KiGGS Study Research Articles

Allergy and school: nothing to be sneezed at!: A primary school project in Bielefeld, Germany, on epidemiology and health promotion in allergic diseases.

Background:Allergic diseases account for the largest proportion of chronic diseases in childhood and adolescence and place a significant burden on everyday family, social, and in particular school life. Without appropriate education, affected individuals often have little of the knowledge required to understand and deal safely with their allergic disease, and their social environment (school) generally offers insufficient information. An interdisciplinary project involving the Bielefeld Community Foundation (“Bielefelder Bürgerstiftung”), the Children’s Center Bethel, and the local school authority investigated the current knowledge, possibilities for increasing that knowledge, as well as pupils’ and teachers’ perception of the problems experienced by fellow pupils, while at the same time collecting current prevalence figures on allergic diseases among primary school children.Methods:All Bielefeld primary schools were invited to participate in the 3 years between 2008 and 2010. A teaching session on allergic diseases held by specialists from the pediatric hospital formed the core of the project. A standardized survey of children – which also addressed non-affected children for the first time in Germany – on the effects of, their knowledge of, and their attitudes toward allergic diseases, as well as an assessment of their quality of life (cross-sectional study), was conducted prior to and following each session. Parents were also surveyed.Results:In all, 24 schools per year, each with around 60 classes and 1,250 pupils aged 9 years, took part between 2008 and 2010. Approximately 30 % reported suffering from an allergic disease themselves, of which – with regard to single entries – 16 % were “allergies,” 4 % “asthma,” and 5 % atopic dermatitis. Figures collected from parents were only slightly lower than those from their children. Clear deficits that existed in terms of factual knowledge and/or correct conduct in allergic disease – among affected children as well as in their social environment – prior to the education program were noticeably improved by the teaching session.Discussion:The prevalence data gathered here confirm the high numbers recently found in the KiGGS study. Thus, allergic diseases represent a considerable disease risk and potential burden in school children. Providing affected children and their social environment (teachers, fellow pupils) with specialist education can bring about considerable improvements in everyday school life.

Social determinants of maternal smoking during pregnancy: findings from the German KiGGS study

Social determinants of maternal smoking during pregnancy: findings from the German KiGGS study

New reference centiles for boys' height, weight and body mass index used voice break as the marker of biological age.

We aimed to develop the first references for body height, body weight and body mass index (BMI) for boys based on the individual developmental tempo with respect to their voice break status. We re-analysed data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS study) on body height, body weight and body mass index based on the voice break, or mutation, in 3956 boys aged 10-17 years. We used the LMS method to construct smoothed references centiles for the studied variables in premutational, mutational and postmutational boys. Body height, body weight and BMI differed significantly (p < 0.001) between the different stages of voice break. On average, boys were 5.9 cm taller, 5.8 kg heavier and had a 0.7 kg/m² higher BMI with every higher stage of voice break. Currently used growth references for chronological age in comparison with maturity-related references led to an average of 5.4% of boys being falsely classified as overweight. These newly developed growth references allowed convenient classifications of underweight and overweight or obese boys with respect to their voice break status. They should be added to currently used references centiles for the body mass index to avoid misclassifying boys' weight.

Pediatric reference data of serum lipids and prevalence of dyslipidemia: Results from a population-based cohort in Germany

BackgroundSerum lipid concentrations are thought to be risk factors for the development of cardiovascular disease. The present study aims to investigate the prevalence of dyslipidemia and provide sex- and age-related reference values for triglycerides, total cholesterol, LDL and HDL cholesterol as well as apolipoproteins A1 and B by using modern analytical approaches. Materials and methodsVenous blood and anthropometric data were collected from 2571 subjects of the LIFE Child study, aged between 0.5 and 16years. Age- and gender-related reference intervals (3rd and 97th percentiles) were established by using Cole's LMS method. ResultsSerum concentrations of TC, LDL-C, TG and ApoB were higher in girls than in boys. In girls TC reached peak levels two years earlier than in boys. Triglyceride levels initially declined until the school age. Until early adolescence there was a steady increase. The LDL-C concentrations in girls and boys followed similar patterns to that of TC. Up to the age of 8years, a continuous increase in HDL levels for both sexes was found. Due to the strong correlation between HDL-C and ApoA1 (r=0.87) or rather between LDL-C and ApoB (r=0.93), the respective percentiles showed very similar patterns. Dyslipidemia prevalence were as follows: increased TC 7.8%, increased LDL 6.1%, increased TG 0–9years 22.1%, increased TG 10–16years 11.7%, and decreased HDL 8.0%. ConclusionAge- and sex-related trends for all parameters are similar to those of the German KIGGS study. With the exception of HDL cholesterol, the prevalence of dyslipidemias in the German LIFE Child cohort are similar to the US-American prevalence.

