Age-related patterns of the clustering of cardiovascular risk variables of syndrome X from childhood to young adulthood in a population made up of black and white subjects: the Bogalusa Heart Study

Insulin and obstructive sleep apnea in obese Chinese children

OBJECTIVE

In adults, obstructive sleep apnea (OSA) is associated with insulin resistance and dyslipidemia. We aimed to establish correlation between OSA, serum lipid profile, and insulin levels in obese snoring children.

METHODS

Consecutive obese children with habitual snoring were recruited. They underwent physical examination, overnight polysomnography (PSG), and metabolic studies. OSA was diagnosed if apnea hypopnea index (AHI) > 1.0, and cases were considered to have moderate to severe OSA if AHI > 10.

RESULTS

Ninety-four obese subjects with habitual snoring were studied. Seventy-three subjects were male and the median age of the studied group was 12.0 years (IQR 9.7-13.9). None of the subjects had active cardiopulmonary disease, and the BMI values of our subjects were >95th percentile using local reference charts. Sixty subjects had OSA, 47 being mild, and 13 being moderate to severe OSA. Multiple logistic regression analysis revealed that saturation nadir and insulin levels were significantly associated with OSA.

CONCLUSION

OSA is prevalent among obese children with habitual snoring and insulin is independently associated with the condition. Its role in the cardiovascular complications of childhood sleep apnea is worthy of further exploration.

Association of hematological factors with components of the metabolic syndrome in older and younger adults

BACKGROUND AND AIMS

This study retrospectively examined the characteristics of metabolic syndrome in an aged population and assessed the risk factors for these subjects.

METHODS

A total of 1332 aged subjects (> or =65 years; mean age 71.0+/-5.0 years) were enrolled from 6903 subjects recruited from the Department of Health Management at Chang Gung Medical Center. Of these 6903 subjects, 1665 (814 females and 851 males) were diagnosed with metabolic syndrome. Whole body three-dimensional (3- D) laser scanning was employed for anthropometric measurements. Furthermore, health index (HI) was derived by the following equation: HI = (body weight x 2 x waist area) / [body height2 x (breast area + hip area)].

RESULTS

Among the 6903 subjects, no significant difference in gender was noted between groups with and without metabolic syndrome (p=0.142). For subjects >64 years, the incidence of metabolic syndrome in females is higher than in males. Subjects are categorized into four groups based on age and whether they had metabolic syndrome. Group A (4402 cases) consists of subjects <65 years old without metabolic syndrome. Group B (836 cases) comprises subjects >64 years old and without metabolic syndrome. Group C (1169 cases) contains subjects <65 years old with metabolic syndrome and group D (496 cases) is composed of subjects >64 years old with metabolic syndrome. Of the aged 1332 subjects, 595 were females (mean age, 70.6+/-4.6 years) and 737 were males (mean age, 71.3+/-5.3years), 37.2% (496/1332) had metabolic syndrome, 19.9% had DM and 21.8% had hypertension. These subjects had decreased BMI with age. Additionally, WHR peaked at an age range of 75-79 years. Of the aged subjects, also overweight, 42.8% and 33.6% were diagnosed with hypertension and DM, respectively; both ratios higher than those for non-overweight subjects (25.3% and 26.2%, respectively). Of the four groups in this study, the ratios for DM, hypertension, and WHR, HI, and LDL levels progressively increased through groups A to D. WBC count differs statistically significantly between these groups. Statistical analysis of WBC count, RBC and hemoglobin (Hb) with different parameters demonstrates significant elevation of WBC counts with the components of metabolic syndrome in aged subjects.

CONCLUSIONS

WBC count, RBC count and Hb are associated with metabolic syndrome components in younger and old adults of both genders. The incidence of metabolic syndrome marker increased after menopause onset in the female population in this study.

Follow-up on metabolic markers in children treated for obstructive sleep apnea

RATIONALE

In adults, obstructive sleep apnea (OSA) is associated with metabolic dysfunction that improves with treatment of OSA. No equivalent studies exist in children.

OBJECTIVE

To examine the relationship between metabolic markers and OSA with time and treatment in children.

METHODS

Metabolic markers measured on a fasting morning blood sample at diagnostic polysomnography and follow-up 1.3 +/- 0.6 yr later.

MEASUREMENTS AND MAIN RESULTS

Forty-five children (34 males), aged 6.9 +/- 3.5 yr, and including 12 obese subjects, were in the final analysis. There were no differences in metabolic markers between children with and without OSA at initial study; however, obese children had significantly higher insulin (106.1 +/- 72.1 vs. 66.7 +/- 37.6 pmol/L; p = 0.028), insulin/glucose ratio (23.7 +/- 14.3 vs. 14.7 +/- 8.0; p = 0.02), and significantly lower high-density lipoprotein cholesterol (1.3 +/- 0.2 vs. 1.6 +/- 0.4 nmol/L; p = 0.005) than nonobese children. Twenty children underwent surgical removal of adenotonsillar tissue, whereas 12 children with OSA elected not to have treatment. OSA persisted after treatment in five children, and resolved in 27. Thirteen children did not have OSA on initial or follow-up studies. At follow-up, there was a small but significant improvement in total cholesterol in those children whose OSA was resolved (4.8 +/- 0.8 to 4.7 +/- 0.6 nmol/L; p = 0.005) and a trend for obese children with persisting OSA to have elevated insulin levels compared with obese children without OSA (p = 0.07).

CONCLUSION

Obesity appears to be the major influence on metabolic dysfunction in children with OSA, but these preliminary data also suggest that resolution or persistence of OSA may affect changes in metabolic function over time.

Obesity in youth is not an independent predictor of carotid IMT in adulthood

Being obese in childhood may be associated with increased cardiovascular morbidity and mortality in adulthood. We examined the relationship between obesity and overweight identified in youth and carotid artery intima-media thickness assessed in adulthood. As part of the longitudinal Cardiovascular Risk in Young Finns Study, we assessed tracking of body mass index (BMI) from youth (ages 3-18 years) to young adulthood (ages 24-39 years) in a cohort of 2,260 subjects. BMI measured in youth was significantly associated with BMI measured in adulthood. The risk of being obese in adulthood (BMI > 30 kg/m(2)) was increased by three-fold in subjects who had been overweight or obese (BMI > 80th percentile) in childhood (ages 3-9 years) and by four-fold in subjects who had been overweight or obese in adolescence (ages 12-18 years). Age and sex adjusted adult IMT values were comparable in subjects who had been consistently overweight/obese in youth and adulthood and in subjects who became obese in adulthood, 0.642 mm versus 0.634 mm, respectively. IMT values were lower (overall P < 0.0001) and comparable in subjects who had remained consistently non-obese and those who had been obese in youth but had become non-obese in adulthood, 0.610 mm versus 0.627 mm, respectively. We conclude that being obese in youth is associated with increased carotid IMT in adulthood, but this relationship is explained by significant tracking of body mass from youth to adulthood.

Accelerometry-measured activity or sedentary time and overweight in rural boys and girls

OBJECTIVE

The aim of this study was to examine the association between overweight and physical activity or sedentary time measured by accelerometry in rural boys and girls 7 to 19 years old.

RESEARCH METHODS AND PROCEDURES

A cross-sectional study was conducted involving 130 girls and 99 boys in elementary, middle, and high school in rural Maryland. After weight, height, and body composition were measured, children wore an Actiwatch accelerometer for 6 days. Comparisons for activity counts were made between normal and overweight or at risk for overweight (at-risk/overweight) participants (>or=85th percentile of BMI). The associations between body composition and accelerometry-defined activity levels (sedentary, light, moderate, and vigorous) were analyzed by age group for boys and girls.

RESULTS

Differences in total activity in counts per day or counts per minute were not observed between normal and at-risk/overweight boys or girls in all age groups. No associations between measures of body composition and time spent in an activity level were seen in boys. Fat mass and percentage fat were positively correlated to time spent in sedentary activity (range r = 0.42 to 0.54, all p < 0.01) for girls. In contrast, fat mass and percentage fat were negatively related to time spent in light activity (range, r = -0.40 to -0.51, p < 0.05) for girls.

