Sandra Plachta-Danielzik

Quercetin reduces systolic blood pressure and plasma oxidised low-density lipoprotein concentrations in overweight subjects with a high-cardiovascular disease risk phenotype: a double-blinded, placebo-controlled cross-over study

Regular consumption of flavonoids may reduce the risk for CVD. However, the effects of individual flavonoids, for example, quercetin, remain unclear. The present study was undertaken to examine the effects of quercetin supplementation on blood pressure, lipid metabolism, markers of oxidative stress, inflammation, and body composition in an at-risk population of ninety-three overweight or obese subjects aged 25-65 years with metabolic syndrome traits. Subjects were randomised to receive 150 mg quercetin/d in a double-blinded, placebo-controlled cross-over trial with 6-week treatment periods separated by a 5-week washout period. Mean fasting plasma quercetin concentrations increased from 71 to 269 nmol/l (P < 0.001) during quercetin treatment. In contrast to placebo, quercetin decreased systolic blood pressure (SBP) by 2.6 mmHg (P < 0.01) in the entire study group, by 2.9 mmHg (P < 0.01) in the subgroup of hypertensive subjects and by 3.7 mmHg (P < 0.001) in the subgroup of younger adults aged 25-50 years. Quercetin decreased serum HDL-cholesterol concentrations (P < 0.001), while total cholesterol, TAG and the LDL:HDL-cholesterol and TAG:HDL-cholesterol ratios were unaltered. Quercetin significantly decreased plasma concentrations of atherogenic oxidised LDL, but did not affect TNF-alpha and C-reactive protein when compared with placebo. Quercetin supplementation had no effects on nutritional status. Blood parameters of liver and kidney function, haematology and serum electrolytes did not reveal any adverse effects of quercetin. In conclusion, quercetin reduced SBP and plasma oxidised LDL concentrations in overweight subjects with a high-CVD risk phenotype. Our findings provide further evidence that quercetin may provide protection against CVD.

Determinants and impact of sleep duration in children and adolescents: data of the Kiel Obesity Prevention Study.

Background/Objectives: This study investigates determinants of sleep duration and its impact on nutritional status, resting energy expenditure (REE), cardiometabolic risk factors and hormones in children/adolescents.Subjects/Methods: In 207 girls and 207 boys (13.0±3.4 (6.1–19.9) years) body mass index standard deviation score (BMI SDS), waist circumference (WC) z-score, body composition (air-displacement plethysmography), REE (ventilated hood system; n=312) and cardiometabolic risk factors/hormones (n=250) were assessed. Greater than 90th percentile of BMI/WC references was defined as overweight/overwaist. Sleep duration, media consumption (TV watching/computer use), physical activity, dietary habits, parental BMI, socio-economic status and early infancy were assessed by questionnaire. Short sleep was defined as <10 h per day for children <10 years and otherwise <9 h per day.Results: Total 15.9% participants were overweight, mean sleep duration was 8.9±1.3 h per day. Age explained most variance in sleep (girls: 57.0%; boys: 41.2%) besides a high nutrition quality score (girls: 0.9%) and a low media consumption (boys: 1.3%). Sleep was inversely associated with BMI SDS/WC z-score (girls: r=−0.17/−0.19, P<0.05; boys: r=−0.21/−0.20, P<0.01), which was strengthened after adjusting for confounders. Short vs long sleep was associated with 5.5-/2.3-fold higher risks for obesity/overwaist (girls). After adjusting for age, REE (adjusted for fat-free mass) was positively associated with sleep in boys (r=0.16, P<0.05). Independently of age and WC z-score, short sleep was associated with lower adiponectin levels in boys (11.7 vs 14.4 μg/ml, P<0.05); leptin levels were inversely related to sleep in girls (r=−0.23, P<0.05). Homoeostasis model assessment–insulin resistance (r=−0.20, P<0.05) and insulin levels (r=−0.20, P<0.05) were associated with sleep (girls), which depended on WC z-score.Conclusions: Age mostly determined sleep. Short sleep was related to a higher BMI SDS/WC z-score (girls/boys), a lower REE (boys), higher leptin (girls) and lower adiponectin levels (boys).

Four-year follow-up of school-based intervention on overweight children: the KOPS study.

Objective: To evaluate the 4‐year outcome of a school‐based health promotion on weight status as part of the Kiel Obesity Prevention Study (KOPS).

