Establishing International Blood Pressure References Among Nonoverweight Children and Adolescents Aged 6 to 17 Years.

BACKGROUND: Several distributions of country-specific blood pressure (BP) percentiles by sex, age, and height for children and adolescents have been established worldwide. However, there are no globally unified BP references for defining elevated BP in children and adolescents, which limits international comparisons of the prevalence of pediatric elevated BP. We aimed to establish international BP references for children and adolescents by using 7 nationally representative data sets (China, India, Iran, Korea, Poland, Tunisia, and the United States). METHODS AND RESULTS: Data on BP for 52 636 nonoverweight children and adolescents aged 6 to 19 years were obtained from 7 large nationally representative cross-sectional surveys in China, India, Iran, Korea, Poland, Tunisia, and the United States. BP values were obtained with certified mercury sphygmomanometers in all 7 countries by using standard procedures for BP measurement. Smoothed BP percentiles (50th, 90th, 95th, and 99th) by age and height were estimated by using the Generalized Additive Model for Location Scale and Shape model. BP values were similar between males and females until the age of 13 years and were higher in males than females thereafter. In comparison with the BP levels of the 90th and 95th percentiles of the US Fourth Report at median height, systolic BP of the corresponding percentiles of these international references was lower, whereas diastolic BP was similar. CONCLUSIONS: These international BP references will be a useful tool for international comparison of the prevalence of elevated BP in children and adolescents and may help to identify hypertensive youths in diverse populations.

Prevalence of incorrect body posture in children and adolescents with overweight and obesity.

The ever increasing epidemics of overweight and obesity in school children may be one of the reasons of the growing numbers of children with incorrect body posture. The purpose of the study was the assessment of the prevalence of incorrect body posture in children and adolescents with overweight and obesity in Poznan, Poland. The population subject to study consisted of 2732 boys and girls aged 3-18 with obesity, overweight, and standard body mass. The assessment of body mass was performed based on BMI, adopting Cole's cutoff values. The evaluation of body posture was performed according to the postural error chart based on criteria complied by professor Dega. The prevalence rates of postural errors were significantly higher among children and adolescents with overweight and obesity than among the group with standard body mass. In the overweight group, it amounted to 69.2% and in the obese group to 78.6%. CONCLUSION:  The most common postural deviations in obese children and adolescents were valgus knees and flat feet. Overweight and obesity in children and adolescents, predisposing to higher incidence of some types of postural errors, call for prevention programs addressing both health problems. What is Known: • The increase in the prevalence of overweight and obesity among children and adolescents has drawn attention to additional health complications which may occur in this population such as occurrence of incorrect body posture. What is New: • The modified chart of postural errors proved to be an effective tool in the assessment of incorrect body posture. • This chart may be used in the assessment of posture during screening tests and prevention actions at school.

Who is at higher risk of hypertension? Socioeconomic status differences in blood pressure among Polish adolescents: a population-based ADOPOLNOR study.

UNLABELLED: In Poland, there is no data on parental socioeconomic status (SES) as a potent risk factor in adolescent elevated blood pressure, although social differences in somatic growth and maturation of children and adolescents have been recorded since the 1980s. This study aimed to evaluate the association between parental SES and blood pressure levels of their adolescent offspring. A cross-sectional survey was carried out between 2009 and 2010 on a sample of 4941 students (2451 boys and 2490 girls) aged 10-18, participants in the ADOPOLNOR study. The depended outcome variable was the level of blood pressure (optimal, pre- and hypertension) and explanatory variables included place of residence and indicators of parental SES: family size, parental educational attainments and occupation status, income adequacy and family wealth. The final selected model of the multiple multinomial logistic regression analysis (MLRA) with backward elimination procedure revealed the multifactorial dependency of blood pressure levels on maternal educational attainment, paternal occupation and income adequacy interrelated to urbanization category of the place of residence after controlling for family history of hypertension, an adolescent's sex, age and weight status. Consistent rural-to-urban and socioeconomic gradients were found in prevalence of elevated blood pressure, which increased with continuous lines from large cities through small- to medium-sized cities to villages and from high-SES to low-SES familial environments. The adjusted likelihood of developing systolic and diastolic hypertension decreased with each step increase in maternal educational attainment and increased urbanization category. The likelihood of developing prehypertension decreased with increased urbanization category, maternal education, paternal employment status and income adequacy. Weight status appeared to be the strongest confounder of adolescent blood pressure level and, at the same time, a mediator between their blood pressure and parental SES. CONCLUSION: The findings of the present study confirmed socioeconomic disparities in blood pressure levels among adolescents. This calls for regularly performed blood pressure assessment and monitoring in the adolescent population. It is recommended to focus on obesity prevention and socioeconomic health inequalities by further trying to improve living and working conditions in adverse rural environments.

