Abdominal obesity, metabolic syndrome in type 1 diabetic children and adolescents

ORIGINAL ARTICLES / Prace oryginalne Pediatric Endocrinology, Diabetes and Metabolism 2009, 15, 4, 233-239 ISSN 1234-625X Abdominal obesity, metabolic syndrome in type 1 diabetic children and adolescents Agnieszka Szadkowska, Iwona Pietrzak, Joanna Szlawska, Anna Kozera, Anna Gadzicka, Wojciech Młynarski Department of Pediatrics, Oncology, Hematology and Diabetology, Medical University of Lodz, Poland Klinika Pediatrii, Onkologii, Hematologii i Diabetologii Uniwersytetu Medycznego w Łodzi Address for correspondence: Agnieszka Szadkowska MD, PdD Klinika Pediatrii, Onkologii, Hematologii, Diabetologii, Uniwersytet Medyczny w Łodzi ul. Sporna 36/50; 91-738 Łódź; Poland; tel.: (+48 42) 617 77 91; fax: (+48 42) 617 77 98; e-mail: agnieszka.szadkowska@wp.pl Abstract Introduction: The rapid rising prevalence of childhood obesity is related to the increased risk of cardiovascular morbidities. The type 1 diabetic patients are the group at special risk of macroangiopathy. The aim of the study was to estimate the prevalence of abdominal obesity in type 1 diabetic children compared to the general population, and to estimate the prevalence of metabolic syndrome diagnosed according to IDF criteria in type 1 diabetic children and adolescents. Material and methods: 163 patients with type 1 diabetes mellitus (91 male) aged from 10 to 18 years were included into the study. The diabetes duration ranged from 0.5 to 15.2 years. The height, weight, waist circumference, body fat and blood pressure were measured. HbA 1 c and plasma lipids concentrations were examined. Body mass index, waist/height ratio (WHtR) and daily dose of insulin were calculated. Estimated glucose disposal rate (egdr) as indicator of insulin resistance was calculated according to own formula. Results: Abdominal obesity diagnosed as WHtR >0.5 was found in 19 patients (11.7%, CI95% 6.7-16.6). Associations between WHtR and HbA 1 c (r=0.18; p=0.027), cholesterol-hdl (r=-0.22; p=0.004), systolic (β=0.37; p <0.001) and diastolic blood pressure (β=0.19, p=0.046) and Body Fat% (r=0.59; p <0.001) were observed. The prevalence of abdominal obesity in diabetic children was higher than in the general population (12.2 vs. 6.8%; p=0.030). The metabolic syndrome was found in 12 individuals (7.4%, CI95% 3.4-11.4). Patients with metabolic syndrome were older (16.6 vs. 14.7 years; p=0.006) and their Body Fat% was higher (21 vs. 30%; p <0.001) compared to patients not fulfilling the metabolic syndrome criteria. Conclusions: The prevalence of abdominal obesity in diabetic children is higher than in the general population. WHtR is associated with components of metabolic syndrome. Patients with metabolic syndrome are older and they are characterized by increased body fat. KEY WORDS: abdominal obesity, metabolic syndrome, children and adolescents, type 1 diabetes mellitus Streszczenie Wprowadzenie: Obecnie na świecie obserwuje się coraz częstsze występowanie otyłości, która zwiększa ryzyko rozwoju chorób układu krążenia. Pacjenci chorzy na cukrzycę typu 1 stanowią grupę szczególnie narażoną na występowanie makroangiopatii. Celem pracy była ocena częstości występowania otyłości brzusznej u dzieci chorych na cukrzycę typu 1 i porównanie jej z występowaniem otyłości brzusznej w populacji ogólnej, a także ocena częstości występowania zespołu metabolicznego według kryteriów IDF i jego związku z czasem trwania choroby oraz wyrównaniem metabolicznym cukrzycy. Materiał i metody: Badaniami objęto 163 dzieci chorych na cukrzycę typu 1 w wieku 10-18 lat, z czasem trwania choroby 0,5-15,2 roku. U badanych dokonano pomiaru wzrostu, masy ciała, obwodu talii, ciśnienia tętniczego, ilości tkanki tłuszczowej w organizmie (Body Fat%). Oznaczono stężenie cholesterolu całkowitego, cholesterolu-hdl, triglicerydów, HbA 1 c. Obliczono wskaźnik BMI (body mass index), talia/wzrost (WHtR) i dobowe zapotrzebowanie na insulinę. Metodą pośrednią obliczono egdr (estimated Glucose Disposal Rate) wykładnik insulinooporności. Wyniki: Otyłość brzuszną zdiagnozowaną na podstawie kryterium WHtR >0,5 rozpoznano u 19 pacjentów z cukrzycą typu 1 (11,7%, CI95% 6,7-16,6). Odnotowano związek między WHtR a HbA 1 c (r=0,18; p=0,027), stężeniem cholesterolu-hdl (r=-0,22; p=0,004), wartościami skurczowego (β=0,37; p <0,001) i rozkurczowego ciśnienia tętniczego (β=0,19; p=0,046) oraz Body Fat% (r=0,59; p <0,001). U dzieci chorych na cukrzycę istotnie częściej rozpoznano otyłość brzuszną w stosunku do jej występowania w ogólnej populacji (12,2 vs. 6,8%, p=0,030). U 12 osób (7,4%, CI95% 3,4-11,4) rozpoznano zespół metaboliczny. Pacjentów z zespołem metabolicznym cechował starszy wiek (16,6 vs.14,7 lat, p=0,006) i większa Fat% (21 vs. 30%; p <0,001) w porównaniu do dzieci bez zespołu. Wnioski: U dzieci i młodzieży chorej na cukrzycę typu 1 otyłość brzuszna występuje częściej niż w populacji ogólnej. Wskaźnik WHtR wykazuje związek z komponentami zespołu metabolicznego. Chorzy z zespołem metabolicznym charakteryzują się starszym wiekiem i zwiększoną zawartością tłuszczu w organizmie. SŁOWA KLUCZOWE: otyłość brzuszna, zespół metaboliczny, dzieci i młodzież, cukrzyca typu 1 Introduction The recent epidemiologic data show a rising prevalence of overweight and obesity in adults (1). This problem is also observed in the population of children and adolescents (2, 3). Excessive total body mass along with an increased amount of fat mass are characteristic for overweight and obesity. Nowadays it is known that body fat is not only an energy stock but 233

Szadkowska A., Pietrzak I., Szlawska J. et al. Abdominal obesity, metabolic syndrome in type 1 diabetic children and adolescents Pediatric Endocrinology, Diabetes and Metabolism 2009, 15, 4 234 also a very active secreting organ. Fat tissue produces adipokines most of which take part in the regulation of insulin sensitivity (4). Insulin resistance together with hyperglycemia, dyslipidemia and hypertension induces arteriosclerosis leading to develop cardiovascular disease. Coexistence of insulin resistance and disorders mentioned above was a reason for combining them into a common syndrome, called metabolic syndrome. Nowadays there are multiple definitions of metabolic syndrome in adults (5, 6). There are many problems in defining the metabolic syndrome in children and adolescents (7, 8). These difficulties result from physiologic changes of clinical features with age and development. Moreover there is lack of prospective data that let to define a border value of metabolic parameters showing increased risk of cardiovascular disease in adult life. In 2007 International Diabetes Federation established criteria of metabolic syndrome in children (tab. I) (9). In this definition an emphasis was put on a waist circumference. This parameter in many studies was identified as an independent predictor of insulin resistance. This is the reason why in IDF definition it is an obligatory parameter of metabolic syndrome. There is an increased risk of macrovascular complications in patients with type 1 diabetes mellitus. The development of these complications is connected with insulin resistance coexistence (10-12). This is the reason why in type 1 diabetic children special attention should be also focused on prevalence of abdominal obesity, the predictor of insulin resistance. The aims of the study 1. Estimation of abdominal obesity prevalence in type 1 diabetic children and comparison with the prevalence of abdominal obesity in the general population of Lodz children. 