The association of hypothalamic-pituitary-adrenal axis activity and blood pressure in an Afro-Caribbean population

Biomarkers of Cardiovascular Diseases in Saliva and Gingival Crevicular Fluid: A Review

Due to the fact that cardiovascular diseases (CVDs) have become the most serious problem in public health, there is a need for new and efficient methods for screening and early detection. In the recent literature, saliva and gingival crevicular fluid (GCF) have been gaining recognition as sources of many potential biomarkers of various systemic diseases, mainly because of correlation between the level of some compounds in the blood and saliva and association between the composition of saliva and health status. In this review, we summarize published findings of patients with atherosclerosis, arterial hypertension, coronary artery disease (CAD), acute coronary syndrome (ACS), and stroke in the context of clinical utility of saliva and GCF in diagnosing and assessing CVD severity. We hypothesize that substances in saliva including inflammatory markers, enzymes, or hormones might become novel contributors to the diagnosis and screening of CVDs. In particular, C-reactive protein (CRP), tumor necrosis alpha (TNFα), and cortisol seem to be the most promising. However, further investigation is warranted to determine the most effective markers and methods for their analysis.

Morning Serum Cortisol Is Uniquely Associated with Cardiometabolic Risk Independent of Body Composition in Latino Adolescents

Background: Alterations in morning serum cortisol (MSC) have been associated with higher cardiometabolic risk. This finding has been documented primarily in populations with overweight or obesity; however, it has not been clearly established if obesity plays a requisite role in this relationship. This study seeks to extend earlier findings by examining whether body composition measures alter the relationship between MSC with glucose and insulin markers, blood pressure, and lipid parameters in Latino youth in middle adolescence. Methods: This cross-sectional study included 196 healthy adolescents (130F/66M; mean age: 16.4 ± 0.6 years; 95% Latino; mean body mass index, BMI: 24.3 ± 5.7) from Los Angeles, California. Morning cortisol, glucose, insulin, glycated hemoglobin, and lipids (triglycerides and high-density lipoprotein cholesterol) were assessed from a fasting blood sample. Sitting systolic and diastolic blood pressure was averaged from duplicate measures. Body composition measures included BMI and waist circumference, which were used as proxies for total body and abdominal adiposity, respectively. Triplicate measurements of weight and height were averaged for calculation of BMI; age- and sex-specific BMI z-score was used to classify into normal BMI or overweight/obese BMI status. Waist circumference was measured in duplicate and the average was used to classify participants into two strata: normal/healthy waist circumference (<90th percentile for age, sex, and ethnicity) and high waist circumference (≥90th percentile). Results: The primary findings were that higher MSC was associated with higher fasting glucose and systolic blood pressure after adjusting for age, sex, and BMI z-score (and/or waist circumference). BMI status or waist circumference status did not alter these relationships. Main Conclusion: Our results suggest that the relationships between hypothalamic-pituitary-adrenal axis function and certain cardiometabolic risk factors may be independent of adiposity. Future research is warranted to discover the contributors and underlying mechanisms of these relationships in adolescent populations. ClinicalTrials.gov identifier: NCT02088294.

Neighbourhood characteristics and cumulative biological risk: evidence from the Jamaica Health and Lifestyle Survey 2008: a cross-sectional study

OBJECTIVE

To examine whether neighbourhood characteristics are associated with cumulative biological risk (CBR) and sex differences in CBR in a nationally representative sample in Jamaica, a small island developing country with increasing prevalence of non-communicable diseases (NCDs).

DESIGN

Cross-sectional study SETTING: A population-based cross-sectional survey, the Jamaica Health and Lifestyle Survey 2008 (JHLS II) recruited persons at their homes over a 4 month period from all 14 parishes and 113 neighbourhoods defined as enumeration districts (EDs).

PARTICIPANTS

2544 persons aged 15-74 years old from the 2008 Jamaica Health and Lifestyle Survey (JHLS II), who completed interviewer-administered questionnaires and had biomarkers assessed, and whose home addresses could be reliably geocoded.