[Association between dental caries and nutritional status of 7-and 12-years-old children]. / Zaleznosc wystepowania próchnicy od stanu odzywienia u dzieci 7-i 12-letnich.

UNLABELLED: One of the etiological factors of dental caries are improper eating habits, which also influence the nutritional state of the organism. This similarity tends to establish the relationship between the intensity of tooth decay, and body weight disorders. AIM: The aim of this study was to assess the prevalence of dental caries in 7 and 12-year-old children, depending on the nutritional status. MATERIAL AND METHODS: The study included 225 children of both sex, age 7 (132) and 12 years (93) attending to randomly selected schools in Poznan. Dental examination was performed by dentists in schools in artificial light using mirrors and dental probe (criteria according to WHO 1997 ). Based on collected data, caries frequency and caries intensity were calculated (DMF-t -7 and 12-year-olds and dmf-t 7-year olds). Anthropometric measurements such as height and weight were made by school nurses in accordance with guidelines for the performance of screening tests for people of school age. A deficiency or excess body weight in surveyed children rated BMI (Body Mass Index), including percentile ranges for the population of children in Poznan. Assessment of dental caries in groups of pupils were formed due to nutritional status of the respondents i. e. normal-weight and underweight and overweight. RESULTS: Caries frequency in children of normal weight in the population of 7-year-olds was 82.2% and 53.2% of children aged 12 years. In the group of 7-year-old pupils with overweight and underweight was respectively, 95.0% and 90.9%, 84.2% and 50.0% in the older group. A statistically significant difference between the attendance of dental caries in a group of 12-year-old children with overweight and normal weight and its deficiency was show. The average value of dmf-t in 7-year-old children was 4.02, and the DMF-permanent dentition - 0.19 and the children with over- and underweight respectively dmf- 4.25 and 3,82 and DMF- 0.35 and 0,27. In population of 12-year olds caries DMF was - 1.62, and for children with overweight and underweight, respectively, 2.68 and 1.25. Approximately 66.7% of 12- year old children were classified as normal weight, 20.4% as overweight and 12,9% as underweight, in the 7- year olds respectively 76.5%, 15.2% and 8.3%. Statistically relevant difference between DMF-t values at examined children of both gender with normal weight and overweight were observed only in the group of 12 years old. The surveys revealed that with increase of body the weight prevalence of dental caries grows in the group of older children. CONCLUSION: The children with observed abnormal body weight status should be classified in the higher dental caries risk group.

Body mass index percentiles and elevated blood pressure among children and adolescents.

