Associations of social and economic and pregnancy exposures with blood pressure in UK White British and Pakistani children age 4/5

Ethnic differences in kidney function in childhood: the Born in Bradford Cohort Renal Study

Background: Endstage kidney failure rates are higher in South Asians than in White Europeans. Low birth weight is associated with adult chronic kidney disease and is more common in South Asians. Foetal kidney size was smaller in South Asians in the Born in Bradford (BiB) birth cohort. As part of BiB follow up, we aimed to investigate if there were ethnic differences in kidney function and blood pressure in early childhood and whether this was different by foetal kidney size. Methods: Serum creatinine, cystatin C, urea, and urinary albumin to creatinine ratio (ACR), protein to creatinine ratio (PCR) and retinol binding protein (RBP) were analysed in blood and urine samples from those who participated in the BiB follow-up at 7-11 years. Ethnicity was categorised by parental self-report as White European and South Asian. Estimated glomerular filtration rate (eGFR) was calculated using Schwartz, and cystatin C Zappitelli and Filler equations. Linear regression was used to examine the association between ethnicity and eGFR, PCR and blood pressure. Results: 1591 children provided blood (n=1403) or urine (n=625) samples. Mean eGFR was 92 ml/min/1.73m 2 (standard deviation (SD) 9) using Schwartz (n=1156) and 94 (SD 11) using Zappitelli (n=1257). CKD prevalence was rare (1 with eGFR <60 ml/min/1.73m 2, 14 (2.4%) had raised ACR (>2.5 mg/mmol in boys/3.5 mg/mmol in girls). Diastolic blood pressure was higher in South Asian children (difference 2.04 mmHg, 95% CI 0.99 to 3.10) but was not significant in adjusted analysis. There was no evidence of association in adjusted models between ethnicity and any eGFR or urinary measure at this age. Conclusions: There was no evidence of significant ethnic differences in kidney function at pre-pubertal age despite differences in kidney volume at birth. Longitudinal follow-up is required to track ethnic patterns in kidney function and blood pressure as children develop through puberty.

Molecular Genotyping of Chlamydia trachomatis in Iraqi Married Pregnant and Non-Pregnant Women

It has been approved that the infection caused by Chlamydia trachomatis (C. trachomatis) is one of the major causes of infertility and adverse birth outcomes in populations. The C. trachomatis epidemiology among childbearing-age women in Iraq has not been recognized yet. This study aimed to detect the prevalence of C. trachomatis infection among pregnant and non-pregnant women using the polymerase chain reaction (PCR) assay and phylogenetic analysis of local isolates. In total, 200 endocervical swabs were collected from adult married pregnant (n=100) and non-pregnant women (n=100) from June to July 2021. Targeting the omp1 gene, 9% of the total samples were positive for C. trachomatis, and significant increases were reported among non-pregnant compared to pregnant women. The PCR products of five positive local isolates were selected randomly, sequenced, and documented in the National Centre for Biotechnology Information (NCBI) with the accession numbers OK094104.1, OK094105.1, OK094106.1, OK094107.1, and OK094108.1. Analysis of the homology sequence of the local and NCBI-BLAST isolates revealed a significant association with the Russian (MF288585.1) isolate. Statistical analysis of reproductive data revealed a higher prevalence, odds ratio (OD), and risk in asymptomatic, compared to symptomatic cases. Although no significant variation was detected in prevalence rate among single and multiple symptomatic women, increases were observed in OD values and risk of multiple symptomatic women. Reportedly, chronic pelvic pain was more prevalent than pelvic inflammatory diseases, ectopic pregnancy, and infertility in single symptomatic women. Regarding the demographic characteristics (i.e., age, the place of residence, and occupation), prevalence and risk of infection were higher in women who were <30 years, lived in urban areas, and had a job, compared to women who were ≥30 years, lived in suburban and rural areas, and had a free job. In conclusion, the course of chlamydial infections is usually unpredictable, diverse, and asymptomatic and has remained almost unrecognized. Therefore, PCR-based methods can apply successfully to detect C. trachomatis in both pregnant and non-pregnant women.

