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

Cardiovascular Disease Risk Reduction and Body Mass Index

PURPOSE OF REVIEW

Anti-hypertensive and lipid lowering therapy addresses only half of the cardiovascular disease risk in patients with body mass index > 30 kg/m², i.e., obesity. We examine newer aspects of obesity pathobiology that underlie the partial effectiveness of anti-hypertensive lipid lowering therapy for the reduction of cardiovascular disease risk in obesity.

RECENT FINDINGS

Obesity-related insulin resistance, vascular endothelium dysfunction, increased sympathetic nervous system/renin-angiotensin-aldosterone system activity, and glomerulopathy lead to type 2 diabetes, coronary atherosclerosis, and chronic disease kidney disease that besides hypertension and dyslipidemia increase cardiovascular disease risk. Obesity increases cardiovascular disease risk through multiple pathways. Optimal reduction of cardiovascular disease risk in patients with obesity is likely to require therapy targeted at both obesity and obesity-associated conditions.

Arterial Stiffness: Determinants and Relationship to the Metabolic Syndrome

This study aimed to investigate independent determinants of arterial stiffness and evaluate the association of arterial stiffness with the presence of metabolic syndrome (MS). Demographic characteristics, hemodynamic parameters, and cardiovascular (CV) risk factors were assessed in Greek food industry employees with no history of diabetes or CV disease in order to isolate multiple correlates of arterial stiffness as assessed by pulse wave velocity (PWV). Subsequently, logistic regression analysis was performed using as end point the presence of MS, defined according to the National Cholesterol Education Program. Data from 424 participants (mean age 45.3 ∓15.5 years, 298 [70.3%] males, average PWV 8.5 ∓3.6 m/s) were analyzed. PWV was higher in men (8.8 ∓3.1 m/s) compared to women (7.7 ∓2.9 m/s, p<0.01). Age, systolic blood pressure, and heart rate were isolated as multivariate determinants of PWV (adjusted R2 0.511 [p<0.0001] in men and 0.538 [p<0.0001] in women). The overall prevalence of the MS was 14.6%, being similar in both genders. Four variables were shown to be independent predictors of the presence of MS: waist circumference >102 cm (men)/88 cm (women) (OR 8.6, [95% CI 2.8, 20.6], p<0.001), insulin resistance (homeostasis model assessment >4) (6.3, [2.1, 17.6], p<0.001), total cholesterol >240 mg/dL (5.5, [1.7, 12.4], p<0.01), PWV >9 m/s (4.1, [1.5, 9.9], p<0.01). High PWV, which was found to be mostly determined by advanced age, elevated systolic BP, and accelerated heart rate, appeared to exhibit a strong independent association with the presence of MS together with adiposity and insulin resistance. This index should be considered as a useful marker for CV risk stratification.

The metabolic syndrome: an emerging risk state for cardiovascular disease

The common clustering of glucose intolerance, insulin resistance, abdominal adiposity, elevated blood pressure, and low HDL cholesterol is referred to as metabolic syndrome. Individuals with this syndrome have an increased risk of developing cardiovascular disease (CVD). The World Health Organisation and the National Cholesterol Education Programme’s Adult Treatment Panel III (NCEP-ATP III) have outlined specific diagnostic criteria for the diagnosis of the metabolic syndrome to help in the Identification of this syndrome in clinical practice. While the WHO criteria were specifically developed for use in research, the NCEP criteria are useful in clinical diagnosis of the metabolic syndrome. The metabolic syndrome is amenable to lifestyle modifications such as increased physical activity, weight loss, and possibly intake of low-glycemic foods. Drug therapy may be used to treat individual components of the syndrome such as elevated blood pressure and dyslipidemia. To control elevated glucose levels (when there is failure of lifestyle modification), medications such as metformin, thiazolidinedione derivatives and alpha glucosidase inhibitors may be used.

Parental Influence on Models of Primary Prevention of Cardiovascular Disease in Children

BACKGROUND

Lifestyle behaviors such as overeating and physical inactivity contribute significantly to CVD, the leading cause of morbidity and mortality among adults globally. CVD risk factors that begin in children often track into adulthood. Parents are believed to influence the health behaviors of their children.

OBJECTIVE

To review the literature on parental influence on children's health beliefs and behaviors, particularly eating and exercise behaviors as indicators of CV health, school-based CVD risk reduction programs, and racial/ethnic, gender and socioeconomic considerations for models of primary prevention of CVD in children.

METHODS

Seventeen studies that included parents as either a source of information, change agent or participant in a CVD risk reduction intervention were identified searching the Medline, CINAHL and PsycINFO databases from 1980 through 2002.

RESULTS

Children's lifestyle health beliefs and behaviors are significantly influenced by positive parental modeling and involvement in exercise and healthy eating; parental influence on children's behavior lasts beyond adolescence; parents are effective teachers of health habits at home when prompted by health educators; and parental influences vary by ethnicity/race, socioeconomics and gender.

CONCLUSIONS

A broader base of knowledge that is socioculturally sensitive must be developed about what parents and children believe is healthy, how parents model beliefs and behaviors for their children, and how to build self-efficacy for positive health behaviors.

Mood and its association with metabolic health in adolescents: a longitudinal study, EarlyBird 65

BACKGROUND

Mood comprises two main traits - positive and negative affect, both associated with depression and anxiety. Studies in children have linked depression with obesity, but the association with metabolic health is unclear.

OBJECTIVE

To explore the relationship between mood and metabolic health in adolescents.

METHODS

We studied 208 healthy children (115 boys) enrolled in the longitudinal EarlyBird Diabetes Study, and reviewed at 7 and 16 yr. Participants completed the Positive Affect and Negative Affect Schedule - Child Form (PANAS-C) at 16yr to assess positive and negative affect, together representing mood. Measures at 7 and 16 yr: body mass index (BMI), fat (%; dual energy X-ray absorptiometry), physical activity (accelerometer), metabolic risk z-score comprising homeostasis model assessment-insulin resistance (HOMA-IR), triglycerides, total cholesterol/high density lipoprotein (HDL) ratio and blood pressure. Pubertal development was determined by age at peak height velocity.

RESULTS

Positive affect was higher in boys than girls, (50 vs. 46, p = 0.001), negative affect higher in girls than boys (26 vs. 22, p < 0.001). Those with lower mood were fatter (r = -0.24, p < 0.001), had higher HOMA-IR (r = -0.12, p = 0.05), higher cholesterol:HDL ratio (r = -0.14, p = 0.02), were less active (r = 0.20, p = 0.003) and had earlier pubertal development (r = 0.19, p = 0.004). Inverse associations between mood and metabolic risk z-score and change in metabolic risk z-score 7-16yr (β = -0.26, p = 0.006, and -0.40, p = 0.004, respectively) were independent of adiposity, physical activity and puberty and sex.

CONCLUSIONS

Low mood in healthy children is associated with poorer metabolic health independently of adiposity. These findings may have implications for the physical and mental health of contemporary youngsters, given their increasing obesity and cardiometabolic risk.

Obesity and the response to intensified diuretic treatment in decompensated heart failure: a DOSE trial substudy

BACKGROUND

Obesity could attenuate diuretic effectiveness in treatment of acute decompensated heart failure (HF).

