Early Determinants of Childhood Blood Pressure at the Age of 6 Years:The GECKO Drenthe and ABCD Study Birth Cohorts

Background There is still uncertainty about the nature and relative impact of early determinants on childhood blood pressure. This study explored determinants of blood pressure at the age of 6 years in 2 Dutch birth cohorts. Methods and Results Results of hierarchical multiple linear regression analyses in GECKO (Groningen Expert Center for Kids With Obesity) Drenthe study (n=1613) were replicated in ABCD (Amsterdam Born Children and Their Development) study (n=2052). All analyses were adjusted for child's age, sex, height, and body mass index (BMI), and maternal education and subsequently performed in the combined sample. No associations were found between maternal smoking during pregnancy and childhood blood pressure. In the total sample, maternal prepregnancy BMI was positively associated with systolic blood pressure (SBP) (β [95% CI], 0.09 [0.02-0.16] mm Hg) and diastolic blood pressure (β [95% CI], 0.11 [0.04-0.17] mm Hg). Children of women with hypertension had higher SBP (β [95% CI], 0.98 [0.17-1.79] mm Hg). Birth weight standardized for gestational age was inversely associated with SBP (β [95% CI], -6.93 [-9.25 to -4.61] mm Hg) and diastolic blood pressure (β [95% CI], -3.65 [-5.70 to -1.61] mm Hg). Longer gestational age was associated with lower SBP (β [95% CI] per week, -0.25 [-0.42 to -0.08] mm Hg). Breastfeeding for 1 to 3 months was associated with lower SBP (β [95% CI], -0.96 [-1.82 to -0.09] mm Hg) compared with no or <1 month of breastfeeding. Early BMI gain from the age of 2 to 6 years was positively associated with SBP (β [95% CI], 0.41 [0.08-0.74] mm Hg) and diastolic blood pressure (β [95% CI], 0.37 [0.07-0.66] mm Hg), but no effect modification by birth weight was found. Conclusions Higher maternal prepregnancy BMI, maternal hypertension, a relatively lower birth weight for gestational age, shorter gestational age, limited duration of breastfeeding, and more rapid early BMI gain contribute to higher childhood blood pressure at the age of 6 years

Ambulatory heart rate is underestimated when measured by an ambulatory blood pressure device

Objective: To test the validity of ambulatory heart rate (HR) assessment with a cuff ambulatory blood pressure (ABP) monitor. Design: Cross-instrument comparison of HR measured intermittently by a cuff ABP monitor (SpaceLabs, Redmond, Washington, USA), with HR derived from continuous electrocardiogram (ECG) recordings (1) in a controlled laboratory experiment and (2) during long-term recording in a true naturalistic setting. Participants: Six normotensive subjects participated in the laboratory study. A total of 109 male white-collar workers underwent ambulatory monitoring, of which 30 were mildly hypertensive. Methods: Four different laboratory conditions (postures: lying, sitting, standing, walking), repeated twice, were used to assess the short-term effects of cuff inflation on the HR. To test the actual ambulatory validity, participants simultaneously wore a continuous HR recorder and the ABP monitor from early morning to late evening on 2 workdays and one non-workday. Diary and vertical accelerometery information was used to obtain periods of fixed posture and (physical) activity across which HR from both devices was compared. Results: Laboratory results showed that the ABP device reliably detected HR during blood pressure measurement, but that this HR was systematically lower than the HR directly before and after the blood pressure measurement. The ambulatory study confirmed this systematic underestimation of the ongoing HR, but additionally showed that its amount increased when subjects went from sitting to standing to light physical activity (2.9; 4.3 and 9.1 bpm (beats/min), respectively). In spite of this activity-dependent underestimation of HR, the correlation of continuous ECG and intermittent ABP-derived HR was high (median r = 0.81). Also, underestimation was not different for normotensives and mild hypertensives. Conclusions: A direct effect of cuff inflation leads to the underestimation of ongoing HR during cuff-based ABP measurement. Additional underestimation of HR occurs during periods with physical activity, probably due to behavioural freezing during blood pressure measurements. HR underestimation was not affected by hypertensive state. When its limitations are taken into account, ABP-derived ambulatory HR can be considered a reliable and valid measure. © 2001 Lippincott Williams & Wilkins