Nationwide Survey on the Health of Offspring from Former Childhood Cancer Patients in Germany.

Increased risk for infertility from cancer treatment and fear of health impairment in their offspring may prevent survivors of childhood cancer from having own children. Even though most studies report no increased risk for malformations, in our German fertility study 2008 a higher occurrence of cleft lip and palate was found in offspring of former patients. Since 2010 we assess offspring's health in a survey-based multicenter study, comparing diseases, well-being, healthcare utilization and health-related behavior between offspring from survivors, siblings or the general population. Within a first nationwide survey wave survivors who were known to have at least one child by previous fertility studies, received a questionnaire supported by the German Childhood Cancer Registry. Questionnaires were based on the KiGGS study on children's health in the German general population conducted by the Robert-Koch Institute (n=17,641). Questionnaires on 418 children were answered by 65% (254/393) of survivors contacted to participate in the first nationwide offspring study wave. Participants were more likely to be female (p<0.01), to have achieved higher educational levels (p<0.05) and to be a survivor of a soft tissue tumor (p<0.05). Former patients expressed moderate to high anxiety for the occurrence of cancer in 74% and feared other diseases in their children in 20%. Offspring health is a topic of major relevance to former patients. Our offspring study is currently being extended to ~1500 offspring of childhood cancer survivors in Europe.

Examination of iodine status in the German population: an example for methodological pitfalls of the current approach of iodine status assessment.

Preliminary iodine concentration (UIC) measurements in spot urines of the representative German adult study DEGS indicated a severe worsening of iodine status compared to previous results in German children (KiGGS study). Therefore, we aimed to evaluate adult iodine status in detail and to investigate the impact of hydration status on UIC. UIC and creatinine concentrations were measured in 6978 spot urines from the German nationwide DEGS study (2008-2011). Twenty-four-hour iodine excretions (24-h UIE) were estimated by relating iodine/creatinine ratios to age- and sex-specific 24-h creatinine reference values. Urine osmolality was measured in two subsamples of spot urines (n = 100 each) to determine the impact of hydration status on UIC. In DEGS, median UIC was 69 µg/L in men and 54 µg/L in women, lying clearly below the WHO cutoff for iodine sufficiency (100 µg/L). Estimated median 24-h UIE was 113 µg/day, accompanied by 32 % of DEGS adults, lying below the estimated average requirement (EAR) for iodine. Comparative analysis with the KiGGS data (>14,000 spot urines of children; median UIC 117 µg/L) revealed a comparable percentage <EAR (33 %). In two DEGS subsamples with significantly different UIC but similar median 24-h UIE, osmolality was twofold higher in the high- versus the low-UIC group. Over 30 % of participants in the two German surveys had an estimated iodine intake less than the respective age-group-specific EAR. Our data strongly suggest that even in large surveys, hydration status can considerably interfere with the epidemiological iodine assessment parameter UIC. The present data can serve as an example how to evaluate population-based spot urine data on a 24-h basis, independent of hydration status.

Length and weight of very low birth weight infants in Germany at 2 years of age: does it matter at what age they start complementary food?