2. Estimation of metabolic syndrome prevalence and its relation to diabetes duration and metabolic control. Material and methods Study group Type 1 diabetic children and adolescents of Diabetology Outpatient Clinic of University Clinical Hospital No. 4 of Medical University of Lodz were examined. The inclusion criteria were: age 10-18 years, diabetes duration >0.5 year, no occurrence of ketoacidosis during 6 last months before the study, living in the Lodz district. All the following patients who came for the follow-up examination to the diabetology department between November 2007 and March 2009 and fulfilled inclusion criteria were included into the study. The patients suffering from infections or other diseases that can influence the results of the study were excluded. The data of 163 patients (72 girls and 91 boys) at the age of 10-18 years (mean 14.8±2.4 years) were analyzed. The diabetes duration was 0.5-15.2 years (mean 6.2±4.2 years). All children were treated by intensive insulin therapy: 96 using a multiple insulin injections regimen, 67 undergoing treatment with continuous subcutaneous insulin infusion by insulin pump. The study protocol was approved by the Ethical Committee of the Medical University of Lodz. Informed consent was obtained from parents and informed assent from the children. Height and weight measurement was performed with medical scales and anthropometer in the morning in fasting state in light clothes. Body mass was measured with the 100 g and height with 0.5 cm accuracy. Waist circumference was measured with the use of inextensible measuring tape with the accuracy of 1 mm. Fat mass content (FAT) was measured with electric bioimpedance with the use of eight electrode scales TGF-410GS Body Analyzer (Tanita, Japan). Body Mass Index (BMI) and Waist/Height Rate (WHtR) were calculated. According to some researchers abdominal obesity was defined by the value of WHtR. The border value >0.5 is constant for both sexes and all age groups. Blood pressure was measured three times after 5-minute rest in the sitting position on both upper limbs with the use of automatic manometer (Omron M4 Plus, Omron Healthcare Europe, Hoofddorp, Holland). The mean value of the second and the third measurement was calculated. The measurements taken on the limb with higher blood pressure values were analyzed. HbA 1 c was measured with high-pressure liquid chromatography method (HPLC) with the use of Variant (BioRad Laboratories, Marnes-la-Coquette, Germany). Lipids concentration (total cholesterol, HDL-cholesterol and triglycerides) in the serum was determined by enzymatic method with the use of commercial tests (Vitros Chemistry, Ortho-Clinical Diagnostics, Johnson&Johnson Company. Rochester, NY, USA). Metabolic syndrome was diagnosed according to the International Diabetes Federation consensus definition shown in the table I. All type 1 diabetic patients fulfilled hyperglycaemia criterion, so in this study insulin resistance instead of hyperglycaemia was taken into account. The estimated Glucose Disposal Rate (egdr) <5.5 mg/kg/min was defined as the presence of insulin resistance (13). The egdr was calculated according to the formula established in previous studies (egdr=20.91+1.51 (sex)-0.10 (age)-0.13 (waist)-0,30 (HbA 1 c)- 2.11 (DDI), where 20.91 is constant value, sex (female 0, male 1 ), age (years), waist waist circumference (cm), HbA 1 c glycated hemoglobin (%) (13). Abdominal obesity was evaluated according to growth charts for Lodz children. Statistical analysis All statistical analyses were conducted using the statistical package Statistica version 6.1 (StatSoft Inc., Tulsa, OK, USA). Shapiro-Wilk test was used to determine whether the distribution of preliminary quantity variables is normal. Group comparisons were performed with the use of non-parametric variance analysis. Yates corrected χ2 test or Fisher s exact test, depending on the number of compared cases, were used for frequencies comparisons. Pearson correlation coefficient was calculated to evaluate the dependence of two quality variables. In the case of adjustment towards other variables, multiple regression analysis were performed. P values <0.05 was considered as statistically significant. Results The characteristics of the study group are shown in the table II. Figure 1 depicts WHtR values for boys and girls. No significant differences in the mean values between sexes and calendar age were noticed.