PRIMARY OUTCOME

A summary measure CBR was created using seven markers-systolic and diastolic blood pressure readings, waist circumference, body mass index, total cholesterol, fasting blood glucose levels and self-reported asthma. Weighted multilevel models examined clustering, using the intraclass correlation coefficient (ICC), of CBR across neighbourhoods and the impact of neighbourhood characteristics (recreational space availability and neighbourhood disorder) on CBR.

RESULTS

Women had significantly higher mean CBR scores than men across all age groups. There was significant clustering of CBR by ED, and among women versus men (ICC: F=6.9%, M=0.7%). Women living in more disordered neighbourhoods were 26% more likely to have high CBR as those in less disordered ones (aOR=1.26, 95% CI=1.08 to 1.47; p<0.05). Individuals living in EDs with greater recreational space availability were 25% less likely to have a high CBR (aOR=0.75, 95% CI=0.64 to 0.90; p<0.05).

CONCLUSIONS

Policy-makers in Jamaica should pay greater attention to neighbourhood factors such as recreational space availability and neighbourhood disorder that may contribute to CBR in any effort to curtail the epidemic of NCDs.

Children's stress-related reports and stress biomarkers interact in their association with metabolic syndrome risk

The purpose was to examine the cross-sectional associations of stress-related reports and stress biomarkers with metabolic syndrome (MetS) risk in children while also testing the interaction between stress biomarkers and stress reports. In 353 children (5-10 years old, 7.9% overweight/obese), MetS risk was measured by blood pressure, waist circumference, glucose homeostasis, triglycerides, and high-density cholesterol. Stress was measured by stress-related reports (events, emotions, and internalizing/externalizing problems) and two biomarkers: salivary cortisol (total-day and morning output) and heart rate variability (percentage of consecutive normal RR intervals differing more than 50 ms and low-to-high-frequency ratio). Cross-sectional regression analyses with z scored total MetS risk as outcome were adjusted for age, sex, and socio-economic status. Only internalizing problems were directly related to a higher MetS risk score (β = 0.236). Cortisol and heart rate variability were significant moderators: High cortisol morning output resulted in a positive (unfavourable) report-MetS relationship (β = 0.259-0.552), whereas low percentage of consecutive normal RR intervals differing more than 50 ms resulted in a negative (favourable) report-MetS relationship (β = -0.298) and low low-to-high-frequency ratio in a positive (unfavourable) report-MetS relationship (β = 0.478). In conclusion, stress can sometimes be a disadvantageous factor in metabolic health of otherwise healthy children. The cortisol biomarker seems relevant because metabolic risk was highest when stress-related reports were accompanied by high morning cortisol output.

Defensive coping facilitated a smaller cortisol-to-estradiol ratio and a higher hypertension risk: the SABPA study

OBJECTIVES

Taxing psychosocial stress and defensive coping have been associated with hypoactivity in cortisol, a vasoconstrictive agent. Estradiol has vasodilatory properties with cardio- and neuroprotective effects. It can however also induce α₁-adrenergic vasoconstrictive responsiveness. We aimed to determine whether the cortisol-to-estradiol ratio (Cort:E2) may augment α₁-adrenergic responsiveness and hypertension risk when habitually using defensive coping.

METHODS

African (n = 168) and Caucasian (n = 207) men and women (46 ± 9 years) were included. Preferential use of defensive coping was determined from Coping Strategy Indicator questionnaire scores. 24h Ambulatory blood pressure was obtained. Fasting serum estradiol and cortisol samples were collected before 09h00 and Cort:E2 was calculated.

RESULTS

Estradiol was higher in ethnic-coping groups. Smaller Cort:E2, higher estradiol levels, self-reported emotional stress (19.05% vs. 9.66%) and 24h blood pressure reaching hypertensive status (65% vs. 24%) were evident in African compared to Caucasian men (p ≤ .05). A smaller Cort:E2 was associated with augmented 24h SBP and 24h DBP in African men [Adj R² 0.21-0.29 (p ≤ .05)], and especially when utilizing defensive coping [Adj R² 0.34-0.38 (p ≤ .001)].