Associations between active commuting to school, fat mass and lifestyle factors in adolescents: the Kiel Obesity Prevention Study (KOPS)

Objective:To examine possible associations between active commuting (walking or cycling) to school, parameters of adiposity and lifestyle factors in 14-year-old adolescents of the Kiel Obesity Prevention Study.Subjects:A total of 626 14-year-old adolescents.Methods:Measured body mass index (BMI), fat mass (FM), distance to school as well as self-reported modes and duration of commuting to school, time spent in structured and unstructured physical activities (PAs), media use, nutrition, alcohol consumption and smoking.Results:Parameters of adiposity did not differ between different commuting modes after stratifying by gender. Active commuters reported higher overall PA, which was caused by commuting activity and time spent in unstructured PA in girls and just by commuting activity in boys. In active commuters, 28.4% of overall PA was explained by commuting activity. Additionally, TV viewing was lower in active commuters. Compared to their inactively commuting counterparts, actively commuting boys were less likely to smoke. After controlling for potential confounders the interaction term ‘active commuting by distance to school’ and ‘time spent in structured PA’ were independent predictors of FM, whereas active commuting by itself showed no effect.Conclusion:The present data suggest that active commuting to school per se does not affect FM or BMI until considering distance to school. Increasing walking or cycling distance results in decreasing FM. However, the everyday need to get to and from school may enhance adolescents’ overall PA.

Association of different obesity indices with blood pressure and blood lipids in children and adolescents.

The aim of the present study was to compare individual associations of BMI, triceps skinfold (TSF), waist circumference (WC) and percentage fat mass (%FM) with blood pressure (BP) and blood lipids in children and adolescents. Cross-sectional data on BMI, TSF, WC, %FM as well as on BP, TAG and HDL were analysed in 4220 (BP) and 729 (lipids) 9-11-year-old children and 3174 (BP) and 536 (lipids) 13-16-year-old adolescents as part of the Kiel Obesity Prevention Study. All obesity indices were similarly associated with BP and blood lipids. In girls, WC had closer correlations to BP than BMI (systolic BP: 0.27 and 0.24 for BMI, 0.34 and 0.28 for WC in 9-11- and 13-16-year-olds). Subjects with an obesity index > or = 90th percentile had higher prevalences of elevated BP and blood lipids than subjects with a normal index. In children with normal BMI or WC, an additionally elevated second obesity index was associated with a 2.5-7.4-fold higher prevalence of high BP when compared with children with normal indices. In adolescents, an elevated WC plus an elevated second obesity index was associated with a 2.6-8.2-fold higher prevalence of high BP when compared with adolescents with an elevated WC plus a normal second index. We conclude that (i) both BMI and WC are appropriate to estimate CVD risk, (ii) the use of a second obesity index is recommended in children with normal BMI or normal WC as well as in adolescents with elevated WC and (iii) all obesity indices seemed to be appropriate for risk assessment.

Energy gain and energy gap in normal-weight children: longitudinal data of the KOPS.

Population‐based prevention of overweight needs evidence‐based goals consistent with our present knowledge about energy gap (i.e., daily imbalance between energy intake and energy expenditure resulting in overweight). Longitudinal data of normal‐weight children (1,029 girls and 1,028 boys; Kiel Obesity Prevention Study, KOPS) were used to calculate energy gain (i.e., increase in fat mass (FM) and fat‐free mass (FFM)) in normal‐weight children staying normal weight (persistent children) or becoming overweight (incident children). Taking into account weight gain in proportion to height gain (normal development) energy gap was calculated from increases in FM and FFM exceeding normal development. Children were divided into two groups and were followed from age 6 to 10 (group A) and 10 to 14 years (group B). FM and FFM were measured. Medians of 4‐year BMI‐ (kg/m2)/weight changes (kg) were +1.8/+13.2 (A) and +3.0/+18.7 (B) in girls, and +1.6/+12.8 (A) and +2.6/21.7 (B) in boys. Corresponding data for FM/FFM (kg) were +3.1/+10.2 (A) and +5.1/12.7 (B) in girls, and +2.3/10.8 (A) and +3.0/18.6 (B) in boys. The 4‐year‐incidence of overweight (%) were 9.4 (A) and 5.4 (B) in girls, and 11.0 (A) and 3.8 (B) in boys, respectively. Mean energy gains (kcal/day) were 26.8 (A) and 46.4 (B) in girls, and 22.1 (A) and 32.5 (B) in boys. The 90th percentile of energy gap (kcal/day) in incident children were 58.1 (A) and 72.0 (B) in girls and 46.0 (A) and 53.2 (B) in boys. To prevent overweight in children energy gap should not exceed 46–72 kcal/day.

Short stature and obesity: positive association in adults but inverse association in children and adolescents.