Szadkowska A., Pietrzak I., Szlawska J. i wsp. Abdominal obesity diagnosed according to WHtR >0.5 criterion was found in 19 type 1 diabetic patients (11.7%, CI95% 6.7-16.6). In this study group size no significant difference in the prevalence of abdominal obesity between girls and boys was identified (9.72 vs. 13.19%; p=0.491). Positive correlation between WHtR and HbA 1 c (r=0.18; p=0.027) was observed. No relationship with diabetes duration or insulin dose was noticed. Relations between WHtR and HDL-cholesterol concentration (r=-0.22; p=0,004), values of systolic (β=0.37; p <0.001; adjusted to sex and age) and diastolic blood pressure (β=0.19; p=0.046; adjusted to sex and age) were found. Moreover, significant correlation between WHtR and body fat (r=0.59; p<0.001 was observed (fig. 2). In the table III comparison of abdominal obesity prevalence in type 1 diabetic adolescents and population of Lodz children at the age of 14-18 years is shown (14). IDF consensus definition was used to diagnose metabolic syndrome. Abdominal obesity was recognized in 32 individuals (19.6%). In 14 patients (8.59%) hypertriglyceridemia and in 4 patients (2.45%) decreased HDL-cholesterol concentration were identified. In 33 patients (20.3%) blood pressure values above 90 pc for age and sex were found. Insulin resistance was observed in 49 individuals (30.1%). According to IDF definition metabolic syndrome was diagnosed in 12 individuals (7.4%, CI95% 3.4-11.4%). No differences in prevalence of metabolic syndrome between girls and boys (11.11 vs. 6.59%, p=0.459) were found. Patients with metabolic syndrome were older than children without it and higher content of fat tissue was characteristic for them (tab. IV). Discussion Abdominal obesity is considered to be an indicator of insulin resistance, which is a risk factor of cardiovascular disease. In adults, the component of abdominal obesity, expressed as waist circumference, occurs in most metabolic syndrome definitions. However, cut off point of waist circumference that allows diagnosing abdominal obesity is changing. Table I: IDF consensus definition of metabolic syndrome in children (by 9) Tabela I: Definicja i kryteria rozpoznawania zespołu metabolicznego u dzieci wg IDF (9) Age group [years] Grupa wiekowa [lata] 6-10 years 6-10 lat 10-16 years Metabolic syndrome 10-16 lat Zespół metaboliczny >16 years metabolic syndrome >16 lat zespół metaboliczny Obesity (WC) Obwód talii 90 percentile 90 percentyla 90 percentile or adult cut-off if lower 90 percentyla lub wartości jak dla osób dorosłych, jeżeli są niższe od 90 percentyla Triglycerides Triglicerydy HDL-Ch Blood pressure Ciśnienie tętnicze Glucose Glikemia Metabolic syndrome cannot be diagnosed, but further measurements should be made if there is a family history of metabolic syndrome, T2DM, dyslipidemia, cardiovascular disease, hypertension and/or obesity Zespół metaboliczny nie może być rozpoznany, ale powinny być przeprowadzone dalsze badania, jeśli stwierdza się dodatni wywiad rodzinny w kierunku występowania zespołu metabolicznego, cukrzycy typu 2, dyslipidemii, chorób układu sercowo-naczyniowego, nadciśnienia tętniczego i/lub otyłości 150 mg/dl ( 1.7 mmol/l) <40 mg/dl (<1.03 mmol/l) systolic 130 mmhg / diastolic 85 mmhg skurczowe 130 mmhg i/lub rozkurczowe 85 mmhg 100 mg/dl ( 5.6 mmol/l) (If 5.6 mmol/l [or known T2DM] recommend an OGTT) 100 mg/dl ( 5.6 mmol/l) lub rozpoznana cukrzyca typu 2 Use existing IDF criteria for adults, i.e.: Central obesity (defined as waist circumference 94 cm for European men and 80 cm for European women, with ethnicity specific values for other groups plus any two of the following four factors: raised triglycerides: 1.7 mmol/l reduced HDL-cholesterol: <1.03 mmol/l (<40 mg/dl) in males and <1.29 mmol/l (<50 mg/dl) in females, or specific treatment for these lipid abnormalities raised blood pressure: systolic BP 130 or diastolic BP 85 mmhg, or