It is well established that obesity is associated with an increased risk of elevated and high blood pressure (BP) in children and adolescents. However, it is uncertain whether there is an increase in the risk of elevated and high BP associated with an increase of body mass index (BMI) among children and adolescents whose BMI is in the accepted normal range. Data were available for 58 899 children and adolescents aged 6-17 years from seven national cross-sectional surveys in China, India, Iran, Korea, Poland, Tunisia, and the United States. The subjects were divided into eight percentile subgroups according to their BMI levels based on the World Health Organization recommendations. Elevated BP and high BP were defined using the 2016 international child BP criteria. Compared with the reference subgroup of the 5th-24th percentiles, the odds ratios (ORs) for high BP were 1.27 (95% confidence interval [CI], 1.14-1.41; P < 0.001) in the 25th-49th percentile subgroup, 1.55 (95% CI, 1.39-1.73; P < 0.001) in the 50th-74th percentile subgroup, and 2.17 (95% CI, 1.92-2.46; P < 0.001) in the 75th-84th percentile subgroup, respectively, after adjustment for sex, age, race/ethnicity, height and country. Additionally, the corresponding ORs for elevated BP were 1.21 (95% CI, 1.10-1.32; P < 0.001), 1.55 (95% CI, 1.42-1.69; P < 0.001), and 1.80 (95% CI, 1.62-2.01; P < 0.001), respectively. In conclusion, a BMI in the 25th-84th percentiles, within the accepted normal weight range, was associated with an increased risk of elevated and high BP among children and adolescents. It is important for children and adolescents to keep a BMI at a low level in order to prevent and control hypertension.

International Waist Circumference Percentile Cutoffs for Central Obesity in Children and Adolescents Aged 6 to 18 Years.

CONTEXT: No universal waist circumference (WC) percentile cutoffs used have been proposed for screening central obesity in children and adolescents. OBJECTIVE: To develop international WC percentile cutoffs for children and adolescents with normal weight based on data from 8 countries in different global regions and to examine the relation with cardiovascular risk. DESIGN AND SETTING: We used pooled data on WC in 113,453 children and adolescents (males 50.2%) aged 4 to 20 years from 8 countries in different regions (Bulgaria, China, Iran, Korea, Malaysia, Poland, Seychelles, and Switzerland). We calculated WC percentile cutoffs in samples including or excluding children with obesity, overweight, or underweight. WC percentiles were generated using the general additive model for location, scale, and shape (GAMLSS). We also estimated the predictive power of the WC 90th percentile cutoffs to predict cardiovascular risk using receiver operator characteristics curve analysis based on data from 3 countries that had available data (China, Iran, and Korea). We also examined which WC percentiles linked with WC cutoffs for central obesity in adults (at age of 18 years). MAIN OUTCOME MEASURE: WC measured based on recommendation by the World Health Organization. RESULTS: We validated the performance of the age- and sex-specific 90th percentile WC cutoffs calculated in children and adolescents (6-18 years of age) with normal weight (excluding youth with obesity, overweight, or underweight) by linking the percentile with cardiovascular risk (area under the curve [AUC]: 0.69 for boys; 0.63 for girls). In addition, WC percentile among normal weight children linked relatively well with established WC cutoffs for central obesity in adults (eg, AUC in US adolescents: 0.71 for boys; 0.68 for girls). CONCLUSION: The international WC cutoffs developed in this study could be useful to screen central obesity in children and adolescents aged 6 to 18 years and allow direct comparison of WC distributions between populations and over time.

Blood pressure references for Polish children and adolescents.

The objective of this study was to develop age- and gender-specific reference ranges for blood pressure in a large national database on blood pressure levels throughout childhood and adolescence in young Poles. A prospective cross-sectional study was performed in 2002-2005 in the representative sampling sites, selected randomly from the entire Poland. Altogether, 6,447 school pupils, aged 7-18 years, were involved in the study of which 3,176 were boys and 3,271 were girls. Statistical analysis was performed using STATISTICA for Windows 7.1. The normal range of blood pressure, determined by age and the category of body height percentiles, revealed percentiles values which might serve as reference values to identify cases of high normal blood pressure (the mean blood pressure between 90th and 95th percentiles for age and gender) and hypertension (the mean blood pressure equals or exceeds the 95th percentiles on at least three occasions).

Impact of the 2017 American Academy of Pediatrics Guideline on Hypertension Prevalence Compared With the Fourth Report in an International Cohort.

