Inter-relationships between the severity of metabolic syndrome, insulin and adiponectin and their relationship to future type 2 diabetes and cardiovascular disease.

BACKGROUND: The severity of the metabolic syndrome (MetS) is related to future incidence of type 2 diabetes (T2DM) and cardiovascular disease (CVD). However, the relationship between MetS severity and levels of fasting insulin and adiponectin-markers of insulin resistance-is unclear. METHODS: We used linear and logistic regression to analyze data from 711 participants of the Princeton Lipid Research Cohort with information regarding levels of insulin, adiponectin and MetS severity during 1998-2003 (mean age 39.5 years); 595 participants had MetS severity data from childhood (1973-1976, mean age 12.9 years) and 417 had updated disease status from 2010 to 2014 (mean age 50.9 years). RESULTS: Childhood MetS Z-scores were positively associated with adult insulin levels (P<0.001) and negatively associated with adiponectin levels (P=0.01). In individual analyses, higher insulin levels and MetS Z-score as adults were related to higher odds of incident diabetes and CVD over the next 11.2 years (all P<0.001), whereas lower adiponectin levels were only related to odds of future T2DM (P<0.0001). In a model including insulin, adiponectin and MetS Z-score, adiponectin was not linked to future disease; both insulin (P=0.027) and MetS Z-score (P=0.002) were related to risk of future T2DM, while only MetS Z-score was related to future CVD (P<0.001). CONCLUSIONS: The severity of MetS exhibits long-term links to levels of insulin and adiponectin, suggesting potential genetic and environmental influences on insulin resistance over time. As a long-term predictor of T2DM and CVD, the severity of MetS exhibited consistent independent correlations. This supports clinical utility in evaluating MetS severity as a predictor of risk for future disease.

Receptor Tyrosine Kinase Expression Profiles in Canine Cutaneous and Subcutaneous Mast Cell Tumors.

The receptor tyrosine kinase (RTK) KIT is a major focus of current research into canine mast cell tumors (MCTs). Little is known about the role of other RTKs, such as vascular endothelial growth factor receptors (VEGFRs) and platelet-derived growth factor receptors (PDGFRs). These RTKs are dysregulated in many human and animal cancers and are key regulators of tumor angiogenesis. The aims of this study were to assess the expression and activation (phosphorylation) status of KIT, VEGFR2, and PDGFR (α and ß) in canine MCTs and to examine associations with various clinical outcomes. c-KITmutational status and KIT cellular localization pattern were also evaluated for these tumors. Twenty-seven MCTs, consisting of 5 subcutaneous and 22 cutaneous tumors, from 25 dogs were evaluated. MCT biopsies, cultured mast cells, and skin from the surgical margin were analyzed through Western blotting. MCT biopsies were also used for KIT immunohistochemical labeling and polymerase chain reaction for c-KITmutational analysis. MCT had heterogeneous expression profiles for all 3 RTKs, which varied in intensity and activation status. Statistical analyses showed phosphorylated KIT, VEGFR2, and KIT cellular localization to be predictive of decreased survival time, disease-free interval, and increased metastatic rate. Expression of VEGFR2 and KIT diffuse cytoplasmic labeling were also significantly associated with increased rate of local recurrence. The results of the study show that phosphorylated KIT, KIT, VEGFR2, and PDGFRß, in addition to KIT localization, may be valuable prognostic determinants in MCTs and should be further studied to improve diagnostic and therapeutic modalities.

Healthy lifestyle factors associated with reduced cardiometabolic risk.

Minimal data are available regarding the cumulative effects of healthy lifestyle behaviours on cardiometabolic risk. The objective of the present study was to examine a combination of healthy lifestyle behaviours associated with cardiometabolic risk reduction. The analysis was based on a cross-sectional study of 1454 participants from the population-based Lipid Research Clinic's Princeton Follow-up Study. The healthy lifestyle factors included fruit and vegetable intake ≥ 5 servings/d, meat intake ≤ 2 servings/d, never smoking, consuming 2-6 alcoholic drinks/week, television (TV) viewing time ≤ 2 h/d and moderate to vigorous physical activity ≥ 4 h/week. The combination of healthy lifestyle behaviours was strongly and negatively associated with the presence of cardiometabolic risk, as well as with a composite cardiometabolic risk score after adjustment for race, age, generation and sex. With each additional healthy lifestyle factor, cardiometabolic risk decreased by 31 % (OR 0·69; 95 % CI 0·61, 0·78). A higher healthy lifestyle score was associated with a lower prevalence of cardiometabolic risk (P for trend < 0·001). Compared with individuals having 0-1 healthy lifestyle behaviours, those with 5 or 6 healthy lifestyle behaviours had a 70 % lower prevalence of cardiometabolic risk (OR 0·30; 95 % CI 0·13, 0·67). Healthy lifestyle behaviours including sufficient fruit and vegetable intake, less meat intake, less TV viewing time, abstinence from smoking, modest alcohol intake and regular exercise are associated with reduced cardiometabolic risk.