METHODS AND RESULTS

The DOSE trial randomized 308 subjects with acute HF to low- versus high-intensification intravenous diuretic therapy. We tested for statistical interactions between obesity and dosing strategy across clinical end points. After 72 hours of treatment, obese subjects (body mass index >30 kg/m(2); n = 173) had greater volume loss than nonobese subjects (n = 119) but similar improvements in dyspnea and freedom from congestion. Both groups had greater fluid loss with high-intensification treatment. Obese subjects had a higher incidence of worsening renal function (WRF) at 72 hours with low-intensification treatment, compared with nonobese subjects. In contrast, nonobese and obese subjects had similar incidence of WRF with high-intensification treatment. There were no differences between obese and nonobese subjects in time to discharge and 60-day freedom from death, emergency department visit, or rehospitalization.

CONCLUSIONS

The incidence of WRF was greater in obese than in nonobese subjects with low-intensification treatment. However, the frequency of WRF was equivalent in obese and nonobese subjects with high-intensification treatment. Additional studies are needed to assess whether obese patients with acute HF benefit from an initial high-intensification treatment strategy.

The effect of breastfeeding on childhood overweight and obesity: a systematic review of the literature

BACKGROUND

Childhood obesity has reached epidemic proportions. There is increasing attention to the topic of prevention and continued debate as to whether breastfeeding (BF) is protective against childhood obesity. Previous systematic reviews on this topic were done in 2005 showing that BF was protective against childhood obesity but, because of confounding variables, the evidence was weak.

OBJECTIVE

To explore the current evidence of the effect of BF on childhood obesity and provide recommendations for the nurse practitioner (NP) as a primary care provider.

METHODS

A systematic review of the literature from 1/2005 to 3/2012 was done to assess the evidence on the relationship between BF and childhood obesity.

RESULTS

The majority of studies identified in this article showed a relationship between BF and obesity prevention, but because of confounding maternal, child, cultural, genetic, and environmental variables, the relationship remains unclear.

CONCLUSIONS

While it is possible that there are protective benefits of BF on childhood obesity, it is difficult to prove because of confounding variables. However, because of other benefits for the mother and child, BF should be encouraged. Whether obesity in childhood can be prevented by BF remains unclear. Further research controlling for confounding variables is needed to provide concrete evidence.

School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6 to 18

BACKGROUND

The World Health Organization (WHO) estimates that 1.9 million deaths worldwide are attributable to physical inactivity and at least 2.6 million deaths are a result of being overweight or obese. In addition, WHO estimates that physical inactivity causes 10% to 16% of cases each of breast cancer, colon, and rectal cancers as well as type 2 diabetes, and 22% of coronary heart disease and the burden of these and other chronic diseases has rapidly increased in recent decades.

OBJECTIVES

The purpose of this systematic review was to summarize the evidence of the effectiveness of school-based interventions in promoting physical activity and fitness in children and adolescents.

SEARCH METHODS

The search strategy included searching several databases to October 2011. In addition, reference lists of included articles and background papers were reviewed for potentially relevant studies, as well as references from relevant Cochrane reviews. Primary authors of included studies were contacted as needed for additional information.

SELECTION CRITERIA

To be included, the intervention had to be relevant to public health practice (focused on health promotion activities), not conducted by physicians, implemented, facilitated, or promoted by staff in local public health units, implemented in a school setting and aimed at increasing physical activity, included all school-attending children, and be implemented for a minimum of 12 weeks. In addition, the review was limited to randomized controlled trials and those that reported on outcomes for children and adolescents (aged 6 to 18 years). Primary outcomes included: rates of moderate to vigorous physical activity during the school day, time engaged in moderate to vigorous physical activity during the school day, and time spent watching television. Secondary outcomes related to physical health status measures including: systolic and diastolic blood pressure, blood cholesterol, body mass index (BMI), maximal oxygen uptake (VO2max), and pulse rate.

DATA COLLECTION AND ANALYSIS

Standardized tools were used by two independent reviewers to assess each study for relevance and for data extraction. In addition, each study was assessed for risk of bias as specified in the Cochrane Handbook for Systematic Reviews of Interventions. Where discrepancies existed, discussion occurred until consensus was reached. The results were summarized narratively due to wide variations in the populations, interventions evaluated, and outcomes measured.

MAIN RESULTS

In the original review, 13,841 records were identified and screened, 302 studies were assessed for eligibility, and 26 studies were included in the review. There was some evidence that school-based physical activity interventions had a positive impact on four of the nine outcome measures. Specifically positive effects were observed for duration of physical activity, television viewing, VO2 max, and blood cholesterol. Generally, school-based interventions had little effect on physical activity rates, systolic and diastolic blood pressure, BMI, and pulse rate. At a minimum, a combination of printed educational materials and changes to the school curriculum that promote physical activity resulted in positive effects.In this update, given the addition of three new inclusion criteria (randomized design, all school-attending children invited to participate, minimum 12-week intervention) 12 of the original 26 studies were excluded. In addition, studies published between July 2007 and October 2011 evaluating the effectiveness of school-based physical interventions were identified and if relevant included. In total an additional 2378 titles were screened of which 285 unique studies were deemed potentially relevant. Of those 30 met all relevance criteria and have been included in this update. This update includes 44 studies and represents complete data for 36,593 study participants. Duration of interventions ranged from 12 weeks to six years.Generally, the majority of studies included in this update, despite being randomized controlled trials, are, at a minimum, at moderate risk of bias. The results therefore must be interpreted with caution. Few changes in outcomes were observed in this update with the exception of blood cholesterol and physical activity rates. For example blood cholesterol was no longer positively impacted upon by school-based physical activity interventions. However, there was some evidence to suggest that school-based physical activity interventions led to an improvement in the proportion of children who engaged in moderate to vigorous physical activity during school hours (odds ratio (OR) 2.74, 95% confidence interval (CI), 2.01 to 3.75). Improvements in physical activity rates were not observed in the original review. Children and adolescents exposed to the intervention also spent more time engaged in moderate to vigorous physical activity (with results across studies ranging from five to 45 min more), spent less time watching television (results range from five to 60 min less per day), and had improved VO2max (results across studies ranged from 1.6 to 3.7 mL/kg per min). However, the overall conclusions of this update do not differ significantly from those reported in the original review.

AUTHORS' CONCLUSIONS

The evidence suggests the ongoing implementation of school-based physical activity interventions at this time, given the positive effects on behavior and one physical health status measure. However, given these studies are at a minimum of moderate risk of bias, and the magnitude of effect is generally small, these results should be interpreted cautiously. Additional research on the long-term impact of these interventions is needed.

Biological significance of a thyroid hormone-regulated secretome

The thyroid hormone, 3,3,5-triiodo-L-thyronine (T3), modulates several physiological processes, including cellular growth, differentiation, metabolism and proliferation, via interactions with thyroid hormone response elements (TREs) in the regulatory regions of target genes. Several intracellular and extracellular protein candidates are regulated by T3. Moreover, T3-regulated secreted proteins participate in physiological processes or cellular transformation. T3 has been employed as a marker in several disorders, such as cardiovascular disorder in chronic kidney disease, as well as diseases of the liver, immune system, endocrine hormone metabolism and coronary artery. Our group subsequently showed that T3 regulates several tumor-related secretory proteins, leading to cancer progression via alterations in extracellular matrix proteases and tumor-associated signaling pathways in hepatocellular carcinomas. Therefore, elucidation of T3/thyroid hormone receptor-regulated secretory proteins and their underlying mechanisms in cancers should facilitate the identification of novel therapeutic targets. This review provides a detailed summary on the known secretory proteins regulated by T3 and their physiological significance. This article is part of a Special Issue entitled: An Updated Secretome.