Maternal pregnancy weight or gestational weight gain and offspring's blood pressure: A systematic review

AIMS

An increasing number of studies suggest that maternal weight parameters in pregnancy are associated with offspring's blood pressure (BP). The aim of this systematic review - following the updated Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) Statement - was to assess and judge the evidence for an association between maternal pregnancy weight/body mass index (BMI) or gestational weight gain (GWG) with offspring's BP in later life.

DATA SYNTHESIS

MEDLINE, EMBASE, Cochrane Library, CINAHL and Web of Science were searched without limits. Risk of bias was assessed using the "US National Heart, Lung and Blood Institute"-tool, and an evidence grade was allocated following the "World Cancer Research Fund" criteria. Of 7,124 publications retrieved, 16 studies (all cohort studies) were included in the systematic review. Overall data from 52,606 participants (0 years [newborns] to 32 years) were enclosed. Association between maternal pregnancy BMI and offspring's BP were analyzed in 2 (both "good-quality" rated) studies, without consistent results. GWG and offspring's BP was analyzed in 14 studies (2 "good-quality", 9 "fair-quality", 3 "poor-quality" rated). Of these, 3 "fair-quality" studies described significant positive results for systolic BP and significant results, but partly with varying directions of effect estimates for diastolic BP. Mean arterial pressure (MAP) was analyzed in 1 "poor-quality" congress paper. Overall, based on the small number of "good-quality"-rated studies and the inconsistency of effect direction, no firm conclusion can be drawn.

CONCLUSION

Evidence for an association of maternal pregnancy weight determinants with offspring's BP was overall graded as "limited - no conclusion".

Associations of maternal gestational hypertension with high blood pressure and overweight/obesity in their adolescent offspring: a retrospective cohort study

Maternal hypertensive disorders during pregnancy may have an impact on fetal development and the health of the offspring in later life. The aim of the study was to evaluate the associations of maternal gestational hypertension (GH) with high blood pressure (HBP) (prehypertension/hypertension) and overweight/obesity in their adolescent offspring at the age of 12 to 15 years. We analyzed data of 4819 participants born in Kaunas city during 1995-1998 who were included in the study "Prevalence and Risk Factors of HBP in 12-15-Year-Old Lithuanian Children and Adolescents". The diagnosis of maternal gestational hypertension was obtained from medical records. Associations of maternal GH with their offspring's HBP and overweight/obesity in adolescence were assessed by multivariate logistic regression analysis. Among 4819 adolescents of 12-15 years of age, 25.7% had HBP, 12% had overweight, and 2.5% had obesity. Of 4819 mothers, 92.3% were normotensive during pregnancy, and 7.7% had GH. In the multivariate analysis after adjustment for age, sex, birth weight, adolescent BMI, and maternal pre/early pregnancy BMI, adolescent offspring born to mothers with GH had higher odds of prehypertension, hypertension, and prehypertension/hypertension (aOR 1.58; 95% CI 1.13-2.22; aOR 1.87; 95% CI 1.41-2.47; and aOR 1.76, 95% CI 1.39-2.24; respectively), compared to the offspring of normotensive mothers. After adjustment for age, sex, birth weight, and maternal pre/early pregnancy BMI, a significant association was found between maternal GH and the offspring's overweight/obesity in adolescence (aOR 1.41; 95% CI 1.04-1.91). The findings of this study suggest that maternal GH is associated with an increased odds of HBP (prehypertension and hypertension, both separately and combined) and overweight/obesity in their offspring during adolescence.

Expression and role of miR-338-3p in peripheral blood and placenta of patients with pregnancy-induced hypertension