CONCLUSIONS

A smaller Cort:E2 was associated with raised blood pressure in defensive coping African men. Defensive coping, possibly via highly activated α₁-adrenergic vasoconstrictive responses, may facilitate neuro-endocrine dysfunction and hypertension in African men.

Maternal verbally aggressive behavior in early infancy is associated with blood pressure at age 5–6

Early life stress has been shown to contribute to alterations in biobehavioral regulation. Whereas many different forms of childhood adversities have been studied in relation to cardiovascular outcomes, very little is known about potential associations between caregivers’ verbally aggressive behavior and heart rate and blood pressure in the child. This prospective study examined whether maternal verbally aggressive behavior in early infancy is associated with heart rate or blood pressure at age 5–6. In the Amsterdam Born Children and their Development study, a large prospective, population-based birth cohort, maternal verbally aggressive behavior was assessed by questionnaire in the 13th week after birth. The child’s blood pressure and heart rate were measured during rest at age 5–6 (n=2553 included). Maternal verbally aggressive behavior in infancy was associated with a higher systolic blood pressure (SBP) both in supine and sitting position after adjustment for sex, height and age (SBP supine B=1.01 mmHg; 95% CI [0.06; 1.95] and SPB sitting B=1.29 mmHg; 95% CI [0.12; 2.46]). Adjustment for potential confounding variables, such as other mother–infant dyad aspects, family hypertension and child’s BMI, only slightly attenuated the associations (SBP supine B=0.99 mmHg; 95% CI [0.06; 1.93] and SPB sitting B=1.11 mmHg; 95% CI [−0.06; 2.27]). Maternal verbally aggressive behavior was not associated with diastolic blood pressure or heart rate at age 5–6. Maternal verbally aggressive behavior might be an important early life stressor with negative impact on blood pressure later in life, which should be further investigated. Possible underlying mechanisms are discussed.

Prenatal glucocorticoid exposure programs adrenal PNMT expression and adult hypertension

Prenatal exposure to glucocorticoids (GCs) programs for hypertension later in life. The aim of the current study was to examine the impact of prenatal GC exposure on the postnatal regulation of the gene encoding for phenylethanolamine N-methyltransferase (PNMT), the enzyme involved in the biosynthesis of the catecholamine, epinephrine. PNMT has been linked to hypertension and is elevated in animal models of hypertension. Male offspring of Wistar-Kyoto dams treated with dexamethasone (DEX) developed elevated systolic, diastolic and mean arterial blood pressure compared to saline-treated controls. Plasma epinephrine levels were also elevated in adult rats exposed to DEX in utero. RT-PCR analysis revealed adrenal PNMT mRNA was higher in DEX exposed adult rats. This was associated with increased mRNA levels of transcriptional regulators of the PNMT gene: Egr-1, AP-2, and GR. Western blot analyses showed increased expression of PNMT protein, along with increased Egr-1 and GR in adult rats exposed to DEX in utero. Furthermore, gel mobility shift assays showed increased binding of Egr-1 and GR to DNA. These results suggest that increased PNMT gene expression via altered transcriptional activity is a possible mechanism by which prenatal exposure to elevated levels of GCs may program for hypertension later in life.

Association of maternal blood pressure in pregnancy with blood pressure of their offspring through adolescence

This article looks at the association of maternal blood pressure with the blood pressure of the offspring from birth to childhood. The Barker hypothesis states that maternal and "in utero" attributes during pregnancy affect a child's cardiovascular health throughout life. We present an analysis of a unique dataset that consists of three distinct developmental processes: maternal cardiovascular health during pregnancy; fetal development; and child's cardiovascular health from birth to 14 years. This study explored whether a mother's blood pressure reading in pregnancy predicts fetal development and determines if this in turn is related to the future cardiovascular health of the child. This article uses data that have been collected prospectively from a Jamaican cohort which involves the following three developmental processes: (1) maternal cardiovascular health during pregnancy which is the blood pressure and anthropometric measurements at seven time-points on the mother during pregnancy; (2) fetal development which consists of ultrasound measurements of the fetus taken at six time-points during pregnancy; and (3) child's cardiovascular health which consists of the child's blood pressure measurements at 24 time-points from birth to 14 years. The inter-relationship of these three processes was examined using linear mixed effects models. Our analyses indicated that attributes later in childhood development, such as child's weight, child's baseline systolic blood pressure (SBP), age and sex, predict the future cardiovascular health of children. The results also indicated that maternal attributes in pregnancy, such as mother's baseline SBP and SBP change, predicted significantly child's SBP over time.

