Predictors of circulating endothelial progenitor cell levels in patients without known coronary artery disease referred for multidetector computed tomography coronary angiography.

INTRODUCTION: Endothelial progenitor cells (EPCs) have an important role in vascular repair. Levels in peripheral circulation are thought to be related to overall cardiovascular risk and may represent potential therapeutic targets. The aim of this work is to identify predictors of circulating EPC concentrations in patients without known coronary artery disease (CAD). METHODS: The study population consisted of 215 patients without known CAD referred for multidetector computed tomography (MDCT) coronary angiography (CTA) during a 6-month period. All patients underwent: 1) short anamnesis; 2) anthropometric measurements; 3) blood pressure and heart rate assessment; 4) blood tests; and 5) MDCT (including quantification of visceral fat, quantification of coronary artery calcification [CAC] and CTA). RESULTS: The patients' mean age was 58±11 years (26-84) and 61% were male. Dyslipidemia (59%) and hypertension (57%) were the most prevalent risk factors. Twenty-seven percent met the ATP III criteria for metabolic syndrome. Mean Framingham risk score was 12±9%. Sixty-seven percent had no significant CAD but 64% had some degree of coronary calcification. The mean CAC (Agatston) was 186±433. Mean EPC concentration, expressed as a percentage of total white blood cells, was 0.05±0.08% (0.0-0.58%). EPCs were inversely related to the presence of diabetes mellitus and smoking, and positively related to C-reactive protein. No significant correlations were found between EPCs and other risk factors, measurements of adiposity, atherosclerotic burden or severity of CAD. CONCLUSION: In patients without known CAD referred for MDCT, EPC levels in peripheral blood cannot be significantly estimated or predicted from knowledge of patient anamnesis, risk factors, visceral fat, CAC or CTA.

Is low birth weight in the causal pathway of the association between maternal smoking in pregnancy and higher BMI in the offspring?

A number of cross-sectional and prospective studies suggested a priming effect of maternal smoking in pregnancy on offspring's obesity. It has been hypothesized that this association might be explained by low birth weight and subsequent catch-up growth in the causal pathway. We therefore examined the role of birth weight in children exposed versus not exposed to cigarette smoking in utero on later body mass index (BMI). Using data of 12,383 children and adolescents (3-17 years of age) recorded in a German population-based survey (KiGGS), we assessed mean body mass index standard deviation scores (BMI-SDS) in different birth weight SDS categories, stratified for children with smoking and non-smoking mothers. We calculated spline regression models with BMI-SDS as outcome variable, cubic splines of birth weight SDS, and potential confounding factors. Children whose mothers had been smoking during pregnancy had lower birth weight SDS and higher BMI-SDS at interview compared to children of non-smoking mothers. However, we observed a linear association between birth weight SDS and BMI-SDS in crude analyses for both groups. Similarly, almost linear effects were observed in adjusted spline regression analyses, except for children with very low birth weight. The respective 95% confidence bands did not preclude a linear effect for the whole birth weight SDS distribution. Our findings suggest that low birth weight is unlikely to be the main cause for the association between intrauterine nicotine exposure and higher BMI in later life. Alternative mechanisms, such as alterations in the noradrenergic system or increased food efficiency, have to be considered.

Longitudinal association between IGFBP-1 levels and parameters of the metabolic syndrome in obese children before and after weight loss.

