Sleep duration and plasma leptin concentrations in early pregnancy among lean and overweight/obese women: a cross sectional study

Sleep duration, napping behaviors and restless legs syndrome during pregnancy and the trajectories of ultrasonographic measures of fetal growth: Findings from the NICHD Fetal Growth Studies-Singletons

OBJECTIVES

Given the plausible mechanisms and the lacking of empirical evidence, the study aims to investigate how gestational sleep behaviors and the development of sleep disorders, such as restless legs syndrome, influence ultrasonographic measures of fetal growth.

METHODS

The study included 2457 pregnant women from the NICHD Fetal Growth Studies - Singletons (2009-2013), who were recruited between 8-13 gestational weeks and followed up to five times during pregnancy. Women were categorized into six groups based on their total sleep hours and napping frequency. The trajectory of estimated fetal weight from 10-40weeks was derived from three ultrasonographic measures. Linear mixed effect models were applied to model the estimated fetal weight in relation to self-reported sleep-napping behaviors and restless legs syndrome status, adjusting for age, race and ethnicity, education, parity, prepregnancy body mass index category, infant sex, and prepregnancy sleep-napping behavior.

RESULTS

From enrollment to near delivery, pregnant women's total sleep duration and nap frequency declined and restless legs syndrome symptoms frequency increased generally. No significant differences in estimated fetal weight were observed by sleep-napping group or by restless legs syndrome status. Results remained similar in sensitivity analyses and stratified analyses by women's prepregnancy body mass index category (normal vs. overweight/obese) or by infant sex.

CONCLUSIONS

Our data indicate that there is no association between sleep during pregnancy-assessed as total sleep duration and napping frequency, nor restless legs syndrome symptoms-and fetal growth from weeks 10 to 40 in healthy pregnant women.

Neutrophil degranulation, endothelial and metabolic dysfunction in unvaccinated long COVID patients

BACKGROUND

Long COVID symptoms are widely diffused and have a poorly understood pathophysiology, with possible involvement of inflammatory cytokines.

MATERIALS AND METHODS

A prospective follow-up study involved 385 unvaccinated patients, started 1 month after SARS-CoV-2 infection and continued for up to 12 months. We compared circulating biomarkers of neutrophil degranulation, endothelial and metabolic dysfunction in subjects with long COVID symptoms and in asymptomatic post-COVID controls.

RESULTS

The highest occurrence of symptoms (71%) was after 3 months from the infection, decreasing to 62.3% and 29.4% at 6 and 12 months, respectively. Compared to controls, long COVID patients had increased levels of the neutrophilic degranulation indices MMP-8 and MPO, of endothelial dysfunction indices L-selectin and P-selectin. Among indices of metabolic dysfunction, leptin levels were higher in long COVID patients than in controls.

CONCLUSION

In unvaccinated patients, symptoms may persist up to 1 year after acute COVID infection, with increased indices of neutrophil degranulation, endothelial and metabolic dysfunction. The clinical implications of specific inflammatory biomarkers require further attention, especially in individuals with fatigue and long COVID-linked cognitive dysfunctions.

Effects of Gestational Sleep Patterns and Their Changes on Maternal Glycemia and Offspring Physical Growth in Early Life

Maternal sleep patterns during pregnancy are drawing increased attention to examine its role in the regulation of maternal glycemia and physical growth of offspring within 24 months. Among 3329 eligible mother−child pairs included in the Shanghai Maternal−Child Pairs Cohort, sleep patterns of pregnant women were assessed by Pittsburgh Sleep Quality Index and objective measurement in early and late pregnancy. Offspring physical growth within 24 months was primarily indicated by the body mass index Z-score (BAZ), catch-up growth, and overweight/obesity. In total, 3329 and 382 pregnant women were included with subjectively assessed and objectively measured sleep pattern, respectively. The increased risk of GDM was associated with maternal night-time sleep duration ≥8.5 h in early pregnancy, or sleep quality change from poor to good during pregnancy (OR = 1.48; 95% CI, 1.06 to 2.07). In the GDM group, the effect of sleep duration in early pregnancy on overweight/obesity in offspring within 24 months showed a U-shaped curve, with a 1.73-fold and 1.43-fold increased risk of overweight/obesity of offspring in pregnant women with <7.5 or ≥8.5 h of sleep duration, respectively. A good gestational sleep pattern was required to reduce the risk of GDM and offspring overweight/obesity within 24 months.

Association between sleep duration during pregnancy and preterm birth: a dose-response meta-analysis

OBJECTIVE

Preterm birth is now a global health problem. There is a great alteration of sleep duration in pregnancy. Whether sleep duration in pregnancy affects preterm birth remains unclarified. This study aimed to examine the associations of sleep duration on preterm birth risk based on the dose-response meta-analysis.

