynamics in root tip cells, impacting circadian rhythm and N metabolism, ultimately leading to retarded growth. This study provides novel insights into B regulation in root tip development and overall root growth in B. napus.

The clockwork of champions: Influence of circadian biology on exercise performance.

Exercise physiology and circadian biology are distinct and long-standing fields. Recently they have seen increased integration, largely due to the discovery of the molecular components of the circadian clock and recognition of human exercise performance differences over time-of-day. Circadian clocks, ubiquitous in cells, regulate a daily tissue specific program of gene expression that contribute to temporal patterns of physiological functions over a 24-h cycle. Understanding how circadian clock function in skeletal muscle, as well as other tissues contribute to exercise performance is still in the very early stages. This review provides background on this emerging field with a review of early exercise and time-of-day studies in both human and animals. We then move into the role of the circadian clock and its daily program of gene expression in skeletal muscle with a focus on specific metabolic and physiological outputs that vary over time-of-day. Lastly, we discuss the recognition that the timing of exercise communicates with the skeletal muscle circadian clock to adjust its phase settings and why this maybe important for performance and health.

A Comparison of 06:00 AM Versus 09:00 AM Serum Cortisol as a Basal Morning Cortisol in Guwahati, Assam: A Pilot Study.

Introduction: Cortisol secretion is regulated by circadian rhythm, which is influenced by zeitgebers like light. In India, the entire country operates under a single time zone, Indian Standard Time, which may not align with the local sunrise timing across different regions. Aims: This study aimed to compare the basal serum cortisol levels between 06:00 AM and 09:00 AM in Guwahati, Assam, where sunrise occurs earlier compared with the western part of the country. A cross-sectional pilot study was conducted from December 2022 to June 2023 in a tertiary care hospital in Guwahati. Methods: Serum cortisol samples were collected at 06:00 AM and 09:00 AM from 25 healthy adult participants once in winter and again in summer. Descriptive statistics and paired Student's t-tests were used. Results: The mean serum cortisol levels at 06:00 AM in winter, summer and overall were 13.2, 13.4 and 13.3 µg/dL, respectively. At 09:00 AM, the mean serum cortisol levels in winter, summer and overall were 8.2, 7.7 and 8.0 µg/dL, respectively. Significant differences were observed between the 06:00 AM and 09:00 AM cortisol levels in both winter and summer (P <0.001). Conclusion: This study highlights the importance of considering the influence of earlier sunrise on circadian rhythm, cortisol secretion and sampling protocols. Recognising the impact of earlier sunrise on cortisol secretion and adapting sampling protocols accordingly to align with the local sunrise can provide a more accurate assessment of basal cortisol levels and help avoid potential misinterpretation and diagnostic challenges associated with low values.

The optimal measurement period of actigraphy for circadian rhythm in relation to adiposity: A retrospective case-control study.

BACKGROUND: This study focused on the relationship between adiposity and Rest-Activity Rhythms (RAR), utilizing both parametric cosine-based models and non-parametric algorithms. The emphasis was on the impact of varying measurement periods (7-28 days) on this relationship. METHODS: We retrieved actigraphy data from two datasets, encompassing a diverse cohort recruited from an obesity outpatient clinic and a workplace health promotion program. Participants were required to wear a research-grade wrist actigraphy device continuously for a minimum of four weeks. The final dataset included 115 individuals (mean age 40.7 ± 9.5 years, 51 % female). We employed both parametric and non-parametric methods to quantify RAR using six standard variables. Additionally, the study evaluated the correlations between three key adiposity indices - Body Mass Index (BMI), Visceral Adipose Tissue (VAT) area, and Body Fat Percentage (BF%) - and circadian rhythm indicators, controlling for factors like physical activity, age, and gender. RESULTS: The obesity group displayed a significantly lower relative amplitude (RA) as per non-parametric algorithm findings, with a decreased amplitude noted in the parametric algorithm analysis, in comparison to the overweight and control groups. The relationship between circadian rhythm indicators and adiposity metrics over 7- to 28-day periods was examined. A notable negative correlation was observed between RA and both BMI and VAT, while correlation coefficients between adiposity indicators and non-parametric circadian parameters increased with extended durations of actigraphy data. Specifically, RA over a 28-day period was significantly correlated with BF%, a trend not seen in the 7-day measurement (p = 0.094) in multivariate linear regression. The strength of the correlation between BF% and 28-day RA was more pronounced than that in the 7-day period (p = 0.044). However, replacing RA with amplitude as per parametric cosinor fitting yielded no significant correlations for any of the measurement periods. CONCLUSION: The study concludes that a 28-day measurement period more effectively captures the link between disrupted circadian rhythms and adiposity. Non-parametric algorithms, in particular, were more effective in characterizing disrupted circadian rhythms, especially when extending the measurement period beyond the standard 7 days.