We analysed at what age parents start complementary food in very low birth weight infants, determined risk factors for early introduction of complementary food (post-term age) and analysed whether the age at introduction of complementary food influences height or weight at 2 years of age. Parents of premature infants born in 2009-2011 answered questionnaires regarding introduction of complementary food in the first year of life (N=2262) and were followed up at a post-term age of 2 years (N=981). Length and weight were compared with full-term infants from the KiGGs study. Logistic and linear regression analyses were conducted to study predictors for early introduction of complementary food and the influence of age at introduction of complementary food on later height and weight. Average age at introduction of complementary food was 3.5 months post-term age. The lower the gestational age at birth, the earlier (post-term age) vegetables and meat were introduced. Age at introduction of complementary food was influenced by intrauterine growth restriction, gestational age at birth, maternal education and a developmental delay perceived by the parents. Length and weight at a post-term age of 2 years was not negatively influenced by early introduction of complementary food. VLBW infants are introduced to complementary food on average before a post-term age of 4 months. There was no negative effect of early introduction of complementary food on height and weight at 2 years of age.

Does breastfeeding help to reduce the risk of childhood overweight and obesity? A propensity score analysis of data from the KiGGS study.

BackgroundCurrent studies suggest that the beneficial effect of breastfeeding on overweight and obesity may have been largely overestimated. We examined the relationship between >4 months of full breastfeeding and overweight/obesity in children living in Germany.MethodsWe analyzed retrospectively collected data on breastfeeding from children aged 3–17 years who participated in the German Health Interview and Examination Survey for Children and Adolescents (KiGGS baseline study) between 2003 and 2006 (n = 13163). To minimize confounding, we applied propensity score matching and multivariate logistic regression analyses to estimate the effect of breastfeeding on childhood overweight and obesity.ResultsAdjusted analyses of the matched dataset (n = 8034) indicated that children who were breastfed for <4 months had a significant reduction in the odds of overweight (OR 0.81 [95% CI 0.71–0.92]) and obesity (OR 0.75 [95% CI 0.61–0.92]) compared to children who were not breastfed or who were breastfed for a shorter duration. Further analyses stratified by age group showed that the association was strongest in children aged 7–10 years (OR 0.67 [95% CI 0.53–0.84] for overweight and OR 0.56 [95% CI 0.39–0.81] for obesity), while no significant effect could be seen in other age groups.DiscussionOur findings support the hypothesis that breastfeeding does have a beneficial effect on childhood overweight and obesity, although the effect seems to be strongest in children of primary school age.

Sleep Duration and Sleep Problems in a Representative Sample of German Children and Adolescents

Objective: The main purpose of the present study was to evaluate sleep duration for nighttime sleep from early infancy to late adolescence in a German sample to illustrate the developmental course and age-specific variability of these variables among subjects. Methods: A total of 17,641 subjects from the KiGGS study were evaluated. The questionnaires contained questions about physical health, living circumstances, health behavior and risks, health supply, mental health, health-related quality of life and sleep. KiGGS assessed sleep by using parent questionnaire of children aged 0 to 10 years (n = 9944) and self-reports of adolescents (n = 7697) aged 11 to 17 years. Results: Total sleep duration decreased from 14.28 hours (SD = 2.33) at the ages 0 - 0.5 to 9.50 hours (SD = 0.82) at the ages of 10.5 - 11. Above the age of 11 adolescents report a decrease of sleep at night from 9.41 hours (SD = 1.33) at the age of 11 - 11.5 to 7.42 (SD = 1.73) at the age of 17.5 - 18 years. Unspecified sleep problems were reported of 19.5%, 13.0% of the children had difficulties falling asleep, difficulties sleeping through the night showed 8.8% of the children, whereas 3.0% report both symptoms—difficulties falling asleep and difficulties sleeping through the night. Conclusions: Age-specific variability of sleep duration is reported as well as sleep difficulties from infancy to adolescence. This is important knowledge for the health care professional who deals with sleep problems in pediatric practice.

