Socioeconomic Position Is Associated With Carotid Intima-Media Thickness in Mid-Childhood: The Longitudinal Study of Australian Children

Greenness modifies the association between ambient air pollution and cognitive function in Australian adolescents, but not in mid-life adults

Exposure to ambient air pollution has been associated with reduced cognitive function in childhood and later life, with too few mid-life studies to draw conclusions. In contrast, residential greenness has been associated with enhanced cognitive function throughout the lifecourse. Here we examine the extent to which (1) ambient air pollution and residential greenness predict later cognitive function in adolescence and mid-life, and (2) greenness modifies air pollution-cognitive function associations.

PARTICIPANTS

6220 adolescents (51% male) and 2623 mid-life adults (96% mothers) from the Longitudinal Study of Australian Children.

MEASURES

Exposures: Annual average particulate matter <2.5 μm (PM_2.5), nitrogen dioxide (NO₂) and greenness (Normalised Difference Vegetation Index) for residential addresses from validated land-use regression models over a 10-13-year period.

OUTCOMES

Cognitive function from CogState tests of attention, working memory and executive function, dichotomised into poorer (worst quartile) versus not poor.

ANALYSES

Adjusted mixed-effects generalised linear models with residential greenness assessed as an effect modifier (high vs. low divided at median). The annual mean for PM_2.5 and NO₂ across exposure windows was 6.3-6.8 μg/m³, and 5.5-7.1 ppb, respectively. For adolescents, an IQR increment of NO₂ was associated with 19-24% increased odds of having poorer executive function across all time windows, while associations weren't observed between air pollution and other outcomes. For adults, high NO₂ predicted poorer cognitive function across all outcomes, while high PM_2.5 predicted poorer attention only. There was little evidence of associations between greenness and cognitive function in adjusted models for both generations. Interactions were found between residential greenness, air pollutants and cognitive function in adolescents, but not adults. The magnitude of effects was similar across generations and exposure windows. Findings highlight the potential benefits of cognitive health associated with the regulation of air pollution and urban planning strategies for increasing green spaces and vegetation.

Diet quality trajectories and cardiovascular phenotypes/metabolic syndrome risk by 11-12 years

OBJECTIVE

To investigate associations between early-life diet trajectories and preclinical cardiovascular phenotypes and metabolic risk by age 12 years.

METHODS

Participants were 1861 children (51% male) from the Longitudinal Study of Australian Children. At five biennial waves from 2-3 to 10-11 years: Every 2 years from 2006 to 2014, diet quality scores were collected from brief 24-h parent/self-reported dietary recalls and then classified using group-based trajectory modeling as 'never healthy' (7%), 'becoming less healthy' (17%), 'moderately healthy' (21%), and 'always healthy' (56%). At 11-12 years: During children's physical health Child Health CheckPoint (2015-2016), we measured cardiovascular functional (resting heart rate, blood pressure, pulse wave velocity, carotid elasticity/distensibility) and structural (carotid intima-media thickness, retinal microvasculature) phenotypes, and metabolic risk score (composite of body mass index z-score, systolic blood pressure, high-density lipoproteins cholesterol, triglycerides, and glucose). Associations were estimated using linear regression models (n = 1100-1800) adjusted for age, sex, and socioeconomic position.

RESULTS

Compared to 'always healthy', the 'never healthy' trajectory had higher resting heart rate (2.6 bpm, 95% CI 0.4, 4.7) and metabolic risk score (0.23, 95% CI 0.01, 0.45), and lower arterial elasticity (-0.3% per 10 mmHg, 95% CI -0.6, -0.1) and distensibility (-1.2%, 95% CI -1.9, -0.5) (all effect sizes 0.3-0.4). Heart rate, distensibility, and diastolic blood pressure were progressively poorer for less healthy diet trajectories (linear trends p ≤ 0.02). Effects for systolic blood pressure, pulse wave velocity, and structural phenotypes were less evident.