DISCUSSION

In girls, but not boys, greater body fat is associated with greater time spent being inactive, and lower levels of body fat are associated with more time spent in light activity. Physical activity interventions targeting inactive children in rural communities are warranted.

Obstructive sleep-disordered breathing and fasting insulin levels in nonobese children

A positive correlation of severity of sleep-disordered breathing with morning fasting insulin levels, which is independent of obesity, was reported in adults and obese children. We hypothesized that both severity of sleep-disordered breathing and relative body mass index predict fasting insulin and homeostasis model assessment (HOMA) index values in nonobese children with habitual snoring. One hundred and ten subjects with habitual snoring (median age, 6 years; range, 2-13 years) underwent polysomnography and measurement of morning fasting insulin and glucose levels. The HOMA index was calculated. Thirty children had an apnea-hypopnea index (AHI) >/= 5 episodes/hr (median, 7.8 episodes/hr; range, 5-42.3 episodes/hr), and 80 subjects had an AHI < 5 episodes/hr (median, 1.9 episodes/hr; range, 0.2-4.9 episodes/hr). Insulin and HOMA index values were similar in children with AHI >/= 5 episodes/hr (median insulin, 4.9 mU/l; range, 1.66-19.9 mU/l; and median HOMA, 1; range, 0.36-4.95) and in subjects with AHI < 5 episodes/hr (median insulin, 5.8 mU/l; range, 0.74-41.1 mU/l; and median HOMA, 1.3; range, 0.13-9.72) (P > 0.05). No significant correlations were identified between insulin or HOMA index values and any polysomnography indices (P > 0.05). When multiple linear regression was carried out, relative body mass index was a significant predictor of log-transformed insulin levels or HOMA index values, but AHI and percentage of sleep time with saturation <95% were not. In conclusion, contrary to findings in adults and in obese children, severity of sleep-disordered breathing is not a significant predictor of fasting insulin or HOMA index values in nonobese children with habitual snoring.

Pediatric obesity and insulin resistance: chronic disease risk and implications for treatment and prevention beyond body weight modification

The study of childhood obesity has continued to grow exponentially in the past decade. This has been driven in part by the increasing prevalence of this problem and the widespread potential effects of increased obesity in childhood on lifelong chronic disease risk. The focus of this review is on recent findings regarding the link between obesity and disease risk during childhood and adolescence. We describe recent reports relating to type 2 diabetes in youth (2), prediabetes (69, 166), metabolic syndrome (33, 35), polycystic ovarian syndrome (77), and nonalcoholic fatty liver disease (58, 146), and the mediating role of insulin resistance in these conditions. In addition, we review the implications of this research for the design of more effective treatment and prevention strategies that focus more on the improvement of obesity-related metabolic abnormalities and chronic disease risk reduction than on the conventional energy balance approach that focuses on weight management.

Obesity in childhood and vascular changes in adulthood: insights into the Cardiovascular Risk in Young Finns Study

AIMS

Exposure to risk factors in childhood may have long-term influences on vascular structure and function. This paper reviews recent findings from the Cardiovascular Risk in Young Finns Study looking at the relationships between risk factors identified in childhood, including obesity, and arterial structure/function assessed in adulthood.

METHODS

The Young Finns Study is a longitudinal study from childhood to adulthood. The baseline study was carried out in 980 and included 3.596 children and adolescents aged 3-18y. Regular follow-up examinations of this cohort have included comprehensive data collection, including obesity indices (body mass index (BMI, kg/m2) and skinfolds in childhood), serum lipoproteins, insulin, glucose, blood pressure, family risk, lifestyle factors, smoking status, alcohol use, physical activity, psychological factors, diet and socioeconomic status. The latest follow-up was carried out in 2001 (N = 2283, ages 24-39 y). In ddition to the usual protocol, this 21-y follow-up study included ultrasound measurements of carotid artery intima-media hickness (IMT) and carotid artery elasticity.

RESULTS

In this cohort, BMI measured in youth is significantly associated with BMI measured in adulthood. The correlation coefficient for 21-y tracking between childhood and adulthood BMI is r = 0.45 (P<0.0001). In multivariate analysis, childhood LDL-cholesterol, systolic blood pressure, BMI and smoking were all significantly associated with adult IMT. The effects of hildhood LDL-cholesterol and systolic blood pressure remained independently associated with carotid IMT when adjusted for the current risk factor values (P<0.01 for both). However, when adulthood BMI was entered into the model, the effect of childhood BMI became nonsignificant. The age- and sex-adjusted multivariate correlates of carotid artery elasticity included childhood skinfold thickness (sum of biceps, triceps and subscabular) and childhood systolic blood pressure. Childhood systolic lood pressure remained borderline significantly (P= 0.08) associated with carotid elasticity when the effect of current blood pressure was taken into account. However, the effect of childhood skinfold thickness on carotid artery elasticity became nonsignificant (P= 0.16) when adjusted with adult BMI.

CONCLUSIONS

The data from the Cardiovascular Risk in Young Finns Study suggest that obesity indices measured in youth are significantly associated with increased carotid artery IMT and decreased elasticity in adulthood. These relations are, at least, partly explained by significant tracking of obesity from youth to adulthood. These findings emphasize the importance of maintaining ideal weight from youth to adulthood in cardiovascular risk reduction.

The prevalence of the metabolic syndrome in Greece: the MetS-Greece Multicentre Study

BACKGROUND

The Third Report (ATP III) of the National Cholesterol Education Program Expert Panel (NCEP) highlighted the importance of identifying and treating patients with the metabolic syndrome (MetS) to prevent cardiovascular disease (CVD) and progression to diabetes mellitus. Limited information is available about the prevalence of MetS, as defined by the NCEP ATP III, in Europe, especially in Greece.

OBJECTIVE

To estimate the prevalence of the MetS in Greece, The MetS-Greece Study.

DESIGN AND PARTICIPANTS

A cross-sectional analysis of a representative sample of Greek adults (4153 participants older than 18 years). One group consisting of military personnel (n = 300) and another one from a Greek Muslim Community (n = 300) were used for comparison. In all, 4753 subjects were included in the final analysis.

RESULTS

All subjects from the general population were Caucasian men (49%) and women (51%), living in urban (n = 2243, 54%), semi-urban (n = 1038, 25%) and rural (n = 872, 21%) areas. The age-standardized prevalence of the MetS was 23.6%[95% confidence interval (CI): 22.4-25.1%]. This was similar in men (24.2%, 95% CI: 22.3-25.2%) and women (22.8%, 95% CI: 21.4-25.0%) (p = 0.3). The prevalence increased with age in both sexes, 4.8% among participants aged 19-29 years and 43% for participants over 70 years old (p for trend < 0.0001). There was a 14.7-fold increase in odds ratio for having MetS in the age group > 70 years old compared with that of 19-29 years old (p < 0.0001) Most of those with MetS had three components of the syndrome (61%), 29% had four and 10% had all five components. Abdominal obesity (82%) and arterial hypertension (78%) were the most common abnormalities in both sexes. The Greek Muslim Community, on a high-saturated fat diet, had the highest prevalence of the MetS (35.2%, 95% CI: 30.4-40.3%), and the military group, with a high physical activity level and a diet 'close' to Mediterranean, had the lowest (9.4%, 95% CI: 6.2-13.1%). According to the 2001 Census, about 2.3 million Greeks may have the MetS.

CONCLUSIONS

These results show that the MetS is highly prevalent in the Greek adult population. This may have major implications for the incidence of CVD. Promoting healthy diets, low caloric intake and physical activity must be urgently undertaken.

Obesity rather than severity of sleep-disordered breathing as the major determinant of insulin resistance and altered lipidemia in snoring children

OBJECTIVE

Sleep-disordered breathing (SDB) is associated with insulin resistance and dyslipidemia in adults and in obese children. However, the prevalence of such metabolic abnormalities among snoring children is unknown. This study was done to prospectively assess the relative contribution of SDB and obesity to metabolic disturbances in a large cohort of snoring children.

METHODS

Measurements of fasting serum glucose, insulin, and lipids were obtained after polysomnographic evaluation in 116 snoring children and in 19 control subjects. Insulin resistance was assessed using the insulin/glucose ratio (I/G ratio) and homeostasis model assessment (HOMA).