BACKGROUND: Insulin-like growth factor binding protein 1 (IGFBP-1) is a marker of insulin resistance. We hypothesized that IGFBP-1 is associated with the metabolic syndrome (MetS), which is related to insulin resistance. METHODS: We examined 51 obese Caucasian children (mean age 12.1 ? 2.3, 55% male, mean body mass index [BMI] 31.8 ? 4.8 kg/m(2)). Anthropometrical markers, pubertal stage, hepatic ultrasound, waist circumference, blood pressure, fasting serum IGFBP-1, IGFBP-3, IGF-I, adiponectin, leptin, transaminases, glucose, insulin, triglycerides, and HDL-cholesterol concentrations were determined at onset and the end of the one-year lifestyle intervention. RESULTS: In contrast to IGF-I and IGFBP-3, IGFBP-1 correlated significantly to most parameters of the MetS in cross-sectional (waist circumference: r = -0.45, triglycerides: r = -0.29; insulin: r = -0.31; HOMA: r = -0.30) and longitudinal analyses (? triglycerides: r = ?0.22; ? Insulin: r = ?0.25; ? HOMA: r = ?0.62). The association between changes of HOMA and changes of IGFBP-1 was stronger than the associations between changes of leptin or adiponectin, and changes of HOMA. The risk for the MetS was inversely related to IGFBP-1 levels (odds ratio:-0.05 per additional IGFBP-1 unit; 95% confidence interval: -0.08 up to -0.02; p = 0.019) in a multiple logistic regression analyses adjusted to BMI, pubertal stage, age, and gender. The nine obese children with the MetS had significantly lower IGFBP-1 levels (1.6 ? 1.3 ngm/l) than the 42 obese children without the MetS (4.0 ? 3.8 ng/ml). The eleven obese children with fatty liver assessed by ultrasound had significantly lower IGFBP-1 levels (1.5 ? 1.3 ngm/l) than the 40 obese children without fatty liver (4.2 ? 4.1 ng/ml). CONCLUSION: The strong relationships between IGFBP-1, insulin resistance, and the MetS suggest that IGFBP-1 might be a promising marker for these entities in obesity. This study is registered at clinicaltrials.gov (NCT00435734).

Body mass index patterns over 5 y in obese children motivated to participate in a 1-y lifestyle intervention: age as a predictor of long-term success.

BACKGROUND: Long-term outcome after lifestyle interventions in obese children is largely unknown but important to improving intervention. OBJECTIVE: The aim was to identify predictors of long-term changes in body mass index (BMI) after lifestyle intervention. DESIGN: Annual changes in the BMI SD score (BMI-SDS) over 5 y in 663 obese children (aged 4-16 y) motivated to participate in an outpatient lifestyle intervention were analyzed. Child-specific longitudinal curves based on multilevel growth curve models (MLMs) over 5 y were estimated depending on patient characteristics (age and sex). RESULTS: The mean decrease in BMI-SDS was 0.36 (95% CI: 0.33, 0.39) at the end of the 1-y intervention and 0.46 (95% CI: 0.36, 0.55) 4 y after the intervention. Change in BMI-SDS in the intervention period predicted long-term outcome after 5 y (P < 0.001). MLMs identified age but not sex as a predictor of the outcome: the youngest children (<8 y) at the onset of the intervention had the greatest decrease in BMI-SDS over 5 y, and the oldest children (>13 y) had the least decrease in BMI-SDS (P < 0.05). Whereas there was a larger reduction in BMI-SDS during the intervention in children aged 8-10 y than in children aged 11-12 y, long-term decrease in BMI-SDS was greater in 11-12-y-old children (P < 0.001). CONCLUSIONS: Younger age was associated with the best long-term outcome after participation in the lifestyle intervention, which supports the need for early intervention in childhood obesity. Children aged 8-10 y may need modified intervention, because BMI-SDS increased more in the older children in the long term. However, mean BMI-SDS was significantly lower 4 y after the end of the intervention than at baseline in all age groups. This study was registered at clinicaltrials.gov as NCT00435734.

Declining 1-year case-fatality of stroke and increasing coverage of vascular risk management: population-based cohort study.

BACKGROUND: The authors estimated trends in 1-year case-fatality of stroke in relation to changes in vascular risk management from 1997 to 2005. METHODS: A cohort study was implemented using data for 407 family practices in the UK General Practice Research Database, including subjects with first acute strokes between 1997 and 2005. One-year case-fatality was estimated by year and sex. Rate ratios were estimated using Poisson regression. RESULTS: There were 19 143 women and 16 552 men who had first acute strokes between 1997 and 2005. In women, the 1-year case-fatality declined from 41.2% in 1997 to 29.2% in 2005. In men, the decline was from 29.2% in 1997 to 22.2% in 2005. The proportion of general practices that prescribed antihypertensive drugs to two-thirds or more of new patients with stroke increased from 6% in 1997 to 48% in 2005, for statins from 1% to 39% and for antiplatelet drugs from 11% to 39%. The rate ratio for 1-year mortality in 2005, compared with 1997-1998, adjusted for age group, sex, prevalent coronary heart disease, prevalent hypertension and deprivation quintile was 0.79 (0.74 to 0.86, p<0.001). After adjustment for antihypertensive, statin and antiplatelet prescribing, the rate ratio was 1.29 (1.17 to 1.42). CONCLUSIONS: Reducing 1-year case-fatality after acute stroke may be partly explained by increased prescribing of antihypertensive, statin and antiplatelet drugs to patients with recent strokes. However, these analyses did not include measures of possible changes over time in stroke severity or acute stroke management.