Salivary Biomarkers of Chronic Psychosocial Stress and CVD Risks

Background:

The use of salivary biomarkers in stress research is increasing, and the precision and accuracy with which researchers are able to measure these biomarkers have dramatically improved. Chronic psychosocial stress is often linked to the pathogenesis of cardiovascular disease (CVD). Salivary biomarkers represent a noninvasive biological method of characterizing the stress phenomenon that may help to more fully describe the mechanism by which stress contributes to the pathogenesis and outcomes of CVD.

Objectives:

We conducted a systematic review of 40 research articles to identify the salivary biomarkers researchers have most commonly used to help describe the biological impact of chronic psychosocial stress and explore its associations with CVD risk. We address strengths and weaknesses of specimen collection and measurement.

Methods:

We used PubMed, CINAHL, EBSCO host, Web of Science, BIOSIS Previews, Biological Sciences (ProQuest), and Dissertations/Theses (ProQuest) to retrieve 387 initial articles. Once we applied our inclusion/exclusion criteria to specifically target adult human studies dealing with chronic stress rather than acute/laboratory-induced stress, 40 studies remained, which we synthesized using Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria.

Results:

Cortisol was the biomarker used most frequently. Sources of psychosocial stress included job strain, low socioeconomic status, and environmental factors. Overall, psychosocial stress was associated with CVD risks such as vascular pathology (hypertension, blood pressure fluctuation, and carotid artery plaque) as well as metabolic factors such as abnormal blood glucose, dyslipidemia, and elevated cardiac enzymes.

Conclusion:

Diverse salivary biomarkers have been useful in stress research, particularly when linked to CVD risks.

Defensive coping and renovascular disease risk - Adrenal fatigue in a cohort of Africans and Caucasians: The SABPA study

BACKGROUND

Defensive coping is an established cardiovascular risk factor in Africans. Additionally, chronic, excessive or inadequate hypothalamic-pituitary-adrenal axis (HPAA) stress responses could either increase or decrease cortisol responses, which may relate to renal impairment. We scrutinised the relationship between urinary cortisol levels and renovascular disease risk in Africans and Caucasians utilising defensive coping.

METHODS

Africans (n=168) and Caucasians (n=207) from the SABPA (Sympathetic activity and Ambulatory Blood Pressure in Africans) study were included in our analyses, excluding HIV positive, diabetic, renal impairment, and cortisone users. The Coping Strategy Indicator questionnaire assessed preferred coping responses. Ambulatory blood pressure was recorded together with 8h fasting blood and urine sampling. Renovascular disease risk markers included the albumin-to-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR).

RESULTS

The main findings revealed that Caucasians with high cortisol showed augmented renovascular disease risk. Conversely, Africans revealed low cortisol levels whilst 21.84% reported experience of severe stress, possibly depicting HPAA hypoactivity. Additionally, these Africans with low cortisol revealed increased ACR and decreased eGFR, which was further enhanced by defensive coping.

CONCLUSIONS

Defensive coping enhanced renovascular risk in Africans, especially in those with lower cortisol, which may be due to HPAA dysfunction and/or adrenal fatigue.

Early-life factors are associated with nocturnal cortisol and glucose effectiveness in Afro-Caribbean young adults

CONTEXT

Early-life factors (including intrauterine growth retardation) may influence the development of type 2 diabetes. We postulated that birth size is associated with cortisol levels, which itself could alter serum adipomyokines (i.e. adiponectin, IGF-I, myostatin) and glucose metabolism.

DESIGN

An observational study with 60 Afro-Caribbean young adults from a birth cohort.