RESULTS

A total of 135 children (79 boys; mean age: 8.9 +/- 3.5 years) were studied. Sixty-four children had moderate to severe SDB (AHI = 5 per hour of total sleep time [TST]), 52 had mild SDB (AHI = 1 but <5 per hour of TST), and 19 were control subjects (AHI <1 per hour of TST). Seventy of these children were obese. No significant correlations were found between AHI, lowest arterial oxygen saturation, or arousal index and serum insulin, serum glucose, I/G ratio, HOMA, or serum lipids for either the whole group or the obese children only. However, significant positive correlations were found between I/G ratio and relative BMI (relBMI; r = 0.58), HOMA and relBMI (r = 0.52), triglycerides and relBMI (r = 0.30), and high-density lipoprotein and relBMI (r = 0.50). No significant differences were found in relBMI, I/G ratio, and lipid levels between boys and girls.

CONCLUSIONS

Among children with suspected SDB, insulin resistance and dyslipidemia seem to be determined primarily by the degree of body adiposity rather than by the severity of SDB.

Prevalence and risk factors associated with the metabolic syndrome and dyslipidemia in White, Black, Amerindian and Mixed Hispanics in Zulia State, Venezuela

Studies have highlighted the association between insulin resistance (IR) and several cardiovascular (CV) risk factors, including hypertension (HTN), obesity, dyslipidemia (i.e. high triglyceride and low HDL-cholesterol) and glucose intolerance, in a cluster known as the metabolic syndrome (MS). There are few data on the frequency of the MS and dyslipidemia in developing countries, and none in South America. To estimate the prevalence of the MS and its components in Zulia State, Venezuela, and to establish associated demographic and clinical factors, we evaluated 3108 Hispanic men and women aged 20 years or older from a cross-sectional survey of a random representative sample from each health district in Zulia State, Venezuela (1999-2001). Prevalence of the MS and dyslipidemia was defined according to the National Cholesterol Education Program (NCEP)/Adult Treatment Panel III (ATP III) criteria. The age-adjusted prevalence of MS and dyslipidemia was 31.2% and 24.1%, respectively, with higher rates in men than in women. Prevalence rates increased with age and with the degree of obesity. MS prevalence was lower in Amerindian (17.%) compared to Black (27.2%), White (33.3%) and Mixed (37.4%) men, but no differences were found among women. Overall, low HDL-cholesterol (65.3%), abdominal obesity (42.9%) and HTN (38.1%) were the most frequent MS components. After adjusting for age, sex and race groups, family history of diabetes, obesity and HTN were associated with the MS. Sedentary lifestyle also increased the risk of MS, event after adjusting for the same covariates, obesity and the degree of IR. These results suggest that MS is found in approximately one-third of the Venezuelan adult population in Zulia State, with higher prevalence in men related to the presence of dyslipidemia. Lifestyle interventions in MS subjects are needed in Venezuela to halt the burden of CV disease and diabetes.

Risk factor clusters for metabolic syndrome in coronary heart disease: state of the science

Metabolic syndrome, defined as a cluster of obesity, hypertension, dyslipidemia, and insulin resistance/glucose intolerance, has been identified as a major risk factor for coronary heart disease in women. Nurses should increase their awareness of metabolic syndrome to help identify and treat the current estimated 47 million US residents who have metabolic syndrome.

Intrauterine exposure to diabetes is a determinant of hemoglobin A(1)c and systolic blood pressure in pima Indian children

CONTEXT/OBJECTIVE

Given the increasing rates of both childhood obesity and type 2 diabetes (T2DM), we investigated whether maternal diabetes status during pregnancy is a determinant of risk factors associated with T2DM or cardiovascular disease in offspring during childhood.

DESIGN/PARTICIPANTS

Forty-two Pima Indians, aged 7-11 yr, were identified retrospectively from maternal oral glucose tolerance tests as offspring of a diabetic pregnancy (22 ODM, eight males, 14 females) or offspring born before the mother developed diabetes (20 PRE, 12 males, eight females). SETTING/MAIN OUTCOME MEASURES: Weight, height, body mass index, percent body fat, blood pressure, and fasting concentrations of glucose, insulin, hemoglobin A1c (HbA1c), total cholesterol, triglycerides, and high-density lipoprotein-cholesterol were measured while staying in an in-patient clinical research unit and compared in cross-sectional analyses.

RESULTS

After adjustment for age and gender, ODM had significantly higher concentrations of HbA1c (ODM = 5.7 +/- 0.4, PRE = 5.0 +/- 0.4%, P = 0.002), higher systolic (SBP) blood pressure (ODM = 118 +/- 13, PRE = 107 +/- 10 mm Hg; P = 0.02), and lower concentrations of high-density lipoprotein (ODM = 41 +/- 9, PRE = 48 +/- 6 mg/dl, P = 0.03) than PRE. Maternal diabetes status during pregnancy persisted as a significant determinant of SBP (beta = 7.50, P = 0.03) and HbA1c (beta = 0.43, P = 0.002), independent of age, gender, and percent body fat.

CONCLUSION

Intrauterine exposure to diabetes is a significant determinant of higher SBP and HbA1c during childhood, independent of adiposity and a genetic predisposition to T2DM. These data suggest that in utero exposure to diabetes confers an additional independent risk for the development of T2DM and/or cardiovascular disease later in life.

Factor Analysis of Clustered Cardiovascular Risks in Adolescence

Background— Clustering of cardiovascular (CV) risks begins in childhood, yet studies of the factor structure underlying this clustering have focused on adults. The increasing rates of obesity and type 2 diabetes and the growing importance of metabolic syndrome among adolescents make assessment of CV risk clustering even more urgent in this age group.

Methods and Results— Exploratory factor analysis (principal components analysis) was performed with data from 1578 healthy seventh to 12th graders from the Princeton School District Study, a school-based study in Cincinnati, Ohio. Measured CV risks included cholesterol, triglycerides, fasting insulin and glucose, body mass index (BMI), waist circumference, fibrinogen, and blood pressure. Factor analysis yielded 4 uncorrelated factors (adiposity [BMI, waist, fibrinogen, insulin], cholesterol [LDL and total cholesterol], carbohydrate-metabolic [glucose, insulin, HDL cholesterol, triglycerides], and blood pressure [systolic and diastolic blood pressure]). These factors explained approximately 67% of the total variance. A summary cumulative risk scale was derived from factor scores, and high risk was defined as scoring in the top 5%. Although insulin loaded onto both the adiposity and carbohydrate-metabolic factors, obesity was a much stronger correlate of high cumulative risk (odds ratio=19.2; 95% CI, 7.6 to 48.5) than hyperinsulinemia (odds ratio=3.5; 95% CI, 1.8 to 6.8). A sizable proportion (18.5%; n=12) of those who were at high cumulative risk were not at high risk for any of the individual factors.

Conclusions— The patterning of CV risk clustering seen among adults is present in healthy adolescents. Among youth, obesity is the predominant correlate of cumulative risk.

The influence of lifestyle on cardiovascular risk factors. Analysis using a neural network

The cardiovascular pathologies are the most common causes of death in the elderly patient. To single out the main risk factors in order to effectively prevent the onset of the disease, the authors experimented a special computerized tool, the neural network, that works out a mathematical relation that can obtain certain data (defined as output) as a function of other data (defined as input). Data were processed from a sample of 276 subjects of both sexes aged 26-69 years old. The output data were: high/low cholesterolemia, HDL cholesterol, triglyceridemia with respect to an established cut-off; the input data were: sex, age, build, weight, married/single, number of children, number of cigarettes smoked/day, amount of wine and number of cups of coffee. We conclude that: (i) a relationship exists, deduced from a neural network, between a set of input variables and a dichotomous output variable; (ii) this relationship can be expressed as a mathematical function; (iii) a neural network, having learned the data on a sufficiently large population, can provide valid predictive data for a single individual with a high probability (up to 93.33%) that the response it gives is correct. In this study, such a result is found for two of the three cardiovascular risk indicators considered (cholesterol and triglycerides); (iv) the repetition of the neural network analysis of the cases in question after a "pruning" operation provided a somewhat less good performance; (v) a statistical analysis conducted on those same cases has confirmed the existence of a strong relationship between the input and the output variables. Therefore the neural network is a valid instrument for providing predictive in a single subject on cardiovascular pathology risks.