Development and Validation of Correction Formulas for Self-Reported Height and Weight to Estimate BMI in Adolescents. Results from the KiGGS Study

Objective: The use of reported instead of measured height and weight induces a bias in prevalence rates for overweight and obesity. Therefore, correction formulas are necessary. Methods: Self-reported and measured height and weight were available from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) baseline study (2003-2006) from 3,468 adolescents aged 11-17 years. With regression analyses, correction formulas for height and weight were developed. Cross-validation was conducted in order to validate and compare the formulas. Corrected BMI was calculated, and corrected prevalence rates were estimated. Sensitivity, specificity, and predictive values for overweight and obesity were calculated. Results: Through the correction procedure, the mean differences between reported and measured height and weight become remarkably smaller and thus the estimated prevalence rates more accurate. The corrected proportions for overweight and obesity are less under-reported, while the corrected proportions for underweight are less over-reported. Sensitivity for overweight and obesity increased after correction. Specificity remained high. Conclusion: The validation process showed that the correction formulas are an appropriate tool to correct self-reports on an individual level in order to estimate corrected prevalence rates of overweight and obesity in adolescents for studies which have collected self-reports only.

Applying a correction procedure to the prevalence estimates of overweight and obesity in the German part of the HBSC study

BackgroundPrevalence rates for overweight and obesity based on self-reported height and weight are underestimated, whereas the prevalence rate for underweight is slightly overestimated. Therefore a correction is needed. Aim of this study is to apply correction procedures to the prevalence rates developed on basis of (self-reported and measured) data from the representative German National Health Interview and Examination Survey for Children and Adolescents (KiGGS) to (self-reported) data from the German Health Behaviour in School Aged Children (HBSC) study to determine whether correction leads to higher prevalence estimates of overweight and obesity as well as lower prevalence rates for underweight.MethodsBMI classifications based on self-reported and measured height and weight from a subsample of the KiGGS study (2,565 adolescents aged 11–15) were used to estimate two different correction formulas. The first and the second correction function are described. Furthermore, the both formulas were applied to the prevalence rates from the HBSC study (7,274 adolescents aged 11–15) which are based on self-reports collected via self-administered questionnaires.ResultsAfter applying the first correction function to self-reported data of the HBSC study, the prevalence rates of overweight and obesity increased from 5.5% to 7.8% (compared to 10.4% in the KiGGS study) and 2.7% to 3.8% (compared to 7.8% in the KiGGS study), respectively, whereas the corrected prevalence rates of underweight and severe underweight decreased from 8.0% to 6.7% (compared to 5.7% in the KiGGS study) and from 5.5% to 3.3% (compared to 2.4% in the KiGGS study), respectively. Application of the second correction function, which additionally considers body image, led to further slight corrections with an increase of the prevalence rates for overweight to 7.9% and for obese to 3.9%.ConclusionSubjective BMI can be used to determine the prevalence of overweight and obesity among children and adolescents. Where there is evidence of bias, the prevalence estimates should be corrected using conditional probabilities that link measured and subjectively assessed BMI from a representative validation study. These corrections may be improved further by considering body image as an additional influential factor.

Adolescents' Use of Alcohol, Tobacco and Illicit Drugs in Relation to Prenatal Alcohol Exposure: Modifications by Gender and Ethnicity

The study aimed to investigate (a) the association between low to moderate prenatal alcohol exposure (PAE) and the use of alcohol, tobacco and illicit drugs in adolescence and (b) whether the associations are modified by gender and ethnicity. The subjects of the study were 5922 children and adolescents, aged from 11 to 17 years, enrolled in the cross-sectional German Health Interview and Examination Survey for Children and Adolescents (the KiGGS study). Information on PAE is based on parental self-report questionnaires. Use of alcohol, tobacco and illicit drugs was assessed through self-report questionnaires for adolescents. Low to moderate PAE was associated with an increased risk of drinking alcohol (adjusted odds ratio (OR) 1.73, 95% confidence interval (CI) 1.34, 2.18) and also of illicit drug use (adjusted OR 1.62, 95% CI 1.23, 2.14). The associations between PAE and the use of alcohol, tobacco and illicit drugs differed according to gender and ethnicity. Gender-stratified analyses resulted in adverse effects of PAE on drinking alcohol, smoking and illicit drug use in females; however, in German males, the associations disappeared. Stronger associations between PAE and the outcome measures were found in non-Germans. Our findings indicate that low to moderate levels of maternal alcohol intake during pregnancy are a risk factor for use of alcohol, tobacco and illicit drugs by the offspring, with stronger associations in females and non-Germans.