Comparison of oral prednisone and prednisone combined with metronidazole for induction therapy of canine inflammatory bowel disease: a randomized-controlled trial.

BACKGROUND: Although prednisone and metronidazole are commonly used to treat canine inflammatory bowel disease (IBD), no randomized-controlled trials have been performed. HYPOTHESIS: Combination drug therapy with prednisone and metronidazole will be more effective than prednisone alone for treatment of canine IBD. Reduction in disease severity will be accompanied by decreased canine IBD activity index (CIBDAI) scores and serum C-reactive protein (CRP) concentrations. ANIMALS: Fifty-four pet dogs diagnosed with IBD of varying severity. METHODS: Dogs were randomized to receive oral prednisone (1 mg/kg; n = 25) or prednisone and metronidazole (10 mg/kg; n = 29) twice daily for 21 days. Clinical (CIBDAI) scores and serum CRP were determined at diagnosis and after 21 days of drug therapy. The primary efficacy measure was remission at 21 days, defined as a 75% or greater reduction in baseline CIBDAI score. RESULTS: Differences between treatments in the rate of remission (both exceeding 80%) or the magnitude of its change over time were not observed. CRP concentrations in prednisone-treated dogs were increased because of many dogs having active disease. Both treatments reduced CRP in comparison with pretreatment concentrations. An interaction between CIBDAI and CRP was identified in 42 of 54 dogs (78%), whereas 8 of 54 dogs (15%) showed disagreement between these indices. CONCLUSIONS AND CLINICAL IMPORTANCE: Prednisone is as effective as combined treatment with prednisone and metronidazole for induction therapy of canine IBD. CRP may be normal or increased in dogs with IBD and may be useful in assessing the response of individual dogs to treatment along with changes in the CIBDAI.

Fluorescence in situ hybridization confirms clearance of visible Helicobacter spp. associated with gastritis in dogs and cats.

BACKGROUND: The results of studies examining the role of Helicobacter spp. in the pathogenesis of canine and feline gastritis are inconclusive. Furthermore, data evaluating the effectiveness of medical therapy for eradication of Helicobacter infection are limited. AIM: To detect Helicobacter spp. in mucosal biopsies of dogs and cats diagnosed with gastritis, with fluorescence in situ hybridization (FISH). ANIMALS: Three dogs and 2 cats with signs of chronic gastrointestinal disease. METHODS: Dogs and cats infected with Helicobacter spp. were treated with triple antimicrobial therapy and fed an elimination diet for 21 days. Helicobacter spp. status in endoscopic (3 dogs, 1 cat) or surgical biopsies (1 cat) of gastric mucosa was compared pre- and posttreatment in each animal by histology, FISH analysis, and polymerase chain reaction (PCR). RESULTS: Gastritis of varying severity with intraglandular spiral bacteria was observed in all animals. Pretreatment diagnostic tests confirmed the presence of mucosal Helicobacter spp. in all animals by FISH and histopathology and in 4/5 animals by PCR. Rapid resolution of vomiting episodes was observed in all animals. Gastric biopsies performed after triple therapy revealed clearance of visible Helicobacter spp. by histopathology and negative FISH analysis, as well as PCR in all animals. CONCLUSIONS AND CLINICAL IMPORTANCE: Application of FISH to routine biopsy specimens enabled rapid and specific identification of Helicobacter spp. within the gastric mucosa of dogs and cats. Although medical therapy was useful in resolution of clinical signs and clearance of visible Helicobacter spp. in gastric biopsies, gastric inflammation persisted.

The pediatric metabolic syndrome.