Former small for gestational age (SGA) status is associated to changes of insulin resistance in obese children during weight loss.

OBJECTIVE: Former small for gestational age (SGA) children are at risk of both obesity and insulin resistance. Longitudinal studies are required to assess a possible relationship between former SGA status and insulin resistance independent of weight status. We hypothesized that obese children with former appropriate for gestational age (AGA) status improve their insulin resistance during weight loss more effectively compared to obese children with former SGA status. METHODS: A 1-yr longitudinal follow-up study design was adopted in the primary care setting and 341 obese children [8% SGA, mean age 10.5 +/- 0.1 yr, body mass index (BMI) 27.7 +/- 0.2, BMI-standard deviation score (SDS) 2.47 +/- 0.02] were taken for the study. Outpatient 1-yr intervention was based on exercise, behavior and nutrition therapy. We measured insulin resistance index following the Homeostasis model assessment model (HOMA), blood pressure, lipids, glucose, and insulin in all children before and after the 1-yr intervention. RESULTS: In a multiple linear regression analysis adjusted for age, gender, and pubertal stage, changes of HOMA were significantly related to changes of BMI-SDS (-2.55 per loss of 1 BMI-SDS unit; p < 0.001) and SGA status (+2.05 for SGA children; p < 0.001). Changes of BMI-SDS together with gender and age explained 10% of the variance of changes of HOMA, while SGA status explained an additional 4%. After adjustment for age, sex, pubertal stage, and BMI-SDS, former SGA status was not significantly related to any other considered cardiovascular risk factor. CONCLUSIONS: Change of weight status predicted change of HOMA in obese children participating in a lifestyle intervention. Changes of HOMA were also predicted by former SGA status supporting that former SGA status influences insulin resistance.

Meal patterns and frequencies: do they affect body weight in children and adolescents?

Some previous studies reported a higher meal frequency associated with a lower body weight both in obese and in normal weight adults. We review recent studies addressing the relation between meal frequency and obesity risk in children and adolescents. In a Medline search, we identified 5 observational studies published between 2004 and 2009 that reviewed data on a total of 13,998 children and adolescents from the United States, Germany, and Portugal. Three of the five studies found a significant reduction of obesity risk with increasing number of meals, which persisted after adjustment for confounders, while the two other studies found a non-significant trend in the same direction. Given the consistent association of skipping meals with an increased obesity risk in children, it appears prudent to promote a regular meal pattern with 5 meals per day with adequate composition to children and their families. Prospective controlled trials to assess the protective potential of promoting regular and frequent meals in children and their families are highly desirable to strengthen the evidence base for such preventive approaches, which should explore the feasibility and effects of interventions.

Noninvasive assessment of pulmonary artery flow and resistance by cardiac magnetic resonance in congenital heart diseases with unrestricted left-to-right shunt.