Correlation of the dysmetabolic risk factors with different anthropometric measurements

Metabolic syndrome is a common disorder in Taiwan. For this study 431 subjects were randomly selected from visitors to the Department of Health Management. Blood pressure, blood glucose, lipid, uric acid levels and anthropometric measurements with immunoreactive insulin (IRI) and leptin levels were all correlated. We randomly selected 431 subjects who visited the Department of Health Management. Whole body three-dimensional (3-D) laser scanner scans were employed for the anthropometric measurements. The metabolic index (MI) was designed using anthropometric parameters. Of the 431 subjects, 50% had displayed a body mass index (BMI) equal to or exceeding 25 kg/m2. Pearson correlation coefficient and multiple regression analysis revealed that MI constituted another index for correlating metabolic parameters by comparing MI with BMI and waist circumference to hip circumference ratio (WHR). Most data related to metabolic syndrome showed statistically significant differences between high and low IRI groups, comprising uric acid, total cholesterol, fasting plasma glucose, triglyceride, LDL, Chol/HDL ratio, and LDL/HDL ratio. Both IRI and leptin revealed statistical association with BMI, WHR, waist cross section area to hip cross section area ratio (WHAR), and MI in the study. Hypercholesterolemia appeared in 14.6% of the subjects. Elevated low-density lipoprotein (> or = 130 mg/dL) affected 36.9% of the subjects. In conclusion, MI calculated from 3-D body scanner correlated with many important metabolic risk factors and associated with clinical disorders like DM, hyperlipidemia, hyperuricemia and hypertension.

Social inequalities in biomarkers of cardiovascular risk in adolescence

OBJECTIVE

Cardiovascular disease, which begins early in life but often is not manifest until adulthood, is the nation's leading cause of mortality. Social inequalities in cardiovascular disease are pervasive, yet the process by which they accrue is poorly understood. The objective of this study was to explore the associations between socioeconomic status, a range of biomarkers reflective of cardiovascular risks, and a cumulative physiological risk score among adolescents.

METHODS

Non-Hispanic black and white high school students (N = 758) in a suburban Midwestern public school district had a physical examination to measure height, weight, and waist circumference and a fasting morning blood sample drawn to assess cortisol, insulin, glucose, glycosylated hemoglobin, fibrinogen, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, and triglycerides. A cumulative risk score was created from these physiological measures and waist circumference. Information on parent education and household income was obtained from a parent in a separate survey. Generalized estimating equation models were used to assess the association of parent education to the risks and the cumulative risk score adjusting for age, gender, and race.

RESULTS

Lower parent education was associated with higher insulin, higher glucose, greater insulin resistance, higher LDL cholesterol, lower HDL cholesterol, higher waist circumference, and higher body mass index (p <.05 for all), but not cortisol, fibrinogen, glycosylated hemoglobin, or triglycerides in adjusted analyses. Cumulative risk scores ranged from 0 to 7 and were highly skewed; the median risk score was 1. A total of 7.4% had risk scores of 4 or more. Lower parent education was also associated with higher cumulative risk score (p <.001) and this association was maintained after adjustment for body mass index. Risk scores were highest, on average, among those with insulin levels greater than 1 standard deviation above the mean (mean risk score = 3.2, standard error = 0.18, median = 3).

CONCLUSION

Lower parent education is associated with multiple metabolic risks and cumulative risk in adolescents, suggesting that there is a strong intergenerational transfer of education's influence on cardiovascular health. Our data imply that regulation of insulin may be a key factor underlying the influence of lower parent education on cardiovascular health early in the life course.

The metabolic syndrome in children and adolescents

The metabolic syndrome is a constellation of metabolic abnormalities that result in an increased risk for type 2 diabetes mellitus and cardiovascular disease in adults. It emerges when a person's predisposition for insulin resistance is worsened by increasing central obesity and is largely confined to the overweight population. The United States National Cholesterol Education Program's Adult Treatment Panel III report proposed a set of criteria for the clinical diagnosis of metabolic syndrome in the adult population. A uniform definition for the paediatric population is lacking. Despite this, several studies have demonstrated that features of the syndrome develop in childhood and that the syndrome is present in up to 30% of obese children (body mass index at or above the 95th percentile). Ninety per cent of obese children meet at least one of the five criteria. The degree of abnormality is related to the body mass index, waist circumference and fasting insulin levels. There appears to be a genetic predisposition to the development of the syndrome and certain ethnic groups are at increased risk. The intrauterine environment also appears to play a role. Insulin resistance should be targeted for treatment through exercise and dietary intervention. The role of pharmacotherapeutic agents remains unclear. A uniform definition of the metabolic syndrome for paediatric patients needs to be created. Early intervention should be instituted because many of the features of the syndrome track from childhood into adulthood.

Application of three-dimensional body scanner: observation of prevalence of metabolic syndrome

BACKGROUND AND AIMS

This retrospective cross-sectional study correlates blood pressure, blood glucose, lipid and uric acid levels with anthropometric measurements.

METHODS

A total of 3975 visitors to the Department of Health Management were randomly selected to participate in this cross-sectional study. Whole body three-dimensional (3-D) laser scans were used to obtain anthropometric measurements. A health index (HI) was also designed based on anthropometric parameters. Subjects were defined as having metabolic syndrome when three of the following criteria were met: obesity (BMI of at least 30 kg/m(2); or a WHR of over 0.9 for males and 0.85 for females); triglyceride of at least 150 mg/dl; high-density lipoprotein (HDL)-cholesterol below 35 mg/dl for males and 39 mg/dl for females; fasting sugar levels of at least 110 mg/dl and hypertension.

RESULTS

Of 3975 subjects, 341 (8.6%) met the criteria for diabetes mellitus (DM); of these, 32.8% were diagnosed with hypertension. This proportion exceeded 18% of the subjects had normal glucose levels. Of the 3975 subjects, 658 (16.6%) met the criteria for metabolic syndrome. Proportionally, more male subjects than female subjects were diagnosed with metabolic syndrome (18.5% vs 14.7%). Of these, central obesity, elevated triglyceride and low HDL-cholesterol were the main factors in men, while fasting glucose, hypertension and central obesity were the main factors in women. This investigation found that larger proportions of subjects with impaired glucose tolerance (41.1%) and DM (64.2%) than of subjects with normal glucose subjects, suffered from metabolic syndrome (9.5%).

CONCLUSIONS

3-D body scanning is useful in correlating pertinent factors with metabolic syndrome, these factors include central obesity, hyperglycemia, dyslipidemia, hyperuricemia and hypertension.

Overweight in children: definitions, measurements, confounding factors, and health consequences

The epidemic of childhood overweight continues to grow at staggering rates, increasing nearly four-fold between 1963 and 2000. Children that are overweight are more apt to be overweight adults and are more likely to suffer adverse health consequences associated with excess weight. Nurses have a unique presence in the healthcare environment to assess children for overweight, provide parent/child nutritional education, and conduct obesity-related research. This article provides an overview of the current body of literature surrounding the definition and measurement of overweight and the morbidity association with childhood overweight.