Influence of Dietary Approaches to Stop Hypertension-Type Diet, Known Genetic Variants and Their Interplay on Blood Pressure in Early Childhood ABCD Study

There is limited evidence on association between adherence to the Dietary Approaches to Stop Hypertension (DASH diet) and a lower blood pressure (BP) in children. In a population-based cohort study, among 1068 Dutch children aged 5 to 7, we evaluated the association between a DASH-type diet, 29 known genetic variants incorporated in a genetic risk score, and their interaction on BP. We calculated DASH score based on the food intake data measured through a validated 71-item food frequency questionnaire. In our sample, DASH score ranged from 9 (low adherence to the DASH diet) to 33 (median=21), and genetic score ranged from 18 (low genetic risk on high BP) to 41 (median=29). After adjustment for covariates, each 10 unit increase in DASH score was associated with a lower systolic BP of 0.7 mm Hg (P=0.033). DASH score was negatively associated with hypertension (odds ratio=0.96 [0.92-0.99], P=0.044). Similarly, each SD increment in genetic score was associated with 0.5 mm Hg higher diastolic BP (P=0.002). We found a positive interaction between low DASH score and high genetic score on diastolic BP adjusted for BP risk factors (β=1.52, Pinteraction=0.019 in additive scale and β=0.03, Pinteraction=0.021 in multiplicative scale). Our findings show that adherence to the DASH-type diet, as well as a low (adult-derived) genetic risk profile for BP, is associated with lower BP in children and that the genetic basis of BP phenotypes at least partly overlaps between adults and children. In addition, we found evidence of a gene-diet interaction on BP in children

Determinants of Cortisol During Pregnancy − the ABCD Cohort

BACKGROUND: Psychosocial stress during pregnancy has been proposed as a major contributor of glucocorticoid-mediated programming of the fetal hypothalamic-pituitary adrenal (HPA) axis, with later adverse health consequences. However, evidence linking maternal stress to maternal cortisol values during pregnancy is inconclusive. A possible explanation for this is that other maternal factors overshadow any potential effects of stress on cortisol levels. We studied a large cohort of pregnant women with extensive data on pregnancy characteristics to determine the respective contributions of biological, environmental and psychosocial stress factors to cortisol levels in pregnancy. METHODS: We used data from 3039 women from the Amsterdam Born Children and their Development-study cohort. Serum cortisol was measured in blood, collected at the first prenatal visit, at different gestational ages (median=91days, range=40-256days), and at various time points during the day (median=11:45h, range=08:00-18:30h). We assessed associations between maternal serum cortisol in pregnancy and biological factors, lifestyle factors and stress factors, including depression, anxiety, pregnancy-related anxiety, work stress, parenting stress and fatigue. RESULTS: In multivariable analysis, variables that were associated with higher cortisol levels in pregnancy were lower maternal age [1.5nmol/l, 95%CI (0.6-2.4)], being nulliparous [21.5 nmol/l (15.9-27.1)], lower pre-pregnancy body mass index (BMI) [1.3nmol/l (0.3-2.4)], higher C-reactive protein (CRP) [1.0nmol/l (0.4-1.5)], carrying a female fetus [9.2nmol/l (1.8-16.5)], non-smoking [14.2nmol/l (0.6-27.7)], sufficient sleep [8.5nmol/l (0.9-16.1)], and being unemployed [12.7nmol/l (2.2-23.2)]. None of the psychosocial stressors was significantly associated with serum cortisol levels in pregnancy. A total of 32% of all variance in cortisol was explained by gestational age, maternal age, time of day, parity, pre-pregnancy BMI, CRP, fetal sex, smoking behavior, self-reported sleep sufficiency, and employment. CONCLUSIONS: Our data suggest that maternal cortisol during pregnancy is mainly affected by biological and lifestyle factors, but not by psychosocial factors. We suggest that psychosocial stress in pregnancy might program the fetus through other mechanisms than through altering maternal cortisol levels

The Association between Prenatal Psychosocial Stress and Blood Pressure in the Child at Age 5-7 Years