The metabolic syndrome is a frequent subject of attention, discussion, and debate in medical research, because of its linkages to the growing problem of obesity on the one hand and both diabetes mellitus and cardiovascular disease on the other. It is also the grounds for contention, as respected researchers disagree on its definition and even on its validity as a construct. This clustering of obesity, dyslipidemia, elevated blood pressure, impaired glucose metabolism, and acute phase reactants can be seen in children as well as in adults. There are at least five definitions of adult metabolic syndrome promulgated by different societies and organizations, and as many as 40 different definitions of the syndrome have been used in pediatric studies. In 2007, the International Diabetes Federation published a definition of pediatric metabolic syndrome; whether it unifies the field remains to be seen. In addition, long term cohort studies have furnished data showing that clusters of the factors used to identify metabolic syndrome do predict the presence of type 2 diabetes and cardiovascular disease defined as myocardial infarction, stroke, coronary artery bypass graft, and/or positive angiogram. In addition, longitudinal studies have demonstrated compromised vascular function in young adults with metabolic syndrome, variously defined, as children and adolescents. This review discusses the background and development of the concept of a metabolic syndrome, the inter-relationships among its constitutive elements, the debates surrounding the uses of the concept and possible treatment avenues.

Identification of human urinary mitoxantrone metabolites.

Two polar metabolites of mitoxantrone, a clinically active antitumor agent, have been isolated and purified from the urine of patients by sequential absorption on glass wool and C18-Sep-Pak cartridges followed by preparative high-performance liquid chromatography. Negative ion chemical ionization mass spectrometry indicated that the two metabolites are the di- and mono-carboxylic acids resulting from oxidation of the terminal hydroxyl groups of the side chain(s). Mass spectral comparison of the urinary metabolites with synthetic compounds confirmed the identification.

Serum glutathione in adolescent males predicts parental coronary heart disease.

BACKGROUND: Traditional risk factors account for only half of the morbidity and mortality from coronary heart disease (CHD). There is substantial evidence that oxidative injury plays a major role in the atherosclerotic process. Thus, antioxidants may protect against development of atherosclerosis. Glutathione, an intracellular tripeptide with antioxidant properties, may be protective. METHODS AND RESULTS: This case-control study compared total serum glutathione (tGSH) in 81 adolescent male offspring of parents with premature CHD (ie, before 56 years of age) and 78 control male offspring of parents without known or suspected CHD. Case offspring had significantly lower tGSH than control offspring. In multiple logistic regression with parental CHD status as the dependent variable, age entered as a covariate, and other CHD risk factors competing to enter the model as significant independent predictor variables, LDL cholesterol (odds ratio [OR], 2.15 [units=1.5 SD]; 95% CI, 1.21 to 3.82), tGSH (OR, 0.40; 95% CI, 0.22 to 0.71), HDL cholesterol (OR, 0.42; 95% CI, 0.22 to 0.78), and total serum homocysteine (OR, 2.6; 95% CI, 1.35 to 5.02) entered the model as significant predictors of parental CHD status. CONCLUSIONS: Low tGSH in adolescent boys is a significant independent predictor of parental CHD, in addition to elevated LDL cholesterol, low HDL cholesterol, and elevated total serum homocysteine concentrations.

Correlates of the hemodynamic determinants of blood pressure.

The purpose of this study was to investigate the association of sex, race, lean body mass, and fat mass with the hemodynamic determinants of blood pressure, including stroke volume, heart rate, and total peripheral vascular resistance. The study included 201 subjects aged 6 to 17 years, 105 of whom were male and 98 of whom were black. Lean body mass and fat mass were both significant (P < .05) independent determinants of stroke volume, cardiac output, and total peripheral vascular resistance. However, the direction of the effect of lean body mass was opposite for stroke volume and cardiac output compared with that of total peripheral vascular resistance. The direct relationship of lean body mass with systolic blood pressure (SBP) and diastolic blood pressure (DBP) (regression coefficients, 0.55 +/- 0.05 for SBP and 0.47 +/- 0.05 for DBP) indicates that the effect of lean body mass on cardiac output may predominate. Lean body mass explained substantially more of the variance of the hemodynamic variables than did fat mass. After control for the effects of body size, male subjects had higher heart rate and cardiac output, and female subjects had higher vascular resistance. White subjects had higher stroke volume and cardiac output, and black subjects had higher peripheral vascular resistance. This study demonstrates that lean body mass is a more important correlate of the hemodynamic determinants of blood pressure than is fat mass and that sex and race have significant independent relationships with the hemodynamic determinants of blood pressure in children and adolescents.

