The Sleep-E Study: An on-going cross-sectional study investigating associations of sleep quality and cardio-metabolic risk factors

Abstract

Short sleep duration (⩽5-6 h/night) has been associated with an increased risk of weight gain (1,2) and non-communicable disease (3). Recently, through a systematic review and meta-analysis, we identified that short sleep duration may induce positive energy balance and have implications on weight gain over the long term (Al Khatib et al, unpublished data). Quality of sleep, opposed to its duration, has not been extensively reported in the context of the impact on disease risk. While self-reported measures of sleep quality have been linked to markers of adiposity and insulin resistance (4), there are no reports of objective measures of sleep quality in free-living conditions and cardio-metabolic disease risk. The Sleep-E Study is an on-going, cross-sectional study assessing associations between objective measures of sleep and cardio-metabolic risk factors in healthy adults, aged 18-55 years (N = 29; 12M/17 F). It is being conducted in accordance with the Declaration of Helsinki. Sleep parameters were assessed using the MotionWatch8 (CamNtech Ltd, Cambridge, UK) for six continuous nights, using sleep latency (time taken to transition from wakefulness to sleep) and sleep efficiency (actual sleep time expressed as a percentage of time in bed) as indicators of sleep quality. Fasting blood samples, blood pressure and anthropometric measurements were taken on study day 1. Correlations between sleep quality indicators and cardiometabolic risk factors, adjusted for age, sex and BMI, were investigated.These data show a strong negative correlation between sleep efficiency and TG concentrations and a moderate positive correlation with TC:HDL ratios. Similarly, sleep latency was moderately and positively correlated with both triglyceride concentrations and TC: HDL ratios. Sleep duration did not correlate with any risk factors. This cross-sectional data suggests that compromised sleep quality is linked to lipid metabolism. Sleep quality, independent of sleep duration, may be a potential, novel target for cardio-metabolic disease prevention. This cross-sectional study demonstrates the need for intervention studies assessing the relationship between sleep quality and cardio-metabolic risk.

Chrono‐nutrition – an emerging, modifiable risk factor for chronic disease?

“…Jakubowicz et al found similar results in 93 women with overweight or obesity and showed beneficial effects of high caloric intake at breakfast compared with in the evening in terms of weight loss, waist circumference, serum ghrelin and lipids, appetite scores and insulin resistance indices (Jakubowicz et al, 2013). Other studies have shown the importance of meal frequency and/ or meal irregularity for cardiometabolic health (Farshchi et al, 2004;Farshchi et al, 2005;Madjd et al, 2016;Pot et al, 2016).…”

“…First, they demonstrated in a systematic review and meta‐analysis of human intervention studies that partial sleep deprivation resulted in increased energy intake but not increased energy expenditure, leading to a net positive energy balance of 385 kcal/day (Al Khatib et al, 2017). Subsequently, they showed in a pilot cross‐sectional study ( Sleep‐E study) that sleep quality is linked to lipid metabolism (Al Khatib et al, 2016). Lastly, they showed that sleep extension is a feasible lifestyle intervention in free‐living, habitual short sleepers in a randomised controlled trial ( SLuMBER study) (Al Khatib et al, 2018).…”

“…Over the past decade, nutrition researchers have incorporated research of biological temporal rhythms, chrono-biology, into nutrition research, and this novel area of nutrition research is called chrono-nutrition (Garaulet & Gómez-Abellán, 2014;St-Onge et al, 2017;Tahara & Shibata, 2013). Chrono-nutrition includes research into the distribution of energy intake, meal frequency and regularity, the duration of eating and fasting periods, and the relative importance of these factors for metabolic health and chronic disease risk (Flanagan et al, 2020;Pot et al, 2016). This Virtual Issue brings together papers recently published in Nutrition Bulletin discussing different aspects of chrono-nutrition, including sleep, breakfast consumption and time-restricted feeding (Figure 1) (Clayton et al, 2020;Darzi et al, 2017;Edinburgh et al, 2017;Gibson, 2018;Gibson-Moore & Chambers, 2019;Lynch et al, 2021;Ruddick-Collins et al, 2018).…”

Sleep patterns in relation to dietary patterns and cardio‐metabolic risk: An update from Drummond Pump Priming Award recipients

“…Sleep-E is a pilot cross-sectional study to investigate the association between energy balance, dietary intake, cardio-metabolic risk factors and body composition with objective measures of sleep duration and quality in healthy adults (Al Khatib et al 2016b). We hypothesised that short sleep duration and/or poor sleep quality would be associated with higher EI and poorer diet quality and habits.…”