MATERIALS AND METHODS

Electronic databases (PubMed, Web of Science, and Ovid) were searched for relevant studies from database inception to September 2020. Studies describing the associations of maternal sleep duration with preterm birth risk were included. A random-effects model was adopted to calculate the summarized relative risk (SRR) and 95% confidence intervals (CIs) as the effect sizes for all studies. Moreover, dose-response analysis was used for combining studies that used categories of sleep duration as exposure. In addition, subgroup analysis and meta-regression analysis were conducted to adjust potential confounders and investigate the source of heterogeneity.

RESULTS

A total of 3771 unique studies were screened, and eight cohort studies and one case-control study were identified, with a total of 2000 preterm birth cases. Pooled data indicated that extreme sleep duration (short sleep duration or long sleep duration) in pregnancy was closely related to preterm birth in comparison with normal sleep duration (SRR = 1.13, 95%CI: 1.05-1.22) and there was no significant heterogeneity among studies (I² = 7.0%, p = .37). Begg's funnel plot failed to uncover any evidence of publication bias. The non-linearity in the association of sleep duration with preterm birth showed significance (p < .01). Considering pregnant women slept for 7 h as a reference, 4 h short sleepers had a higher predicted risk of preterm birth (RR = 1.10, 95%CI: 1.01-1.19). Additionally, as compared with women with normal sleep duration, the preterm birth risk with short sleep durations (SRR = 1.20, 95%CI: 1.05-1.37) was elevated among pregnant women, and long sleep duration was related to preterm birth after adjusting for age (SRR = 1.20, 95%CI: 1.01-1.42).

CONCLUSION

There is an association of extreme sleep duration in pregnancy with preterm birth. In a non-linear dose-response meta-analysis, a U-shaped relationship between sleep duration and risk of preterm birth was observed and pregnant women who slept 4 h/day had a significantly higher risk of preterm birth than those who slept normally.

Physical activity and sleep duration during pregnancy have interactive effects on caesarean delivery: a population-based cohort study in Tianjin, China

Background

There were inconsistent findings in the literature regarding the associations of physical activity and sleep duration during pregnancy with caesarean delivery for different reasons. It was also unknown whether physical activity and sleep duration during pregnancy had interactive effects on the risks of different types of caesarean delivery. The study aimed to investigate the effects of physical activity, sleep duration and their interactions on the risk of caesarean delivery for medical reasons and non-medical reasons.

Methods

From October 2010 to August 2012, a prospective population-based cohort of 13,015 pregnant women was established in six central urban districts of Tianjin, China. Pregnancy outcomes were retrieved from an electronic database and caesarean delivery was divided into caesarean delivery for medical reasons and caesarean delivery for non-medical reasons. Physical activity and sleep status were collected at 24–28 weeks of gestation using self-reported questionnaires. Logistic regression and additive interaction were used to examine physical activity, sleep duration and their interactive effects on risk of caesarean delivery.

Results

In the cohort, 5692 (43.7%) and 2641 (20.3%) of women had caesarean delivery for medical reasons and non-medical reasons, respectively. Low physical activity increased the risk of caesarean delivery for medical reasons (adjusted OR: 1.13, 95%CI 1.04–1.23) but not caesarean delivery for non-medical reasons. Sleep duration < 7 h/day and poor sleep quality were not associated with caesarean delivery. Sleep duration ≥9 h/day increased the risk of caesarean delivery for medical reasons (1.12, 1.02–1.22) and caesarean delivery for non-medical reasons (1.16, 1.05–1.29). Co-presence of low physical activity and sleep duration ≥9 h/day increased risk of caesarean delivery (1.25, 1.12–1.41), and their additive interaction was statistically significant for caesarean delivery for medical reasons but not for caesarean delivery for non-medical reasons.

Conclusions

Low physical activity and excessive sleep duration during pregnancy each increased the risk of caesarean delivery, and they had an interactive effect on the risk of caesarean delivery for medical reasons but not on the risk of caesarean delivery for non-medical reasons. Increasing physical activity and maintaining recommended sleep duration during pregnancy may have benefits for perinatal health.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03788-4.

The impact of myo-inositol supplementation on sleep quality in pregnant women: a randomized, double-blind, placebo-controlled study

BACKGROUND

Myo-inositol, a glial marker which plays a critical role in some brain regions, can supposedly affect sleep processes. The purpose of randomized controlled trial was to evaluate the impact of myo-inositol supplementation on sleep quality of pregnant women.