OBJECTIVES: To determine whether noninvasive assessment of pulmonary artery flow (Qp) by cardiac magnetic resonance (CMR) would predict pulmonary vascular resistance (PVR) in patients with congenital heart disease characterized by an unrestricted left-to-right shunt. BACKGROUND: Patients with an unrestricted left-to-right shunt who are at risk of obstructive pulmonary vascular disease require PVR evaluation preoperatively. CMR cardiac catheter (XMR) combines noninvasive measurement of Qp by phase contrast imaging with invasive pressure measurement to accurately determine the PVR. METHODS: Patients referred for clinical assessment of the PVR were included. The XMR was used to determine the PVR. The noninvasive parameters, Qp and left-to-right shunt (Qp/Qs), were compared with the PVR using univariate regression models. RESULTS: The XMR was undertaken in 26 patients (median age 0.87 years)-ventricular septal defect 46.2%, atrioventricular septal defect 42.3%. Mean aortic flow was 2.24 +/- 0.59 l/min/m(2), and mean Qp was 6.25 +/- 2.78 l/min/m(2). Mean Qp/Qs was 2.77 +/- 1.02. Mean pulmonary artery pressure was 34.8 +/- 10.9 mm Hg. Mean/median PVR was 5.5/3.0 Woods Units (WU)/m(2) (range 1.7 to 31.4 WU/m(2)). The PVR was related to both Qp and Qp/Qs in an inverse exponential fashion by the univariate regression equations PVR = exp(2.53 - 0.20[Qp]) and PVR = exp(2.75 - 0.52[Qp/Qs]). Receiver-operator characteristic (ROC) analysis was used to determine cutoff values for Qp and Qp/Qs above which the PVR could be regarded as clinically acceptable. A Qp of > or =6.05 l/min/m(2) predicted a PVR of < or =3.5 WU/m(2) with sensitivity 72%, specificity 100%, and area under the ROC curve 0.90 (p = 0.002). A Qp/Qs of > or =2.5/1 predicted a PVR of < or =3.5 WU/m(2) with sensitivity 83%, specificity 100%, and area under the curve ROC 0.94 (p < 0.001). CONCLUSIONS: Measurement of Qp or left-to-right shunt noninvasively by CMR has potential to predict the PVR in patients with an unrestricted left-to-right shunt and could potentially determine operability without having to undertake invasive testing.

Multislice computed tomography in the exclusion of coronary artery disease in patients with presurgical valve disease.

BACKGROUND: Multislice computed tomography (MSCT) has shown high negative predictive value in ruling out obstructive coronary artery disease. Preliminary studies in patients with valvular heart disease (VHD) have demonstrated the potential of MSCT angiography (CTA) in such patients, precluding need for invasive angiography (XA). However, larger prospectively designed studies, including patients with atrial fibrillation and incorporating dose reduction algorithms, are needed. METHODS AND RESULTS: To evaluate the clinical utility of 64-slice CT in the preoperative assessment in patients with VHD, we prospectively studied 452 consecutive patients undergoing routine cardiac catheterization for eligibility. Two hundred thirty-seven patients underwent both MSCT and XA. Segment-based, vessel-based, and patient-based agreement between CTA and XA was estimated assuming that "nonevaluable" segments were positive for significant coronary stenosis. In a patient-based analysis, sensitivity, specificity, positive predictive value, and negative predictive values of CTA were 95%, 89%, 66%, and 99%, respectively; in vessel-based analysis, 90%, 92%, 48%, and 99%, respectively; and in segment-based analysis, 89%, 97%, 38%, and 100%, respectively. No significant differences were found between patients with or without atrial fibrillation. A CAC value of 390 was the best cutoff for the identification of patients with positive or inconclusive CTA (which would not be exempted from XA in the clinical setting). CONCLUSIONS: In the preoperative assessment of patients with predominant VHD, the diagnostic accuracy of 64-slice CTA for ruling out the presence of significant coronary artery disease is very good even when including patients with irregular heart rhythm. Using this approach, CAC quantification before CTA can be successfully used to identify patients who should be referred directly to XA, sparing unnecessary exposure to radiation.

Selection of medical diagnostic codes for analysis of electronic patient records. Application to stroke in a primary care database.

BACKGROUND: Electronic patient records from primary care databases are increasingly used in public health and health services research but methods used to identify cases with disease are not well described. This study aimed to evaluate the relevance of different codes for the identification of acute stroke in a primary care database, and to evaluate trends in the use of different codes over time. METHODS: Data were obtained from the General Practice Research Database from 1997 to 2006. All subjects had a minimum of 24 months of up-to-standard record before the first recorded stroke diagnosis. Initially, we identified stroke cases using a supplemented version of the set of codes for prevalent stroke used by the Office for National Statistics in Key health statistics from general practice 1998 (ONS codes). The ONS codes were then independently reviewed by four raters and a restricted set of 121 codes for 'acute stroke' was identified but the kappa statistic was low at 0.23. RESULTS: Initial extraction of data using the ONS codes gave 48,239 cases of stroke from 1997 to 2006. Application of the restricted set of codes reduced this to 39,424 cases. There were 2,288 cases whose index medical codes were for 'stroke annual review' and 3,112 for 'stroke monitoring'. The frequency of stroke review and monitoring codes as index codes increased from 9 per year in 1997 to 1,612 in 2004, 1,530 in 2005 and 1,424 in 2006. The one year mortality of cases with the restricted set of codes was 29.1% but for 'stroke annual review,' 4.6% and for 'stroke monitoring codes', 5.7%. CONCLUSION: In the analysis of electronic patient records, different medical codes for a single condition may have varying clinical and prognostic significance; utilisation of different medical codes may change over time; researchers with differing clinical or epidemiological experience may have differing interpretations of the relevance of particular codes. There is a need for greater transparency in the selection of sets of codes for different conditions, for the reporting of sensitivity analyses using different sets of codes, as well as sharing of code sets among researchers.