CONCLUSIONS

Children following the least healthy diet trajectory had poorer functional cardiovascular phenotypes and metabolic syndrome risk, including higher resting heart rate, one of the strongest precursors of all-cause mortality. Structural phenotypes were not associated with diet trajectories, suggesting the window to prevent permanent changes remains open to at least late childhood.

American Heart Association ideal cardiovascular health score and subclinical atherosclerosis in 22-35-year-old adults conceived with and without assisted reproductive technologies

STUDY QUESTION

Is ART related with the association of American Heart Association (AHA) ideal cardiovascular health score and markers of subclinical atherosclerosis?

SUMMARY ANSWER

The associations between AHA score and markers of subclinical atherosclerosis in ART and non-ART groups were similar in magnitude.

WHAT IS KNOWN ALREADY

Long-term consequences of ART on cardiovascular health are unknown.

STUDY DESIGN, SIZE, DURATION

The study cohort for the cross-sectional analyses consisted of 172 ART-conceived and 78 non-ART conceived individuals of same age (range 22-35 years).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Cardiovascular risk factor status was evaluated with American Heart Association (AHA) ideal cardiovascular health score consisting of seven factors (body mass index, blood pressure, total cholesterol, glucose, diet and physical activity, non-smoking). Carotid artery intima-media thickness (cIMT), arterial pulse-wave velocity (PWV) and retinal microvascular parameters were evaluated as markers of early atherosclerosis. Group comparisons in continuous variables were performed with t-tests. For categorical variables, comparisons were performed with chi-square tests. The relationships between AHA score and the markers of atherosclerosis were examined with linear regression analyses adjusted for age and sex.

MAIN RESULTS AND THE ROLE OF CHANCE

There was no difference in AHA ideal health score between the ART and non-ART groups; mean (SD) scores were 4.1(1.4) versus 4.0(1.5), respectively, P = 0.65. No differences were observed between groups for any individual ideal health metric (P always >0.2). AHA score was not associated with cIMT or retinal measures in either group (P always >0.05). An inverse association was observed between AHA score and PWV in the ART group (beta (95% CI) -0.18(-0.26 to -0.10)). A numerically similar relationship was observed in the smaller non-ART group (-0.19(-0.39 to 0.01)).

LIMITATIONS, REASONS FOR CAUTION

Even though this cohort is among the largest ART studies with extensive cardiovascular data, the sample is still relatively small and the statistical power is limited. As the study population was still in early adulthood, we were not able to evaluate the associations with clinical cardiovascular events, but utilized non-invasive methods to assess early markers of subclinical atherosclerosis.

WIDER IMPLICATIONS OF THE FINDINGS

These findings suggest that ART-conceived individuals do not have increased vulnerability for cardiovascular risk factors.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by a National Health & Medical Research Council Project Grant (APP1099641), The Royal Children's Hospital Research Foundation, Monash IVF Research and Education Foundation, and Reproductive Biology Unit Sperm Fund, Melbourne IVF. The authors have no conflicts of interest relevant to this article to disclose.

Takeaway food, sugar-sweetened beverages and preclinical cardiometabolic phenotypes in children and adults

AIMS

To investigate relationships between takeaway food and sugar-sweetened beverage (SSB) consumption with cardiometabolic phenotypes during childhood and mid-adulthood.

METHOD

Design: Cross-sectional Child Health CheckPoint within the national population-representative Longitudinal Study of Australian Children. Participants: 1838 children (mean age 11.5 years; 49.1% female) and 1846 adults (mean age 43.7 years; 87.6% female). Exposures: Self-reported takeaway food and SSB consumption ('frequent': ≥ weekly). Outcomes: Functional (pulse wave velocity (PWV), blood pressure (BP)) and structural (carotid intima-media thickness, retinal microvascular calibre) preclinical cardiovascular phenotypes; lipids (total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides). Analysis: Linear regression (exposure: takeaway or SSB consumption, individually or together) adjusted for age, sex and socio-economic position; and mediation analysis for body mass index (BMI).