OBJECTIVE: Prenatal maternal stress could have permanent effects on the offspring's tissue structure and function, which may predispose to cardiovascular diseases. We investigated whether maternal psychosocial stress is a prenatal factor affecting the blood pressure (BP) of offspring. STUDY DESIGN: In the Amsterdam Born Children and their Development (ABCD) study, around gestational week 16, depressive symptoms, state-anxiety, pregnancy-related anxiety, parenting daily hassles and job strain were recorded by questionnaire. A cumulative stress score was also calculated (based on 80(th) percentiles). Systolic and diastolic BP and mean arterial pressure (MAP) were measured in the offspring at age 5-7 years. Inclusion criteria were: no use of antihypertensive medication during pregnancy; singleton birth; no reported cardiovascular problems in the child (N = 2968 included). RESULTS: After adjustment for confounders, the single stress scales were not associated with systolic and diastolic BP, MAP and hypertension (p>0.05). The presence of 3-4 psychosocial stressors prenatally (4%) was associated with 1.5 mmHg higher systolic and diastolic BP (p = 0.046; p = 0.04) and 1.5 mmHg higher MAP in the offspring (p = 0.02) compared to no stressors (46%). The presence of 3-4 stressors did not significantly increase the risk for hypertension (OR 1.8; 95% CI 0.93.4). Associations did not differ between sexes. Bonferroni correction for multiple testing rendered all associations non-significant. CONCLUSIONS: The presence of multiple psychosocial stressors during pregnancy was associated with higher systolic and diastolic BP and MAP in the child at age 5-7. Further investigation of maternal prenatal stress may be valuable for later life cardiovascular health

Ethnic Differences in Cardiometabolic Risk Profile at Age 5-6 Years: The ABCD Study

Background: To examine ethnic differences in cardiometabolic risk profile in early age, and explore whether such differences can be explained by differences in body mass index (BMI) or waist circumference (WC). Method: Anthropometric measurements, blood pressure and (in a subsample) fasting blood were collected during a health check of 2,509 children aged 5-6 years. Four ethnic groups were distinguished: Dutch (n = 2,008; blood n = 1,300), African descent (n = 199; blood n = 105), Turkish (n = 108; blood n = 57) and Moroccan (n = 194; blood n = 94). Ethnic differences in diastolic and systolic blood pressure (DBP/SBP), fasting glucose, low-density lipoprotein (LDL), high-density lipoprotein (HDL) and triglyceride levels were determined and the explanatory role of BMI and WC was examined with regression analysis. Results: After adjustment for confounders, African descent children showed higher DBP (beta 2.22 mmHg; 95% CI: 1.09-3.36) and HDL levels (beta:0.09 mmol/l; 95% CI: 0.03-0.16) compared to Dutch children (reference group). Turkish children showed higher SBP (beta:1.89 mmHg; 95% CI: 0.25-3.54), DBP (beta:2.62 mmHg; 95% CI: 1.11-4.13), glucose (beta:0.12 mmol/L; 95% CI: 0.00-0.25) and triglyceride levels (beta:0.13 mmol/L; 95% CI: 0.02-0.25). Higher BMI values were found in all non-Dutch groups (differences ranged from 0.53-1.03 kg/m(2)) and higher WC in Turkish (beta:1.68 cm; 95% CI: 0.99-2.38) and Moroccan (beta:1.65 cm; 95% CI:1.11-2.19) children. BMI and WC partly explained the higher SBP/DBP and triglyceride levels in Turkish children. Conclusion: Ethnic differences in cardiometabolic profile exist early in life and are partly explained by differences in BMI and WC. African children showed favourable HDL levels and Turkish children the most unfavourable overall profile, whereas their Moroccan peers have less increased cardiometabolic risk in spite of their high BMI and W

Spatial and temporal variability of personal environmental exposure to radio frequency electromagnetic fields in children in Europe