treatment of previously diagnosed hypertension impaired fasting glycemia (IFG): fasting plasma glucose (FPG) 5.6 mmol/l ( 100 mg/dl), or previously diagnosed type 2 diabetes Kryteria jak dla osób dorosłych: Otyłość centralna (zdefiniowana jako obwód talii 94 cm dla Europejczyków i 80 cm dla Europejek oraz 2 z 4 następujących czynników zwiększone stężenie triglicerydów: 150 mg/dl (1,7 mmol/l) lub leczenie tego zaburzenia lipidowego zmniejszone stężenie HDL-Ch: <40 mg/dl (1,03 mmol/l) u mężczyzn i <50 mg/dl (1,29 mmol/l) u kobiet lub leczenie tego zaburzenia lipidowego podwyższone ciśnienie tętnicze: skurczowe 130 mmhg lub rozkurczowe 85 mmhg, lub leczenie rozpoznanego wcześniej nadciśnienia tętniczego zwiększone stężenie glukozy na czczo 100 mg/dl (5,6 mmol/l) lub wcześniej rozpoznana cukrzyca typu 2 WC waist circumference / obwód talii HDL-Ch high density lipoprotein cholesterol / cholesterol lipoprotein wysokiej gęstości T2DM type 2 diabetes mellitus / cukrzyca typu 2 OGTT oral glucose tolerance test / doustny test tolerancji glukozy 235

Szadkowska A., Pietrzak I., Szlawska J. et al. Abdominal obesity, metabolic syndrome in type 1 diabetic children and adolescents Pediatric Endocrinology, Diabetes and Metabolism 2009, 15, 4 236 In one of the most frequently used definition, National Cholesterol Education Program Adult Treatment Panel III (NCEP/ ATP III), abdominal obesity is still one of five components of metabolic syndrome (6). In 2005 IDF announced a new definition in which abdominal obesity is an obligatory component of metabolic syndrome (5). In this definition border values of waist circumference were significantly decreased in comparison with values admitted by NCEP/ATP III. Moreover, different border values were created for particular ethnic groups. In children and adolescents the problem with defining abdominal obesity is more significant. Usually 90 percentile for sex and age is considered to be a border value. However, a question should be asked which growth charts would be referential. In case of BMI used as a criterion of obesity, International Obesity Task Force created BMI growth charts according to Table II: Characteristics of the study group Tabela II: Charakterystyka grupy badanej Parametr Parameter Age [years] Wiek [lata] Duration of diabetes [years] Czas trwania cukrzycy [lata] Daily dose of insulin [j./kg/d] Dawka insuliny [j./kg/d] Mean±SD Średnia±SD Range Zakres 14.8±2.4 10.0-18.0 6.2±4.2 0.5-15.2 0.95±0.32 0.05-1.79 HbA 1 c [%] 8.0±1.5 5.3-13.9 Total cholesterol [mg/dl] Cholesterol [mg/dl] 175.6±35.2 114-296 HDL-cholesterol [mg/dl] 60.8±11.8 35-96 Triglycerides [mg/dl] Triglicerydy [mg/dl] Height [cm] Wzrost [cm] Weight [kg] Masa [kg] Body Mass Index (BMI) [kg/m 2 ] Wskaźnik masy ciała [kg/m 2 ] Waist circumference [cm] Obwód talii [cm] Waist/Height Ratio WHtR Wskaźnik talia/wzrost (liczba niemianowana) Systolic blood pressure SBP [mmhg] Skurczowe ciśnienie tętnicze SBP [mmhg] Diastolic blood pressure DBP [mmhg] Rozkurczowe ciśnienie tętnicze DBP [mmhg] Body Fat [%] Zawartość tłuszczu w organizmie [%] 97.3±64.8 33-508 164.7±12.0 134-195 59.3±15.1 29.4-103.7 21.6±3.8 14.7-33.0 74.4±9.7 56-110 0.45±0.05 0.37-0.66 116±15 86-161 68±10 45-98 21.9±7.14 9.5-43.5 egdr [mg/kg/min] 6.2±1.8 2.1-11.0 data from many countries. They notice the risk of reaching BMI 25 kg/m 2 for overweight and 30 kg/m 2 for obesity at the age of 18 year (15). Overweight is diagnosed with BMI above IOFT 25 and obesity above IOFT 30 curve. The use of these growth charts allows comparing data from different world regions. There are no unified recommendations for waist circumference border values. Most investigators insist that obtained value should be compared with growth charts for local population. There is, however, a question if using current population data in the society with increasing prevalence of obesity does not overstate 90 percentile and automatically abdominal