Effect of time of day on outcomes in elective surgery: a systematic review.

BACKGROUND: The timing of elective surgery could affect clinical outcome because of diurnal rhythms of patient physiology as well as surgical team performance. Waiting times for elective surgery are increasing in many countries, leading to increasing interest in undertaking elective surgery in the evening or at night. We aimed to systematically review the literature on the effect of the timing of elective (but not urgent or emergency) surgery on mortality, morbidity and other clinical outcomes. METHODS: We searched databases for relevant studies combining the terms 'circadian rhythm' and 'anaesthesia/surgery'. Additional relevant articles were found by hand-searching the references. All studies were screened for bias. Included studies examined daytime vs. evening/night-time surgery, morning vs. afternoon surgery, multiple timeslots or used time as a continuous variable. RESULTS: Nineteen retrospective cohort studies, one prospective cohort study and one randomised controlled trial were included (n = 798,914). Evening/night-time elective surgery was associated with a higher risk of mortality when compared with daytime procedures in three studies (n = 611,230), with odds ratios (95%CI) for mortality ranging from 1.35 (1.16-1.56) to 3.98 (1.54-10.30), while no differences were found in three other studies (n = 142,355). No differences were found for morning vs. afternoon surgery (four studies, n = 3277). However, most studies had a low quality of evidence due to their retrospective nature and because not all studies corrected for patient characteristics. Moreover, the studies were heterogeneous in terms of the reported time slots and clinical outcomes. CONCLUSIONS: We found that evening/night-time elective surgery is associated with a higher risk of mortality compared with daytime surgery. However, the quality of evidence was graded as low, and thus, future prospective research should publish individual patient data and standardise outcome measures to allow firm conclusions and facilitate interventions.

Association between PER and CRY gene polymorphisms and the response to caffeine citrate treatment in infants with apnea of prematurity.

Background: Circadian rhythms impact metabolism and the therapeutic effects of drugs. The purpose of this study was to determine the association between PER and CRY polymorphisms and caffeine citrate treatment response in infants with apnea of prematurity. Methods: A total of 221 preterm infants of gestational age <34 weeks were included in this study (160 in the response group and 61 in the non-response group). The propensity score matching method was used to perform a 1:1 matching for all premature infants, and the general characteristics and clinical outcomes of the two groups were compared. The association between polymorphisms of the circadian transcription repressors PER and CRY and caffeine citrate treatment response in infants with apnea of prematurity was analyzed with co-dominant, dominant, recessive, and over-dominant models, as well as analysis of alleles. Generalized multifactor dimensionality reduction (GMDR) analysis was used to analyze the interaction between the PER and CRY genes. Results: After propensity score matching, 45 preterm infants were included in each of the response and non-response groups, and there were no statistically significant differences in general characteristics between the two groups (P > 0.05). Infants in the non-response groups had a higher incidence of moderate and severe bronchopulmonary dysplasia (BPD) (P = 0.043), retinopathy of prematurity (ROP) (P = 0.035), and invasive ventilation (P = 0.027), and their duration of oxygen use (P = 0.041) was longer. When corrected for false discovery rate, the PER3 rs228669 recessive model (P FDR = 0.045) and the over-dominant model (P FDR = 0.045) were both associated with caffeine citrate treatment response. Preterm infants with the rs228669 CC genotype had a significantly lower rate of caffeine citrate non-response in the recessive model (OR = 0.28, 95% CI = 0.12-0.66), which was significantly higher in preterm infants with the CT genotype in the over-dominant model (OR = 4.18, 95% CI = 1.64-10.66). GMDR analysis revealed an interaction between the PER and CRY genes (P < 0.05). Conclusions: Circadian rhythms may play a role in the response of premature infants to caffeine citrate, and polymorphisms of the PER and CRY genes may influence the effectiveness of caffeine citrate treatment for apnea of prematurity.