A shift from underweight to overweight and obesity in Asian children and adolescents with congenital heart disease

BACKGROUND

In Western countries, obesity is a common problem in children with congenital heart disease (CHD). However, this problem may have racial difference, and little is known about the shift of this trend as patients grow up. The present study sought to investigate the prevalence and trends of being underweight, overweight and obesity in an Asian CHD cohort using a 5-year citywide school survey database.

METHODS

Patient group consisted of 705 first grade elementary school students (children) and 219 first grade senior high school students (adolescents), while 18753 healthy children and 15014 healthy adolescents served as controls. Body mass index (BMI) percentile was calculated to define underweight (BMI < 15(th) percentile) and overweight (BMI 85(th) -95(th) percentile)/obesity (BMI ≥ 95(th) percentile).

RESULTS

In CHD children, the prevalence of underweight and overweight/obesity was 21.0% (control 16%, P < 0.001) and 14.5% (control 19.8%, P < 0.001), respectively. Children with moderate to severe CHD, especially cyanotic CHD, were more underweight and less overweight/obese than children with non-cyanotic CHD. The prevalence of underweight (23.3%) and overweight/obesity (26.5%) in CHD adolescents became close to that in controls. From childhood to adolescence, different shifts in BMI distribution were noted; controls became more underweight and overweight/obese for males and more underweight and less overweight/obese for females, while CHD patients became more overweight/obese for both genders, including cyanotic CHD.

CONCLUSIONS

In this Asian CHD cohort, we demonstrates a shift of BMI distribution from more underweight and less overweight/obese compared with healthy children, to a pattern similar to that in healthy adolescents.

Age variation and sexual dimorphism in the sixteen diagnostic clusters of risk factors for the metabolic syndrome

Objective

To document age- and sex-related differences in the 16 phenotypes of risk factors for the metabolic syndrome (MS) among adults in the Fels Longitudinal Study (FLS).

Methods

Data on risk factors for the MS were analyzed in 471 white men and 503 white women in the FLS. We used the Cochran-Armitage test to compare age- and sex-related differences in the prevalence of the 16 diagnostic clusters of positive risk factors.

Results

Of the 974 subjects, 238 were found to meet diagnostic criteria for 15 of a possible 16 phenotypes of the MS. The prevalence of the MS was four times greater in subjects older than 40 years than in subjects 20–40 years old. Older subjects had more risk factors exceeding criterion values than younger subjects. Among those who met three-to-five criteria for the MS, younger subjects were more likely to have dyslipidemia, less likely to have high blood pressure (HBP), and two times less likely to have impaired fasting plasma glucose (IFG) than subjects 40+ years old. Older men were more likely than older women to have HBP and IFG. . We found that if one of the five risk factors reaches a criterion value, the values for the other four risk factors move closer to their own diagnostic criterion values in apparent synchrony.

Conclusions

Subjects 40+ years old are four times likelier to have the MS than younger subjects, and older men are at higher risk than older women. The mean values for each of the five risk factors get progressively worse as the number of risk factors meeting diagnostic criteria increases. Therefore, when one factor is found to meet its diagnostic criterion, levels of the other four risk factors should be measured. The different phenotypic patterns that comprise the MS should prompt clinicians to target specific risk factors for prevention or treatment. Certain phenotypes were found more commonly in women and certain others more commonly in men. Similarly, certain phenotypes were found more commonly in older than in younger age groups. These age- and sex-specific phenotypes should help clinicians to identify subjects at highest risk for certain risk factors and to initiate specifically tailored preventive and therapeutic interventions. Our observations should also stimulate clinical investigators and epidemiologists to ascertain what factors determine the sex and age specificity of certain phenotypes of the MS.

Recommendations to improve physical activity among teenagers--a qualitative study with ethnic minority and European teenagers

BACKGROUND

To understand the key challenges and explore recommendations from teenagers to promote physical activity with a focus on ethnic minority children.

METHODS

Focus groups with teenagers aged 16-18 of Bangladeshi, Somali or Welsh descent attending a participating school in South Wales, UK. There were seventy four participants (18 Somali, 24 Bangladeshi and 32 Welsh children) divided into 12 focus groups.

RESULTS

The boys were more positive about the benefits of exercise than the girls and felt there were not enough facilities or enough opportunity for unsupervised activity. The girls felt there was a lack of support to exercise from their family. All the children felt that attitudes to activity for teenagers needed to change, so that there was more family and community support for girls to be active and for boys to have freedom to do activities they wanted without formal supervision. It was felt that older children from all ethnic backgrounds should be involved more in delivering activities and schools needs to provide more frequent and a wider range of activities.

CONCLUSIONS

This study takes a child-focused approach to explore how interventions should be designed to promote physical activity in youth. Interventions need to improve access to facilities but also counteract attitudes that teenagers should be studying or working and not 'hanging about' playing with friends. Thus, the value of activity for teenagers needs to be promoted not just among the teenagers but with their teachers, parents and members of the community.

High-sensitivity C reactive protein: associations with cardiovascular risk factors and tracking in female adolescents and young adults

Objective. We assessed adolescent anthropometry, lipids, insulin, glucose, and blood pressures to identify factors associated with high-sensitivity C-reactive protein (hsCRP) and its tracking in young adults. Methods. Ten-year prospective study of 589 schoolgirls, 321 black, 268 white. Results. HsCRP did not differ (P > .08) by race or oral contraceptive use. HsCRP tracked from age 16 to 25 (r = 0.77), 16 to 26 (r = 0.50), 24 to 26 (r = 0.66), and 25 to 26 (r = 0.71), all P ≤ .02. By stepwise regression, at age 16, waist circumference accounted for 44.8% of hsCRP variance; BMI accounted for 33.1%, 34.4%, and 31.1% at ages 24, 25, and 26, P < .0001 for all. Changes in cholesterol and BMI were associated with change in hsCRP from age 24-26 (partial R(2) = 12.3%  P < .0001, 6.6%  P = .0012). Changes in BMI and triglyceride (partial R(2) = 8.5%  P = .0001, 3.3%, P = .0045) were associated with change in hsCRP from age 25 to 26. Conclusions. HsCRP tracks from age 16 to 26, with BMI, waist circumference, and cholesterol as major determinants.

Adiponectin moderates the relationship between adiposity and leptin in adolescents regardless of gender or race

OBJECTIVES

To determine gender or race differences in associations between adiposity and leptin, and whether adiponectin moderates these relationships.

METHODS

Subjects were 441 adolescents, 14-18 years old (44% black, 56% white; 50% female, 50% male). Percent body fat (%BF) was measured with dual-energy X-ray absorptiometry. Leptin and adiponectin were measured using immunoassays.

RESULTS

Among the four groups (white boys, white girls, black boys and black girls), white girls had the highest adiponectin (p = 0.0017) and black girls had the highest leptin (p = 0.0164). Percent BF and leptin were positively correlated (p = 0.0164). The %BF-leptin relationship was stronger in boys than girls (p < 0.0001). Those with lower adiponectin had a stronger %BF-leptin relationship than those with high adiponectin in the entire sample (p = 0.0220). Statistical models were adjusted for age, race, gender and the interaction between race and gender.