In 2017, the American Academy of Pediatrics (AAP) updated the clinical practice guideline for high blood pressure (BP) in the pediatric population. In this study, we compared the difference in prevalence of elevated and hypertensive BP values defined by the 2017 AAP guideline and the 2004 Fourth Report and estimated the cardiovascular risk associated with the reclassification of BP status defined by the AAP guideline. A total of 47 200 children and adolescents aged 6 to 17 years from 6 countries (China, India, Iran, Korea, Poland, and Tunisia) were included in this study. Elevated BP and hypertension were defined according to 2 guidelines. In addition, 1606 children from China, Iran, and Korea who were reclassified upward by the AAP guideline compared with the Fourth Report and for whom laboratory data were available were 1:1 matched with children from the same countries who were normotensive by both guidelines. Compared with the Fourth Report, the prevalence of elevated BP defined by the AAP guideline was lower (14.9% versus 8.6%), whereas the prevalence of stages 1 and 2 hypertension was higher (stage 1, 6.6% versus 14.5%; stage 2, 0.4% versus 1.7%). Additionally, comparison of laboratory data in the case-control study showed that children who were reclassified upward were more likely to have adverse lipid profiles and high fasting blood glucose compared with normotensive children. In conclusion, the prevalence of elevated BP and hypertension varied significantly between both guidelines. Applying the new AAP guideline could identify more children with hypertension who are at increased cardiovascular risk.

Height-specific blood pressure cutoffs for screening elevated and high blood pressure in children and adolescents: an International Study.

Pediatric blood pressure (BP) reference tables are generally based on sex, age, and height and tend to be cumbersome to use in routine clinical practice. In this study, we aimed to develop a new, height-specific simple BP table according to the international child BP reference table based on sex, age and height and to evaluate its performance using international data. We validated the simple table in a derivation cohort that included 58,899 children and adolescents aged 6-17 years from surveys in 7 countries (China, India, Iran, Korea, Poland, Tunisia, and the United States) and in a validation cohort that included 70,072 participants from three other surveys (China, Poland and Seychelles). The BP cutoff values for the simple table were calculated for eight height categories for both the 90th ("elevated BP") and 95th ("high BP") percentiles of BP. The simple table had a high performance to predict high BP compared to the reference table, with high values (boys/girls) of area under the curve (0.94/0.91), sensitivity (88.5%/82.9%), specificity (99.3%/99.7%), positive predictive values (93.9%/97.3%), and negative predictive values (98.5%/97.8%) in the pooled data from 10 studies. The simple table performed similarly well for predicting elevated BP. A simple table based on height only predicts elevated BP and high BP in children and adolescents nearly as well as the international table based on sex, age, and height. This has important implications for simplifying the detection of pediatric high BP in clinical practice.

Environmental variation in the prevalence of hypertension in children and adolescents - is blood pressure higher in children and adolescents living in rural areas?

INTRODUCTION: Despite considerable progress in diagnostic methods and treatment options, cardiovascular diseases constitute a serious health issue in Poland, and hypertension is considered one of the main risk factors in the incidence of the diseases. OBJECTIVES: The aim of this study is to assess the values of arterial blood pressure among adolescents in the context of urban and rural environments. MATERIALS AND METHOD: The study was carried out on a representative, randomly selected group of youths aged 10-18 years, participating in the ADOPOLNOR project. Prior to blood pressure measurement, each pupil was assessed according to anthropomorphic principles. The BP measurements strictly followed the guidelines of the Fourth Protocol of the American Working Group of High Blood pressure in Children and Adolescents. RESULTS: Mean values of systolic blood pressure (SBP) in boys in rural areas were higher in every age group than in the boys in urban areas. Higher values of systolic and diastolic blood pressure were observed also in girls in rural areas. BP values sufficiently high for the diagnosis of hypertension were observed in 12.8% of the rural boy population but only in 6.7% of the boys from the urban environment. The difference is statistically significant. The girls in rural areas (13.3%) had twice the incidence of elevated BP values in comparison with the girls in urban areas (7.2%) and, as in boys, the difference is statistically significant. CONCLUSIONS: The high proportion of pupils with elevated arterial blood pressure observed in the rural areas of Wielkopolska calls for regularly performed BP assessment and monitoring in this populatio.