Onset of puberty and cardiovascular risk factors in untreated obese children and adolescents: a 1-year follow-up study.

OBJECTIVE: To determine the course of obesity-associated nonalcoholic fatty liver disease (NAFLD) and the cardiovascular risk factors of hypertension, dyslipidemia, and disturbed glucose metabolism in untreated obese children. DESIGN: Obese children were examined prospectively at baseline and 1 year later. SETTING: Obesity clinic. PARTICIPANTS: A total of 287 untreated obese children; 53.3% were girls, the mean age was 11.4 years, and the mean body mass index (calculated as weight in kilograms divided by height in meters squared) was 28.2. MAIN OUTCOME MEASURES: Homeostasis model assessment of insulin resistance (HOMA-IR) values and prevalence of hypertension, dyslipidemia, impaired fasting glucose level, and NAFLD. RESULTS: At baseline, 20.6% of obese children had hypertension, 22.3% had dyslipidemia, 4.9% had impaired fasting glucose levels, and 29.3% had NAFLD. These prevalences, as well as weight status, remained stable at the 1-year follow-up visit. Increases (SDs) in prevalence of hypertension (16.1% [51.8%]), hypertriglyceridemia (9.7% [59.3%]), and impaired fasting glucose level (8.1% [32.9%]), as well as mean HOMA-IR value (0.42 [1.22]), were observed in 62 children entering puberty. In contrast, mean decreases (SDs) in hypertension (-18.8% [53.2%]), hypertriglyceridemia (-12.5% [53.1%]), impaired fasting glucose level (-6.3% [38.1%]), and NAFLD prevalence (-18.8% [44.5%]), as well as mean HOMA-IR value (-0.83 [2.56]), were observed in 50 children entering late puberty (P < .01 for change of pubertal status in the multivariate model). Changes in HOMA-IR values were only weakly related to changes in prevalence of cardiovascular risk factors or transaminase levels (r < 0.2). CONCLUSIONS: Cardiovascular risk factors worsened at onset of puberty and improved in late puberty in obese children whose weight status did not change. The weak correlation between HOMA-IR value and cardiovascular risk factors suggests that other characteristics may affect these disorders.

Antihypertensive treatment after stroke and all-cause mortality--an analysis of the General Practitioner Research Database (GPRD).

BACKGROUND: Randomised controlled trials have shown a beneficial effect of antihypertensive treatment on stroke recurrence. The effect of antihypertensive treatment on survival and recurrence in an unselected sample of the general population, using the General Practice Research Database, was analysed. METHODS: Cox regression estimating the effect of antihypertensive treatment on survival and stroke recurrence >1 year among 44,244 first-ever strokes in the UK from 1997 to 2006 was adjusted by propensity score analysis considering gender, age, general practice, stroke year, drug prescriptions and diagnostic codes from other diseases. RESULTS: The EU standardised stroke incidence was 118 per 100,000 (95% CI = 117-120). The 90-day case fatality was 19%. By 90 days after stroke 20,147 (58%) were diagnosed as having hypertension, of whom 75% had received antihypertensive treatment after stroke. After 5 years 68% of the hypertensive stroke patients receiving antihypertensive treatment were alive, while this proportion for patients not prescribed antihypertensive treatment was 59%. This could not be explained by potential confounders with an adjusted relative risk of 0.62 (95% CI = 0.58-0.66; p < 0.001) for antihypertensive treatment and premature death. The adjusted relative risk of antihypertensive treatment on stroke recurrence after 1 year, which was observed in 35% until 5 years after stroke, was 0.92 (95% CI = 0.84-1.01; p = 0.092). CONCLUSIONS: A high proportion of hypertensive stroke patients did not receive antihypertensive treatment. The protective effect of antihypertensive treatment on survival was higher in this general population than reported in randomised controlled trials, while an effect of antihypertensive treatment on late stroke recurrence was borderline, but not significant.