RESULTS

Associations were small among children (standardized mean difference (SMD) ≤0.15). In adults, associations were stronger with functional, but not structural, cardiovascular phenotypes and lipids, particularly for frequent takeaway food consumption (e.g. PWV (0.20 m/s; 95% confidence interval (CI) 0.03 to 0.37); systolic (3.3 mmHg; 95% CI 1.3 to 5.3) and diastolic BP (1.4 mmHg; 95% CI 0.2 to 2.6); LDL (0.10 mmol/L; 95% CI 0.02 to 0.18); HDL (-0.14 mmol/L; 95% CI -0.19 to -0.10) and triglycerides (0.30 mmol/L; 95% CI 0.12 to 0.48)]. BMI mediated associations between takeaway food consumption and PWV, BP, HDL and TG (proportion of mediation 34% to 75%), while mediation effects were smaller for SSB consumption.

CONCLUSIONS

Frequent takeaway food consumption in adults was associated with adverse blood lipids and vascular function (mainly via BMI). Lack of strong associations in children highlights opportunities for prevention.

Risk factors during first 1,000 days of life for carotid intima-media thickness in infants, children, and adolescents: A systematic review with meta-analyses

BACKGROUND

The first 1,000 days of life, i.e., from conception to age 2 years, could be a critical period for cardiovascular health. Increased carotid intima-media thickness (CIMT) is a surrogate marker of atherosclerosis. We performed a systematic review with meta-analyses to assess (1) the relationship between exposures or interventions in the first 1,000 days of life and CIMT in infants, children, and adolescents; and (2) the CIMT measurement methods.

METHODS AND FINDINGS

Systematic searches of Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica database (EMBASE), and Cochrane Central Register of Controlled Trials (CENTRAL) were performed from inception to March 2019. Observational and interventional studies evaluating factors at the individual, familial, or environmental levels, for instance, size at birth, gestational age, breastfeeding, mode of conception, gestational diabetes, or smoking, were included. Quality was evaluated based on study methodological validity (adjusted Newcastle-Ottawa Scale if observational; Cochrane collaboration risk of bias tool if interventional) and CIMT measurement reliability. Estimates from bivariate or partial associations that were least adjusted for sex were used for pooling data across studies, when appropriate, using random-effects meta-analyses. The research protocol was published and registered on the International Prospective Register of Systematic Reviews (PROSPERO; CRD42017075169). Of 6,221 reports screened, 50 full-text articles from 36 studies (34 observational, 2 interventional) totaling 7,977 participants (0 to 18 years at CIMT assessment) were retained. Children born small for gestational age had increased CIMT (16 studies, 2,570 participants, pooled standardized mean difference (SMD): 0.40 (95% confidence interval (CI): 0.15 to 0.64, p: 0.001), I2: 83%). When restricted to studies of higher quality of CIMT measurement, this relationship was stronger (3 studies, 461 participants, pooled SMD: 0.64 (95% CI: 0.09 to 1.19, p: 0.024), I2: 86%). Only 1 study evaluating small size for gestational age was rated as high quality for all methodological domains. Children conceived through assisted reproductive technologies (ART) (3 studies, 323 participants, pooled SMD: 0.78 (95% CI: -0.20 to 1.75, p: 0.120), I2: 94%) or exposed to maternal smoking during pregnancy (3 studies, 909 participants, pooled SMD: 0.12 (95% CI: -0.06 to 0.30, p: 0.205), I2: 0%) had increased CIMT, but the imprecision around the estimates was high. None of the studies evaluating these 2 factors was rated as high quality for all methodological domains. Two studies evaluating the effect of nutritional interventions starting at birth did not show an effect on CIMT. Only 12 (33%) studies were at higher quality across all domains of CIMT reliability. The degree of confidence in results is limited by the low number of high-quality studies, the relatively small sample sizes, and the high between-study heterogeneity.