Pulse pressure in children and adolescents with type 1 diabetes mellitus in Germany and Austria.

Impaired blood pressure regulation contributes to the development of diabetic complications. The influence of systolic (SBP) vs.diastolic blood pressure (DBP) is still controversial. Peripheral pulse pressure(PP), the difference between SBP and DBP, is an indicator for arterial stiffness. Only little data are available for PP in children. Therefore, we studied PP regulation in type 1 diabetic children and adolescents.Methods: Blood pressure values of 46 737 patients with T1DM younger than 20 years are documented in the DPV database and were compared with the control populations of the '4th report on high blood pressure (4th report)’ and the German KIGGS study. PP is increased in 63% (4th report) or 67% (KIGGS) of the patients,respectively. The rate of increased PP remains stable between 59 and 68%,irrespective of sex, age, and the control population. Absolute PP is elevated independently of the control population (PP T1DM 49.13±11.1 vs. 4th report 45.38 ± 3 vs. KIGGS 44.58 ± 4.6 mmHg; all p<0.0001, Wilcoxon test)and increases with age in both sexes. Age, male sex, diabetes duration, insulin dose, and body mass index (BMI) are independent factors contributing to elevated absolute PP levels and to the prevalence of wide PP. HbA1c is negligible negatively related to increased PP levels (multiple linear regression). In T1DM increased PP is a marker for accelerated arterial stiffness and aging and should be considered as an additional risk factor in the treatment of diabetic children. Elevated PP in children with T1DM may contribute to the high risk for early development of atherosclerosis.

Prevalence and gender patterns of mental health problems in German youth with experience of violence: the KiGGS study

BackgroundResearch examining mental health in violence-affected youth in representative samples is rare. Using data from the nationally representative German Health Interview and Examination Survey for Children and Adolescents (KiGGS) this study reports on gender-specific prevalence rates and associations of a broad range of internalizing and externalizing mental health problems: emotional problems, conduct problems, ADHD, disordered eating, somatic pain and substance use in youth variously affected by violence. While internalizing is generally more common in girls and externalizing in boys, observations of prior non-normative studies suggest reverse associations once an individual is affected by violence. The occurrence of such “gender cross-over effects” is therefore examined in a representative sample.MethodsThe sample consisted of 6,813 adolescents aged 11 to 17 from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS): Applying multivariate logistic regression analyses, associations between each type of violence history and mental health indicator were determined for perpetrators, victims, and perpetrating victims of youth violence. Moderating effects of gender were examined by using product term interaction.ResultsVictim status was associated primarily with internalizing problems, while perpetrators were more prone to externalizing problems. Perpetrating victims stood out with respect to the number and strength of risk associations with all investigated mental health indicators. However, the risk profiles of all violence-affected youth included both internalizing and externalizing mental health problems. Gender cross-over effects were found for girls and boys: despite lower overall prevalence, girls affected by violence were at far higher risk for conduct problems and illicit drug use; by contrast, somatic pain, although generally lower in males, was positively associated with perpetrator status and perpetrating victim status in boys. All violence-affected youth exhibited significantly higher rates of cumulative mental health problems.ConclusionsThe results highlight the importance of violence for the mental health of youth. They reveal a particular vulnerability as a function of gender. Implications for policy making, clinical practice and research are discussed.

„Ich mach mir keine Sorgen …!“ Wie 4- bis 8-jährige Kinder krebskranker Eltern im Berkeley Puppet Interview psychische Symptome selbst einschätzen

The Berkeley Puppet Interview (BPI) enables us to investigate psychological symptoms of children aged four to eight years under a multi-informant perspective by the means of self and parent report measures. 45 families with one parent suffering from cancer have been examined with regard to internalizing and externalizing symptoms of the children. Results have been compared to two different age-appropriate samples (Swiss preschool study of Basel and German KiGGS study). A small, highly selective sample of twelve children aged four to eight years could have been examined both from the self and parent perspective. Our results show, that four to eight year old children of cancer patients do not differ from other children of the same age in the way they express emotional symptoms in the BPI, but they are judged more emotionally burdened than other children by their parents (SDQ). Self and parent report do not significantly correlate. It seems as if parents in families struck by a cancer disease see their children's emotional symptoms more pronounced than the children themselves do express in the puppet interview. Implications for clinical and research practice will be discussed.

