Childhood obesity and blood pressure: back to the future?

Exome sequencing implicates ancestry-related Mendelian variation at SYNE1 in childhood-onset essential hypertension

Childhood-onset essential hypertension (COEH) is an uncommon form of hypertension that manifests in childhood or adolescence and, in the United States, disproportionately affects children of African ancestry. The etiology of COEH is unknown, but its childhood onset, low prevalence, high heritability, and skewed ancestral demography suggest the potential to identify rare genetic variation segregating in a Mendelian manner among affected individuals and thereby implicate genes important to disease pathogenesis. However, no COEH genes have been reported to date. Here, we identify recessive segregation of rare and putatively damaging missense variation in the spectrin domain of spectrin repeat containing nuclear envelope protein 1 (SYNE1), a cardiovascular candidate gene, in 3 of 16 families with early-onset COEH without an antecedent family history. By leveraging exome sequence data from an additional 48 COEH families, 1,700 in-house trios, and publicly available data sets, we demonstrate that compound heterozygous SYNE1 variation in these COEH individuals occurred more often than expected by chance and that this class of biallelic rare variation was significantly enriched among individuals of African genetic ancestry. Using in vitro shRNA knockdown of SYNE1, we show that reduced SYNE1 expression resulted in a substantial decrease in the elasticity of smooth muscle vascular cells that could be rescued by pharmacological inhibition of the downstream RhoA/Rho-associated protein kinase pathway. These results provide insights into the molecular genetics and underlying pathophysiology of COEH and suggest a role for precision therapeutics in the future.

Childhood Obesity: Insight into Kidney Involvement

This review examines the impact of childhood obesity on the kidney from an epidemiological, pathogenetic, clinical, and pathological perspective, with the aim of providing pediatricians and nephrologists with the most current data on this topic. The prevalence of childhood obesity and chronic kidney disease (CKD) is steadily increasing worldwide, reaching epidemic proportions. While the impact of obesity in children with CKD is less pronounced than in adults, recent studies suggest a similar trend in the child population. This is likely due to the significant association between obesity and the two leading causes of end-stage renal disease (ESRD): diabetes mellitus (DM) and hypertension. Obesity is a complex, systemic disease that reflects interactions between environmental and genetic factors. A key mechanism of kidney damage is related to metabolic syndrome and insulin resistance. Therefore, we can speculate about an adipose tissue-kidney axis in which neurohormonal and immunological mechanisms exacerbate complications resulting from obesity. Adipose tissue, now recognized as an endocrine organ, secretes cytokines called adipokines that may induce adaptive or maladaptive responses in renal cells, leading to kidney fibrosis. The impact of obesity on kidney transplant-related outcomes for both donors and recipients is also significant, making stringent preventive measures critical in the pre- and post-transplant phases. The challenge lies in identifying renal involvement as early as possible, as it is often completely asymptomatic and not detectable through common markers of kidney function. Ongoing research into innovative technologies, such as proteomics and metabolomics, aims to identify new biomarkers and is constantly evolving. Many aspects of pediatric disease progression in the population of children with obesity still require clarification. However, the latest scientific evidence in the field of nephrology offers glimpses into various new perspectives, such as genetic factors, comorbidities, and novel biomarkers. Investigating these aspects early could potentially improve the prognosis of these young patients through new diagnostic and therapeutic strategies. Hence, the aim of this review is to provide a comprehensive exploration of the pathogenetic mechanisms and prevalent pathological patterns of kidney damage observed in children with obesity.

The relationship between parental locus of control and adolescent obesity: a longitudinal pre-birth cohort

OBJECTIVES

To investigate whether parental external locus of control (ELOC) measured in pregnancy is related to obesity in their adolescent offspring and whether the child's own ELOC measured at age 8 contributes. To determine whether associations are due to types of behaviour used by externally oriented participants.

SUBJECTS/METHODS

Longitudinal pre-birth cohort study (Avon Longitudinal Study of Parents & Children (ALSPAC)) set in south-west England. Families whose adolescent offspring had their fat mass measured using DXA scans at any of ages 9, 11, 13, 15 or 17 (range, n = 7329 at 9 to n = 4850 at 17). The primary outcome measures were mean fat mass, and obesity measured as ≥85th centile of fat mass at each age.