Longitudinal correlates of change in blood pressure in adolescent girls.

The objective of this study was to assess the longitudinal changes in blood pressure in black and white adolescent girls and evaluate potential determinants of changes in blood pressure, including sexual maturation and body size. A total of 1213 black and 1166 white girls, ages 9 or 10 years at study entry, were followed up through age 14 with annual measurements of height, weight, skinfold thickness, stage of sexual maturation, systolic and diastolic blood pressures, and other cardiovascular risk factors. Average blood pressures in black girls were generally 1 to 2 mm Hg higher than in white girls of similar age over the course of the study. Age, race, stage of sexual maturation, height, and body mass index (kg/m2) were all significant univariate predictors of systolic and diastolic blood pressures in longitudinal regression analyses. Black girls had a significantly smaller increase in blood pressure for a given increase in body mass index compared with white girls. The predicted increases in blood pressure per unit increase in body mass index (mm Hg per kg/m2) were as follows: systolic, 0.65+/-0.04 in whites and 0.52+/-0.04 in blacks (P<.001); diastolic fourth Korotkoff phase, 0.31+/-0.04 in whites and 0.15+/-0.03 in blacks (P<.001); and diastolic fifth Korotkoff phase, 0.31+/-0.05 in whites and 0.16+/-0.04 in blacks (P<.001). Understanding of the determinants of the racial differences in blood pressure could provide the rationale for future interventions to reduce the excess cardiovascular mortality in black compared with white women.

Piperacillin kinetics.

Piperacillin was administered to normal, healthy volunteers by an intravenous infusion over 30 min at dosage regimens of 12 gm daily (4 gm every 8 hr) and 24 gm daily (6 gm every 6 hr) for 5 consecutive days. Mean peak serum level after 12 gm daily was 244 +/- 24 (SE) microgram/ml and after 24 gm daily, 353 +/- 7 microgram/ml. After infusion the serum level declined monoexponentially in most subjects. On the 12-gm daily dosage mean values were 60 min for half-life (t1/2), 16 1 for volume of distribution, 188 ml/min for body clearance, and 139 ml/min for renal clearance. The same values on day 4 were 47 min, 12 1, 181 ml/min, and 125 ml/min; the volume of distribution was lower than on day 1. On the 24-gm daily dosage regimen, t1/2 was 60 min; volume of distribution, 16 1; body clearance, 183 ml/min; and renal clearance, 101 ml/min on day 1 compared to 68 min, 15 1, 148 ml/min, and 71 ml/min on day 4, the last 2 being significantly lower than on day 1. High renal clearance values were observed at low serum concentrations and vice versa, suggesting saturation of the tubular secretion process at high piperacillin concentrations in serum.

Parent-child nutrient intake interrelationships in school children ages 6 to 19: the Princeton School District Study.

Interrelationships between nutrient intakes (dietary cholesterol, total carbohydrate, saturated and polyunsaturated fat, and total calories) of parents and children were examined in 294 families (60 black, 234 white) which included at least one parent and one child in the Princeton School survey of parents and their children, ages 6 to 19. The nutrient data were collected by means of the standardized Lipid Research Clinics' collaborative 24-hr dietary recall; simple correlations and analysis of covariance were used to assess parent-child nutrient intake (per kg body weight) relationships. There were significant positive simple correlations between nutrient intake of parents and children for total carbohydrate (r = 0.28, P < 0.0001), saturated fat (r = 0.15, P < 0.01), polyunsaturated fat (r = 0.19, P < 0.001), and calories (r = 0.24, P < 0.0001); parents' intake of cholesterol did not correlate with that of their children (r = 0.004, P > 0.1). By analysis of covariance with adjustment for sex, race, age, and recall group, the parent-child association of cholesterol intake was significant (P = 0.001), and the remaining parent-child nutrient intake relationships were congruent with those observed by simple correlations. The proportion of variation of the children's nutrient intake accounted for by parental nutrient intake varied from a low of 23% for parent-child cholesterol intakes (all parents-all children) to a high of 97% for carbohydrate intake in black fathers over age 40 and their children. The multiple Rs2 for black parents-black children for nutrient intakes were higher than those for white parents-white children for carbohydrate, saturated fat, and calories. Close parent child nutrient interrelationships not only suggest that a considerable portion of lipid-lipoprotein variability may be nutritionally-environmentally determined, but may contribute to clustering of coronary heart disease risk factors in families.