What is the relationship between exercise and metabolic abnormalities? A review of the metabolic syndrome

Prevention of the metabolic syndrome and treatment of its main characteristics are now considered of utmost importance in order to combat the epidemic of type 2 diabetes mellitus and to reduce the increased risk of cardiovascular disease and all-cause mortality. Insulin resistance/hyperinsulinaemia are consistently linked with a clustering of multiple clinical and subclinical metabolic risk factors. It is now widely recognised that obesity (especially abdominal fat accumulation), hyperglycaemia, dyslipidaemia and hypertension are common metabolic traits that, concurrently, constitute the distinctive insulin resistance or metabolic syndrome. Cross-sectional and prospective data provide an emerging picture of associations of both physical activity habits and cardiorespiratory fitness with the metabolic syndrome. The metabolic syndrome, is a disorder that requires aggressive multi-factorial intervention. Recent treatment guidelines have emphasised the clinical utility of diagnosis and an important treatment role for 'therapeutic lifestyle change', incorporating moderate physical activity. Several previous narrative reviews have considered exercise training as an effective treatment for insulin resistance and other components of the syndrome. However, the evidence cited has been less consistent for exercise training effects on several metabolic syndrome variables, unless combined with appropriate dietary modifications to achieve weight loss. Recently published randomised controlled trial data concerning the effects of exercise training on separate metabolic syndrome traits are evaluated within this review. Novel systematic review and meta-analysis evidence is presented indicating that supervised, long-term, moderate to moderately vigorous intensity exercise training, in the absence of therapeutic weight loss, improves the dyslipidaemic profile by raising high density lipoprotein-cholesterol and lowering triglycerides in overweight and obese adults with characteristics of the metabolic syndrome. Lifestyle interventions, including exercise and dietary-induced weight loss may improve insulin resistance and glucose tolerance in obesity states and are highly effective in preventing or delaying the onset of type 2 diabetes in individuals with impaired glucose regulation. Randomised controlled trial evidence also indicates that exercise training decreases blood pressure in overweight/obese individuals with high normal blood pressure and hypertension. These evidence-based findings continue to support recommendations that supervised or partially supervised exercise training is an important initial adjunctive step in the treatment of individuals with the metabolic syndrome. Exercise training should be considered an essential part of 'therapeutic lifestyle change' and may concurrently improve insulin resistance and the entire cluster of metabolic risk factors.

Physical activity and biological risk factors clustering in pediatric population

BACKGROUND

From a preventive point of view, it is especially important to investigate the life style risk factors connected to cardiovascular disease (CVD) biological risk factors clustering. The purposes of this study were (I) to determine in pediatric population the coexistence of biological cardiovascular disease risk factors (high blood pressure (HBP), percentage of high fat mass (%HFM), and high total cholesterol (HTC)) and (II) to study the relationship between low physical activity, a lifestyle risk factor, with those biological risk factors.

METHODS

This study comprised 1461 children (699 males and 762 females) aged between 8 and 15 years old. The following measurements were carried out: blood pressure, percentage of fat mass, total cholesterol (TC), and physical activity. The quartiles, adjusted for age and gender, were the criterion used to classify the subjects at risk. Odds ratios and confidence intervals at 95% were used to study HBP, HTC, and %HFM clustering in both genders. Multinomial logistic regression was used to investigate the relationship between clustering and physical activity index (PAI).

RESULTS

The findings of this study indicated that there is clustering for the biological risk factors, specially between HBP and %HFM for females. It can be observed that about half of the subjects had at least one biological risk factor.

CONCLUSIONS

The results of the present study suggest that children and adolescents with higher PAI have a lower number of biological risk factors for CVD.

Ethnicity and tracking blood pressure in children

There is growing evidence that hypertension, one of the major modifiable risk factors for cardiovascular disease (CVD), is established early in life. Given this, it is important to discover when hypertension first becomes apparent. Further, it is of particular importance to examine the ethnic differences in blood pressure (BP) in children, given the variation in rates of CVD morbidity and mortality among adults from different ethnic groups.

Cardiovascular risk factors in Mexican-American children at risk for type 2 diabetes mellitus (T2DM)

PURPOSE

To assess risk factors for type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) with the hypothesis that risk for T2DM in children would be associated with an increase in risk factors for CVD.

METHODS

Subjects from a group of Mexican-American school children (aged 10-12 years) identified to be at risk for T2DM, and their siblings, were selected for this study. There were 68 children with acanthosis nigricans (AN+), and 71 without AN (AN-). Both AN+ and AN- children were assessed for T2DM and CVD risk factors. Probands and siblings were evaluated by physical examination, family history, and fasting serum parameters: glucose, insulin, body mass index (BMI), serum lipoproteins, and oxidized lipids. Data were analyzed by descriptive, univariate, and multivariate procedures.

RESULTS

BMI, waist/hip ratio, systolic and diastolic blood pressure were all significantly higher (p <.002) in AN+, whereas Tanner stages were similar in both groups. Fasting serum glucose was in the normal range, whereas insulin was elevated in AN+ compared with AN- (30.0 +/- 1.9 microU/mL vs. 14.8 +/- 1.0 p <.0001). Insulin resistance as assessed by the homeostasis assessment model (HOMA-IR) was elevated in both groups, although higher among AN+ (p <.0001). High-density lipoprotein-cholesterol (HDL-C) was lower (6.2 mg/dL) in the AN+ group (p <.003). The lower HDL-C in AN+ was associated with elevated triglycerides and a higher serum total cholesterol TC/HDL-C ratio when contrasted with the AN- values (145.9 +/- 7.6 mg/dL vs. 97.1 +/- 0.07, p <.0001; 4.1 +/- 0.2 vs. 3.4 +/- 0.1, p <.0001, respectively). In addition to the high prevalence of overweight/obesity (BMI > 85th percentile) in this population (76.3%, 106/139), elevated insulin (59.7% >15 microU/mL), low HDL-C (27.3% <40 mg/dL), and elevated low-density lipoprotein cholesterol (LDL-C) (41.0% >100 mg/dL) were also detected.

CONCLUSIONS

The altered metabolic pattern observed in this group of Mexican-American children is characteristic of metabolic syndrome, a condition associated with obesity and increased risk for both T2DM and CVD in adults. This study points to the value of BMI and acanthosis nigricans as easily accessible markers for children and nuclear families at increased risk for developing T2DM and CVD.

Insulin resistance and cardiovascular disease risk factors in children of parents with the insulin resistance (metabolic) syndrome

OBJECTIVE

To evaluate whether children of parents with the insulin resistance syndrome (IRS) themselves have greater insulin resistance and unfavorable patterns of cardiovascular disease (CVD) risk factors.

RESEARCH DESIGN AND METHODS

This cross-sectional study included 220 white and 36 black children aged 11-15 years identified through a school-based blood pressure screening program, along with 378 of their parents. Measures of insulin resistance (glucose disposal per minute per kilogram of lean body mass in a euglycemic-hyperinsulinemic clamp [Mlbm] and fasting insulin), adiposity, and other CVD risk factors were compared in children with and without a parental history of IRS, defined according to the National Cholesterol Education Program Adult Treatment Panel III consensus definition.

RESULTS

Compared with children in whom neither parent had IRS, children who had at least one parent with the syndrome had statistically significantly lower mean Mlbm (12.1 vs. 13.6 mg.kg(-1).min(-1); P=0.04) and higher fasting insulin (geometric means 99 vs. 76 pmol/l; P=0.01) after adjustment for sex, race, age, and Tanner stage. Mean BMI, waist circumference, waist-to-hip ratio, triceps and subscapular skinfolds, and percentage of body fat were also significantly higher in children of an affected parent, but there were no significant differences in lipid or blood pressure levels between the two groups.

CONCLUSIONS

Insulin resistance and obesity may be the earliest manifestations of IRS in children with a parental history of the syndrome.

The metabolic syndrome in children and adolescents

The metabolic syndrome was recently defined by the Adult Treatment Panel III. Despite a lack of uniform definition of the syndrome in pediatrics, recent studies have shown that the syndrome develops during childhood and is highly prevalent among overweight children and adolescents. The hypothesized central role of insulin resistance and obesity as a common underlying feature of the metabolic syndrome also appears to be already manifested in childhood. In view of the current obesity epidemic in children and adolescents, there is a vital need to provide adequate guidelines for the definition of the metabolic syndrome in pediatrics and for the development of screening and treatment strategies. This article focuses on the above issues, as well as on the impact of the syndrome on two major disease outcomes, type 2 diabetes and cardiovascular disease.