CONCLUSION

Our data suggest a protective metabolic interaction for adiponectin and lend additional support for obesity prevention strategies in adolescents.

Adiposity, physical activity and blood lipid profile in 13-year-old adolescents

The main aim of this study was to determine the extent to which physical activity and adiposity are associated with blood cholesterol levels in male adolescents. Anthropometric and physical fitness values were measured in all children. Body mass index (BMI) and physical activity index (PAI) were used to split participants into active overweight (ACO) and non-active normal-weight (NAN) groups. The cutoffs for the ACO group were BMI > or = 22.6 kg/m2 and PAI > or = 3.5, respectively, whereas the corresponding cutoffs for the NAN groups were BMI < 20.0 kg/m2 and PAI < 2. A total of 65 children (29 in ACO group, 36 in NAN group) were selected according to the above criteria. ACO group showed significantly higher BMI and body fat as compared to their NAN counterparts (p < 0.05). Adolescents from ACO group attained superior scores for PAI and aerobic fitness (p < 0.05). Most blood lipid variables were significantly lower in ACO group as compared to NAN (p < 0.05) while HDL-cholesterol was higher in ACO group (p < 0.05). There was significant positive correlation between HDL-cholesterol and PAI in ACO group (r = 0.38; p < 0.05). The physical activity index explained the majority of variance in HDL-cholesterol for ACO group (beta = 0.513; p < 0.05). It seems that physical activity in adolescents is a more important factor in balancing blood lipid status than adiposity per se, particularly for HDL-cholesterol.

End-stage renal disease in young black males in a black-white population: longitudinal analysis of the Bogalusa Heart Study

Background

Risk factors in childhood create a life-long burden important in the development of cardiovascular (CV) disease in adulthood. Many risk factors for CV disease (e.g., hypertension) also increase the risk of renal disease. However, the importance of childhood risk factors on the development of chronic kidney disease and end-stage renal disease (ESRD) is not well characterized.

Methods

The current observations include data from Bogalusa Heart Study participants who were examined multiple times as children between 1973 and 1988.

Results

Through 2006, fifteen study participants subsequently developed ESRD in adulthood; seven with no known overt cause. Although the Bogalusa Heart Study population is 63% white and 37% black and 51% male and 49% female, all seven ESRD cases with no known overt cause were black males (p < 0.001). Mean age-adjusted systolic and diastolic blood pressure in childhood was higher among the ESRD cases (114.5 mmHg and 70.1 mmHg, respectively) compared to black (103.0 mmHg and 62.3 mmHg, respectively) and white (mean = 103.3 mmHg and 62.3 mmHg, respectively) boys who didn't develop ESRD. The mean age-adjusted body mass index in childhood was 23.5 kg/m² among ESRD cases and 18.6 kg/m² and 18.9 kg/m² among black and white boys who didn't develop ESRD, respectively. Plasma glucose in childhood was not significantly associated with ESRD.

Conclusion

These data suggest black males have an increased risk of ESRD in young adulthood. Elevated body mass index and blood pressure in childhood may increase the risk for developing ESRD as young adults.

School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6-18

BACKGROUND

The World Health Organization estimates that 1.9 million deaths worldwide are attributable to physical inactivity. Chronic diseases associated with physical inactivity include cancer, diabetes and coronary heart disease.

OBJECTIVES

The purpose of this systematic review is to summarize the evidence of the effectiveness of school-based interventions in promoting physical activity and fitness in children and adolescents.

SEARCH STRATEGY

The search strategy included searching several databases. In addition, reference lists of included articles and background papers were reviewed for potentially relevant studies, as well as references from relevant Cochrane reviews. Primary authors of included studies were contacted as needed for additional information.

SELECTION CRITERIA

To be included, the intervention had to be relevant to public health practice, implemented, facilitated, or promoted by staff in local public health units, implemented in a school setting and aimed at increasing physical activity, report on outcomes for children and adolescents (aged 6 to 18 years), and use a prospective design with a control group.

DATA COLLECTION AND ANALYSIS

Standardized tools were used by two independent reviewers to rate each study's methodological quality and for data extraction. Where discrepancies existed discussion occurred until consensus was reached. The results were summarized narratively due to wide variations in the populations, interventions evaluated and outcomes measured.

MAIN RESULTS

13,841 titles were identified and screened and 482 articles were retrieved. Multiple publications on the same project were combined and counted as one project, resulting in 395 distinct project accounts (studies). Of the 395 studies 104 were deemed relevant and of those, four were assessed as having strong methodological quality, 22 were of moderate quality and 78 were considered weak. In total 26 studies were included in the review. There is good evidence that school-based physical activity interventions have a positive impact on four of the nine outcome measures. Specifically positive effects were observed for duration of physical activity, television viewing, VO2 max, and blood cholesterol. Generally school-based interventions had no effect on leisure time physical activity rates, systolic and diastolic blood pressure, body mass index, and pulse rate. At a minimum, a combination of printed educational materials and changes to the school curriculum that promote physical activity result in positive effects.

AUTHORS' CONCLUSIONS

Given that there are no harmful effects and that there is some evidence of positive effects on lifestyle behaviours and physical health status measures, ongoing physical activity promotion in schools is recommended at this time.

Long-term care in developed countries and recommendations for Slovak Republic

The aging of our population represents a most significant demographic change. It represents important challenges and consequences for the nation's economic, social, and health institutions and for the health and well-being of older persons and their families. Old people over 60 are now the most rapidly growing segment of the population and represent 20% of all Slovak inhabitants. Because of the high prevalence of morbidity and disability among the elderly they are the most important consumers of health care and social care services, both extramural and intramural. Long-term care is a relatively closed system of health care and social care services. Initially, long-term care policies were formulated as a response to ageing of the population, which brought about growing needs of elderly people for social care and health care, and was associated with relatively rapid increases of necessary costs. All industrial countries are facing similar problems when it comes to the integration of long-term care. In developed countries, current long-term care focuses on all age groups in need of assistance and support from others due to the limitations caused by their state of health. Long-term care within the public services system does not exist in Slovakia.

Body mass index in rural first grade schoolchildren: progressive increase in boys

CONTEXT

Childhood overweight is a global health problem. Monitoring of childhood body mass index (BMI) may help identify critical time periods during which excess body weight is accumulated.

PURPOSE

To examine changes in mean BMI and the prevalence of at-risk-for overweight in repeated cross-sectional samples of rural first grade schoolchildren between 1999 and 2004.

METHODS

BMI was determined in 479 first graders from a rural Wyoming school district. BMI and gender-specific BMI-for-age percentiles were determined and evaluated over the 6 years. Children were also classified as normal or at-risk-for overweight according to CDC classification procedures.

FINDINGS

From 1999 to 2004, there was a significant increase in the average BMI of first graders, 15.8+/-2.2 kg/m2 versus 16.8+/-2.2 kg/m2, respectively (P<.05). First grade boys had a progressive increase in BMI from 1999 to 2004 (15.6+/-2.2 kg/m2 compared to 17.3+/-2.2 kg/m2, respectively), but no change was evident for first grade girls. There was an approximate 4-fold increase in the percentage of rural first grade boys classified as at-risk-for overweight between 1999 and 2004.

