Time in bed,sleep quality and associations with cardiometabolic markers in children: the Prevention and Incidence of Asthma and Mite Allergy birth cohort study

We investigated associations of time in bed and multiple sleep quality characteristics with cardiometabolic markers in children. Data from the prevention and incidence of asthma and mite allergy study, a population‐based prospective birth‐cohort study started in 1996–1997 in the Netherlands, were analysed. In total 1481 children aged 11–12 years completed a questionnaire (including questions on sleep) and underwent a medical examination. We measured body mass index, waist circumference, total‐ and high‐density lipoprotein cholesterol, blood pressure and glycated haemoglobin. Results showed that in girls, some sleep characteristics were related to anthropometrics (body mass index, waist circumference) and cholesterol. Girls who had a long time in bed (11–12.5 h) had 0.16 lower body mass index z‐score (95% confidence interval ?0.31; ?0.01) and 0.99 cm smaller waist circumference (95% confidence interval ?2.01; ?0.13) compared with girls who spent 10–10.5 h in bed. Girls who went to bed late and rose early had 0.16 mm higher total cholesterol (95% confidence interval 0.01; 0.31) and 0.08 mm higher high‐density lipoprotein cholesterol (95% confidence interval 0.01; 0.14) than ‘early to bed/early rise’ girls. Girls with night‐time awakenings had 0.14 mm higher total cholesterol (95% confidence interval 0.03; 0.25) than girls without night‐time awakenings. Girls who felt sleepy/tired ≥1 day per week had 0.10 mm lower high‐density lipoprotein cholesterol (95% confidence interval ?0.16; ?0.04) and 0.17 mm higher total cholesterol/high‐density lipoprotein cholesterol ratio (95% confidence interval 0.02; 0.32) than girls who did not feel sleepy. No associations were found for boys. Sleep characteristics were not related to blood pressure and glycated haemoglobin, and effect sizes of the associations in girls were small. Therefore, we consider it premature to propose that improved sleep could reduce cardiovascular risk during childhood.     

Areas of brain activation in males and females during viewing of erotic film excerpts

Various lines of evidence indicate that men generally experience greater sexual arousal (SA) to erotic stimuli than women. Yet, little is known regarding the neurobiological processes underlying such a gender difference. To investigate this issue, functional magnetic resonance imaging was used to compare the neural correlates of SA in 20 male and 20 female subjects. Brain activity was measured while male and female subjects were viewing erotic film excerpts. Results showed that the level of perceived SA was significantly higher in male than in female subjects. When compared to viewing emotionally neutral film excerpts, viewing erotic film excerpts was associated, for both genders, with bilateral blood oxygen level dependent (BOLD) signal increases in the anterior cingulate, medial prefrontal, orbitofrontal, insular, and occipitotemporal cortices, as well as in the amygdala and the ventral striatum. Only for the group of male subjects was there evidence of a significant activation of the thalamus and hypothalamus, a sexually dimorphic area of the brain known to play a pivotal role in physiological arousal and sexual behavior. When directly compared between genders, hypothalamic activation was found to be significantly greater in male subjects. Furthermore, for male subjects only, the magnitude of hypothalamic activation was positively correlated with reported levels of SA. These findings reveal the existence of similarities and dissimilarities in the way the brain of both genders responds to erotic stimuli. They further suggest that the greater SA generally experienced by men, when viewing erotica, may be related to the functional gender difference found here with respect to the hypothalamus.     

Brain activity during emotionally negative pictures in schizophrenia with and without flat affect: an fMRI study

The aim of this functional magnetic resonance imaging (fMRI) study was to compare regional brain activity in schizophrenia subjects with (FA+) and without (FA-) flat affect during the viewing of emotionally negative pictures. Thirteen FA+ subjects and 11 FA- subjects were scanned while being presented with a series of emotionally negative and neutral pictures. Experientially, the viewing of the negative pictures induced a negative emotional state whose intensity was significantly greater in the FA- group than in the FA+ group. Neurally, the Negative minus Neutral contrast revealed, in the FA- group, significant loci of activation in the midbrain, pons, anterior cingulate cortex, insula, ventrolateral orbitofrontal cortex, anterior temporal pole, amygdala, medial prefrontal cortex, and extrastriate visual cortex. In the FA+ group, this contrast produced significant loci of activation in the midbrain, pons, anterior temporal pole, and extrastriate visual cortex. When the brain activity measured in the FA+ group was subtracted from that measured in the FA- group, only the lingual gyrus was significantly activated. Perhaps in FA+ subjects an amygdaloid malfunction rendered the amygdala unable to correctly evaluate the emotional meaning of the pictures presented, thus preventing effective connectivity linking the amygdala to the brain regions implicated in the physiological and experiential dimensions of emotion. Alternatively, a disturbance of effective connectivity in the neural networks linking the midbrain and the medial prefrontal system may have been responsible for the quasi absence of emotional reaction in FA+ subjects, and the abnormal functioning of the medial prefrontal cortex and anterior cingulate cortex in the FA+ group.     

Reported versus measured body weight and height of 4-year-old children and the prevalence of overweight

BACKGROUND: In adults, body weight tends to be underestimated when based on self-reported data. Whether this discrepancy between measured and reported data exists in healthy young children is unclear. We studied whether parental reported body weight and height of 4-year-old children corresponded with measured body weight and height. In addition, we studied the determinants and the consequences of differences between reported and measured data. METHODS: Data on body weight and height of 864 4-year-old Dutch children born in 1996/1997 enrolled in the Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort study were collected via a questionnaire and a medical examination. Overweight was defined according to standard international age and gender specific definitions. RESULTS: Mean differences between measured and reported body weight, height, and body mass index (BMI) were small. Parents of children with a low BMI tended to over report body weight while parents of children with a high BMI tended to underreport body weight. Whereas 9.5% of the children were overweight according to reported BMI, the prevalence of overweight was 13.4% based on measured BMI. Over 45% of the overweight children according to measured BMI were missed when reported BMI was used. CONCLUSION: These findings suggest that overweight prevalence rates in children are underestimated when based on reported weight and height.     

Traffic-related air pollution, preterm birth and term birth weight in the PIAMA birth cohort study

Background

Maternal exposure to air pollution has been associated with adverse pregnancy outcomes. Few studies took into account the spatial and temporal variation of air pollution levels.

Objectives

To evaluate the impact of maternal exposure to traffic-related air pollution during pregnancy on preterm birth and term birth weight using a spatio-temporal exposure model.

Methods

We estimated maternal residential exposure to nitrogen dioxide (NO₂), particulate matter (PM_2.5) and soot during pregnancy (entire pregnancy, 1st trimester, and last month) for 3853 singleton births within the Dutch PIAMA prospective birth cohort study by means of temporally adjusted land-use regression models. Associations between air pollution concentrations and preterm birth and term birth weight were analyzed by means of logistic and linear regression models with and without adjustment for maternal physical, lifestyle, and socio-demographic characteristics.

Results

We found positive, statistically non-significant associations between exposure to soot during entire pregnancy and during the last month of pregnancy and preterm birth [adj. OR (95% CI) per interquartile range increase in exposure 1.08 (0.88–1.34) and 1.09 (0.93–1.27), respectively]. There was no indication of an adverse effect of air pollution exposure on term birth weight.

Conclusions

In this study, maternal exposure to traffic-related air pollution during pregnancy was not associated with term birth weight. There was a tendency towards an increased risk of preterm birth with increasing air pollution exposure, but statistical power was low.