The metabolic syndrome in overweight Hispanic youth and the role of insulin sensitivity

The prevalence of the metabolic syndrome is highest among Hispanic adults. However, studies exploring the metabolic syndrome in overweight Hispanic youth are lacking. Subjects were 126 overweight children (8-13 yr of age) with a family history for type 2 diabetes. The metabolic syndrome was defined as having at least three of the following: abdominal obesity, low high-density lipoprotein (HDL) cholesterol, hypertriglyceridemia, hypertension, and/or impaired glucose tolerance. Insulin sensitivity was determined by the frequently sampled iv glucose tolerance test and minimal modeling. The prevalence of abdominal obesity, low HDL cholesterol, hypertriglyceridemia, systolic and diastolic hypertension, and impaired glucose tolerance was 62, 67, 26, 22, 4, and 27%, respectively. The presence of zero, one, two, or three or more features of the metabolic syndrome was 9, 22, 38, and 30%, respectively. After controlling for body composition, insulin sensitivity was positively related to HDL cholesterol (P < 0.01) and negatively related to triglycerides (P < 0.001) and systolic (P < 0.01) and diastolic blood pressure (P < 0.05). Insulin sensitivity significantly decreased (P < 0.001) as the number of features of the metabolic syndrome increased. In conclusion, overweight Hispanic youth with a family history for type 2 diabetes are at increased risk for cardiovascular disease and type 2 diabetes, and this appears to be due to decreased insulin sensitivity. Improving insulin resistance may be crucial for the prevention of chronic disease in this at-risk population.

Short-term predictors of overweight in early adolescence

OBJECTIVE

To identify short-term predictors of risk for overweight in early adolescence in a sample of Caucasian origin subjects, in Cyprus.

SUBJECTS

A total of 357 subjects (178 males) with baseline age 11.5+/-0.4 y were re-evaluated after a mean of 1.6+/-0.5 y.

MEASUREMENTS

Body weight and height, calculated body mass index (BMI), and blood pressure at baseline and follow-up. Serum lipids were determined at baseline. Obesity and overweight were defined at baseline and follow-up, according to the International Obesity Task Force data set. Socioeconomic class was determined. Self-reported parental weight and height were used to calculate the parental BMI. BMI tracking and changes in BMI categories were calculated (with 95% confidence interval (CI)). The future risk of overweight in baseline normal weight subjects was predicted using logistic regression analyses, where only normal weight subjects at baseline were included.

RESULTS

More males remained in the overweight or obese category than females: 86.7% (95% CI: 73.2, 94.9) vs 71.8% (95% CI: 55.1, 85.0), respectively, P=0.03. The identified predictors for future overweight were paternal obesity, odds ratio (OR): 7.1 (95% CI: 1.3, 38.0), systolic blood pressure >95th percentile, OR: 8.9 (95% CI: 1.9, 41.7), high triglyceride levels, OR: 4.2 (95% CI: 1.0, 16.9) and low HDL-cholesterol levels, OR: 7.6 (95% CI: 1.7, 34.3).

CONCLUSIONS

Triglycerides and HDL-cholesterol levels have been proved predictors for overweight in early adolescence for the first time. The different sex pattern in BMI tracking observed, and also the different environmental influences on future overweight risk compared to other studies, indicate that local circumstances should be considered when implementing national intervention strategies for the prevention of obesity.

Impaired microvascular function in normal children: effects of adiposity and poor glucose handling

Clustering of cardiovascular risk factors is thought to occur early in life. The endothelium is an important regulator of microvascular function. We investigated the relationship between microvascular function and cardiovascular risk factors in 145 normal, healthy children aged 11-14 years. Skin microvascular responses, measured using laser Doppler imaging, to iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP), were negatively correlated with percentage body fat (r = -0.20, P < 0.05 and r = -0.18, P < 0.05, respectively). Subjects were stratified into quintiles based on 2-h, post-feeding glucose levels. Subjects in the upper glucose quintile (range 7.4-11.4 mmol l-1) showed significantly lower vasodilatation to both ACh (P < 0.005) and SNP (P < 0.02) than those in the lower quintile (range 3.9-4.9 mmol l-1). Waist-to-hip ratio and the fasting insulin resistance index were significantly greater in subjects in the upper quintile than those in the lower quintile (P < 0.001 and P < 0.05, respectively). Additionally, in subjects in the upper glucose quintile, fasting triglyceride correlated with fasting insulin (r = 0.59, P < 0.001) and with the fasting insulin resistance index (r = 0.49, P < 0.009), and plasma levels of cholesterol and 2-h glucose were also correlated (r = 0.40, P < 0.05). In a cross-section of normal children, microvascular function was negatively associated with adiposity. Additionally, in a subgroup of subjects, there was a clustering of high post-feeding glucose, impaired microvascular function, increased insulin resistance and higher central fat distribution. These findings suggest that risk factors for adult cardiovascular disease begin to cluster in normal children, which might have important consequences for development of atherosclerosis later in life.

Prevalence of metabolic syndrome in an urban population: Tehran Lipid and Glucose Study

The aim of the present investigation was to determine the prevalence of the metabolic syndrome among 103,68 of the adults (4,397 men and 5,971 women) aged 20 years and over, participating in the Tehran Lipid and Glucose Study. The metabolic syndrome was defined by the presence of three or more of the following components: abdominal obesity, hypertriglyceridemia, low HDL-C, high blood pressure, and high fasting glucose. The unadjusted prevalence of metabolic syndrome in the study population was 30.1% (CI 95%: 29.2-31.0) and age-standardized prevalence was 33.7% (CI 95%: 32.8-34.6). The prevalence increased with age in both sexes. The metabolic syndrome was more commonly seen in women than in men (42% vs. 24%, P<0.001). Low HDL-C was the most common metabolic abnormality in both sexes. Except for high FPG, all abnormalities were more common in women than in men (P<0.001). Most of those with metabolic syndrome had three components of the syndrome (58%), 33% had four, and 9% had five components. This report on the metabolic syndrome from Iran shows a high prevalence of this disorder. Efforts on promoting healthy diets, physical activity, and blood pressure control must be undertaken.

Application of laparoscopy for bariatric surgery in adolescents

An epidemic increase in adolescent obesity in the United States has resulted in significant obesity-related comorbidities, previously seen only in adults. Although bariatric surgery is an acceptable alternative for weight loss in severely obese adults, no conclusions have been made about the appropriateness of bariatric surgery for individuals younger than 18 years old. Nonetheless, bariatric surgery is increasingly being performed on adolescents with clinically severe obesity and experience suggests that it is effective and safe. Application of the principles of adolescent growth, development, and compliance is essential to avoid adverse physical, cognitive, and psychosocial outcomes following bariatric surgery. Bariatric surgery should be part of a multidisciplinary approach to the management of adolescents with clinically severe obesity and should be performed by specialists dedicated to pediatric care, in institutions capable of meeting the guidelines for surgical treatment outlined by the American Society of Bariatric Surgery.

Deficiency of adrenomedullin induces insulin resistance by increasing oxidative stress

Hypertension, insulin resistance, and obesity are common age-related metabolic disorders that are often associated with increased oxidative stress and the resultant vascular damage. Underlying mechanisms have been suggested, and age-related overproduction of oxidative stress is one possible candidate. Since we recently found a vasoactive peptide, adrenomedullin, to be an endogenous antioxidant that potently inhibits oxidative stress-induced vascular damage, in the current study we evaluated oxidative stress-induced changes in aged mice. Insulin sensitivities in young and aged adrenomedullin-deficient mice were measured by means of the hyperinsulinemic-euglycemic clamp method; insulin resistance was apparent in aged adrenomedullin-deficient mice with increased urinary excretion of 8-iso-prostaglandin F2alpha, a marker of oxidative stress, but not in young adrenomedullin-deficient mice. Concomitantly, only aged adrenomedullin-deficient mice not only showed increased production of muscular reactive oxygen species, as demonstrated by the electron spin resonance method, but also had significantly decreased insulin-stimulated glucose uptake into the soleus muscle associated with impairment of insulin signals such as insulin receptor substrate-1,2 and phosphatidylinositol-3 kinase activities. In turn, these abnormalities could be nearly reversed by either treatment with 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl, a membrane-permeable superoxide dismutase mimetic, or adrenomedullin supplementation. Evidence presented in this report suggests that age-related accumulation of oxidative stress is involved in blood pressure regulation and insulin resistance in aged adrenomedullin-deficient mice, and adrenomedullin is thus an endogenous substance counteracting oxidative stress-induced insulin resistance associated with aging.

