M. Mümtaz Mazıcıoğlu

Insulin Resistance in Obese Children and Adolescents: HOMA-IR Cut-Off Levels in the Prepubertal and Pubertal Periods

Objective: Childhood obesity is associated with an increased risk for insulin resistance. The underlying mechanism for the physiological increase in insulin levels in puberty is not clearly understood. The aim of the present study was to determine the cut−off values for homeostasis model assessment for insulin resistance (HOMA−IR) in obese children and adolescents according to gender and pubertal status. Methods: Two hundred and eight obese children and adolescents (141 girls, 127 boys) aged between 5 and 18 years were included in the study. The children were divided into prepubertal and pubertal groups. A standard oral glucose tolerance test (OGTT) was carried out in all children. A total insulin level exceeding 300 μU/mL in the blood samples, collected during the test period, was taken as the insulin resistance criterion. Cut−off values for HOMA−IR were calculated by receiver operating characteristic (ROC) analysis. Results: In the prepubertal period, the rate of insulin resistance was found to be 37% in boys and 27.8% in girls,while in the pubertal period, this rate was 61.7% in boys and 66.7% in girls. HOMA−IR cut−off values for insulin resistance in the prepubertal period were calculated to be 2.67 (sensitivity 88.2%, specificity 65.5%) in boys and 2.22 (sensitivity 100%, specificity 42.3%) in girls, and in the pubertal period, they were 5.22 (sensitivity 56%, specificity 93.3%) in boys and 3.82 (sensitivity 77.1%, specificity 71.4%) in girls. Conclusions: Since gender, obesity and pubertal status are factors affecting insulin resistance, cut−off values which depend on gender and pubertal status, should be used in evaluation of insulin resistance. Conflict of interest:None declared.

Neck circumference as a novel parameter to determine metabolic risk factors in obese children.

Eur J Clin Invest 2012; 42 (6): 623–630

Reference Body Mass Index Curves for Turkish Children 6 to 18 Years of Age

AIM To determine reference body mass index (BMI) curves for Turkish children 6 to 18 years old and to compare with BMI in other countries. METHODS A cross-sectional study conducted in Kayseri, Turkey. A total of 5,727 children (2,942 girls, 2,785 boys) aged between 6 and 18 years were selected to construct a reference curve using LMS method. RESULTS BMI age reference charts of Turkish children were constructed. The 50th percentile curve of Turkish girls is lower than Italian and Turkish girls in The Netherlands but higher than Iranian girls. The 50th percentile curve of Turkish boys is lower than Italian and Turkish boys in The Netherlands and similar to Iranian boys after 13 years of age. CONCLUSION BMI references of Turkish children are lower than in South East Europe, UK and North American populations, but higher than in Central European and Scandinavian countries.

Married men’s opinions and involvement regarding family planning in rural areas

As men play a prominent role in reproduction, it is therefore extremely useful to assess and encourage them to be involved in contraception, particularly in developing countries, where contraceptive goals have not been reached. This study was carried out in Kayseri, Turkey, in order to determine the attitudes and behavior of married men concerning family planning. A questionnaire was presented to 123 married men. In our study, 91.9% of men approved of family planning, but only 54.4% actually used any contraceptive methods; 66.7% of the men said that the decision should be a joint one, 66.4% wanted to limit their family size. Approximately one fourth of the men had never heard of voluntary sterilization. No one in the study group was aware of the mini-pill, diaphragm or Norplant. In the study group, 26.8% of the men did not want their wives to use intrauterine devices and 31.7% of them did not agree with women using the contraceptive pills. Among those unwilling to use a condom (46.3%), 70.1% stated that it might interrupt intercourse. If a contraceptive pill for males could be used, 25.2% of members of the group would be prepared to use it. Only 17.5% men in the study group had contacted a doctor or a health foundation to obtain information. The main sources of family planning information were TV/radio, followed by friends and newspapers/magazines. In order to encourage mens involvement in family planning, the use of mass media and continual training programs, to try to reach both men and women, could be very useful.

The relationship between sleep duration and obesity in Turkish children and adolescents

Aim: To determine the relationship between sleep duration and obesity in Turkish children and adolescents.

Percentiles and mean values for neck circumference in Turkish children aged 6-18 years.

Aim:  To provide neck circumference (NC) percentiles and mean values for Turkish children and to investigate their significance in clinical and epidemiological use.