obesity is more rarely diagnosed. According to all mentioned limitations, some authors consider Waist/Height Rate (WHtR) as a good indicator of abdominal obesity. Central obesity can be diagnosed if WHtR is higher than 0.5 and this value does not depend on age and sex. Measurement of anthropometric indices of abdominal obesity seems to be important, as they could be easily available and cheap parameters evaluating the risk of cardiovascular disease. Savva et al. and Bitsorri et al. proved that waist circumference and WHtR are better than BMI in predicting cardiovascular disease (16, 17). Brambilla et al., by estimating visceral fat mass in children and adolescents at the age of 7-17 years with the use of magnetic resonance, proved that waist circumference and WHtR can be much more sensitive than BMI in identification of children at risk of metabolic disorders development (18). Prevalence of obesity and abdominal obesity in childhood is significantly increasing in many countries (14, 19). Also among type 1 diabetic children and adolescents excessive body mass is much more common (20). This observation is the basis of accelerator hypothesis formulated by Wilkin in which insulin resistance is one of three accelerators leading to diabetes development. Increasing prevalence of obesity through intensification of insulin resistance corresponds with increase of the morbidity in type 2 as well as type 1 diabetes mellitus (21). Wskaźnik talia/wzrost Waist/height rate 0,54 0,52 0,50 0,48 0,46 0,44 0,42 0,40 0,38 0,36 0,34 0,32 F(8, 145)=1.1851, p=0.312 10 11 12 13 14 15 16 17 18 Age [years] / Wiek [lata] Fig. 1. WHtR for girl and boys Ryc. 1. Wartości WHtR dla dziewcząt i chłopców Girls / Dziewczęta Boys / Chłopcy

Szadkowska A., Pietrzak I., Szlawska J. i wsp. In the presented study, WHtR was used to estimate prevalence of abdominal obesity in type 1 diabetic children and adolescents. That made it possible to compare it with the prevalence of abdominal obesity in the general population, in 26 500 Lodz children at the age of 7-19 years, examined by Nawarycz et al. (14). They proved that WHtR value 0.5 could be used as a simplified and universal criterion of abdominal obesity prevalence for both sexes especially in case of adolescents (>13 years old). Abdominal obesity was twice more common in diabetic children than in general population. Similar tendency was observed in girls and boys. The lack of statistical significance is the result of a small number of examined diabetic children. Among diabetic children no significant differences in the prevalence of abdominal obesity between sexes were found. There were no statistically significant differences in absolute values of WHtR in particular years of age calendar of examined children as well. However, there was a correlation WHtR and components of metabolic syndrome as HDL-cholesterol concentration and blood pressure values. r = 0.59 p<0.001 45 40 35 30 Body Fat [%] 25 20 15 10 95% confidence 5 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 Waist/height rate / Wskaźnik talia/wzrost Fig. 2. Correlation between WHtR and Body Fat % Ryc. 2. Korelacja między wskaźnikiem WHtR a zawartością tłuszczu w organizmie (Body Fat%) Table III: Comparison of the prevalence of abdominal obesity in adolescents with type 1 diabetes mellitus and in the population of Lodz children at the age 14-19 years Tabela III: Porównanie częstości występowania otyłości brzusznej u młodzieży z cukrzycą typu 1 i w populacji dzieci łódzkich w wieku 14-19 lat Children at the age 14-18 years Diabetic children Dzieci chore na cukrzycę Lodz children p Dzieci w wieku 14-18 lat Dzieci łódzkie* Total / Ogółem n/n % 14/115 12.2 (CI95% 7.2-17.2) 849/12577 6.8 (CI95% 6.4-7.2) 0.030 Girls / Dziewczęta n/n % 6/51 11.8 387/6534 5.9 0.144 Boys / Chłopcy n/n % 8/64 12.5% 462/6043 7.6 0.224 * according to / według: T. Nawarycz. L. Ostrowska-Nawarycz (14) 237