Abdominal Obesity in German Adolescents Defined by Waist-to-Height Ratio and Its Association to Elevated Blood Pressure: The KiGGS Study

Objective: The aim of this study was to compare the fixed 0.5 cut-off and the age- and sex-specific 90th percentile (P90) for waist-to-height ratio (WHtR) in German adolescents with respect to the prevalence of abdominal obesity and to compare the screening ability of WHtR and BMI to identify hypertensive blood pressure (BP) values. Methods: Between 2003 and 2006, the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) was carried out including 3,492 boys and 3,321 girls aged 11-17 years. Abdominal obesity was assessed by two WHtR cut-points (P90; 0.5). Hypertensive BP was defined as BP exceeding age-, sex- and height-specific 95th percentiles or the adult threshold for hypertension (140/90 mm Hg). Results: Agreement between the WHtR cut-offs was very good (Kappa 0.89 for boys; 0.81 for girls), and the prevalence of abdominal obesity was slightly higher using P90 (boys 12.0%; girls 11.3%) compared to 0.5 (boys 10.7%; girls 8.0%). WHtR and BMI-for-age had equivalent ability to discriminate hypertensive BP (ROC-AUC < 0.7; sensitivity of the 0.5 cut-off for detecting hypertensive BP < 30%). Conclusion: The fixed 0.5 WHtR cut-off can be used in German adolescents to characterize abdominal obesity. However, WHtR is not suitable as a screening tool for hypertensive BP in adolescents.

„Na? Geht's gut?“ Zum gesundheitlichen Wohlbefinden (self-rated health) von Jungen und Mädchen mit externalisierenden Verhaltensproblemen

Externalising behavior problems involve a huge developmental risk potential as they can substantially interface with the parallel process of establishing and forming identity in peer groups during adolescence while simultaneously coping with expectations regarding academic achievement and behaviour. Therefore adolescents with externalising behavior constitute a potential target audience for health promotion. The purpose of this paper is to clarify in what kind of social contexts externalising behavior problems are associated with decreased subjective health in adolescence. An analysis of secondary data from the KiGGS study (Robert Koch-Institute, 2009) was undertaken. Calculations of logistic regression models for boys and girls were performed on the basis of preceding stratifications using the indicator subjective health and including relevant social demographic factors. Externalising adolescents face a higher risk of decreased subjective health than inconspicuous adolescents of the same age group, while there is a gender-specific difference (boys OR 2.76; girls OR 1.48). The gender-specific differences in subjective health appraisal found in inconspicuous adolescents cannot be verified in adolescents with externalising behaviour. Related to social demographic predictors a classic social gradient for girls is verified whereas externalising behaviour in boys is predominantly associated from high social class and decreased subjective health. In multivariate procedures a higher odds ratio for decreased subjective health becomes apparent for adolescents who ascend or descend in relation to their education level as well as for adolescents from higher social classes who had to repeat a school year. Adolescents with externalising behavior frequently rate their health situation as being bad. The fact that it is primarily boys with behavior problems and boys who are intergenerational mobile educationwise who exhibit decreased psychosocial well-being, indicates that an increased context related exclusion risk (ostracism) is an essential health risk factor. Micro-groups of adolescents facing risk of being ostracised appear to be an essential target group for prevention and health promotion which so far is not being taken into consideration on the basis of school type related recommendations.