MEASUREMENTS

Fasting blood was drawn for serum adiponectin, IGF-I and myostatin. A frequently sampled intravenous glucose tolerance test measured insulin sensitivity (SI), acute insulin response (AIRg), disposition index (DI) and glucose effectiveness (Sg). Body composition was assessed by dual-energy X-ray absorptiometry. Salivary cortisol was collected at home at 0800 and 2300 h. Sex-adjusted correlations were used to explore the relationships between birth size, cortisol and the metabolic variables.

RESULTS

The participants were 55% male, mean age 23·1 ± 0·5 years. Birth weight correlated positively with 2300-h cortisol (P = 0·04), although not after adjusting for gestational age. Gestational age was correlated with 2300 h cortisol (r = 0·38, P = 0·03), even after adjusting for birth weight (P = 0·02). 2300 h cortisol was not associated with adiponectin, IGF-I, myostatin, SI, AIRg or DI, but was negatively correlated with Sg (r = -0·30, P = 0·05) even after adjusting for birth and adult anthropometry. Adiponectin, IGF-I and myostatin were unrelated to glucose metabolism.

CONCLUSIONS

Gestational age is associated with higher nocturnal cortisol, which in turn is associated with lower glucose effectiveness in adulthood. Higher glucose effectiveness could therefore be a compensatory mechanism to improve glucose uptake.

Gender-specific alterations in salivary cortisol levels in pubertal intracytoplasmic sperm injection offspring

BACKGROUND

There is accumulating evidence that in vitro conception in humans may be associated with adverse health outcomes later in life. It has been proposed that suboptimal early life conditions may 'program' key endocrine systems. A disturbance of the hypothalamic-pituitary-adrenal (HPA) axis leading to alterations in cortisol secretion in the offspring may be such a mechanism. To date, no data on cortisol levels in children conceived by intracytoplasmic sperm injection (ICSI) are available in the literature.

METHODS

In this cross-sectional study, salivary cortisol known as a key regulator of metabolism was measured and results were compared between 201 pubertal ICSI children and 196 spontaneously conceived (SC) counterparts.

RESULTS

ICSI females had lower mean salivary cortisol levels (9.0 µg/l; 95% CI 8.1-9.9) than SC females (10.6 µg/l; 95% CI 9.7-11.5; p = 0.01). This difference remained after adjusting for current characteristics, early life factors and maternal characteristics. In ICSI males, no difference in cortisol levels was found in comparison with the SC group.

CONCLUSION

In our study, 14-year-old female but not male ICSI teenagers were found to have lower salivary cortisol concentrations in comparison with SC peers. However, before definite conclusions can be drawn, our results should be completed by longitudinal sampling.

Impaired cardiovascular structure and function in adult survivors of severe acute malnutrition

Malnutrition below 5 years remains a global health issue. Severe acute malnutrition (SAM) presents in childhood as oedematous (kwashiorkor) or nonoedematous (marasmic) forms, with unknown long-term cardiovascular consequences. We hypothesized that cardiovascular structure and function would be poorer in SAM survivors than unexposed controls. We studied 116 adult SAM survivors, 54 after marasmus, 62 kwashiorkor, and 45 age/sex/body mass index-matched community controls who had standardized anthropometry, blood pressure, echocardiography, and arterial tonometry performed. Left ventricular indices and outflow tract diameter, carotid parameters, and pulse wave velocity were measured, with systemic vascular resistance calculated. All were expressed as SD scores. Mean (SD) age was 28.8±7.8 years (55% men). Adjusting for age, sex, height, and weight, SAM survivors had mean (SE) reductions for left ventricular outflow tract diameter of 0.67 (0.16; P<0.001), stroke volume 0.44 (0.17; P=0.009), cardiac output 0.5 (0.16; P=0.001), and pulse wave velocity 0.32 (0.15; P=0.03) compared with controls but higher diastolic blood pressures (by 4.3; 1.2-7.3 mm Hg; P=0.007). Systemic vascular resistance was higher in marasmus and kwashiorkor survivors (30.2 [1.2] and 30.8 [1.1], respectively) than controls 25.3 (0.8), overall difference 5.5 (95% confidence interval, 2.8-8.4 mm Hg min/L; P<0.0001). No evidence of large vessel or cardiac remodeling was found, except closer relationships between these indices in former marasmic survivors. Other parameters did not differ between SAM survivor groups. We conclude that adult SAM survivors had smaller outflow tracts and cardiac output when compared with controls, yet markedly elevated peripheral resistance. Malnutrition survivors are thus likely to develop excess hypertension in later life, especially when exposed to obesity.