Lifestyle intervention in obese children is associated with a decrease of the metabolic syndrome prevalence.

BACKGROUND: Weight loss is the appropriate approach to reduce the obesity-related health risk. However, the effect of lifestyle interventions on the metabolic syndrome prevalence has been rarely studied in obese children. METHODS: We analyzed changes of weight status, 2h glucose levels from oral glucose tolerance tests (oGTT), fasting glucose, lipids, blood pressure, and the prevalence of metabolic syndrome in relation to a 1-year outpatient lifestyle intervention in 288 obese children (45% male; mean age 12.5 years, mean SDS-BMI 2.48). These data were compared to 186 obese children without intervention with similar distributions of age, gender, and weight status. RESULTS: Lifestyle intervention led to a significant decrease of SDS-BMI (mean -0.22; 95%CI -0.18 to -0.26), while SDS-BMI increased significantly in children without intervention (mean +0.15; 95%CI +0.13 to +0.18). Children with lifestyle intervention had a significant decrease of metabolic syndrome prevalence (from 19% to 9%; definition according to IDF) and an improvement of waist circumference, blood pressure, and 2h glucose values in the oGTT in contrast to obese children without intervention. The degree of weight loss was significantly associated with the amount of improvement of the components of the metabolic syndrome. Particularly, the children with a SDS-BMI reduction >0.5 showed an improvement of all components of the metabolic syndrome. CONCLUSIONS: Lifestyle intervention led to weight loss and an improvement of the metabolic syndrome and its components. Degree of weight loss was associated with the improvement of the prevalence of metabolic syndrome and its components.

Promotion and provision of drinking water in schools for overweight prevention: randomized, controlled cluster trial.

OBJECTIVE: The study tested whether a combined environmental and educational intervention solely promoting water consumption was effective in preventing overweight among children in elementary school. METHODS: The participants in this randomized, controlled cluster trial were second- and third-graders from 32 elementary schools in socially deprived areas of 2 German cities. Water fountains were installed and teachers presented 4 prepared classroom lessons in the intervention group schools (N = 17) to promote water consumption. Control group schools (N = 15) did not receive any intervention. The prevalence of overweight (defined according to the International Obesity Task Force criteria), BMI SD scores, and beverage consumption (in glasses per day; 1 glass was defined as 200 mL) self-reported in 24-hour recall questionnaires, were determined before (baseline) and after the intervention. In addition, the water flow of the fountains was measured during the intervention period of 1 school year (August 2006 to June 2007). RESULTS: Data on 2950 children (intervention group: N = 1641; control group: N = 1309; age, mean +/- SD: 8.3 +/- 0.7 years) were analyzed. After the intervention, the risk of overweight was reduced by 31% in the intervention group, compared with the control group, with adjustment for baseline prevalence of overweight and clustering according to school. Changes in BMI SD scores did not differ between the intervention group and the control group. Water consumption after the intervention was 1.1 glasses per day greater in the intervention group. No intervention effect on juice and soft drink consumption was found. Daily water flow of the fountains indicated lasting use during the entire intervention period, but to varying extent. CONCLUSION: Our environmental and educational, school-based intervention proved to be effective in the prevention of overweight among children in elementary school, even in a population from socially deprived areas.

Parental diabetes, pubertal stage, and extreme obesity are the main risk factors for prediabetes in children and adolescents: a simple risk score to identify children at risk for prediabetes.