Exposure to radiofrequency electromagnetic fields (RF-EMF) has rapidly increased and little is known about exposure levels in children. This study describes personal RF-EMF environmental exposure levels from handheld devices and fixed site transmitters in European children, the determinants of this, and the day-to-day and year-to-year repeatability of these exposure levels.; Personal environmental RF-EMF exposure (μW/m; 2; , power flux density) was measured in 529 children (ages 8-18 years) in Denmark, the Netherlands, Slovenia, Switzerland, and Spain using personal portable exposure meters for a period of up to three days between 2014 and 2016, and repeated in a subsample of 28 children one year later. The meters captured 16 frequency bands every 4 s and incorporated a GPS. Activity diaries and questionnaires were used to collect children's location, use of handheld devices, and presence of indoor RF-EMF sources. Six general frequency bands were defined: total, digital enhanced cordless telecommunications (DECT), television and radio antennas (broadcast), mobile phones (uplink), mobile phone base stations (downlink), and Wireless Fidelity (WiFi). We used adjusted mixed effects models with region random effects to estimate associations of handheld device use habits and indoor RF-EMF sources with personal RF-EMF exposure. Day-to-day and year-to-year repeatability of personal RF-EMF exposure were calculated through intraclass correlations (ICC).; Median total personal RF-EMF exposure was 75.5 μW/m; 2; . Downlink was the largest contributor to total exposure (median: 27.2 μW/m; 2; ) followed by broadcast (9.9 μW/m; 2; ). Exposure from uplink (4.7 μW/m; 2; ) was lower. WiFi and DECT contributed very little to exposure levels. Exposure was higher during day (94.2 μW/m; 2; ) than night (23.0 μW/m; 2; ), and slightly higher during weekends than weekdays, although varying across regions. Median exposures were highest while children were outside (157.0 μW/m; 2; ) or traveling (171.3 μW/m; 2; ), and much lower at home (33.0 μW/m; 2; ) or in school (35.1 μW/m; 2; ). Children living in urban environments had higher exposure than children in rural environments. Older children and users of mobile phones had higher uplink exposure but not total exposure, compared to younger children and those that did not use mobile phones. Day-to-day repeatability was moderate to high for most of the general frequency bands (ICCs between 0.43 and 0.85), as well as for total, broadcast, and downlink for the year-to-year repeatability (ICCs between 0.49 and 0.80) in a small subsample.; The largest contributors to total personal environmental RF-EMF exposure were downlink and broadcast, and these exposures showed high repeatability. Urbanicity was the most important determinant of total exposure and mobile phone use was the most important determinant of uplink exposure. It is important to continue evaluating RF-EMF exposure in children as device use habits, exposure levels, and main contributing sources may change

Associations between maternal physical activity in early and late pregnancy and offspring birth size: remote federated individual level meta-analysis from eight cohort studies.

OBJECTIVE: Evidence on the impact of leisure time physical activity (LTPA) in pregnancy on birth size is inconsistent. We aimed to examine the association between LTPA during early and late pregnancy and newborn anthropometric outcomes. DESIGN: Individual level meta-analysis, which reduces heterogeneity across studies. SETTING: A consortium of eight population-based studies (seven European and one US) comprising 72,694 participants. METHODS: Generalised linear models with consistent inclusion of confounders (gestational age, sex, parity, maternal age, education, ethnicity, BMI, smoking and alcohol intake) were used to test associations between self-reported LTPA at either early (8-18 weeks gestation) or late pregnancy (30+ weeks) and the outcomes. Results were pooled using random effects meta-analyses. MAIN OUTCOME MEASURES: Birth weight, Large-for-gestational age (LGA), macrosomia, small-for-gestational age (SGA), %body fat and ponderal index at birth. RESULTS: Late, but not early, gestation maternal moderate-to-vigorous physical activity (MVPA), vigorous activity and LTPA energy expenditure were modestly inversely associated with BW, LGA, macrosomia and ponderal index, without heterogeneity (all: I-square=0%). For each extra hour/week of MVPA, RR for LGA and macrosomia were 0.97 (95% CI: 0.96, 0.98) and 0.96 (95%CI: 0.94, 0.98) respectively. Associations were only modestly reduced after additional adjustments for maternal BMI and gestational diabetes. No measure of LTPA was associated with risk for SGA. CONCLUSIONS: Physical activity in late, but not early, pregnancy is consistently associated with modestly lower risk of LGA and macrosomia, but not SGA. This article is protected by copyright. All rights reserved.Includes MRC, Wellcome Trust and NIHR