Longitudinal relationships between diet-dependent renal acid load and blood pressure development in healthy children

Diets high in sulfur-rich protein and low in fruits and vegetables affect human acid-base balance adversely. Corresponding subclinical forms of metabolic acidosis have been linked to hypertension in adults. We longitudinally examined relations of dietary acid load with blood pressure in 257 healthy prepuberty children with 3 or more parallel 3-day weighed dietary records, 24-h urine, and blood pressure measurements. Urinary net acid excretion and the potential renal acid load (PRAL), determined as the difference of major urinary nonbicarbonate anions and mineral cations, were used to predict dietary acid load. PRAL was also calculated from dietary data. In repeated-measures regression analyses, adjusted for body size and dietary fiber, an intraindividual increase of 10 mEq above the 'usual' net acid excretion or urine PRAL were each significantly related to a 0.6-0.7 mm Hg increased systolic blood pressure. Differences in urine PRAL among the children also significantly predicted between-person differences in systolic blood pressure. A higher individual net acid excretion or urine PRAL and intraindividual increase in urine PRAL were significantly related to higher diastolic blood pressure. Blood pressure associations were nonsignificant for dietary PRAL and urinary sodium. Thus, in healthy children, renal biomarker analyses reveal an association of proton load with higher blood pressure. Especially for systolic blood pressure, a more alkalizing nutrition may be beneficial for blood pressure development within a given individual. Experimental confirmation of a causal acid load-blood pressure link is required.

11β Hydroxysteroid dehydrogenase type 2 and dietary acid load are independently associated with blood pressure in healthy children and adolescents

BACKGROUND

The reduced activity of 11β hydroxysteroid dehydrogenase type 2 (11βHSD2) contributes to elevated blood pressure (BP) in clinical syndromes, but its effect on BP in the physiologic range is unclear.

OBJECTIVES

We examined the association of 11βHSD2 activity with BP in healthy children independent of known BP-related dietary and other factors and determined whether the diet-dependent acid load may constitute a dietary factor related to BP.

DESIGN

We conducted a cross-sectional analysis in 267 healthy children (age range: 4-14 y) who provided a 24-h urine sample, a parallel 3-d weighed dietary record, and 1-3 BP measurements ±1.5 y around the urine collection. The ratio of urinary free cortisone to cortisol measured by using a radioimmunoassay was used as an index for 11βHSD2. Urinary net acid excretion and the urinary and dietary potential renal acid load (PRAL) were used to predict the diet-dependent acid load. The PRAL was calculated as the sum of major mineral nonbicarbonate anions minus the sum of mineral cations. Sex-, age- and height-independent SD scores (SDSs) of systolic and diastolic BP were used as outcomes in linear regression analyses.

RESULTS

11βHSD2 was inversely associated with systolic BP SDSs in basic models and in analyses adjusted for body size, maternal BP, breastfeeding, and dietary intakes of total energy, salt, and fruit and vegetables (P = 0.03). In models that included indexes of dietary acid load instead of fruit and vegetables, all 3 acid-load biomarkers were significantly (P = 0.006-0.02) directly related to systolic BP.

CONCLUSION

A lower 11βHSD2 activity and higher dietary acid load may independently contribute to higher systolic BP in healthy children.