Trends in the Incidence Rates of Chronic Hepatitis B in Poland in the Years 2005 - 2013.

BACKGROUND: The prevalence of newly-diagnosed cases of chronic hepatitis is decisive for the overall incidence rate of hepatitis B observed in Poland. OBJECTIVES: We aimed to determine the chronic hepatitis B incidence trends in Poland, taking into consideration the ages, genders, and environments of the patients. METHODS: The study is based on aggregated data from Polish descriptive epidemiological studies for the period of 2005 to 2013 (i.e., hepatitis B incidence numbers and ratios, including mixed HBV and HCV infections) as published in the annual bulletins Choroby zakazne i zatrucia w Polsce (Infectious diseases and poisonings in Poland] drawn up by the laboratory for the monitoring and analysis of epidemiological status of the department of epidemiology at the national institute of public health - national institute of hygiene (NIPH-NIH). Poland, a central European country situated in the humid continental climate zone, is classified as a highly developed country. In the analyzed period, the Polish population consisted of about 38 million people, more than 19 million of whom were women, and more than 18 million of whom were men. Among European countries, Poland has the smallest number of national and ethnic minorities. For the purposes of epidemiological supervision, a special definition of acute hepatitis B was adopted in Poland in 2005, which facilitated separate registration of acute and chronic cases. RESULTS: A significantly increasing chronic hepatitis B incidence trend was observed in the population of Poland, with considerable increases in incidence rates for both men and women alike. The incidence rates for inhabitants of both urban and rural areas also showed an increasing tendency. Chronic hepatitis B occurred more frequently in men and in urban areas. For each of the five-year age groups encompassing patients between 20 and 54 years of age, the increase in the incidence rate proved to be significant. CONCLUSIONS: The registered increase in the incidence rate of chronic hepatitis B in Poland is a consequence of the new registration of cases of chronic hepatitis B acquired in the past. The problem of chronic hepatitis B can be solved by improving epidemiological supervision, enhancing the detection of frequently asymptomatic infections, and by providing easier access to optimized therapies.

Performance of Eleven Simplified Methods for the Identification of Elevated Blood Pressure in Children and Adolescents.

The identification of elevated blood pressure (BP) in children and adolescents relies on complex percentile tables. The present study compares the performance of 11 simplified methods for assessing elevated or high BP in children and adolescents using individual-level data from 7 countries. Data on BP were available for a total of 58 899 children and adolescents aged 6 to 17 years from 7 national surveys in China, India, Iran, Korea, Poland, Tunisia, and the United States. Performance of the simplified methods for screening elevated or high BP was assessed with receiver operating characteristic curve (area under the curve), sensitivity, specificity, positive predictive value, and negative predictive value. When pooling individual data from the 7 countries, all 11 simplified methods performed well in screening high BP, with high area under the curve values (0.84-0.98), high sensitivity (0.69-1.00), high specificity (0.87-1.00), and high negative predictive values (≥0.98). However, positive predictive value was low for most simplified methods, but reached ≈0.90 for each of the 3 methods, including sex- and age-specific BP references (at the 95th percentile of height), the formula for BP references (at the 95th percentile of height), and the simplified method relying on a child's absolute height. These findings were found independently of sex, age, and geographical location. Similar results were found for simplified methods for screening elevated BP. In conclusion, all 11 simplified methods performed well for identifying high or elevated BP in children and adolescents, but 3 methods performed best and may be most useful for screening purposes.

[Variability of blood pressure in children and youth in the city of Poznan]. / Ocena kierunku zmian cisnienia tetniczego u dzieci i mlodziezy miasta Poznania.