CONCLUSIONS

A progressive increase in the BMI and the significant increase in prevalence of at-risk-for overweight in rural first grade boys highlight the need for future gender and age group-specific investigations. Focus should be given to primary prevention programs targeting potentially vulnerable time periods when excess weight gain may be occurring.

Subclinical hypothyroidism, hyperhomocysteinemia and dyslipidemia: investigating links with ischemic stroke in Turkish patients

OBJECTIVES

Hyperhomocysteinemia is a risk factor for ischemic stroke. Hypothyroidism may cause hyperhomocysteinemia. To date, no works have examined the association between hypothyroidism and hyperhomocysteinemia in ischemic stroke. We aimed to investigate the roles of hypothyroidism and hyperhomocysteinemia in ischemic stroke, and whether any relationship exists between hypothyroidism and hyperhomocysteinemia in ischemic stroke patients.

METHODS

The study included 249 ischemic stroke patients and 102 patients with no history of stroke. Patients were evaluated for conventional risk factors and levels of homocysteine, thyroid-stimulating hormone, vitamin B12 and folic acid.

RESULTS

Ten (4%) patients in the ischemic stroke group had subclinical hypothyroidism. We did not find any overt or subclinical hypothyroidism in the control group. Hypothyroidism was higher to a statistically significant degree in the ischemic stroke group (p<0.05). Both hyperhomocysteinemia and hypothyroidism were associated with ischemic stroke patients. However, no association was found between hyperhomocysteinemia and hypothyroidism. Ischemic stroke patients with hypothyroidism had lower levels of HDL cholesterol and levels of total cholesterol/HDL-C and LDL-C/HDL-C were higher than those of ischemic stroke patients without hypothyroidism.

DISCUSSION

Hypothyroidism is associated with ischemic stroke. Low HDL cholesterol, high total cholesterol/HDL-C and high LDL-C/HDL-C were associated in ischemic stroke patients with hypothyroidism. Hyperhomocysteinemia was not found to be associated with ischemic stroke patients with hypothyroidism.

Beneficial effects of physical exercise on hypertension and cardiovascular adverse remodeling of diet-induced obese rats

BACKGROUND AND AIMS

Obesity is present among all age groups and in all socioeconomic groups. This study on obese rats aims to quantify the beneficial effects of physical exercise on blood pressure (BP), the heart, the elasticity and resistance of arteries.

METHODS AND RESULTS

Obese male Wistar rats, (obesity due to a high fat diet with 30% fat), and non-obese rats, were assigned to four groups (n=5): sedentary obese; exercise-practice obese; sedentary control; and exercise-practice control (motor treadmill for 13 weeks). Their organs were studied through light microscopy and stereology. The diet-induced obesity caused mild hypertension with adverse cardiovascular changes. Physical exercise diminished the alterations associated with BP elevation and obesity. The pressure-lowering effect observed in obese rats submitted to physical exercise improved the myocardial vascularization and the aortic and the carotid wall structure by reducing the thickness and normalizing both the elastic lamellae and the smooth muscle cells. The adaptive response of the gluteus superficialis muscle to physical exercise also improved the peripheral resistance arteries of obese rats.

CONCLUSION

Current research supports the notion of physical exercise as a potential non-pharmacological antihypertensive treatment for diet-induced obesity hypertension.

Increased levels of C-reactive protein in hypothyroid patients and its correlation with arterial stiffness in the common carotid artery

OBJECTIVE

Hypothyroidism is associated with increased morbidity from cardiovascular disease. The arterial stiffness index beta (stiffness beta) in the common carotid artery (CCA), which is a parameter of arterial stiffening, is known to increase in hypothyroid patients, while normalization of thyroid function for 1 year by levothyroxine (L-T(4)) replacement therapy significantly decreases CCA stiffness beta. Since serum C-reactive protein (CRP) has recently emerged as an independent factor for cardiovascular risk, the present study was designed to examine whether hypothyroidism causes an increase in CRP and whether the serum CRP level is correlated with CCA stiffness beta in hypothyroid patients.

PATIENTS AND METHODS

Serum CRP levels and CCA stiffness beta were determined in 46 patients with hypothyroidism and in 46 age- and sex-matched normal control subjects. Thirty-five patients were further monitored for change in CCA stiffness beta during 1 year in the euthyroid state induced by L-T(4) therapy.

RESULTS

Baseline CRP and CCA stiffness beta were both significantly higher in hypothyroid patients than in normal controls [1064.6+/-224.3 vs. 602.1+/-43.3 ng/ml (mean+/-SE), p<0.0001; and 9.25+/-0.84 vs. 8.21+/-0.85, p<0.05, respectively]. Baseline CRP was significantly correlated in a positive manner with baseline values of CCA stiffness beta (r=0.683, p<0.0001). In multivariate analysis, baseline CCA stiffness beta was significantly associated with baseline levels of serum CRP (r=0.740, p<0.0001). During 1 year of L-T(4) replacement therapy, significant decrease in stiffness beta (from 9.25+/-0.84 to 8.57+/-0.58, p<0.0001) to the normal levels was found. Moreover, the change in CCA stiffness beta during L-T(4) replacement therapy was significantly and independently associated in a negative fashion with baseline levels of serum CRP (r=-0.696, p=0.0002).

CONCLUSIONS

This study suggests that increased serum CRP might have an important independent role in increased arterial stiffening and the measurement of serum CRP is a useful predictor for the degree of improvement of arterial stiffening in hypothyroid patients.

Aerobic fitness and visceral adipose tissue in children

AIM

To determine the relationship between aerobic fitness (peak VO2) and the volume of visceral adipose tissue (VAT) in children.

METHODS

Participants were 30 males (13.7+/-0.5 y) and 22 females (13.5+/-0.5 y). Peak VO2 was determined using a continuous, incremental treadmill protocol to exhaustion. Abdominal VAT volume was measured by magnetic resonance imaging using multiple slices from vertebral levels L1-L5. Subcutaneous body fat measure was calculated as the sum of seven skinfolds (sigma7SKF).

RESULTS

Females had significantly (p < or = 0.05) more VAT than males (1035+/-717.3 vs 678.6+/-361.5 cm3); however, male peak VO2 was higher (215+/-34 vs 182+/-20 ml/kg(0.61)/min). VAT was significantly (p < or = 0.05) negatively correlated with peak VO2 in both males (r = - 0.43) and females (r = - 0.45). Subcutaneous body fatness was significantly correlated with VAT in both males (r = 0.74) and females (r = 0.72), and was the single strongest determinant of VAT.

CONCLUSION

Aerobic fitness is significantly inversely related to VAT, but subcutaneous body fatness is the single strongest determinant of VAT in children aged 13-14 y.