The impact of maternal cortisol concentrations on child arterial elasticity

Epidemiological studies suggest that glucocorticoid excess in the fetus may contribute to the pathophysiology of cardiovascular diseases in adulthood. However, the impact of maternal glucocorticoid on the cardiovascular system of the offspring has not been much explored in studies involving humans, especially in childhood. The objective of this study was to assess the influence of maternal cortisol concentrations on child arterial elasticity. One hundred and thirty pregnant women followed from 1997 to 2000, and respective children 5–7 years of age followed from 2004 to 2006 were included in the study. Maternal cortisol was determined in saliva by an enzyme immunoassay utilizing the mean concentration of nine samples of saliva. Arterial elasticity was assessed by the large artery elasticity index (LAEI; the capacitive elasticity of large arteries) by recording radial artery pulse wave, utilizing the equipment HDI/PulseWave CR-2000 Cardiovascular Profiling System®. The nutritional status of the children was determined by the body mass index (BMI). Insulin concentration was assessed by chemiluminescence, and insulin resistance by the homeostasis model assessment. Blood glucose, total cholesterol and fractions (LDL-c and HDL-c) and triglyceride concentrations were determined by automated enzymatic methods. The association between maternal cortisol and child arterial elasticity was assessed by multivariate linear regression analysis. There was a statistically significant association between maternal cortisol and LAEI (P= 0.02), controlling for birth weight, age, BMI and HDL-c of the children. This study suggests that exposure to higher glucocorticoid concentrations in the prenatal period is associated to lower arterial elasticity in childhood, an earlier cardiovascular risk marker.

Morning cortisol is not associated with truncal fatness or resting blood pressure in children: cross-sectional and 1-2 year follow-up analyses

OBJECTIVE

To evaluate the cross-sectional and longitudinal relationships of morning cortisol with trunk fat and resting blood pressure (BP) in children.

METHODS

Participants included 72 children aged 4-10 years (mean 7.4 yrs) for the cross-sectional analysis and 58 for the longitudinal analysis. Height, weight, waist circumference, body fat by dual x-ray absorptiometry, and resting BP measures were obtained during a laboratory visit. Saliva samples were collected at home on a single morning and assayed for cortisol.

RESULTS

Approximately 21% were overweight (15.3%) or obese (5.6%). Mean morning cortisol was 0.25 +/- 0.12 microg/dL (6.99 +/- 3.46 nmol/L). There were no significant correlations between morning cortisol and any of the measures of fatness (r < -0.17) or BP (r < -0.10) at baseline. Cortisol at baseline was not associated with changes in body size parameters after the 1- and 2-year followup period.

CONCLUSION

Morning cortisol was not associated with body fatness or BP. Future studies should examine the associations between the diurnal cortisol patterns, trunk fat, and BP by collecting samples throughout an entire day.

Developmental origins of cardiovascular risk in Jamaican children: The Vulnerable Windows Cohort Study

Both intra-uterine and early childhood development contribute to the risk of developing CVD in adult life. We therefore evaluated the maternal, placental, fetal, birth, infant and childhood determinants of cardiovascular risk in a cohort of Afro-Jamaican children. The Vulnerable Windows Cohort is a longitudinal survey of 569 mothers and their offspring recruited from the first trimester. The offspring's anthropometry was measured at birth, at 6 weeks, every 3 months to 1 year and then every 6 months. At mean age 11·5 years, fasting blood was sampled for glucose, insulin and lipids. Analyses were confined to 296 women and their offspring who had complete data. Waist circumference (WC) was related to maternal weight and BMI, placental weight and to the size of the offspring in utero, at birth and the rate of growth in childhood (P < 0·05). Total cholesterol, TAG and glucose concentrations were unrelated to maternal, placental, fetal, neonatal and childhood measurements. Fasting insulin and homeostasis model assessment of insulin resistance were related to maternal weight and BMI (P < 0·05), but not after adjusting for WC. HDL-cholesterol was inversely related to placental and birth weight, and inversely related to weight and BMI throughout childhood (P < 0·001), but not after adjusting for WC. Systolic blood pressure was directly related to maternal weight, child's height, weight and BMI (P < 0·05), but not after adjustment for WC. Systolic blood pressure and fasting glucose concentration were inversely related to birth weight in boys but directly associated in girls. We concluded that maternal anthropometry during pregnancy, fetal size, and childhood growth rate contribute to cardiovascular risk factors in childhood.