The aim of the present work has been to analyse the differentiation of blood pressure in the population of children and youth in the city of Poznan, based on the cross-sectional studies performed in 1986, 1991 and 1996, and to determine the tendency of changes. The population subject to investigation comprised a representative group of children and adolescents from Poznan, aged 10 to 18. In the Cross-Sectional Pressure Study conducted in 1986, 5889 subjects were tested. In 1991, 515 and in 1996, 1889 subjects were examined. The pressure measurement, as well as the subjective and objective examination were performed according to the guidelines of the report of the Task Force on Blood Pressure Control in Children, as well as the guidelines related to the principles of screening studies. The mean values of the systolic and diastolic blood pressure in boys and girls in the 1996 were lower in comparison with population examined in 1986. The studies were performed according to the same methodology and code of conduct. The systolic blood pressure in boys aged 18 in 1996 was higher than in 1986. We observed a favourable tendency of the decrease in percentage of subjects with blood pressure exceeding the 95th percentile in 1996.

[Juvenile cigarette smoking]. / Palenie tytoniu wsród dzieci i mlodziezy.

Cigarette smoking continues to be the main undesirable habit among children and adolescents. Its monitoring may provide valuable information about the effectiveness of health education programmes. The aim of the study was to assess the prevalence of cigarette smoking among the schoolchildren in the city of Poznan. The study was conducted in the school years 2000/2001 and 2001/2002 on the group of 1909 pupils. A lecture "Why I do not smoke" was delivered in every class prior to the distribution of questionnaire about cigarette smoking. 20% of children-more boys than girls-admitted they smoke. Percentage of smokers increases with age. A significant increase in the habit was observed among the 14-16 year olds. There continuous is still a need for health education among the young people in order to limit the unhealthy habits.

[Death due to congenital malformations in infants born in Poznan in 1998-2001]. / Zgony z powodu wad wrodzonych niemowlat urodzonych w Poznaniu w latach 1998-2001.

Congenital malformations have always been one of major medical and social problems. In epidemiological studies they emerge as one of the main causes of infant mortality. The aim of the study was to analyze the mortality of infants born and deceased in Poznan in years 1998-2001. The main source of information were death certificates which contained the following information: immediate and underlying cause of death, date of birth and date of death, address, birth weight, gestational week. In the analyzed period 50 infants died from congenital malformations. Circulatory system defects, CNS defects and multiple malformations were the most frequent causes of death. The low birth weight children prevailed among those who died from congenital malformations.

[Hip fracture as an important mortality risk in elderly people]. / Upadki ze zlamaniem szyjki kosci udowej jako wazna przyczyna zgonów.

In recent years much attention has been paid to trauma from accident falls among elderly. It is estimated that almost 1/3 of the population of 65 and over experience one fall a year. The falls are responsible for almost 90% of all fractures in this population and are the most common cause of death in the accidents, injuries and poisonings category. In the study mortality from hip fractures in Poznan, in years 1990-2000 was analyzed. For that purpose death certificates of the residents of Poznan were analyzed, in which hip fracture was the underlying cause of death. It was the continuation of the research conducted in the 80 degrees. In the studied period hip fractures contributed to a lesser and lesser degree in the mortality from external causes. In the beginning of the 90 degrees the percentage was 25, while in the year 2000--only 12.6. Mortality from the hip fractures was observed mainly in people older than 55, predominantly women (68% of deaths in 1990 and 87% in 1996). At the same time the overall mortality rate for both sexes would decrease systematically.

[Mortality trends from malignant diseases in the population of Poznan in the years 1991-2000]. / Nadumieralnosc na skutek chorób nowotworowych w populacji miasta Poznania w latach 1991-2000.