METHODS

The study enrolled 60 women with low risk singleton pregnancies, with a gestational age of at least 14 weeks, in Iran. The participants were block randomized to receive myo-inositol supplementation powder containing 2000 mg of myo-inositol and 200 μg of folic acid or placebo (400 μg of folic acid) for 10 weeks from the gestational age of 14-24. Sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI). The primary outcome was the change in sleep quality from the first trimester to the second trimester (24-28 weeks). The ANCOVA with adjusted covariate variables in the first trimester was conducted to estimate the sleep quality between the two groups.

RESULTS

The results of ANCOVA boot strapped showed that the mean difference of the total sleep quality score between the two groups was -1.537; 95% CI: -3.050 to -0.024, p = .047) in the second trimester at immediately post-intervention. Also, there were significant differences between the two groups in terms of subjective sleep quality (MD: -0.427; 95% CI: -0.725 to -0.128, p = .006, sleep duration (MD: -0.670; 95% CI: -1.240 to -0.101; p = .022) and habitual sleep efficiency (MD: -0.561; 95% CI: -1.038 to -0.085, p = .022).

CONCLUSION

The research confirmed that myo-inositol supplementation can improve global sleep quality, subjective sleep quality, and sleep duration during pregnancy. Therefore, these findings applied to minimize the rate of poor sleep quality in pregnant women.

Positive association of plasma leptin with sleep quality in obese type 2 diabetes patients

AIMS/INTRODUCTION

Poor sleep quality is associated with obesity and diabetes. The adipocyte-derived hormone, leptin, was recently shown to underlie the link between abnormal sleep and obesity. We aimed to investigate the association between leptin and sleep quality in type 2 diabetes patients.

MATERIALS AND METHODS

In the present cross-sectional study, we studied 182 type 2 diabetes patients, among whom 113 were diagnosed with obesity (body mass index ≥25 kg/m2 ). Fasting plasma leptin levels were measured, and sleep architecture was assessed using single-channel electroencephalography.

RESULTS

Using unadjusted analyses, the obese type 2 diabetes patients, but not their non-obese counterparts, showed a positive correlation between plasma leptin levels and a parameter for deep sleep assessed by delta power during the first sleep cycle. Multivariate analysis showed that plasma leptin levels were positively associated with delta power, but not with the total sleep time, after adjusting for potential confounders including age, body mass index and the apnea-hypopnea index, in the obesity group. However, neither delta power nor total sleep time was associated with leptin in the non-obesity group.

CONCLUSIONS

Plasma leptin levels are independently associated with sleep quality in obese, but not in non-obese, type 2 diabetes patients. The present study indicates a favorable relationship between leptin and sleep quality in obese type 2 diabetes patients.

Association between sleep duration during pregnancy and gestational diabetes mellitus: a meta-analysis

OBJECTIVE

Sleep is critical for glucose metabolism. Pregnant women often have sleep disturbances and extreme sleep duration. Investigations of the relationship between sleep duration during pregnancy and gestational diabetes mellitus (GDM) have reported inconsistent results. The present study aimed to meta-analyze the relationship between sleep duration during pregnancy and GDM risk.

METHODS

We performed a systematic search of the PubMed, ISI Web of Science, and PsycINFO databases for studies that were published up to October 2017, that reported associations between sleep duration during pregnancy and GDM risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated as the effect sizes for all studies. Heterogeneity and potential publication biases were assessed.

RESULTS

A total of 4366 papers were retrieved, among which seven studies assessed the relationship between sleep duration during pregnancy and GDM development. The seven articles included 18,203 subjects at baseline and 1294 GDM cases during follow-up. Compared to normal sleep duration, extreme sleep duration during early and middle pregnant stages had a close relationship with GDM based upon pooled data from prospective and cross-sectional studies. Prospective results showed that long sleep duration during pregnancy was a risk factor for GDM, but not short sleep duration. Publication biases were found when analyzing the relationship between extreme sleep duration and GDM.

CONCLUSIONS

Extreme sleep duration during pregnancy is closely associated with GDM. Moreover, long but not short sleep duration can predict the risk of developing GDM. These findings remind us of the importance of sleep duration control during pregnancy and help optimize early strategies for the prevention of GDM.