Gap analysis of pediatric reference intervals for risk biomarkers of cardiovascular disease and the metabolic syndrome

The childhood obesity epidemic has begun to compromise the health of the pediatric population by promoting premature development of atherosclerosis and the metabolic syndrome (MS), both of which significantly increase the risk of cardiovascular disease (CVD) early in life. As a result, recently, there has been increased recognition of the need to assess and closely monitor children and adolescents for risk factors of CVD and components of the MS. Serum/Plasma biomarkers including total cholesterol, triglycerides, HDL-C, LDL-C, insulin and C-peptide have been used for this purpose for many years. Recently, emerging biomarkers such as apolipoprotein AI, apolipoprotein B, leptin, adiponectin, free fatty acids, and ghrelin have been proposed as tools that provide valuable complementary information to that obtained from traditional biomarkers, if not more powerful predictions of risk. In order for biomarkers to be clinically useful in accurately diagnosing and treating disorders, age-specific reference intervals that account for differences in gender, pubertal stage, and ethnic origin are a necessity. Unfortunately, to date, many critical gaps exist in the reference interval database of most of the biomarkers that have been identified. This review contains a comprehensive gap analysis of the reference intervals for emerging and traditional risk biomarkers of CVD and the MS and discusses the clinical significance and analytical considerations of each biomarker.

Tracking of overweight status from childhood to young adulthood: the Bogalusa Heart Study

OBJECTIVE

To understand tracking of overweight status from childhood to young adulthood in a biracial sample.

DESIGN

A longitudinal sample was created from cross-sectional surveys at two time points, childhood (baseline) and young adulthood (follow-up).

SETTING

Bogalusa Heart Study, Louisiana, United States of America.

SUBJECTS

A total of 841 young adults, 19-35 years (68% Euro-Americans (EA), 32% African-Americans (AA)) were studied. The same subjects had also participated in one of the five cross-sectional surveys at childhood (9-11 years).

METHODS

Body mass index (BMI) was used to determine overweight status as per the Centers for Disease Control and Prevention standards. Change in the BMI status from childhood to young adulthood was used to group the participants into the following categories: normal weight to normal weight (NW-NW); normal weight to overweight (NW-OW); overweight to normal weight (OW-NW); and overweight to overweight (OW-OW). Tracking of overweight was defined by (1) correlations between baseline and follow-up BMI, (2) Cohen's kappa concordance test to determine the strength of tracking in BMI quartiles and (3) the percentage of individuals who remained in the same overweight status group from baseline to follow-up.

RESULTS

From baseline to follow-up, the percentage of participants who were overweight increased from 24.7 to 57.7%. A total of 35.2% of the children shifted from normal weight in childhood to overweight in young adulthood (P < 0.0005). Baseline BMI was positively correlated with follow-up BMI (r = 0.66, P < 0.0005). A total of 61.9% of the participants in the highest BMI quartile in childhood remained in the highest BMI quartile in young adulthood. The strength of tracking in BMI quartiles was 27% for EA men (P < 0.0005), 23% for EA women (P < 0.0005), 27% for AA men (P<0.0005) and 35% for AA women (P < 0.0005). A total of 53.7% of the EA women remained in the NW-NW category and 31.2% of the AA women remained in the OW-OW category. The percentage tracking (NW-NW and OW-OW) was 72.8% in EA women, 59.6% in AA men, 59.5% in AA women and 48.8% in EA men (P < 0.0001).

CONCLUSION

Childhood overweight tracked into young adulthood in this sample and the tracking of NW-NW and OW-OW was the most prominent among the EA women.

Spectrum and prevalence of atherogenic risk factors in 27,358 children, adolescents, and young adults with type 1 diabetes: cross-sectional data from the German diabetes documentation and quality management system (DPV)

OBJECTIVE

The aim of this data analysis was to ascertain the type and prevalence rate as well as age and sex distribution of cardiovascular risk factors in type 1 diabetic patients up to 26 years of age.

RESEARCH DESIGN AND METHODS

Cardiovascular risk factors such as obesity, hypertension, dyslipidemia, poor glycemic control, and smoking were analyzed in 27,358 patients who were divided into three groups (prepubertal, pubertal, and adult) using specifically designed diabetes software for prospective disease documentation.

RESULTS

More than half of the patients per age-group had at least one cardiovascular risk factor. Two risk factors were age dependently found in 6.2-21.7% and three or four risk factors in 0.5-4.7%. Elevated values of HbA(1c), total cholesterol, and BMI were found most frequently. Hypertension, smoking, and HDL cholesterol were observed more frequently in males, and elevated BMI, total cholesterol, and LDL cholesterol more often in females. Although 28.6% of the patients had dyslipidemia, merely 0.4% of them received medical treatment, and of the 8.1% of the patients with hypertension, only 2.1% of them were given antihypertensive medication.

CONCLUSIONS

With increasing age, a greater number of patients with cardiovascular risk factors were observed. Significant sex differences were seen in the majority of risk factors. Despite the high prevalence of risk factors, only a small minority of patients received antihypertensive or lipid-lowering treatment. Early identification, prevention, and treatment of additional risk factors seem to be necessary, particularly in light of the high incidence of future cardiovascular disease.

Plasma levels of adiponectin and soluble thrombomodulin in hypothyroid patients with normal thyroid function following levothyroxine replacement therapy

Hypothyroidism is associated with increased morbidity from cardiovascular disease, and adiponectin (ApN) is a newly-identified adipocytokine, which is expressed in human adipose cells and may have a protective effect against the development of coronary artery disease. The aim of the study was to evaluate the involvement of ApN secretion in hypothyroid patients with normal thyroid function following levothyroxine (L-T(4)) replacement therapy, and to associate plasma ApN levels with intima-media thickness (IMT) in the common carotid artery (CCA), an indicator of early atherosclerosis, and cardiovascular parameters including soluble thrombomodulin (sTM), a plasma endothelial injury marker. The CCA IMT and plasma levels of ApN and sTM were measured in 52 hypothyroid patients and in age-, sex- and body mass index (BMI)-matched normal control subjects. Thirty-six of the hypothyroid patients were further monitored for changes in these markers during 1 year in a euthyroid state induced by L-T(4) replacement therapy. Although the basal CCA IMT was significantly higher in hypothyroid patients [0.633 +/- 0.018 mm (mean +/- S.E.)] than in control subjects (0.552 +/- 0.022 mm, P < 0.005), both groups had similar baseline ApN and sTM levels [10.23 +/- 0.76 vs. 10.10 +/- 0.93 microg/ml: NS; and 2.58 +/- 0.14 vs. 2.68 +/- 0.20 ng/ml: NS, respectively]. Simple regression analysis revealed that plasma ApN was significantly correlated in a positive manner with age (r = 0.339, P = 0.015), HDL-cholesterol (r = 0.295, P = 0.048), and sTM (r = 0.490, P = 0.0005), but not with CCA IMT (r = 0.059, P = 0.742). In multivariate analysis, the plasma ApN level was significantly associated with that of sTM (r = 0.546, P = 0.0001) and with serum high-density lipoprotein (HDL)-cholesterol levels (r = 0.291, P = 0.029) in hypothyroid patients. During 1 year of L-T(4) replacement therapy, hypothyroid patients showed a significant decrease in CCA IMT, to 0.553 +/- 0.016 mm (P < 0.0001), a level comparable to normal controls, but no significant change in ApN (from 10.79 +/- 1.07 to 10.6 9+/- 1.14 microg/ml, NS) or sTM (from 2.59 +/- 0.15 to 2.74 +/- 0.18 ng/ml, NS). Hence, we provide evidence that ApN and sTM might not contribute to enhanced atherosclerosis, as reflected by increased CCA IMT in hypothyroid patients. However, this is the first report to demonstrate a positive and significant association of sTM with ApN. These data support the hypothesis that sTM is one of the determinant of ApN and thus suggest the presence of an sTM-associated regulatory mechanism for ApN secretion in hypothyroid patients.