Since the 70's Polish epidemiological studies from give evidence to male mortality, predominantly in the working age. The results of the analysis of overall mortality in the population of Poznan in the years 1990-1999 were in the line of overall results from Poland. Throughout the period under study we noted male overmortality in Poznan, which would start in the age group 15-19 (with the exception of 1996) and would continue up to the age 85-89. The aim of the study was to assess the phenomenon of overmortality from neoplasms in the population of Poznan. In the study secondary sources of information were used such as death certificates of permanent residents of Poznan in the years 1991-2000. Male overmortality was given as a percentage and was calculated as a ratio of female mortality rate to male mortality rate. The increase in the number of deaths from malignancies in Poznan in the 90's applied to both sexes but overall male mortality for this cause was higher than for females. The analysis of the mortality for particular group of tumors as well as selected tumors showed that overmortality is not specific to male population. The increase in female deaths from bowel cancer was reflected in the female overmortality in four out of ten years study. Periodic overmortality in the population was also detected for other neoplasms of the alimentary tract e.g. liver and rectum.

[Monitoring the progress of physical development of children and youth in the city of Poznan]. / Monitorowanie procesu rozwoju dzieci i mlodziezy miasta Poznania.

The aim of the present work was to assess the short-time changes of body height and weight and the health status of 286 children, aged 10. The measurement of body height and weight was performed within the last three years. The children were examined by a team of paediatricians. Defects of vision, posture defects, abnormalities of circulatory system, and obesity--were the most common findings in physical examination. 4% pupils had the weight deficiency, 12% boys and 7% girls were overweight. The height deficiency was observed among 5% boys and 6% girls. The presented findings indicate an important role of monitoring of children' health status by a school nurse and also by a school-physician.

[Blood pressure of children and adolescents in the Mazowiecki and Wielkopolski provinces]. / Cisnienie tetnicze dzieci i mlodziezy województwa mazowieckiego i wielkopolskiego.

The aim of the study is evaluation of occurrence of elevated blood pressure values in Wielkopolskie and Mazowieckie provinces. The population studied was a representative sample of children & adolescents age 7-18 (1905 in Mazowieckie and 1805 from Wielkopolskie province). The methodology of BP measurement and classification of hypertension followed the guidelines of the III Report of the Task Force on Blood Pressure Control in Children. The occurrence of elevated BP values were significantly higher in Mazowieckie region.

Waist Circumference and Waist-to-Height Ratio Distributions in Polish and German Schoolchildren: Comparative Analysis.

BACKGROUND: To analyze differences in the distributions of waist circumference (WC) and waist-to-height ratio (WHtR) between Polish (PL) and German (GE) children and adolescents. METHODS: Two samples of children and adolescents aged 7-18 y: From PL (n = 11,326) GE (n = 8,218) participated. The two WC cut-off points (WC1 as central fat distribution and WC2 as central obesity) corresponding at age 18 to the adult criteria were determined. Furthermore, the mean WC cut-off points (WC1m, WC2m) for boys and girls aged 14-18 from both countries were evaluated. For the WHtR, values over 0.5 were used as a definition of central fat distribution. The effect of different WC and WHtR criteria on the prevalence of abdominal obesity in both study groups was evaluated. RESULTS: The mean and percentile values of WC and WHtR were generally higher in all German children as compared to their peers from Poland. When WC1m is used, the mean (95% CI) prevalence of central fat distribution in the 14-18 y Polish groups was lower (P < 0.05) than those from Germany (boys: 4.4% (3.6-5.2) vs. 8.9% (7.3-10.5); girls: 10.7% (9.0-12.3) vs. 26.4% (23.2-29.6)), whereas, using the WHtR > 0.5, the results were similar for boys - 6.7% (5.9-7.5) vs. 8.5% (8.1-8.9); they were significantly (P < 0.05) lower for Polish and German girls: 5.3% (5.0-5.6) vs. 12.7% (9.7-16.4). The prevalence of central obesity using WC2m as a criterion in the Polish vs. German groups was as follows: (boys - 1.1% (0.8-1.4) vs. 3.1% (2.2-4.0), P < 0.05; girls - 3.1% (2.5-3.7) vs. 10.2% (8.4-12.0), P < 0.05). CONCLUSIONS: The results highlight the greater central obesity associated with the German children, both in terms of WC and WHtR, in comparison to their peers from Poland. The prevalence of AO is significantly associated with the criteria used. The results demonstrate the need for the development of international WC references for pediatric subjects.