The present study aimed to investigate the role of miR-338-3p in pregnancy-induced hypertension (PIH), and its effects on human trophoblast cells in vitro. Quantitative real-time PCR was used to detect miR-338-3p expression. Human trophoblast HTR8/SVneo cells were transfected with miR-338-3p mimics. Effects of miR-338-3p on cell proliferation, invasion and metastasis, and anoikis resistance were detected by CCK-8 assay, Transwell chamber assay, flow cytometry and western blot analysis, respectively. Bioinformatics analysis was performed to predict the target of miR-338-3p, and the results were confirmed by dual luciferase reporter assay. The expression level of miR-338-3p was significantly upregulated in the peripheral blood and placenta of PIH patients. CCK-8 assay showed that miR-338-3p mimics inhibited the proliferation of HTR8/SVneo cells at indicated time points. Flow cytometry showed that miR-338-3p transfection significantly increased the Ki-67 expression in the HTR8/SVneo cells, indicating enhanced cell proliferation. Transwell chamber assay and western blot analysis showed that the invasion and metastatic abilities of the HTR8/SVneo cells were significantly decreased in the miR-338-3p transfection group, as well as expression levels of MMP-2 and MMP-9. Bioinformatics analysis and dual luciferase reporter assay indicated that AKT3 is a target gene of miR-338-3p. Our results suggest that miR-338-3p is significantly increased in the peripheral blood and placenta of PIH patients, which is correlated with the disease development. miR-338-3p inhibits proliferation, invasion and metastasis, and apoptosis resistance of human trophoblast cells by targeting AKT3.

Associations of cord leptin and cord insulin with adiposity and blood pressure in White British and Pakistani children aged 4/5 years

Background: Cord leptin and cord insulin concentrations may be important biomarkers of child adiposity and cardiovascular health, especially in populations with an increased long-term risk of type 2 diabetes and cardiovascular diseases. We aimed to determine whether cord leptin and insulin are associated with adiposity and early cardiovascular health at age 4/5, and whether any associations differ between White British and Pakistani children. Methods: Using bi-ethnic cohort data from 6060 mother-offspring pairs (2717 (44.8%) White British, 3343 (55.2%) Pakistani), we examined associations of cord leptin and insulin with adiposity (BMI, skinfold thickness) and systolic and diastolic blood pressure at age 4/5. Results: Cord leptin and insulin were higher in Pakistani compared to White British children (7.4 ng/ml versus 6.7 ng/ml and 4.1 mU/L versus 3.63 mU/L , respectively). Associations with adiposity measurements were similar in both groups and close to the null value. For example, each 10 ng/ml higher cord leptin was associated with a difference in mean childhood BMI of 0.10 kg/m 2 (95% CI 0.01, 0.19) in White British, 0.01 kg/m 2 (95% CI -0.08, 0.10) in Pakistani and 0.04 kg/m 2 (95% CI -0.02, 0.11) in both groups combined.  Associations with systolic and diastolic blood pressure were also close to the null and consistent in both groups. Conclusions: We found no evidence that cord leptin or insulin were likely to be valuable biomarkers for predicting later adiposity and blood pressure in White British or Pakistani children. For now, other factors such as family history and social-economic status may be more useful markers of risk.

Growing up in Bradford: protocol for the age 7-11 follow up of the Born in Bradford birth cohort

BACKGROUND

Born in Bradford (BiB) is a prospective multi-ethnic pregnancy and birth cohort study that was established to examine determinants of health and development during childhood and, subsequently, adult life in a deprived multi-ethnic population in the north of England. Between 2007 and 2010, the BiB cohort recruited 12,453 women who experienced 13,776 pregnancies and 13,858 births, along with 3353 of their partners. Forty five percent of the cohort are of Pakistani origin. Now that children are at primary school, the first full follow-up of the cohort is taking place. The aims of the follow-up are to investigate the determinants of children's pre-pubertal health and development, including through understanding parents' health and wellbeing, and to obtain data on exposures in childhood that might influence future health.

METHODS

We are employing a multi-method approach across three data collection arms (community-based family visits, school based physical assessment, and whole classroom cognitive, motor function and wellbeing measures) to follow-up over 9000 BiB children aged 7-11 years and their families between 2017 and 2021. We are collecting detailed parent and child questionnaires, cognitive and sensorimotor assessments, blood pressure, anthropometry and blood samples from parents and children. Dual x-ray absorptiometry body scans, accelerometry and urine samples are collected on subsamples. Informed consent is collected for continued routine data linkage to health, social care and education records. A range of engagement activities are being used to raise the profile of BiB and to disseminate findings.

DISCUSSION

Our multi-method approach to recruitment and assessment provides an efficient method of collecting rich data on all family members. Data collected will enhance BiB as a resource for the international research community to study the interplay between ethnicity, socioeconomic circumstances and biology in relation to cardiometabolic health, mental health, education, cognitive and sensorimotor development and wellbeing.