Biochemical and behavioral indices related to BMI in schoolchildren in urban Turkey

BACKGROUND

The aim of the current study was to examine the interrelationship between certain cardiovascular disease (CVD) risk factors and overweight, as well as to provide some indication on the prevalence of underweight, overweight and obesity in primary schoolchildren in urban Turkey.

METHODS

1044 randomly selected children aged 12 and 13 years old from the urban areas of Istanbul, Ankara and Izmir were examined. The main variables of interest were fatness determined by body mass index and sum of skinfolds, lipid profile, dietary intake, physical fitness and habitual physical activity.

RESULTS

Both overweight boys and girls were found to have lower cardiovascular fitness levels compared to their normal weight peers. Overweight boys reported lower energy and macronutrient intake than their normal weight counterparts. Regarding biochemical indices, overweight boys were found to have higher total cholesterol (TC), Low Density Lipoprotein-cholesterol (LDL-C), triglycerides (TG) and LDL-C/HDL-C ratio compared to normal weight boys, while overweight girls were found to have lower High Density Lipoprotein-cholesterol (HDL-C) and higher TG compared to their normal weight peers. Finally, the prevalence of underweight, overweight and obesity for the overall population was found to be 12%, 12% and 2%, respectively.

CONCLUSIONS

The study revealed that overweight and obesity in children coexisted with more unfavorable lipid profiles and lower cardiovascular fitness levels. This finding points out the emergent need for suitable measures to be implemented in order to identify and counteract these health and social problems early in life.

Increased fasting plasma insulin concentrations are associated with the severity of angiographic coronary artery disease

Fasting plasma insulin concentrations were obtained in 82 patients (51 men and 31 women), mean age 60 +/- 11 years, with a body mass index >25 kg/m(2) who had coronary angiography because of suspected symptomatic coronary artery disease (CAD). Obstructive CAD was diagnosed if there was >50% obstruction of > or =1 vessel. Of 82 patients, 37 (45%) had left main or 3-vessel CAD, 22 (27%) had 2-vessel CAD, 9 (11%) had 1-vessel CAD, and 14 (17%) had no obstructive CAD. Among the 4 groups, there was no significant difference in gender, age, dyslipidemia, and smoking. Hypertension (p = 0.0003), diabetes mellitus (p = 0.035), and increased fasting plasma insulin concentration (p < 0.0001) were significantly associated with the severity of CAD. Stepwise ordinal logistic regression analysis identified increased fasting plasma insulin concentrations in these obese subjects as a significant independent risk factor for the severity of angiographic CAD (p < 0.0001).

Increased levels of serum osteoprotegerin in hypothyroid patients and its normalization with restoration of normal thyroid function

Hypothyroidism is associated with increased morbidity from cardiovascular disease, and an increase in serum osteoprotegerin (OPG) has recently been reported to be associated with the severity of coronary heart disease and cardiovascular mortality. The present study was designed to examine whether hypothyroidism causes an increase in serum OPG, and to determine whether levothyroxine (L-T4) replacement therapy might suppress serum OPG levels in hypothyroid patients. Fifty-three hypothyroid patients with chronic thyroiditis and age- and sex-matched normal control subjects were examined for the levels of serum OPG and plasma von Willebrand factor (vWF), a vascular injury marker. Thirty-seven of the hypothyroid patients were further monitored for changes in these markers during 1 year in a euthyroid state induced by L-T4 replacement therapy. Baseline OPG was significantly higher in hypothyroid patients than in normal controls (4.51 +/- 0.50 vs 3.72 +/- 0.23 pmol/l (mean +/- S.E.); P = 0.0182). In multivariate analysis, baseline OPG was significantly associated with baseline levels of TSH (r = 0.280, P = 0.0162) and vWF (r = 0.626, P < 0.0001). During one year of L-T4 replacement therapy, hypothyroid patients showed a significant decrease in OPG levels from 4.35 +/- 0.51 to 3.48 +/- 0.26 pmol/l (P = 0.0166), a level comparable to normal controls. The change in serum OPG levels during L-T4 replacement therapy was significantly and independently associated in a negative fashion with baseline vWF (r = -0.503, P = 0.0014). This study suggested that the severity of hypothyroidism and vascular injury might have important independent roles in increasing the serum OPG level in hypothyroid patients. Furthermore, it was demonstrated that a sustained euthyroid state might have the potential to decrease the serum OPG level in hypothyroid patients and that the degree of vascular injury in the hypothyroid state is independently associated with a decrease in serum OPG during a 1-year normalization of thyroid function.

Decrease of arterial stiffness at common carotid artery in hypothyroid patients by normalization of thyroid function

This study examined the effect of hypothyroidism on arterial stiffening and the effect of levothyroxine (l-T(4)) replacement. The arterial stiffness index beta (stiffness beta) and intima-media thickness (IMT), a parameter of arterial stiffening and thickening, respectively, were determined in common carotid artery (CCA) by ultrasonography in 30 hypothyroid patients before and after 1 year of normalization of thyroid function by l-T(4) replacement. Baseline CCA stiffness beta and IMT was significantly higher in the hypothyroid patients than in age- and sex-matched normal controls [9.46 +/- 0.93 vs. 8.02 +/- 0.91 (mean +/- SE); P < 0.05, 0.635 +/- 0.018 mm vs. 0.541 +/- 0.019 mm; P < 0.005, respectively]. In multivariate analysis, baseline stiffness beta was significantly associated with baseline levels of IMT (r = 0.457, P = 0.0311), FT(4) (r = -0.413, P = 0.0169), and a plasma vascular injury marker, von Willebrand factor (vWF) (r = 0.412, P = 0.0261). During 1 year of euthyroidism, 22 and 29 out of 30 patients showed significant decreases of stiffness beta and IMT to normal respective level, from 9.46 +/- 0.93 to 7.58 +/- 0.34 and from 0.635 +/- 0.018 to 0.552 +/- 0.015 mm, respectively. Change in stiffness beta during l-T(4) therapy correlated significantly in a negative manner with baseline levels of age (r = -0.465, P = 0.011) and IMT (r = -0.406, P = 0.029). Stiffness beta after but not before l-T(4) therapy showed a tendency towards a positive correlation with age. This study suggested that increases of arterial thickening, and plasma vWF, and a reduction in serum FT(4) might have an important role independently in the increased arterial stiffening in hypothyroid patients. Furthermore, it was demonstrated that sustained euthyroidism might have the potential to reverse arterial stiffening in addition to thickening in hypothyroid patients.

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.

Current and adolescent body fatness and fat distribution

OBJECTIVE

Body fat and its distribution are determinants of cardiovascular disease but the underlying mechanisms of these adverse effects are poorly understood. We therefore investigated (1) the cross-sectional relationship between estimates of body fatness and its distribution on the one hand and carotid atherosclerosis and stiffness of the carotid, femoral and brachial arteries and the carotido-femoral segment on the other (336 subjects, 175 women); (2) the relationship between estimates of body fatness and its distribution during adolescence (13-16 years) and the same arterial properties at age 36- prospective analyses (subpopulation of 159 subjects, 84 girls).

DESIGN

Cross-sectional and prospective analyses within an ongoing observational longitudinal study: The Amsterdam Growth and Health Longitudinal Study.