RESULTS

We found that parent and child externality was associated with greater fat mass [e.g., mean difference at age 15 associated with maternal ELOC was 1.70 kg (+1.17, +2.24), paternal ELOC 1.49 kg (+0.89, +2.09) and child's ELOC 1.50 kg (+0.93, +2.06) (P < 0.0001)]. Further analyses showed that factors associated with parent behaviour such as smoking in pregnancy, failure to breast feed, and early introduction of solids accounted for a third of the excess fat mass associated with maternal externality, whereas aspects of diet and energetic activity in later childhood were not. Further analyses demonstrated that the child's own ELOC only became independently important for adolescent obesity from age 13, whereas the mothers' and to a lesser extent the fathers' ELOC were associated at each age.

CONCLUSIONS

There is increased interest in determining factors that may be involved in the aetiology and maintenance of excessive weight in adolescents. We demonstrate that parental locus of control is a promising candidate. We suggest interventions to change parents' locus of control towards internality in pregnancy might have long-term preventative benefits on the likelihood of obesity in the offspring.

Heterogeneity in Blood Pressure Transitions Over the Life Course: Age-Specific Emergence of Racial/Ethnic and Sex Disparities in the United States

Importance

Many studies have assessed racial/ethnic and sex disparities in the prevalence of elevated blood pressure (BP) from childhood to adulthood, yet few have examined differences in age-specific transitions between categories of BP over the life course in contemporary, multiracial/multiethnic populations.

Objective

To estimate age, racial/ethnic, and sex-specific annual net transition probabilities between categories of BP using Markov modeling of cross-sectional data from the National Health and Nutrition Examination Survey.

Design, Setting, and Participants

National probability sample (National Health and Nutrition Examination Survey in 2007-2008, 2009-2010, and 2011-2012) of 17 747 African American, white American, and Mexican American participants aged 8 to 80 years. The data were analyzed from September 2014 to November 2015.

Main Outcomes and Measures

Age-specific American Heart Association-defined BP categories.

Results

Three National Health and Nutrition Examination Survey cross-sectional samples were used to characterize the ages at which self-reported African American (n = 4973), white American (n = 8886), and Mexican American (n = 3888) populations transitioned between ideal BP, prehypertension, and hypertension across the life course. At age 8 years, disparities in the prevalence of ideal BP were observed, with the prevalence being lower among boys (86.6%-88.8%) compared with girls (93.0%-96.3%). From ages 8 to 30 years, annual net transition probabilities from ideal to prehypertension among male individuals were more than 2 times the net transition probabilities of their female counterparts. The largest net transition probabilities for ages 8 to 30 years occurred in African American young men, among whom a net 2.9% (95% CI, 2.3%-3.4%) of those with ideal BP transitioned to prehypertension 1 year later. Mexican American young women aged 8 to 30 years experienced the lowest ideal to prehypertension net transition probabilities (0.6%; 95% CI, 0.3%-0.8%). After age 40 years, ideal to prehypertension net transition probabilities stabilized or decreased (range, 3.0%-4.5%) for men, whereas net transition probabilities for women increased rapidly (range, 2.6%-13.0%). Mexican American women exhibited the largest ideal to prehypertension net transition probabilities after age 60 years. The largest prehypertension to hypertension net transition probabilities occurred at young ages in boys of white race/ethnicity and African Americans, approximately age 8 years and age 25 years, respectively, while net transition probabilities for white women and Mexican Americans increased over the life course.

Conclusions and Relevance

Heterogeneity in net transition probabilities from ideal BP emerge during childhood, with associated rapid declines in ideal BP observed in boys and African Americans, thus introducing disparities. Primordial prevention beginning in childhood and into early adulthood is necessary to preempt the development of prehypertension and hypertension, as well as associated racial/ethnic and sex disparities.

The effects of school-based lifestyle interventions on body mass index and blood pressure: a multivariate multilevel meta-analysis of randomized controlled trials

Primary prevention of childhood obesity and related hypertension is warrant given that both risk factors are intertwined and track into adulthood. This systematic review and meta-analysis assess the impact of school-based lifestyle interventions on children's body mass index (BMI) and blood pressure. We searched databases and prior reviews. Eligibility criteria were the following: randomized controlled trial design, evaluation of a school-based intervention, targeting children aged 4-12 years, reporting on BMI and/or related cardiovascular risk factors, reporting data on at least one follow-up moment. The effects on BMI, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were evaluated by means of univariate and multivariate three-level random effects models. A total of 85 RCTs (91 papers) were included in the meta-analyses. In univariate models, the pooled effects were -0.072 (95%CI: -0.106; -0.038) for BMI, -0.183 (95%CI: -0.288; -0.078) for SBP and -0.071 (95%CI: -0.185; 0.044) for DBP. In multivariate analyses, the pooled effects of interventions were -0.054 (95%CI: -0.131; 0.022) for BMI, -0.182 (95%CI: -0.266; -0.098) for SBP and -0.144 (95%CI: -0.230; -0.057) for DBP. Parental involvement accentuated the beneficial effects of interventions. School-based lifestyle prevention interventions result in beneficial changes in children's BMI and blood pressure, and the effects on the latter may be stronger than and accrue independently from those in the former.