Chronobiological variation in takotsubo syndrome: an updated systematic review and meta-analysis.

Takotsubo syndrome (TTS) might exhibit particular chronobiological patterns in its onset, characterized by variations according to time of the day, day of the week, and month of the year. The aim of this study was to fully explore the temporal patterns (circadian, weekly and seasonal) in the onset of TTS. A systematic review and meta-analysis of literature were conducted for studies (2006-2024) reporting the temporal patterns (circadian, weekly and/or seasonal) in the onset of TTS. Among the 4257 studies retrieved, 20 (including 64,567 subjects) fulfilled all eligibility criteria. Data were aggregated used random effects model as pooled risk ratio and the attributable risk (AR). The proportion analysis (including 8 studies; n=853) showed a decreasing pattern of the pooled rates of TTS shifting from the morning to the night (pooled TTS rates: 34.0%; 32.1%; 21.7%; 12.7% in the morning, afternoon, evening and night, respectively). The same pattern was observed stratifying by type of preceding stressful factor or event, considering physical stressors (pooled rates in the morning and night: 37.6% and 9.8%, respectively), and also in case no event could be identified. The pooled rates of TTS onset peaked on Monday and Tuesday (17.3% and 18.4% respectively), then declined during the week, reaching the lowest rates on Friday and Saturday (10.6% and 10.8%, respectively), with no sex differences. TTS onset reached the highest values on summer, and the lowest in winter (27.9% versus 21.7% in summer and winter, respectively). The TTS morning peak based analyses (∼33% of all the registered events) account for a RR of 1.46 (95% CI: 1.38-1.54), the week-based for a RR of 1.26 (1.16-1.35), the season-based for a RR of 1.04 (1.04-1.05). TTS onset exhibits specific chronobiological patterns, characterized by a peak during the morning hours, and on Monday and Tuesday. Differing from other cardiovascular emergencies TTS was more frequent during summer. Further studies are needed to fully understand the underlying pathophysiological mechanisms in order to tailor relative management and preventive strategies.

Combined effects of sleep timing and nighttime sleep duration on non-alcoholic fatty liver disease.

BACKGROUND: While short sleep duration is linked to higher risk of non-alcoholic fatty liver disease (NAFLD), the combined effects of sleep timing and sleep duration on NAFLD are less explored. METHODS: In this cross-sectional study of 39,471 participants from Beijing-Tianjin-Hebei region of China, self-reported sleep information and ultrasonography-diagnosed NAFLD were obtained from Jan 2018 to Jan 2020. Sleep timing was categorized based on sleep midpoint: early-type (before 2:00 AM), intermediate-type (2:00-2:30 AM), and late-type (after 2:30 AM). We used multivariable logistic regression to explore the relationship between sleep timing, duration, and NAFLD. We analyzed sleep midpoint and duration categorically and continuously, and conducted stratification analyses by age, sex, body mass index, hypertension, diabetes, and dyslipidemia. RESULTS: Intermediate-type (OR: 1.15, 95% confidence interval: 1.05-1.26) and late-type sleep timing (OR: 1.08, 1.00-1.16) were associated with higher NAFLD risk compared to early-type. Additionally, longer sleep duration was linked to lower risk (OR: 0.92, 0.90-0.95 per hour increase). Notably, intermediate to late-type sleepers with normal sleep duration (7 to <8 h) exhibited a 20% higher NAFLD risk compared to early-type sleepers with the same duration (OR: 1.20, 1.04-1.39). The increased NAFLD risk associated with intermediate to late sleep timing was particularly evident in men, hypertension, and prediabetes or diabetes participants. CONCLUSIONS: Intermediate to late sleep timing, even with normal sleep duration, is associated with increased NAFLD risk. These findings underscore the importance of considering both sleep timing and sleep duration for NAFLD prevention, especially in men and individuals with cardiometabolic conditions.