Associations Between Chrononutrition With Sleep Quality and Melatonin Rhythm of Pregnant Women

Objectives Chrononutrition is referred to as a zeitgeber for its ability to synchronize the circadian rhythm. In addition to the role as circadian marker, sleep and melatonin are important factors for optimal maternal and infant outcomes. Understanding the chrononutrition factors associated with sleep quality and melatonin rhythm during pregnancy has practical importance for preventive care. Hence, this study aimed to examine the association between chrononutrition with sleep quality and melatonin rhythm during pregnancy. Methods A total of 114 primigravidas were recruited at randomly selected government maternal and child clinics in Kuala Lumpur, Malaysia. Gestational age and pre-pregnancy body mass index (BMI) were extracted from clinic records. Components of chrononutrition including meal timing, meal frequency, eating window, breakfast skipping, and night eating were assessed using 3-day food record. Sleep quality in the third trimester was determined using Pittsburgh Sleep Quality Index (PSQI). Subsample (n = 48) provided salivary samples at 4 time-points (9:00, 15:00, 21:00 and 3:00 h) over 24 hours for melatonin assay. Results The mean gestational age of participants was 33.0 (2.1) weeks; 13% were underweight and 22% were overweight/obese before pregnancy. Average daily meal frequency was 4.1 (0.9). The majority (68%) practiced a shorter eating window (≤12 hours); 25% skipped breakfast and 19% ate within 2 hours pre-bedtime. The prevalence of poor sleep among the participants was 56%. Mean salivary melatonin level was 19.6 (16.3) pmol/L. In the adjusted linear regression model, lower meal frequency and fat intake during dinner were significant predictors of poor sleep quality (β = −0.266, P = 0.035 and β = −0.232, P = 0.026, respectively). Eating nearer to bedtime was significantly associated with greater deviation of melatonin acrophase from mid-sleep clock time (β = −0.339, P = 0.043). Conclusions Findings suggested that unfavorable characteristics of chrononutrition may contribute to poor sleep and misalignment of melatonin phase. Components of chrononutrition may be incorporated into meal intervention to improve maternal sleep quality and circadian health. Funding Sources Research relating to this abstract was funded by the Ministry of Education Malaysia Fundamental Research Grant.

Effects of general versus regional anaesthesia on circadian melatonin rhythm and its association with postoperative delirium in elderly patients undergoing hip fracture surgery: study protocol for a prospective cohort clinical trial

IntroductionPostoperative delirium (POD) is a common neurological complication after hip fracture surgery and is associated with high morbidity and mortality in elderly patients. Although the specific mechanism of POD remains unclear, circadian rhythm disruptions have recently drawn increased attention. To date, only limited postoperative time points of plasma melatonin level measurements were recorded in previous studies, and such data cannot represent a comprehensive melatonin rhythm. The process of anaesthesia (either general anaesthesia (GA) or regional anaesthesia (RA)) is known to influence the melatonin rhythm. However, how these two anaesthesia methods differently affect the postoperative melatonin rhythm is still unknown. Therefore, we hypothesise that RA may attenuate the disruption of the melatonin rhythm, which might decrease the incidence of POD in elderly patients undergoing hip surgery.Methods and analysisIn this prospective cohort clinical trial, 138 patients scheduled for hip fracture surgery will be divided into two groups to receive either GA or RA. The primary aim is to compare the circadian rhythm of melatonin secretion between the two groups and explore its association with the incidence of POD.Ethics and disseminationThe study has been approved by the Medical Science Research Ethics Committees of Beijing Jishuitan Hospital (JLKS201901-04). The results of the study will be published in peer-reviewed international journals.Trial registration numberChiCTR1900027393.