OBJECTIVES: The current worldwide increase of prediabetes defined as impaired fasting glucose or impaired glucose tolerance and type 2 diabetes mellitus (T2DM) coincides the increase of obesity. However, it is unclear that which children have an increased risk and should be screened for prediabetes. METHODS: We studied 437 overweight children and adolescents to identify risk factors for prediabetes. A risk score for prediabetes was calculated using logistic regression. This score was examined in a second, independent cohort of 567 overweight children and adolescents. History of T2DM in parents and grandparents, degree of overweight, age, pubertal stage, birth weight, hypertension, dyslipidemia, acanthosis nigricans, and abdominal obesity were considered as potential risk factors. RESULTS: The frequency of prediabetes was 6% in sample 1 and 17% in sample 2. The strongest association was observed for history of parental diabetes with an adjusted odds ratio (aOR) of 9.5 [95% confidence interval (CI) 2.5-36.4] in sample 1 and 6.3 (95% CI 3.7-10.7) in sample 2, followed by pubertal stage with an aOR of 5.5 (95% CI 0.7-45.4) in sample 1 and 6.2 (95% CI 2.4-15.6) in sample 2, and by extreme obesity with an aOR of 5.0 (95% CI 1.7-15.3) in sample 1 and 3.3 (95% CI 2.0-5.4) in sample 2. CONCLUSIONS: The main risk factors for prediabetes were parental diabetes, pubertal stage, and extreme obesity. Screening for prediabetes seems meaningful in subjects with either a parental history of diabetes or a combination of extreme obesity and pubertal stage and detected nearly 90% of the overweight children and adolescents with prediabetes.

An illustration of and programs estimating attributable fractions in large scale surveys considering multiple risk factors.

BACKGROUND: Attributable fractions (AF) assess the proportion of cases in a population attributable to certain risk factors but are infrequently reported and mostly calculated without considering potential confounders. While logistic regression for adjusted individual estimates of odds ratios (OR) is widely used, similar approaches for AFs are rarely applied. METHODS: Different methods for calculating adjusted AFs to risk factors of cardiovascular disease (CVD) were applied using data from the National Health and Nutrition Examination Survey (NHANES). We compared AFs from the unadjusted approach using Levin's formula, from Levin's formula using adjusted OR estimates, from logistic regression according to Bruzzi's approach, from logistic regression with sequential removal of risk factors ('sequential AF') and from logistic regression with all possible removal sequences and subsequent averaging ('average AF'). RESULTS: AFs following the unadjusted and adjusted (using adjusted ORs) Levin's approach yielded clearly higher estimates with a total sum of more than 100% compared to adjusted approaches with sums < 100%. Since AFs from logistic regression were related to the removal sequence of risk factors, all possible sequences were considered and estimates were averaged. These average AFs yielded plausible estimates of the population impact of considered risk factors on CVD with a total sum of 90%. The average AFs for total and HDL cholesterol levels were 17%, for hypertension 16%, for smoking 11%, and for diabetes 5%. CONCLUSION: Average AFs provide plausible estimates of population attributable risks and should therefore be reported at least to supplement unadjusted estimates. We provide functions/macros for commonly used statistical programs to encourage other researchers to calculate and report average AFs.

Small for gestational age status is associated with metabolic syndrome in overweight children.

OBJECTIVE: Small for gestational age (SGA) children are at risk of both later obesity and metabolic syndrome (MetS). However, it is unknown whether obesity or SGA status leads to MetS in these subjects. We hypothesized that overweight children with former SGA status had more present components of the MetS than overweight children with former appropriate for gestational age (AGA) status. METHODS: We analyzed 803 overweight children (4% SGA, mean age 11+/-0.1 years, body mass index (BMI) 27.3+/-0.2, SDS-BMI 2.32+/-0.02) concerning blood pressure, lipids, glucose, and insulin. Oral glucose tolerance tests (oGTT) were performed in all 35 former SGA children and 147 randomly chosen former non-SGA children. RESULTS: After adjustment for age, sex, pubertal stage, and BMI-SDS, former SGA status was significantly related to blood pressure, triglyceride, insulin, and 2 h glucose levels in oGTT. The MetS prevalence was more than doubled in overweight former SGA subjects (40% MetS) compared with overweight former AGA subjects (17% MetS). The corresponding adjusted odds ratio was 4.08 (95% confidence interval 1.48 to 11.22) for SGA compared with AGA children. CONCLUSIONS: Overweight former SGA children had an increased risk for the components of the MetS compared with overweight former AGA children. Therefore, SGA status seems to be a risk factor for the MetS independently of weight status. Particularly overweight children with former SGA status should be screened for the MetS.

Ethnic group disparities in 10-year trends in stroke incidence and vascular risk factors: the South London Stroke Register (SLSR).