Waist Circumference and Mid−Upper Arm Circumference in Evaluation of Obesity in Children Aged Between 6 and 17 Years

Objective: The purpose of this study was to determine the cut−off values for waist circumference (WC) and mid−upper arm circumference (MUAC) and to assess their use in screening for obesity in children. Methods: Anthropometric measurements of a total of 2621 boys and 2737 girls aged 6−17 years were analyzed. WC and MUAC values were compared with ROC analysis using body mass index (BMI) cut−off values of the International Obesity Task Force (IOTF) and using WC≥ 90th percentile.for MUAC. Results: In both genders, except for boys and girls in the 6−year age group and post−pubertal boys, the differences between area under curve (AUC) values for WC and MUAC were not significant, indicating that both indices performed equally well in predicting obesity. Sensitivity was suboptimal through age groups 6−9 years in the boys and sensitivity was suboptimal at 6, 7,14 and 17 years both in boys and girls. Conclusions: We conclude that MUAC can be a useful parameter in screening obesity and body fat distribution in children and, can be applied in epidemiological studies and in clinical practice. Conflict of interest:None declared.

Cross-sectional reference values for mid-upper arm circumference, triceps skinfold thickness and arm fat area of Turkish children and adolescents.

The aim of the study was to establish cross-sectional reference values for the mid-upper arm circumference (MUAC), triceps skinfold thickness (TSF) and arm fat area (AFA) of Turkish children and adolescents. In total 5,553 students aged between 6 and 17 years were selected by a multistage sampling method from schools representing city centre, rural and urban areas of Kayseri, Central Anatolia. The MUAC and TSF were measured, and the arm muscle area, arm area, AFA and fat percentage (%) were calculated. The LMS method was employed to calculate the MUAC, TSF and AFA curve parameters. The MUAC, TSF, AFA and fat percentage in each age group were significantly higher in girls than in boys. In boys, the TSF 50th percentile ranged from 7.6 mm at 17 years to 9.0 mm at 11 years; whereas in girls this ranged from 9.4 mm at 6 years to 14.6 mm at 17 years. The MUAC 50th percentile ranged from 17.0 to 23.6 cm in boys, and from 15.6 cm to 20.9 cm in girls. The AFA 50th percentile measurements ranged from 4.5 cm at 6 years to 5.8 cm at 12–14 years in boys; and ranged from 7.2 cm at 6 years to 14.8 cm at 17 years in girls. The percentile distribution was more disperse towards higher TSF and AFA values in boys than in girls.

All-age relationship between arm span and height in different ethnic groups

The objective of the present study was to establish multiethnic, all-age prediction equations for estimating stature from arm span in males and females. The arm span/height ratio (ASHR) from 13 947 subjects (40.9% females), aged 5–99 years, from nine centres (in China, Europe, Ghana, India and Iran) was used to predict ASHR as a function of age using the lambda, mu and sigma method. Z-scores for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC in 1503 patients were calculated using measured height and height calculated from arm span and age. ASHR varied nonlinearly with age, was higher in males than in females and differed significantly between the nine sites. The data clustered into four groups: Asia, Europe, Ghana and Iran. Average predicted FEV1, FVC and FEV1/FVC using measured or predicted height did not differ, with standard deviations of 4.6% for FEV1, 5.0% for FVC and 0.3% for FEV1/FVC. The percentages of disparate findings for a low FEV1, FVC and FEV1/FVC in patients, calculated using measured or predicted height, were 4.2%, 3.2% and 0.4%, respectively; for a restrictive pattern, there were 1.0% disparate findings. Group- and sex-specific equations for estimating height from arm span and age to derive predicted values for spirometry are clinically useful. Height estimated from arm span, age and ethnic group allows clinically valid classification of spirometric data http://ow.ly/y8kiK

Body mass index percentiles for Turkish children aged 0-84 months

Background: Reference body mass index (BMI) percentiles are needed to follow secular changes in Turkish children aged 0–84 months. Obesity prevalence in this age group is also not well documented. Aim: The aim of this study was to determine BMI percentiles and the prevalences of overweight and obesity in Turkish children aged 0–84 months. The authors also tried to compare actual BMI status with World Health Organization (WHO) standards. Subjects and methods: This study used data from the Anthropometry of Turkish Children aged 0–6 years (ATCA-06) study. This cross-sectional study, conducted from September 2009 to May 2010 in Kayseri, Turkey, included 2683 children (1359 girls, 1324 boys) aged 0–84 months. Centile curves were constructed using the LMS method. Results: It was found that BMI percentiles of Turkish children were higher than WHO standards in early childhood. The overweight and obesity prevalences were identical in both genders, 10.0% and 4.9%, respectively. Conclusion: This study provides both BMI reference values and prevalence figures for overweight and obesity in children aged 0–84 months, residing in Kayseri city, in Turkey. It is believed that these data can be of use in following secular changes as well as for comparisons with international standards.