Szadkowska A., Pietrzak I., Szlawska J. et al. Abdominal obesity, metabolic syndrome in type 1 diabetic children and adolescents Pediatric Endocrinology, Diabetes and Metabolism 2009, 15, 4 Table IV: Comparison of patients with and without metabolic syndrome Tabela IV: Porównanie pacjentów z i bez zespołu metabolicznego Parameter / Parametr Patients without MS / Pacjenci bez ZM n=151 Patients with MS / Pacjenci z ZM n=12 p Age [years] / Wiek [lata] 14.7±2.4 16.6±1.4 0.006 Duration of diabetes [years] / Czas trwania cukrzycy [lata] 6.2±4.2 6.2±3.4 0.981 Daily dose of insulin [j./kg/d] / Dawka insuliny [j./kg/d] 0.95±0.32 0.92±0.29 0.783 HbA 1 c [%] 8.0±1.5 8.7±1.8 0.090 BMI [kg/m 2 ] / Wskaźnik masy ciała [kg/m 2 ] 21.2±3.5 26.1±3.5 <0.001* Body fat [%] / Zawartość tłuszczu w organizmie [%] 21.2±6.8 30.2±5.7 < 0.001 * adjusted to sex and age / adjustowane do płci i wieku MS metabolic syndrome ZM zespół metaboliczny 238 Estimating WHtR relation with parameters describing the course of diabetes the only found correlation was with metabolic control of disease. No relation with diabetes duration or insulin dose was noticed. These results again show that 24-hour insulin requirement is not an ideal insulin resistance indicator. In this study the prevalence of metabolic syndrome according to IDF consensus definition was shown for the first time in type 1 diabetic children. The children older than 10 years were only included into the study as this is the youngest age when metabolic syndrome can be diagnosed according to IDF definition. One component of this definition was changed in this study. In general population, fasting hyperglycemia is indicator of insulin resistance and relative insulin deficiency. As all type 1 diabetic patients fulfill fasting hyperglycemia criterion, it was the reason for using egdr calculated according to worked out formula to evaluate insulin sensitivity (13). Prevalence of metabolic syndrome in adults as well as in children depends on the used definition (8). In NHANES 1999-2000 study metabolic syndrome was observed in 6.4% of children and adolescents at the age of 12-19 years (22). In Rodriquez-Morgan studies according to ATP III criteria metabolic syndrome was diagnosed in 6.5% of children at the age of 10-18 years (23). However, in the Bogalusa Heart Study metabolic syndrome occurred in 9% of children at the age of 4-17 years (24). In present the study the metabolic syndrome prevalence among type 1 diabetic children was 7.4% according to IDF. In American population of Caucasian children at the age of 12-17 years, metabolic syndrome prevalence estimated according to IDF criteria was 4.5% (25). Similarly to the study group, relation with the age of examined children was noticed. Among American children, the highest prevalence occurred in the group of children at the age of 16-17. Metabolic syndrome diagnosed according to NCEP criteria was more frequent in adult type 1 diabetic patients than in the general population as well (26). There are no studies according to IDF criteria. It seems that obligatory abdominal obesity criterion in IDF definition can decrease metabolic syndrome prevalence frequency in type 1 diabetic patients. It should be emphasized that disturbances such as dyslipidemia and increased values of blood pressure in this group of patients can also result from other reasons apart from insulin resistance. We should remember that in type 1 diabetic patients macroangiopathy risk is much more higher than among people without glucose tolerance disturbances. The independent risk factors for the development of cardiovascular disease are hypertension and hyperlipidemia. Probably among type 1 diabetic patients, previous definition that took into consideration insulin resistance, high blood pressure values and serum lipid concentration, could be a better indicator of cardiovascular risk. 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