Lipids and lipoproteins in 13--18-year-old Venezuelan and American school children. Within- and cross-cultural comparisons.

Plasma lipids, lipoproteins, and anthropometric measurements were assessed in 996 Venezuelan school children (ages 13--18 years) (441 in private, 555 in public schools, Merida, Venezuela) with cross-cultural comparisons to 419 13--18-year-old American school children from suburban Cincinnati, Ohio. Although there were no systematic differences in plasma cholesterol and triglyceride between public and private Venezuelan school children, low density lipoprotein cholesterol (LDL-C) levels were higher and high density lipoprotein cholesterol (HDL-C) levels lower in public than private school children. Within Venezuelan schools, and between sex, female children had consistently higher total plasma cholesterol, marginally higher HDL-C, and appreciably higher LDL-C than males. There were no consistent cross-sectional changes in lipids and lipoproteins in Venezuelan school children with age. Within sex, cross-cultural comparisons with Cincinnati school children revealed 2 major, consistent differences; Venezuelan children had higher fasting plasma triglyceride and lower HDL-C levels, not attributable to systematic differences in Quetelet index, laboratory methodology, subject selection, or sampling technique. Total plasma cholesterol and HDL-C were similar for Venezuelan and Cincinnati school children. Maintenance of comparable LDL-C but lower HDL-C levels by Venezuelan children into adulthood might, speculatively, be associated with augmented risk for coronary heart disease.

Screening elderly populations for cobalamin (vitamin B12) deficiency using the urinary methylmalonic acid assay by gas chromatography mass spectrometry.

PURPOSE: This study assesses the value of the urinary methylmalonic acid (MMA) assay by gas chromatography mass spectrometry as a screening procedure for detection of cobalamin (Cbl) deficiency and estimates the prevalence of undetected Cbl deficiency in elderly populations. SUBJECTS AND METHODS: A total of 809 elderly individuals over age 65 were screened using random spot urine specimens from 4 different sites: a health fair, retirement apartments, a hospital-based elderly assessment center, and a nursing home. Follow-up tests included serum total Cbl, serum MMA, and normalization of urinary and serum MMA levels with Cbl intramuscular (IM) therapy. RESULTS: The prevalence of elevated urinary MMA varied across population groups, from 3.0% in elderly visiting a health fair to 5.1% in elderly residing in retirement apartments. Follow-up on 35 of 36 subjects with elevated urinary MMA levels showed that 18 had low serum total Cbl (less than 180 pg/mL at Hospital 1 or less than 200 pg/mL at Hospital 2), 12 had low-normal Cbl (180 or 200 pg/mL to 350 pg/mL), and 5 had normal Cbl. Of the 12 subjects with low-normal Cbl on retesting, further assessment was performed in 7, and all 7 of these subjects had evidence of Cbl deficiency. Cbl IM therapy was initiated for 23 subjects; 16 were seen for follow-up and all had normal urinary MMA. CONCLUSION: The relatively high prevalence of undetected Cbl deficiency identified in the seniors warrants additional studies of elderly populations. The sensitivity, convenience, and noninvasive nature of the urinary MMA assay by gas chromatography mass spectrometry make it a practical screening test.

Weight modification efforts reported by black and white preadolescent girls: National Heart, Lung, and Blood Institute Growth and Health Study.

OBJECTIVE: This study tested four hypotheses: (1) a high percentage of 9- and 10-year-old girls are already trying to lose weight; (2) more white tha black girls are trying to lose weight; (3) more black than white girls are trying to gain weight; and (4) weight modification efforts of preadolescent girls are influenced by factors other than race, such as maternal criticism, body dissatisfaction, and socioeconomic status. DESIGN: Cross-sectional analysis of baseline data on 2379 girls 9 and 10 years of age, which consisted of 1213 black and 1166 white enrollees. RESULTS: Black girls were taller and heavier and showed earlier signs of puberty than white girls but were less dissatisfied with their weight, body shape, and body parts. Approximately 40% of 9- and 10-year-old girls reported that they were trying to lose weight. Of those girls classified in the fourth quartile of body mass index (BMI), approximately 75% were trying to lose weight. After adjusting for BMI, no significant black and white differences in the prevalence of those trying to lose weight were seen, but significantly more black than white girls were trying to gain weight. Multiple logistic regression identified a high BMI, the mother telling her she was too fat, and body dissatisfaction as the major factors associated with trying to lose weight. However, chronic dieting was only associated with a high BMI and the mother telling her she was too fat. An important predictor of girls who were trying to gain weight was being black, along with having a low BMI and the mother telling her she was too thin. CONCLUSIONS: Attempts at gaining weight are much more frequent among black preadolescent girls than their white counterparts. No racial difference was found between black and white girls in their efforts to lose weight or to practice chronic dieting. Because approximately 40% of 9- and 10-year-old girls are already trying to lose weight, pediatricians should capitalize on this concern by providing information on proper weight control techniques. Educational efforts should be directed to both the mother and the child, because weight control efforts of preadolescent girls are stimulated by their mothers' admonitions of being too fat or too thin. The high prevalence of dieting among the thinnest adolescent girls also needs to be addressed by pediatricians.