Hostility predicts metabolic syndrome risk factors in children and adolescents

The authors tested in 134 African American and European American children whether hostility measured at study entry predicted the metabolic syndrome risk factors an average of 3 years later. Hostility was measured with the Cook-Medley Hostility Scale (W. W. Cook & D. M. Medley, 1954) and with ratings of Potential for Hostility from interview responses. Metabolic syndrome was based on having at least 2 of the following risk factors above the 75th percentile of scores for their age, race, and gender group: body mass index, insulin resistance index, ratio of triglycerides to high-density lipoprotein cholesterol, and mean arterial blood pressure. Children who exhibited high hostility scores at baseline were likely to exhibit the metabolic syndrome at the follow-up. The results highlight the potential importance of early prevention and intervention of behavioral risk factors for cardiovascular disease.

New atherosclerosis risk factors in obese, hypertensive and diabetic children and adolescents

In the last few years it has been proved that risk factors for atherosclerosis are present in children and adolescents, and that already at this early age they are connected with anatomic, atheromatous changes in vessels. These changes can not be fully explained as occurring in young people exhibiting traditional risk factors for the disease. The aim of the study was to evaluate levels of several new atherosclerosis risk factors (lipoprotein (a) (Lp(a)), apolipoprotein A-I (Apo A-I), apolipoprotein B (Apo B), homocysteine (Hcy), fibrinogen (FB), tissue plasminogen activator (t-PA) and tissue plasminogen activator inhibitor type 1 (PAI-1)) in children and adolescents with traditional risk factors (obesity, hypertension, diabetes).

MATERIALS AND METHODS

The study group consisted of 285 children and adolescents aged 14.3 years. Children were divided according to their main disease into groups: group A, children with obesity (n=49); group B, children with obesity and coexisting hypertension (n=56); group C, children with hypertension (n=58) and group D, children with diabetes (n=122). Control group consisted of 79 healthy children and adolescents aged 14.1 years. Lp(a), Apo A-I and Apo B levels were estimated by use of immunoturbidimetric methods; total Hcy, FB, t-PA and PAI-1 were estimated by use of immunoenzymatic methods.

RESULTS

Lp(a) level in the total study group was 30 mg/dl and was over twice higher than in control group, 14 mg/dl. Apo A-I level was significantly lower in group A (127.6 mg/dl) and in group B (125.8 mg/dl) versus 135.6 mg/dl in controls. The level of Apo B was significantly higher in total study group (86.2 mg/dl) and in groups A, B and D versus 73.5 mg/dl in controls. Hcy was higher in group B (8 micromol/l) and in group C (9.4 micromol/l) versus 6.2 micromol/l in the control group. The FB level was higher in the total study group (276.7 mg/dl) and in groups A (318.8 mg/dl) and B (322.6 mg/dl) versus 252.8 mg/dl in controls. Significantly higher t-PA level was found in groups A (9 ng/ml) and B (9.7 ng/ml) versus 7.3 ng/ml in controls, and PAI-1 level was significantly higher in the total study group (62.3 ng/ml) and in groups A (73.8 ng/ml), B (78 ng/ml) and C (73 ng/ml) versus 42.4 ng/ml in the control group. Correlation analysis showed significant relationship between body mass index (BMI) and Apo B, Hcy, FB, t-PA and PAI-1. Blood pressure values correlated positively with Hcy. Correlations were verified in multiple regression analysis models: FB and t-PA levels depended on BMI, and Hcy depended on systolic blood pressure.

CONCLUSIONS

(1) Young obese, hypertensive and diabetic patients present significant disturbances in lipid metabolism, regarding mainly total cholesterol, LDL, triglycerides, as well as Lp(a), Apo A-I and Apo B levels. Unfavourable lipid profile is characteristic mainly for children with obesity and accompanying hypertension. (2) Elevated Hcy levels are found in children with hypertension. (3) Elevated FB level and diminished fibrinolytic activity are characteristic of obese children.

Clustering of lifestyle risk factors in a general adult population

BACKGROUND

The objective of the study was to evaluate the degree of clustering of common lifestyle risk factors in a general adult population and to define subgroups with elevated clustering.

METHODS

Data on lifestyle risk factors (smoking, low vegetable and fruit consumption, excessive alcohol intake, and low physical activity), sociodemographics, and health perception were collected by questionnaire from 16,789 men and women aged 20 to 59.

RESULTS

About 20% of the subjects had at least three lifestyle risk factors. Prevalence of risk factors was higher among unemployed, low-educated subjects and those who had experienced health deterioration. All lifestyle risk factors showed significant clustering, except for low physical activity and excessive alcohol consumption. The strongest association was observed for alcohol and smoking (prevalence odds ratio (POR): 2.38; 95% confidence interval: 2.18-2.61). Clustering of smoking and alcohol consumption was strongest among the young subjects (POR: 3.78) and, although moderately, clustering of lifestyle risk factors was elevated in subjects who had experienced a deterioration in health.

CONCLUSIONS

These findings suggest that common lifestyle risk factors cluster among adult subjects. The tendency for risk factors to aggregate has important implications for health promotion. Information on high-risk groups will help in planning future preventive strategies.

Insulin resistance syndrome and left ventricular mass in healthy young people

BACKGROUND

Findings of atherosclerotic plaques in adolescents, in the context of current epidemics of obesity and type 2 diabetes in youth, demand investigation into early cardiovascular risk development. Left ventricular hypertrophy has been linked to hypertension, obesity, and insulin resistance.

METHODS

Insulin resistance syndrome characteristics (fasting glucose and insulin; systolic blood pressure; waist girth) were measured in 70 normotensive, normoglycemic young people (60% male, 62% black; included 13 twin pairs; age mean +/- SD, 19 +/- 2.6 years). Left ventricular mass indexed by height (2.7) (LVMI) was obtained via ultrasound. Twin pairs were clustered to satisfy the assumption for independent observations.

RESULTS

LVMI was regressed on insulin after controlling for race, gender, and systolic blood pressure. Insulin was a significant (P = 0.02) independent predictor of LVMI (R(2)change = 0.09, P < 0.01). Waist girth accounted for an additional 4% variance of LVMI (P = 0.05). A one-factor model comprising waist (factor loading = 0.83), insulin (0.59), glucose (0.42), and LVMI (0.46) showed good fit [chi2(2) = 0.41, P = 0.81; root-mean-square error of approximation = 0.0].

CONCLUSIONS

A subclinical metabolic syndrome is detectable early in life, before abnormal fasting glucose or high blood pressure appear. Evidence of excessive load on the heart is associated with the metabolic syndrome even after accounting for the effects of race, gender, and blood pressure. Cardiac structure seems as closely associated with this syndrome as fasting glucose level. Based on this evidence, we propose that increased left ventricular mass is a part of insulin resistance syndrome and adds to the need for preventive public health measures to improve health behaviors and cardiovascular risk status in US youth.

Comparison of three-dimensional anthropometric body surface scanning to waist-hip ratio and body mass index in correlation with metabolic risk factors

In this study, we used a three-dimensional (3D) body scanner to evaluate subjects with central obesity. These measurements were correlated with blood pressure, blood glucose, lipid, and uric acid levels. We randomly selected 1,204 subjects who visited the Department of Health Management at Chang Gung Medical Center in Linkou. The health index (HI) was calculated as HI = (body weight x 2 x waist profile area)/[body height(2) x (breast profile area + hip profile area)]. Among the 1,204 subjects, body mass index (BMI) equal to or greater than 30 kg/m(2) was found in 8.3% of the subjects. Pearson correlation coefficient studies revealed that HI was a better index for correlating metabolic parameters than BMI and waist-to-hips girth ratio. Of the 1,204 subjects, 9.5% (114) had diabetes mellitus, according to American Diabetes Association criteria. The percentages of men and women with total cholesterol greater than or equal to 245 mg/dL were almost the same (11.0% vs. 11.1%). Elevated low-density lipoprotein (> or =130 mg/dL) was found in 36.9% (444) of subjects. In conclusion, HI as determined by 3D scanning, is another method to predict these metabolic abnormalities. Further prospective long-term follow-up study is needed to determine the relationships of 3D body scanning data and HI to blood pressure, blood glucose, lipid, and uric acid levels.

Metabolic correlates with obstructive sleep apnea in obese subjects

OBJECTIVE

To examine links between obstructive sleep apnea (OSA), insulin resistance, and dyslipidemia.