CONCLUSIONS

In our meta-analyses, we found several risk factors in the first 1,000 days of life that may be associated with increased CIMT during childhood. Small size for gestational age had the most consistent relationship with increased CIMT. The associations with conception through ART or with smoking during pregnancy were not statistically significant, with a high imprecision around the estimates. Due to the large uncertainty in effect sizes and the limited quality of CIMT measurements, further high-quality studies are needed to justify intervention for primordial prevention of cardiovascular disease (CVD).

Body Mass Index From Early to Late Childhood and Cardiometabolic Measurements at 11 to 12 Years

OBJECTIVES

To examine how overweight and obesity at specific ages and overall BMI growth patterns throughout childhood predict cardiometabolic phenotypes at 11 to 12 years.

METHODS

In a population-based sample of 5107 infants, BMI was measured every 2 years between ages 2 to 3 and 10 to 11 years. We identified 5 BMI trajectories using growth curve models. At ages 11 to 12 years, 1811 children completed assessments for metabolic syndrome risk scores, carotid-femoral pulse wave velocity, and carotid intima-media thickness. Multivariable regression models were used to estimate associations, adjusted for potential confounders (eg, age, sex, smoking exposure, and small for gestational age).

RESULTS

Overweight and obesity from early childhood onward were strongly associated with higher cardiometabolic risk at 11 to 12 years of age. At age 6 to 7 years, compared with those with a healthy weight, children with overweight had higher metabolic syndrome risk scores by 0.23 SD units (95% confidence interval 0.05 to 0.41) and with obesity by 0.76 SD units (0.51-1.01), with associations almost doubling by age 10 to 11 years. Obese (but not overweight) children had higher outcome pulse wave velocity (0.64-0.73 SD units) from ages 6 to 7 years and slightly higher outcome carotid intima-media thickness (0.20-0.30 SD units) at all ages. Cumulative exposure to high BMI from 2 to 3 years of age carried the greatest cardiometabolic risk, with a gradient of risk across trajectories.

CONCLUSIONS

High early-childhood BMI is already silently associated with the development of cardiometabolic risk by 11 to 12 years, highlighting the urgent need for effective action to reduce overweight and obesity in early childhood.

In utero teratogen exposure and cardiometabolic risk in 5-year-old children: a prospective pediatric study

Background: Aorta and carotid intima-media thickness (IMT) is a measure of subclinical atherosclerosis and useful to assess cardiometabolic risk in the young. The in utero milieu may involve cardiometabolic programing and the development of cardiometabolic risk factors in children. Maternal smoking, alcohol consumption, and micronutrient deficiencies during pregnancy influence the development of the cardiovascular system through a process of DNA methylation.Aim: To explore an association between maternal smoking and alcohol consumption during pregnancy and intima media thickness in 5-year-old children for a low-income setting.Methods: Data were collected from 500 mother-child pairs at antenatal clinic visit, at birth, and at age 5 years. Anthropometric measurements were collected at birth and again at age 5 years. As well as clinical and ultrasound measurements at age 5 years. Clinical measurements, at age 5 years, included blood pressure, mean arterial pressure, and heart rate. Ultrasound measurements of the aorta and carotid arteries IMT were performed at age 5 years. Main outcome of interest was effect of dual teratogen exposure on the ultrasound measures IMT as indication of cardiometabolic risk.Results: cIMT was significantly higher in children exposed to both alcohol and nicotine during pregnancy compared to those not exposed (p = .008). In separate linear models, dual in utero exposure (beta = 0.12; p = .01) and male sex (beta = 0.14; p = .01) were associated with higher right cIMT values (F(6,445) = 5.20; R² = 0.07, p < .01); male sex (beta = 0.13; p = .01) and low birth weight (beta = 0.07; p = .01) with higher left cIMT value (F(4,491) = 4.49; R² = 0.04; p = .01); and males sex (beta = 0.11; p = .02) with higher aorta IMT (F(6,459) = 5.63; R² = 0.07; p < .01). Significant positive correlations between maternal measures of adiposity, maternal MUAC (r = 0.10; p = .03), and maternal BMI (r = 0.12; p < .01) and right cIMT measurements adjusted for the BMI of the child at age 5 years as covariate. Blood pressure measurements at age 5 years were not significantly associated with IMT but, instead, correlated significantly and positively with the BMI of the child at age 5 years (p < .01).Conclusion: Children exposed to both maternal smoking and alcohol consumption during pregnancy presented with cardiometabolic risk factors 5 years after birth. In addition, maternal adiposity, male sex, and low birth weight were associated with higher IMT at age 5 years.