Lipids in schoolchildren 6 to 17 years of age: upper normal limits.

As part of a multiclinic U.S. National Heart, Lung, and Blood Institute study of lipid levels of Americans, the University of Cincinnati studied a total school district's population. Out of a total of 8,906 eligible students from all grades, 6 to 17 years of age, 7,337 participated (82%). After fasting for 12 hours or more, plasma cholesterol and triglyceride levels were ascertained in 6,775 children. For white and black boys and girls, normal lipid values are given by age in both fasting and casual (nonfasting) states. This study group closely resembled a normal pediatric practice population, so that the values established may be used as baseline data for the practicing pediatrician. Since sex, race, and age are dominant sources for variations, care must be taken in the interpretation of minor changes that occur over time in a child.

Interrelationships between nutrient intake and plasma lipids and lipoproteins in schoolchildren aged 6 to 19: the Princeton School District Study.

Relationships between nutrient intakes and plasma lipids and lipoproteins were studied in 1,669 schoolchildren, aged 6 to 19 years; 948 were selected by random recall and 721 because of elevated plasma cholesterol or triglyceride (hyperlipidemic recall). Nutrient intake data was collected by using a 24-hour dietary recall. Median dietary cholesterol intakes for 6 to 9-year-old boys and girls in the random recall group were 222 and 230 mg/day, with polyunsaturated/saturated fat ratios of 0.34 and 0.33. For boys and girls, aged 10 to 12 years, median dietary cholesterol intakes were 296 and 235 mg/day, for 13 to 15 year olds, 343 and 237, and for 16 to 19 year olds, 418 and 221 mg/day. The dietary polyunsaturated/saturated fat ratios did not change appreciably with age. Partial correlation coefficients describing relationships between lipids, lipoproteins, and nutrients after adjustment for age, sex, race, and Quetelet index (W/H2) were calculated for all children (random and hyperlipidemic recall) after excluding children having plasma cholesterol, triglycerides, and calories less than or equal to the first or greater than or equal to the 99th percentiles for the random recall children. Plasma cholesterol was inversely and triglyceride positively correlated with dietary sucrose. Plasma low density lipoprotein cholesterol was inversely and triglyceride positively correlated with the dietary polyunsaturated/saturated fat ratio, total carbohydrate, and sugar. Potential relationships between nutrients and lipids-lipoproteins were also examined in children having low (first to tenth percentile), intermediate (45th to 55th percentile), and high (90th to 99th percentile) nutrient intake, after covariance adjustment for age, race, sex, and Quetelet index. Total plasma cholesterol fell as sucrose intake increased. Triglyceride rose along with caloric intake, total carbohydrate intake, and sucrose intake, while high density lipoprotein cholesterol levels fell with increasing caloric and sucrose intake. As dietary polyunsaturate ingestion rose from low to intermediate to high, plasma low density lipoprotein cholesterol increased. Nutrient intake may play a small but significant role relative to lipids and lipoproteins in children and, as such, may have importance relative to pediatric precursors of atherosclerosis.

Indexing left ventricular mass to account for differences in body size in children and adolescents without cardiovascular disease.