METHODS

Body fatness and its distribution were assessed by anthropometry and dual-energy X-ray absorptiometry (DXA); arterial properties were assessed non-invasively by ultrasound imaging.

RESULTS

Total adiposity and, in men, truncal subcutaneous fat accumulation during adolescence, were positively and independently associated with carotid intima-media thickness at age 36, a pre-clinical indicator of atherosclerosis. Adolescent truncal subcutaneous fat accumulation but not total adiposity was associated with increased arterial stiffness at age 36. At age 36, both abdominal and truncal subcutaneous fat were independently associated with arterial stiffness, while the associations between total adiposity and arterial stiffness appeared to be mediated by other cardiovascular risk factors.

CONCLUSIONS

Body fatness and body fat distribution are associated with large artery structural and functional properties at age 36 and the roots of these associations may already be present in adolescence.

Impact of television viewing patterns on fruit and vegetable consumption among adolescents

BACKGROUND

National data indicate that children and youth do not meet Healthy People 2010 objectives for fruit and vegetable intake. Television viewing is hypothesized as a contributing factor because of its documented role in encouraging consumption of highly advertised foods that may lead to the replacement of fruits and vegetables.

METHODS

A sample of 548 ethnically diverse students (average age: 11.7 +/- 0.8 years) from public schools in 4 Massachusetts communities were studied prospectively over a 19-month period from October 1995 to May 1997. We examined the associations between baseline and change in hours of television and video viewing per day (the predictor variables) and change in energy-adjusted intake of fruits and vegetables by using linear regression analyses to control for potentially confounding variables and the clustering of observations within schools.

FINDINGS

For each additional hour of television viewed per day, fruit and vegetable servings per day decreased (-0.14) after adjustment for anthropometric, demographic, dietary variables (including baseline percent energy from fat, sit-down dinner frequency, and baseline energy-adjusted fruit and vegetable intake), and physical activity. Baseline hours of television viewed per day was also independently associated with change in fruit and vegetable servings (-0.16).

CONCLUSIONS

Television viewing is inversely associated with intake of fruit and vegetables among adolescents. These associations may be a result of the replacement of fruits and vegetables in youths' diets by foods highly advertised on television.

Clustered features of the metabolic syndrome and the risk for increased aortic pulse wave velocity in middle-aged Japanese men

The association between different features of the metabolic syndrome (MS) (obesity, hypertension, hypercholesterolemia, low high-density lipoprotein cholesterol level, hypertriglyceridemia, high fasting plasma glucose level, and hyperuricemia) and the risk for increased aortic pulse wave velocity (PWV) of > or = 8.0 m/sec was examined in 2431 Japanese men aged 35 to 54 years who were not taking antihypertensive medication. After controlling for age, cigarette smoking, and alcohol intake, the odds ratios for increased aortic PWV in subjects with 1, 2, 3, and > or = 4 features of the MS, compared with those without features of the MS, were 1.35 (95% CI, 0.86 to 2.11), 1.90 (95% CI, 1.18 to 3.06), 1.57 (95% CI, 0.89 to 2.76), and 2.38 (95% CI, 1.26 to 4.49), respectively (p for trend = 0.003). A 9-year longitudinal study was also performed to prospectively examine the association between clustered features of the MS and the development of increased aortic PWV in 2073 men without aortic stiffness with a PWV < 8.0 m/sec and without antihypertensive medication during the follow-up period. The multivariate-adjusted hazard ratios for the incidence of increased aortic PWV in subjects with 1, 2, 3, and > or = 4 features of the MS, compared with those without features of the MS, were 1.39 (95% CI, 1.10 to 1.77), 1.46 (95% CI, 1.1 1 to 1.92), 1.75 (95% CI, 1.27 to 2.40), and 2.22 (95% CI, 1.52 to 3.25), respectively (p for trend < 0.001). These results suggest that clustered features of the MS are closely associated with the risk for increased aortic PWV in middle-aged Japanese men.

Decrease in carotid intima-media thickness in hypothyroid patients after normalization of thyroid function

OBJECTIVE

This case-control study was carried out to assess whether levothyroxine (L-T4) replacement might cause regression of the enhanced atherosclerosis seen in hypothyroid patients.

PATIENTS AND METHODS

Intima-media thickness (IMT) in the common carotid artery (CCA) was measured from digitalized still images taken during scanning by high-resolution ultrasonography as an indicator of early atherosclerosis. Thirty-five hypothyroid patients were examined for their CCA IMT before and 1 year after normalization of thyroid function by L-T4 replacement. As control, 35 healthy subjects were enrolled from among the participants in a local health-check programme conducted at the Osaka City University Hospital.

RESULTS

Basal CCA IMT was significantly higher in hypothyroid patients [0.635 +/- 0.018 (mean +/- SE) mm] than in control subjects (0.559 +/- 0.021 mm, P < 0.005). After 1 year of euthyroidism, 34 out of 35 patients showed a significant decrease of CCA IMT, to 0.552 +/- 0.015 mm (P < 0.0001), a level comparable to normal controls. CCA IMT change was closely associated with basal levels of total cholesterol (r = -0.472, P= 0.0031), low-density lipoprotein (LDL) cholesterol (r = -0.441, P= 0.0076) and the total/HDL cholesterol ratio (r =-0.435, P= 0.0057), but not with any of the other variables measured except for age (r = -0.353, P= 0.0296).

CONCLUSIONS

This study demonstrated that L-T4 treatment might have the potential to reverse the progression of atherosclerosis in hypothyroid patients. Furthermore, it suggests that increased levels of LDL cholesterol and the total/HDL cholesterol ratio have an important role in the increased common carotid intima-media thickness in hypothyroid patients.

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.

Carotid artery intimal-medial thickness and left ventricular hypertrophy in children with elevated blood pressure

OBJECTIVES

To determine the association between carotid artery intimal-medial thickness (cIMT) and left ventricular mass index (LVMI) in children with elevated blood pressure.

METHODS

Study subjects (n = 32; mean age: 13.9 +/- 2.7 years) were untreated new referrals to a pediatric hypertension clinic with confirmed elevated blood pressure. LVM was calculated from 2-dimensionally guided m-mode echocardiographic measurements of the left ventricle. LVMI was calculated as LVM (g)/height (m)2.7, and left ventricular hypertrophy (LVH) was defined as LVMI >95th percentile. Carotid artery duplex ultrasound was performed by protocol by experienced vascular sonographers who were unaware of the echocardiography results. The thickest IMT complex of the far wall of the distal common carotid artery was measured in longitudinal B-mode section using a high-resolution linear array of 8 MHz.

RESULTS

The prevalence of LVH and increased cIMT was 41% and 28%, respectively. Subjects with increased cIMT had higher LVMI (46.8 g/m2.7 vs 31.4 g/m2.7) than those with normal cIMT. The LVH prevalence was 89% (8 of 9) among subjects with increased cIMT as compared with 22% (5 of 23) in subjects with normal cIMT. cIMT was positively correlated with body mass index (r = 0.43), interventricular septal thickness (r = 0.58), posterior wall thickness (r = 0.54), and LVMI (r = 0.54). cIMT and LVMI were positively associated after accounting for age, gender, and body mass index.

CONCLUSIONS

These findings raise the possibility that carotid duplex ultrasound, by indicating the presence of early arterial wall changes, may be useful for predicting other cardiovascular sequelae in hypertensive children.