Overview of the study design, participation and field work of the German Environmental Survey on Children 2003–2006 (GerES IV)

The German Federal Environment Agency carried out its fourth German Environmental Survey (GerES IV), which is the first survey on children only and the environment-related module of the German Health Interview and Examination Survey for Children and Adolescents (German acronym: KiGGS), conducted by the Robert Koch Institute (RKI). The German Environmental Surveys are nationwide population studies conducted to determine the exposure to environmental pollutants, to explore exposure pathways and to identify sub-groups with higher exposure. GerES IV was conducted on randomly selected 1790 children aged 3-14 years from the cross-sectional sample of KiGGS. The participants of GerES IV lived in 150 sampling locations all over Germany. Field work was carried out from May 2003 to May 2006. The response rate in GerES IV was 77.3%. Due to the fact that participation in GerES IV was limited to children that had previously participated in the KiGGS study, the total response rate in GerES IV resulted in 52.6%. Response rates did neither differ significantly between West and East Germany, nor between different community sizes, age groups and gender. The basic study programme included blood samples, morning urine, tap water and house dust as well as comprehensive questionnaire-based interviews. In addition, subgroups were studied with regard to "noise, hearing capacity and stress hormones", "chemical contamination of indoor air" and "biogenic indoor contamination". A key element of the field work in GerES IV was a home visit to carry out interviews, conduct measurements and collect samples. An exception was blood sampling which was carried out within KiGGS. The quality of field work, data collection, evaluation, and chemical, biological and physical analyses was successfully evaluated by internal and external quality assurance. This comprehensive overview aims at giving other research groups the opportunity to compare different study designs or to adapt their own design to get comparable results.

Serum Thyroid-Stimulating Hormone Levels Are Associated with Blood Pressure in Children and Adolescents

It is currently unclear whether subclinical thyroid dysfunction is associated with blood pressure. Furthermore, data on the potential relation of thyroid function with blood pressure in children and adolescents are sparse. We investigated the association between serum TSH levels and blood pressure in a population-based study conducted in children aged 3-10 yr and adolescents aged 11-17 yr. Data from 6435 children and 5918 adolescents of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) were analyzed. Two readings of systolic and diastolic blood pressure were taken in a sitting position after 5 min of rest. Hypertension was defined by an increased systolic or an increased diastolic blood pressure using age-, sex-, and height-specific reference values from the KiGGS study. Serum TSH levels were measured with the electrochemiluminescence method. High and low serum TSH levels were defined according to age-specific reference limits for the assay. Continuous and categorized serum TSH levels were associated with hypertension by multivariable logistic regression. Serum TSH levels were significantly associated with hypertension in children (odds ratio=1.12; 95% confidence interval=1.00-1.25; P=0.045) and adolescents (odds ratio=1.19; 95% confidence interval=1.12-1.26; P<0.001). High serum TSH levels were positively associated with systolic and diastolic blood pressure, but not with hypertension in children and adolescents. There is a positive relationship between serum TSH levels and hypertension in children and adolescents, suggesting that subclinical hypothyroidism is associated with an increased risk of hypertension.

Juvenile obesity and its association with utilisation and costs of pharmaceuticals - results from the KiGGS study

BackgroundAccording to a national reference, 15% of German children and adolescents are overweight (including obese) and 6.3% are obese. An earlier study analysed the impact of childhood overweight and obesity on different components of direct medical costs (physician, hospital and therapists). To complement the existing literature for Germany, this study aims to explore the association of body mass index (BMI) with utilisation of pharmaceuticals and related costs in German children and adolescents.MethodsBased on data from 14, 836 respondents aged 3-17 years in the German Interview and Examination Survey for Children and Adolescents (KiGGS), drug intake and associated costs were estimated using a bottom-up approach. To investigate the association of BMI with utilisation and costs, univariate analyses and multivariate generalised mixed models were conducted.ResultsThere was no significant difference between BMI groups regarding the probability of drug utilisation. However, the number of pharmaceuticals used was significantly higher (14%) for obese children than for normal weight children. Furthermore, there was a trend for more physician-prescribed medication in obese children and adolescents. Among children with pharmaceutical intake, estimated costs were 24% higher for obese children compared with the normal weight group.ConclusionsThis is the first study to estimate excess drug costs for obesity based on a representative cross-sectional sample of the child and adolescent population in Germany. The results suggest that obese children should be classified as a priority group for prevention. This study complements the existing literature and provides important information concerning the relevance of childhood obesity as a health problem.