Activity behaviors in lean and morbidly obese pregnant women

Interventions to increase physical activity in pregnancy are challenging for morbidly obese women. Targeting sedentary behaviors may be a suitable alternative to increase energy expenditure. We aimed to determine total energy expenditure, and energy expended in sedentary activities in morbidly obese and lean pregnant women. We administered the Pregnancy Physical Activity Questionnaire (nonobjective) and the Actical accelerometer (objective) to morbidly obese (BMI ≥ 40 kg/m²) and lean (BMI ≤ 25 Kg/m²) pregnant women recruited in early (<24 weeks), and late (≥24 weeks) gestation. Data are mean (SD). Morbidly obese pregnant women reported expending significantly more energy per day in early (n = 140 vs 109; 3198.4 (1847.1) vs 1972.3 (10284.8) Kcal/d, P < .0001) and late (n = 104 vs 64; 3078.2 (1356.5) vs 1947.5 (652.0) Kcal/d, P < .0001) pregnancy, and expended significantly more energy in sedentary activities, in early (816.1 (423.5) vs 540.1 (244.9) Kcal/d, P < .0001) and late (881.6 (455.4) vs 581.1 (248.5) Kcal/d, P < .0001) pregnancy, than lean pregnant women. No differences were observed in the proportion of energy expended sedentary between lean and morbidly obese pregnant women. The greater total energy expenditure in morbidly obese pregnant women was corroborated by Actical accelerometer in early (n = 14 per group, obese 1167.7 (313.6) Kcal; lean 781.1 (210.1) Kcal, P < .05), and in late (n = 14 per group, obese 1223.6 (351.5) Kcal; lean 893.7 (175.9) Kcal, P < .05) pregnancy. In conclusion, non-objective and objective measures showed morbidly obese pregnant women expended more energy per day than lean pregnant. Further studies are needed to determine whether sedentary behaviors are a suitable target for intervention in morbidly obese pregnancy.

Does Circadian Disruption Play a Role in the Metabolic-Hormonal Link to Delayed Lactogenesis II?

Breastfeeding improves maternal and child health. The American Academy of Pediatrics recommends exclusive breastfeeding for 6 months, with continued breastfeeding for at least 1 year. However, in the US, only 18.8% of infants are exclusively breastfed until 6 months of age. For mothers who initiate breastfeeding, the early post-partum period sets the stage for sustained breastfeeding. Mothers who experience breastfeeding problems in the early post-partum period are more likely to discontinue breastfeeding within 2 weeks. A major risk factor for shorter breastfeeding duration is delayed lactogenesis II (DLII; i.e., onset of milk "coming in" more than 72 h post-partum). Recent studies report a metabolic-hormonal link to DLII. This is not surprising because around the time of birth the mother's entire metabolism changes to direct nutrients to mammary glands. Circadian and metabolic systems are closely linked, and our rodent studies suggest circadian clocks coordinate hormonal and metabolic changes to support lactation. Molecular and environmental disruption of the circadian system decreases a dam's ability to initiate lactation and negatively impacts milk production. Circadian and metabolic systems evolved to be functional and adaptive when lifestyles and environmental exposures were quite different from modern times. We now have artificial lights, longer work days, and increases in shift work. Disruption in the circadian system due to shift work, jet-lag, sleep disorders, and other modern life style choices are associated with metabolic disorders, obesity, and impaired reproduction. We hypothesize that DLII is related to disruption of the mother's circadian system. Here, we review literature that supports this hypothesis, and describe interventions that may help to increase breastfeeding success.

Sleep duration, vital exhaustion, and odds of spontaneous preterm birth: a case-control study

BACKGROUND

Preterm birth is a leading cause of perinatal morbidity and mortality worldwide, resulting in a pressing need to identify risk factors leading to effective interventions. Limited evidence suggests potential relationships between maternal sleep or vital exhaustion and preterm birth, yet the literature is generally inconclusive.

METHODS

We examined the relationship between maternal sleep duration and vital exhaustion in the first six months of pregnancy and spontaneous (non-medically indicated) preterm birth among 479 Peruvian women who delivered a preterm singleton infant (<37 weeks gestation) and 480 term controls who delivered a singleton infant at term (≥37 weeks gestation). Maternal nightly sleep and reports of vital exhaustion were ascertained through in-person interviews. Spontaneous preterm birth cases were further categorized as those following either spontaneous preterm labor or preterm premature rupture of membranes. In addition, cases were categorized as very (<32 weeks), moderate (32-33 weeks), and late (34- <37 weeks) preterm birth for additional analyses. Logistic regression was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

After adjusting for confounders, we found that short sleep duration (≤6 hours) was significantly associated with preterm birth (aOR = 1.56; 95% CI 1.11-2.19) compared to 7-8 hours of sleep. Vital exhaustion was also associated with increased odds of preterm birth (aOR = 2.41; 95% CI 1.79-3.23) compared to no exhaustion (Ptrend <0.001). These associations remained significant for spontaneous preterm labor and preterm premature rupture of membranes. We also found evidence of joint effects of sleep duration and vital exhaustion on the odds of spontaneous preterm birth.

CONCLUSIONS

The results of this case-control study suggest maternal sleep duration, particularly short sleep duration, and vital exhaustion may be risk factors for spontaneous preterm birth. These findings call for increased clinical attention to maternal sleep and the study of potential intervention strategies to improve sleep in early pregnancy with the aim of decreasing risk of preterm birth.