BACKGROUND AND PURPOSE: Data monitoring trends in stroke risk among different ethnic groups are lacking. Thus, we investigated trends in stroke incidence and modifiable stroke risk factors over a 10-year time period between different ethnic groups. METHODS: Changes in stroke incidence were investigated with the South London Stroke Register (SLSR). The SLSR is a population-based stroke register, covering a multiethnic population of 271 817 inhabitants in South London with 63% white, 28% black, and 9% of other ethnic group (2001 Census). RESULTS: Between 1995 and 2004, 2874 patients with first-ever stroke of all age groups were included. Total stroke incidence decreased over the 10-year study period in men (incidence rate ratio 1995 to 1996 versus 2003 to 2004 [IRR] 0.82, 95% CI 0.69 to 0.97) and in women (IRR 0.76, 95% CI 0.64 to 0.90). A similar decline in total stroke incidence could be observed in whites for men and women (IRR 0.76, 95% CI 0.62 to 0.93 versus IRR 0.73, 95% CI 0.59 to 0.89, respectively); in blacks, total stroke incidence was reducing only in women (IRR 0.48, 95% CI 0.31 to 0.75). In whites, the prevalence of prior-to-stroke hypertension (P=0.0017), atrial fibrillation (P=0.0113), and smoking (P=0.0177) decreased; no statistically significant changes in prior-to-stroke risk factors were observed in blacks. Total stroke incidence was higher in blacks compared to whites (IRR 1.27, 95% CI 1.10 to 1.46 in men; IRR 1.29, 95% CI 1.11 to 1.50 in women), but the black-white gap reduced during the 10-year time period (IRR 1.43, 95% CI 1.13 to 1.82 in 1995 to 1996 to 1.18, 95% CI 0.93 to 1.49 in 2003 to 2004). CONCLUSIONS: Stroke incidence decreased over a 10-year time period. The greatest decline in incidence was observed in black women, but ethnic group disparities still exist, indicating a higher stroke risk in black people compared to white people. Advances in risk factor reduction observed in the white population were failed transferring to the black population.

Different anthropometric index changes in relation to cardiovascular risk profile change.

BACKGROUND & AIMS: Different anthropometric indices were proposed to assess adiposity and its change in overweight children. The aim of this study was to identify the anthropometric index change that correlates best with cardiovascular risk factor change. METHODS: Lipids, insulin, blood pressure, body mass index (BMI), and skinfolds were measured among 434 overweight singletons aged 4-16 years participating and not participating in an intervention program at baseline and 1 year later from 1999 to 2005. RESULTS: Mean BMI at baseline was 27.2 kg/m(2) (standard error (SE) 0.2). A mean change at 1 year could be observed for weight (+5 kg; SE 0.32), BMI in standard deviation scores (SDS-BMI) (-0.2; SE 0.02), and relative BMI (-0.7; SE 0.1). Eighteen percent of the children reduced their SDS-BMI> or =0.5, while 34% demonstrated an increase of SDS-BMI. The prediction of insulin-, insulin resistance index- and blood pressure changes by anthropometric differences ranged from 2% to 7% adjusted variance explained, and for changes of lipids<1%. Estimated %fat from skinfolds failed as a predictor. Goodness of prediction did not differ across the other anthropometric changes. CONCLUSIONS: No superior anthropometric predictor for the limited prediction of cardiovascular risk changes was observed among the considered parameters. Cardiovascular risk factors should be tracked to prove a cardiovascular effect of weight change and/or intervention.

No temporal association between influenza outbreaks and invasive pneumococcal infections.

OBJECTIVE: To assess whether the influenza peak in populations precedes the annual peak for invasive pneumococcal infections (IPI) in winter. DESIGN: Ecological study. Active surveillance data on influenza A and IPI in children up to 16 years of age collected from 1997 to 2003 were analysed. SETTING: Paediatric hospitals in Germany. PATIENTS: Children under 16 years of age. RESULTS: In all years under study, the influenza A season did not appear to affect the IPI season (p = 0.49). Specifically, the influenza peak never preceded the IPI peak. CONCLUSION: On a population level there was no indication that the annual influenza epidemic triggered the winter increase in the IPI rate or the peak of the IPI distribution in children.