Sex differences in the association between body mass index and hypertension - a cross-sectional study in 717 812 adolescents

In order to examine sex-specific differences in the association of body mass index (BMI) and hypertension, we conducted a retrospective, cross-sectional study of 717 812 (402 914 men and 314 898 women) Israeli Jewish adolescents aged 16.0-19.99 years medically screened for military service. A diagnosis of hypertension was established per history or if a mean of 10 separate blood pressure measurements exceeded 140/90, following an initial measurement higher than 140/90. Weight and height were measured. Prevalence of hypertension was 0.42% in men and 0.05% in women. In men, BMI was significantly associated with hypertension from the third decile (odds ratio [OR] 1.67, 1.06-2.65) up to the 10th decile (OR 30.17, 20.83-43.69). In women, we observed a significantly increased risk for hypertension in the ninth decile (OR 3.82, 1.42-10.22) and in the 10th decile (OR 18.92, 7.7-46.51), with no visible trend in lower deciles. BMI effects on hypertension prevalence are different in male and female adolescents.

Factors associated with knowledge of hypertension among adolescents: implications for preventive education programs in primary care

Background

Hypertension (HT) amongst adolescents remains a vital issue of both a medical and social nature. There is a lack of data regarding the factors influencing the awareness of the disease among the youth. The aim of this study was to evaluate the knowledge about HT among adolescents and its level corresponding to the selected demographic, environmental and medical factors.

Methods

The study was carried out among 250 adolescents of secondary schools. The authors’ questionnaire poll and the psychological tests Personal Values List (PVL) and Personal Competence Scale (PCS) were performed.

Results

Only 13.2% of the youth surveyed displayed the “medium” level (defined below) of HT knowledge. Most of them present satisfactory knowledge about the causes of HT. The children from urban areas generally displayed better knowledge about HT than their peers from rural regions. Only the children who had had their blood pressure previously examined displayed good knowledge about HT. The most frequently indicated source of this knowledge was school; however, its level still remains low. There was no significant association between the level of global knowledge about HT and the feeling of one’s own competences and considering the category “good health” an important personal value.

Conclusions

Knowledge about HT among adolescents remains unsatisfactory and random, which indicates the necessity for routine education in this field, especially as it applies to HT symptoms. It seems that the consideration of such elements as blood pressure measurement and family history of HT in education programs can improve their efficiency.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-1773-7) contains supplementary material, which is available to authorized users.

Is obesity a risk factor for chronic kidney disease in children?

There is a rapid increase worldwide in the prevalence of obesity in adults and children. Obesity is not only a comorbidity for chronic kidney disease (CKD) but may also be a risk factor for CKD. Epidemiological correlations and pathophysiological changes have been observed associating obesity with CKD. Low birth weight may be associated with both obesity and low nephron mass, leading to CKD later in life. Elevated levels of adipokines, such as leptin and adiponectin, in obesity may be factors in CKD pathogenesis and progression. Furthermore, various other factors, such as hypertension, increased cardiovascular morbidity, insulin resistance, dyslipidemia, and lipotoxicity, may play significant roles in the pathogenesis of CKD in obesity. Reduction in obesity, which is a potentially modifiable risk factor, might help decrease the burden of CKD in the population. Apart from individualized options, community-based interventions have the potential to create a strong impact in this condition.

Increasing body mass index, blood pressure, and Acanthosis Nigricans abnormalities in school-age children

This retrospective quantitative study examined the relationships among gender, Acanthosis Nigricans (AN), body mass index (BMI), and blood pressure (BP) in children attending school Grades 1-9 in Southwest Texas. Of the 34,897 health screening records obtained for the secondary analysis, 32,788 were included for the study. A logistic regression analysis was carried out with AN as the dependent variable, with year, gender, BMI, and BP as independent variables. The results indicate that the rate of children in each grade with three positive markers increased 2% during a 3-year period between 2008 and 2010. In the 5-year period between 2005 and 2010, a clear trend of significantly higher numbers of children with both AN and BMI markers was apparent. Gender played a significant role as females were more likely to have the AN marker than males. Further study is indicated based on the increasing trend of school-age children in Texas with positive markers for AN, increased BMI and BP.