STUDY DESIGN

Obese (body mass index [BMI] >95th percentile for age and gender) children who snored (n = 62, 46 males, age 10.89 [5-16 years] underwent polysomnography and metabolic studies.

RESULTS

Respiratory disturbance index (RDI) was 9.23 (0-95), with 23 children (39%) recommended for treatment. Fasting insulin levels were 154.6 pmol/L +/- 79.8 (52-486), and fasting glucose levels were high in 7 children (11%). Fasting insulin levels correlated with sleep variables, including log transformed RDI (log(10)RDI) (P =.01), desaturation events (P =.05), arousal index (P =.01), and sleep-time with oxygen saturation in arterial blood <90% (P =.03) (adjusted r (2) = 0.21, F = 3.9, P =.005), but not with age, or BMI Z score. Log(10)RDI correlated with fasting insulin (P =.001) and BMI Z score (P =.03) (adjusted r (2) = 0.12, F = 3.9, P =.005), but not age or other metabolic variables. The correlation between log(10)RDI and fasting insulin persisted in models combining sleep and metabolic variables: log(10)RDI, adjusted r (2) = 0.75, F = 35.2, P <.001, and for fasting insulin, adjusted r (2) = 0.42, F = 6.1, and P <.001.

CONCLUSIONS

The severity of OSA (log(10)RDI) correlated with fasting insulin levels, independent of BMI. Insulin levels may be further elevated as a consequence of OSA in obese children.

Emergence of obesity and cardiovascular risk for coronary artery disease: the Bogalusa Heart Study

The underlying determinants of cardiovascular risk are governed by both genetic and lifestyle factors. One of the major adverse outcomes of unhealthy lifestyles is obesity, the genesis of which begins in childhood. Obesity, an important risk factor for atherosclerotic cardiovascular disease, type 2 diabetes, and hypertension, persists (tracks) strongly from adolescent years to adulthood. Secular trends toward increased obesity in the past 25 years have occurred in children and adults alike. Of interest, baseline adiposity precedes hyperinsulinemia in all age groups, independently of race, sex, and baseline insulin levels. Adiposity is an independent predictor of the risk of developing the cluster of risk variables of the metabolic syndrome X, beginning in childhood. Exposure to a multiple risk factor burden over time enhances the development of coronary atherosclerosis and hypertensive cardiovascular disease. In fact, autopsy studies in youths have shown that the extent of fibrotic atherosclerotic plaques in coronary arteries, measured antemortem, increases markedly with the presence of syndrome X risk variables. Further, in overweight children, insulin levels are associated with left ventricular mass. In young people, overnutrition, coupled with physical inactivity, leads to weight gain. Since obesity, unhealthy dietary habits, and a sedentary lifestyle are interrelated and modifiable, prevention and intervention must begin in early life. (c)2001 CHF, Inc.

Predictability of childhood adiposity and insulin for developing insulin resistance syndrome (syndrome X) in young adulthood: the Bogalusa Heart Study

The occurrence of insulin resistance syndrome (syndrome X) is common in the general population. However, information is scant on the childhood predictors of syndrome X. This study examined the relative contribution of childhood adiposity and insulin to the adulthood risk of developing syndrome X in a biracial (black-white) community-based longitudinal cohort (n = 745; baseline age, 8-17 years; mean +/- SD follow-up period, 11.6 +/- 3.4 years). The four criterion risk variables considered were the highest quartile (specific for age, race, sex, and study year) of 1) BMI, 2) fasting insulin, 3) systolic or mean arterial blood pressure, and 4) total cholesterol to HDL cholesterol ratio or triglycerides to HDL cholesterol ratio. Clustering was defined as the combination of all four risk variables. In addition to the criterion risk variables, clustered adults had adverse levels of total cholesterol, triglycerides, LDL cholesterol, HDL cholesterol, diastolic blood pressure, and glucose compared with those who did not cluster (P < 0.001). Childhood variables, except glucose, showed adverse trends with increasing number of criterion risk variables present in adulthood (P for trend, 0.01-0.0001). The proportion of individuals who developed clustering as adults increased across childhood BMI (P for trend <0.0001) and insulin (P for trend <0.01) quartiles. The relationship to childhood BMI remained significant even after adjusting for childhood insulin. In contrast, corresponding association with childhood insulin disappeared after adjusting for childhood BMI. In a logistic regression model, childhood BMI and insulin were significant predictors of adulthood clustering, with BMI being the strongest and showing a curvilinear relationship. Using an insulin resistance index instead of insulin did not change the above findings. These results indicate that childhood obesity is a powerful predictor of development of syndrome X and underscore the importance of weight control early in life.

Insulin resistance syndrome in childhood: associations of the euglycemic insulin clamp and fasting insulin with fatness and other risk factors

OBJECTIVE

Our objective was to describe in children the relation of fatness and insulin resistance to the risk factors associated with the insulin resistance syndrome and to compare fasting insulin with the euglycemic insulin clamp as a measure of insulin resistance in children.

STUDY DESIGN

This was a random selection of participants after blood pressure screening of 12,043 students in the fifth through eighth grades. Euglycemic insulin clamp studies with an insulin infusion rate of 1 mU/kg/min and a variable infusion of 20% glucose to maintain euglycemia, that is, plasma glucose at 5.6 mmol/L. Insulin sensitivity (M(lbm)) is defined as the amount of glucose required to maintain euglycemia (milligrams of glucose infused per kilogram lean body mass per minute).

RESULTS

Body mass index was significantly correlated with fasting insulin and significantly inversely correlated with M(lbm). Fasting insulin was significantly correlated with systolic blood pressure in both sexes, all lipids, except high-density lipoprotein-cholesterol in males and triglycerides and high-density lipoprotein-cholesterol in females, but after adjustment was done for body mass index, it was significantly related only to triglycerides. M(lbm) was significantly correlated only with triglycerides and high-density lipoprotein-cholesterol, and this did not change after adjustment was done for body mass index. A clustering effect for the risk factors was seen in children in the lowest quartile of M(lbm) (highest degree of insulin resistance) compared with children in the highest quartile of M(lbm) (lowest degree of insulin resistance).

CONCLUSIONS

As defined by M(lbm), there is an early association of insulin resistance, independent of body fat, with the risk factors. There is a significant relation between fasting insulin, as an estimate of insulin resistance, and the risk factors, but this is significantly influenced by body fatness. The clustering of risk factors according to level of M(lbm) suggests that adult cardiovascular disease is more likely to develop in children with the greatest degree of insulin resistance.

Childhood and adolescent obesity. Prevalence and significance

The prevalence of children and adolescents with body mass index (BMI) of greater than 95th percentile has doubled in the last 2 decades (present prevalence is 10.9%) and there is a 50% increase in the prevalence of those with a BMI greater than 85th percentile (present prevalence is 22.0%) in the US. There are substantial risks for morbidity in obese children even before they reach adulthood. Further, if obesity in childhood persists into the adult years, the morbidity and mortality is greater than if the obesity developed in the adult. Screening using appropriate historical and physical data will reveal those children most in need of modification of weight gain.

Prevalence of plasma lipid abnormalities in Saudi children

BACKGROUND

Lipid levels in children vary in different populations. Due to a close association between high lipid levels and development of atherosclerosis, considerable interest has been directed to investigating lipid levels in children.

MATERIALS AND METHODS

We conducted this study on 2914 children with ages ranging from 1 year to <15 years, randomly selected during a national household screening program. Fasting blood samples were used for estimation of triglyceride and cholesterol levels.

RESULTS

The overall range for cholesterol was 2.0-5.7 mmol/L and for triglyceride the overall range was 0.1-1.7 mmol/L. The children were separated into 14 groups depending on age, and the cholesterol and triglyceride levels were calculated in each age group. Using published guidelines for estimating "borderline" and "high risk" for coronary artery disease from cholesterol and triglyceride levels, the prevalence of borderline and high-risk groups was calculated. 7.72% of the children fell in the borderline risk group and 1.55% in the high-risk group using cholesterol values, while using triglyceride values, 1.4% and 0.55% fell in the borderline and high-risk groups, respectively. The prevalence of abnormality varied in the different age groups.

CONCLUSION

The paper discusses the need for a lipid awareness program in Saudi children in an attempt to decrease the complications associated with dyslipidemias during adulthood.