Shorter than average adults are at a higher risk for obesity and are also more susceptible to diabetes and CVD, independent of BMI. In contrast, taller children have a higher risk of obesity. We hypothesised that short stature is related to adverse body composition and that the association between stature and obesity differs between generations. In a cross-sectional German database of 213 804 adults and 12 411 children and adolescents, the prevalence of overweight and obesity was compared between percentiles of height. The association between stature and percentage of fat mass (%FM), lean BMI (LBMI; kg/m2) or waist:hip ratio (in children only) was analysed within BMI groups. In adults, the prevalence of BMI >30 kg/m2 gradually increased with decreasing percentile of height whereas in children and adolescents, a positive association between height and weight status was observed. Short-stature women and girls had a 0.8-3.2 % lower %FM than tall subjects (P < 0.05), whereas no trend for %FM was observed in males. When compared with tall subjects, LBMI was 0.2-0.6 kg/m2 lower in short-stature men, as well as obese women (P < 0.05). There was a non-significant trend for a lower LBMI and a higher waist:hip ratio in shorter children. In conclusion, short stature is associated with an increased risk of obesity in adults. Cardiometabolic risk in short stature is not explained by an adverse body composition.

Eight-year follow-up of school-based intervention on childhood overweight--the Kiel Obesity Prevention Study.

Objective: The aim of this study was to evaluate the 8-year outcome of school-based intervention on weight status, lifestyle and blood pressure (BP) as part of the Kiel Obesity Prevention Study (KOPS). Methods: Within a quasi-randomized controlled trial, 240 intervention (I) and 952 non-intervention (NI) students at age 6 and 14 years were assessed in schools. Six nutrition units followed by 20-min running games were performed within the first year at school. Primary outcome was the 8-year change in body mass index standard deviation score (BMI-SDS) according to German references. Effective intervention was tested using multilevel linear regression analysis. Results: Eight-year changes in BMISDS were +0.18 and +0.22 with increases in prevalence of overweight from 8.3 to 10.4% and 7.0 to 11.2% in I and NI students, respectively. Cumulative 8-year incidence of overweight was 5.9% and 7.1% in I and NI students, respectively. There was no overall effect of intervention, but a significant interaction was shown between the intervention and the socio-economic status (SES), which demonstrated that in high SES, the 8-year change in BMI-SDS was in favour of I (–0.17 in I and +0.17 in NI; p < 0.01). Intervention had no measurable effects on lifestyle and BP. Conclusions: School-based health promotion has some favourable and sustained effects on 8-year changes in BMI-SDS, which are most pronounced in students of high SES families. The data argue in favour of further preventive measures.

Determinants of the prevalence and incidence of overweight in children and adolescents

OBJECTIVE To systematically analyse determinants of overweight prevalence and incidence in children and adolescents, as a basis of treatment and prevention. DESIGN Cross-sectional and longitudinal data of the Kiel Obesity Prevention Study (KOPS). SETTING Schools in Kiel, Germany. SUBJECTS Cross-sectional data from 6249 students aged 5-16 years and 4-year longitudinal data from 1087 children aged 5-11 years. Weight status of students was assessed and familial factors (weight status of parents and siblings, smoking habits), social factors (socio-economic status, nationality, single parenting), birth weight as well as lifestyle variables (physical activity, media time, nutrition) were considered as independent variables in multivariate logistic regression analyses to predict the likelihood of the student being overweight. RESULTS The cross-sectional data revealed the prevalence of overweight as 18·3 % in boys and 19·2 % in girls. In both sexes determinants of overweight prevalence were overweight and obese parents, overweight siblings, parental smoking, single parenthood and non-German nationality. High birth weight and low physical activity additionally increased the risk in boys. High media time and low parental education were significant determinants in girls. Effect of media time was mediated by maternal weight status in boys as well as by socio-economic status and age in girls. From the longitudinal data, the 4-year cumulative incidence of overweight was 10·0 % in boys and 8·2 % in girls. Parental obesity, parental smoking and low physical activity were determinants of overweight incidence in boys, whereas paternal obesity increased the risk in girls. CONCLUSIONS Treatment and prevention should address family and social determinants with a focus on physical activity and media use.

Gestational weight gain and body mass index in children: results from three german cohort studies.

Introduction Previous studies suggested potential priming effects of gestational weight gain (GWG) on offspring’s body composition in later life. However, consistency of these effects in normal weight, overweight and obese mothers is less clear. Methods We combined the individual data of three German cohorts and assessed associations of total and excessive GWG (as defined by criteria of the Institute of Medicine) with offspring’s mean body mass index (BMI) standard deviation scores (SDS) and overweight at the age of 5–6 years (total: n = 6,254). Quantile regression was used to examine potentially different effects on different parts of the BMI SDS distribution. All models were adjusted for birth weight, maternal age and maternal smoking during pregnancy and stratified by maternal pre-pregnancy weight status. Results In adjusted models, positive associations of total and excessive GWG with mean BMI SDS and overweight were observed only in children of non- overweight mothers. For example, excessive GWG was associated with a mean increase of 0.08 (95% CI: 0.01, 0.15) units of BMI SDS (0.13 (0.02, 0.24) kg/m2 of ‘real’ BMI) in children of normal-weight mothers. The effects of total and excessive GWG on BMI SDS increased for higher- BMI children of normal-weight mothers. Discussion Increased GWG is likely to be associated with overweight in offspring of non-overweight mothers.