A Cross-Cohort Study Examining the Associations of Metabolomic Profile and Subclinical Atherosclerosis in Children and Their Parents: The Child Health CheckPoint Study and Avon Longitudinal Study of Parents and Children

Background High-throughput nuclear magnetic resonance profiling of circulating metabolites is suggested as an adjunct for cardiovascular risk evaluation. The relationship between metabolites and subclinical atherosclerosis remains unclear, particularly among children. Therefore, we examined the associations of metabolites with carotid intima-media thickness ( cIMT ) and arterial pulse wave velocity ( PWV ). Methods and Results Data from two independent population-based studies was examined; (1) cross-sectional associations with cIMT and PWV in 1178 children (age 11-12 years, 51% female) and 1316 parents (mean age 45 years, 87% female) from the CheckPoint study (Australia); and (2) longitudinal associations in 4249 children (metabolites at 7-8 years, PWV at 10-11 years, 52% female), and cross-sectional associations in 4171 of their mothers (mean age 48 years, cIMT data) from ALSPAC (The Avon Longitudinal Study of Parents and Children; UK ). Metabolites were measured by the same nuclear magnetic resonance platform in both studies, comprising of 69 biomarkers. Biophysical assessments included body mass index, blood pressure, cIMT and PWV . In linear regression analyses adjusted for age, sex, body mass index, and blood pressure, there was no evidence of metabolite associations in either children or adults for cIMT at a 10% false discovery threshold. In CheckPoint adults, glucose was positively, and some high-density lipoprotein-cholesterol derived measures and amino acids (glutamine, histidine, tyrosine) inversely associated with PWV. Conclusions These data suggest that in children circulating metabolites have no consistent association with cIMT and PWV once adjusted for body mass index and blood pressure. In their middle-aged parents, some evidence of metabolite associations with PWV were identified that warrant further investigation.

Cross-sectional associations between Ideal Cardiovascular Health scores and vascular phenotypes in 11- to 12-year-olds and their parents: The Longitudinal Study of Australian Children

BACKGROUND

Understanding early-life relationships between the Ideal Cardiovascular Health (ICVH) score and vascular phenotypes could inform likely effectiveness and timing of cardiovascular disease prevention strategies. We aimed to describe associations between ICVH scores and vascular phenotypes in 11- to 12-year-old children and their parents.

METHODS AND RESULTS

Cross-sectional ICVH scores (range 0-7, higher indicating better health), derived by summing dichotomized metrics for cholesterol, glucose, blood pressure (BP), body mass index (BMI), diet, physical activity and smoking, were constructed for 1235 adults (89% female, mean age 43 years) and 1028 children (48% female, 12 years). The median scores were 4 and 5 for adults and children respectively. Child ICVH scores were associated with parent scores (0.18 higher child score per additional point in parent's score, 95% CI 0.12 to 0.22, P < 0.001). Each additional point in the adult ICVH score was associated with slower carotid-femoral pulse wave velocity (PWV, -0.32 m/s, 95% CI -0.37 to -0.27), greater carotid elasticity (0.017%/mm Hg, 95% CI 0.014 to 0.020) and reduced carotid intima-media thickness (IMT, -7.3 μm, 95% CI -12.0 to -2.5). An additional point in the child score was associated with functional phenotypes (PWV -0.07 m/s, 95% CI -0.11 to -0.03; carotid elasticity 0.009%/mm Hg, 95% CI 0.004 to 0.015) but not structural phenotypes (IMT -1.8 μm, 95% CI -5.2 to 1.5).