Left ventricular (LV) mass has been established as an independent risk factor for cardiovascular disease morbidity and mortality. To account for differences in body size, a variety of factors have been proposed for indexing LV mass. Dual energy x-ray absorptiometry provides a measure of lean body mass which can be used as a comparison with other more clinically applicable methods of standardization. The study included 192 subjects (100 male, 103 white) aged 6 to 17 years. Lean body mass was determined by dual energy x-ray absorptiometry and LV mass was calculated from M-mode echocardiographic measurements. There were significant differences by gender (males 98.7 g, females 80.3g, p < 0.001), but not race, for unindexed LV mass. Indexing LV mass by lean body mass eliminated the difference by gender. Log-log regression analysis revealed that the optimal height exponent for indexing LV mass was height3 (95% confidence interval, 2.8 to 3.1). LV mass/height3 provided the most consistently high intraclass correlation with LV mass/lean body mass versus indexing with body surface area, height, height2, and height2.7 across the 4 race/gender groups. LV mass indexed by height3 eliminated differences in LV mass by gender (males 26.1 +/- 4.72 g/m3, females 25.5 +/- 4.8 g/m3, p = NS). The proposed method for indexing LV mass by height3 should be useful in the clinical setting. The 90th and 95th percentiles of LV mass/height3 provide cutpoints for determining the presence of LV hypertrophy in children and adolescents.

Race, socioeconomic status, and obesity in 9- to 10-year-old girls: the NHLBI Growth and Health Study.

The purpose of this investigation was to determine whether measures of socioeconomic status (SES) are inversely associated with obesity in 9- to 10-year-old black and white girls and their parents. Subjects were participants in the Growth and Health Study (NGHS) of the National Heart, Lung, and Blood Institute. Extensive SES, anthropometric, and dietary data were collected at baseline on 2379 NGHS participants. The prevalence of obesity was examined in the NGHS girls and parents in relation to SES and selected environmental factors. Less obesity was observed at higher levels of household income and parental education in white girls but not in black girls. Among the mothers of the NGHS participants who were seen, lower prevalence of obesity was observed with higher levels of income and education for white mothers, but no consistent patterns were seen in black mothers. Univariate logistic models indicated that the prevalence of obesity was significantly and inversely associated with parental income and education and number of parents in the household in white girls whereas caloric intake and TV viewing were significantly and positively associated with obesity. Among black girls, only TV viewing was significantly and positively associated with the prevalence of obesity. Multivariate logistic regression models revealed that lower parental educational attainment, one-parent household, and increased caloric intake were significantly associated with the prevalence of obesity in white girls; for black girls, only increased hours of TV viewing were significant in these models. It is concluded that socioeconomic status, as measured by education and income, was related to the prevalence of obesity in girls, with racial variation in these associations. A lower prevalence of obesity was seen at higher levels of socioeconomic status in white girls, whereas no clear relationship was detected in black girls. These findings raise new questions regarding the correlates of obesity in black girls.

Differential classification of blood pressure by fourth and fifth Korotkoff phases in school-aged girls. The National Heart, Lung, and Blood Institute Growth and Health Study.

The use of the onset of the fourth (K4) or fifth (K5) Korotkoff phase to determine diastolic blood pressure in children has been controversial; most recently, the Second Task Force recommended the use of K4 for children up to age 13 years and K5 for children age 13 and above. We performed a cross-sectional analysis of 1,155 nine-year old (53% white and 47% black) and 1,224 ten-year old girls (45% white and 55% black) in the National Heart, Lung, and Blood Institute Growth and Health Study (NGHS). The mean blood pressures for the first, fourth, and fifth Korotkoff phases were 100.1 (+/- 8.9) mm Hg, 66.6 (+/- 9.8) mm Hg, and 56.8 (+/- 11.8) mm Hg for nine-year-olds and 102.8 (+/- 9.0) mm Hg, 68.1 (+/- 10.1) mm Hg, and 58.1 (+/- 11.9) mm Hg for ten-year-olds. The mean difference between K4 and K5 was 9.9 (+/- 6.4) mm Hg. The correlation between K1 and K4 was 0.45, between K1 and K5 was 0.34, and between K4 and K5 was 0.84. Elevation of blood pressure was defined at or above the 95th percentile based on the NGHS distribution for K1, K4, or K5; the relative risk of having an elevated K1 was 10.1 if K4 was elevated and 5.9 if K5 was elevated. Of the 159 subjects potentially classified with elevated diastolic pressure, 95 subjects (60%) would be classified differently depending on whether K4 or K5 was used to define elevated diastolic blood pressure. The choice of the onset of the fourth or fifth Korotkoff phase for determining diastolic blood pressure in children may have important implications for which individuals are classified as having hypertension.