CONCLUSION

Few Australian children and even fewer parents have ideal cardiovascular health. Lower ICVH scores were associated with adverse adult vascular phenotypes and adverse child vascular function. Family-based interventions optimizing ICVH metrics may delay onset and progression of subclinical atherosclerosis and later cardiovascular disease.

High Blood Pressure at Early School Age Among Extreme Preterms

BACKGROUND AND OBJECTIVES

Former preterm infants are at increased risk of hypertension with increasing age. Our objective was to identify rates of high blood pressure (BP) (≥90th percentile) and hypertension (BP ≥95th percentile) and associated risk factors among extreme preterm (EPT) infants at 6 to 7 years of age.

METHODS

Assessment included BP and anthropometrics. Comparisons were made by BP ≥90th versus <90th percentile. Regressions were run to identify relative risk (RR) of factors associated with BP ≥90th percentile.

RESULTS

Among 379 EPT infants, 20.6% had systolic high BP, 10.8% systolic hypertension, 21.4% diastolic high BP, and 11.4% diastolic hypertension. Children with systolic high BP had higher rates of BMI, triceps skinfolds >85th percentile, and waist circumference >90th percentile. In regression analyses, weight gain velocity from 18 months to school age (RR = 1.36), and maternal gestational diabetes (MGD) (RR = 2.04) predicted systolic and either systolic and/or diastolic high BP (RR = 1.27 and RR = 1.67). Among children with BMI <85th percentile, 17% had systolic and 19% had diastolic high BP. Regression analysis for normal weight children indicated public insurance (RR = 2.46) and MGD (RR = 2.16) predicted systolic high BP, and MGD (RR = 2.08) predicted either systolic or diastolic high BP.

CONCLUSIONS

Both overweight and normal weight EPT children are at risk for high BP and hypertension. Public insurance, MGD, and weight gain velocity are risk factors. Findings of high BP among EPT children at early school age are worrisome and indicate a need for close follow-up.

Prevalence and Distribution of Atherosclerosis in a Low- to Intermediate-Risk Population: Assessment with Whole-Body MR Angiography

Purpose To quantify the burden and distribution of asymptomatic atherosclerosis in a population with a low to intermediate risk of cardiovascular disease. Materials and Methods Between June 2008 and February 2013, 1528 participants with 10-year risk of cardiovascular disease less than 20% were prospectively enrolled. They underwent whole-body magnetic resonance (MR) angiography at 3.0 T by using a two-injection, four-station acquisition technique. Thirty-one arterial segments were scored according to maximum stenosis. Scores were summed and normalized for the number of assessable arterial segments to provide a standardized atheroma score (SAS). Multiple linear regression was performed to assess effects of risk factors on atheroma burden. Results A total of 1513 participants (577 [37.9%] men; median age, 53.5 years; range, 40-83 years) completed the study protocol. Among 46 903 potentially analyzable segments, 46 601 (99.4%) were interpretable. Among these, 2468 segments (5%) demonstrated stenoses, of which 1649 (3.5%) showed stenosis less than 50% and 484 (1.0%) showed stenosis greater than or equal to 50%. Vascular stenoses were distributed throughout the body with no localized distribution. Seven hundred forty-seven (49.4%) participants had at least one stenotic vessel, and 408 (27.0%) participants had multiple stenotic vessels. At multivariable linear regression, SAS correlated with age (B = 3.4; 95% confidence interval: 2.61, 4.20), heart rate (B = 1.23; 95% confidence interval: 0.51, 1.95), systolic blood pressure (B = 0.02; 95% confidence interval: 0.01, 0.03), smoking status (B = 0.79; 95% confidence interval: 0.44, 1.15), and socioeconomic status (B = -0.06; 95% confidence interval: -0.10, -0.02) (P < .01 for all). Conclusion Whole-body MR angiography identifies early vascular disease at a population level. Although disease prevalence is low on a per-vessel level, vascular disease is common on a per-participant level, even in this low- to intermediate-risk cohort. © RSNA, 2018 Online supplemental material is available for this article.