Association of Physical Activity and Screen Time with Psychiatric Distress in Children and Adolescents: CASPIAN-IV Study.

BACKGROUND: There are limited studies about the association of physical activity (PA) and screen time (ST) with psychiatric distress (PD) among children and adolescents including Iranian populations. OBJECTIVE: We aimed to examine the independent and combined associations of PA and ST with PD among children and adolescents. METHOD: This school-based nationwide survey was carried out among 14 880 students (50.8% boys and 75.6% urban inhabitants), of age 6-18 years by cluster and the stratified multistage sampling method from 30 provinces of Iran. The students and their parents completed two sets of questionnaires obtained from Global School Health Survey with several questions about the PD. The time spent on watching TV/video and computer games and PA were assessed by self-administered validated questionnaires. RESULTS: The study had a participation rate of 90.6%. Of the studied students, 45.85%, 83.62%, 37.81% and 23.92% had depression, anger, insomnia and worthlessness, respectively. The prevalence of confusion, anxiety and worry was reported in 19.6%, 55.17% and 75.31% of the students, respectively. The combined effect of PA and that of ST showed that students with high PA and low ST had the lowest prevalence of PD, while the highest prevalence of these PD was observed among students with low PA combined with high ST (p < 0.05 for all). CONCLUSIONS: Increasing PA and reducing ST should both be considered for improving the mental health status of children and adolescents.

Is the association of weight disorders with perceived health status and life satisfaction independent of physical activity in children and adolescents? The CASPIAN-IV Study.

BACKGROUND: Physical activity (PA) and weight status have been suggested as predictors of life satisfaction (LS) and perceived health status (PHS). Therefore the present study aims to investigate and compare the impacts of body mass index (BMI) and PA on LS and PHS in a population of Iranian children and adolescents. MATERIAL AND METHODS: This study was conducted in 2011-12 as a nationwide population-based study among 14 880 students of age 6-18 years. Students were selected via a multistage cluster sampling method from 30 provinces of Iran. Information on demographics, PA, PHS and LS was obtained using the World Health Organization Global School-based Student Health Survey (WHO-GSHS) questionnaire. PA values were considered as low (<2 /week), moderate (2-4 h/week) and high (>2 h/week). RESULTS: The current study has a participation rate of 90.6% (50.8% boys). PA was significantly associated with both LS and PHS [odds ratio (OR), 1.37 in both), while in BMI, this association was significant for only PHS (in underweight: OR, 0.65; 95% CI, 0.57-0.75; in excess weight: OR, 0.82; 95% CI, 0.73-0.93). In the combined group of BMI-PA, the influence of PA prevailed over the impact of BMI on PHS and LS, and therefore, PA was found to be the stronger factor. CONCLUSION: Although BMI and PA could both significantly impact LS and PHS, the stronger influence of PA on LS and PHS suggests that upgrading the 'activity level' of children and adolescents should be underscored and included on the agenda, rather than merely focusing on their BMI and weight status.

Association of adolescents' weight status with life satisfaction: role of self, peers, family and school perception; the CASPIAN-IV Study.

BACKGROUND: Although many public health programs have focused on prevention and control of obesity, their efficacy mostly depends on personal factors including perception of weight and personal understanding of the concept of being overweight. This study aims to investigate the association of adolescent's weight status with life satisfaction and explore the role of self, peers, family and school perception in this association. METHODS: Data were obtained from the fourth school-based survey entitled "Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Disease" (CASPIAN) Study. This survey was conducted among 14,880 urban and rural students aged 6-18 years. Two sets of valid and reliable questionnaire obtained from Global School Health Survey (GSHS) were completed by students and their parents. The students' questionnaire had several questions including life satisfaction and the perception of weight, peers, family and school. RESULTS: The study had a participation rate of 90.6% including 50.8% boys and 76% urban residents. Significant differences existed in Body Mass Index (BMI) and in perception of weight among girls and boys. Moreover, the prevalence of depression and being bullied were higher among girls and boys, respectively. Significant association was documented between life satisfaction and all variables including perception of weight, peers, family and school; the only exception was for BMI (P<0.05). In addition, students with normal weight had significantly higher life satisfaction in comparison with their obese counterparts (P<0.05). CONCLUSIONS: The present study documented significant association between life satisfaction and perception of self, peer, family and school with the exception of BMI in both genders.

Association of healthy foods intake with anthropometric measures and blood pressure in a national sample of Iranian children and adolescents: the CASPIAN-IV Study.

BACKGROUND: This study aims to evaluate the association of consuming healthy foods with anthropometric measures and blood pressure (BP) in a national sample of Iranian children and adolescents. METHODS: This nationwide study was conducted in 2011-2012 among 13,486 students, aged 6-18 years, selected by multistage cluster sampling from 30 provinces. Weight, height, waist circumference (WC), hip circumference (HC), wais to height ratio (WHtR), waist to hip ratio (WHR), as well as systolic and diastolic blood pressures (SBP, DBP) were measured. Healthy foods were considered as four categories including fresh fruits, dried fruits, vegetables, and dairy products. The frequency consumption of each of these foods was recorded as daily, weekly, and seldom. RESULTS: The intake of fruits was significantly associated with anthropometric indices. Moreover, a significant association was found between vegetables consumption, DBP levels, and anthropometric indices (except for WHtR and WHR). Milk consumption was significantly associated with anthropometric indices (except for WHtR and WHR). The odds of general obesity among participants who seldom consumed dried fruits was less than those who consumed daily (OR: 0.84, 95%CI: 0.74-0.96). We did not find any significant association for the frequency of fresh fruits and vegetables consumption with obesity, abdominal obesity, DBP and SBP. CONCLUSIONS: Consumption of dried fruits was associated with general obesity in children and adolescents. These results highlight the effect of dietary quality and food choices on weight control in children and adolescents.

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.

Does the socioeconomic status affect the prevalence of psychiatric distress and violent behaviors in children and adolescents? The CASPIAN-IV study.

BACKGROUND: This nationwide study aims to investigate the prevalence of psychiatric distress and violent behaviors in a nationally-representative sample of Iranian children and adolescents according to the socioeconomic status (SES) of their living region. METHODS: In this study, 14,880 school students, aged 6-18 years, were selected from 30 provinces in Iran. The World Health Organization Global School-based Health Survey questionnaire was used. Data were compared at national and subnational levels according to the SES of the living region. RESULTS: Overall, 13,486 students (49.2% girls) with mean (SD) age of 12.47 (3.36) years completed the study. At national level, the prevalence of psychiatric distress ranged between 9 to 38%; the most and least prevalent psychiatric distresses were angriness (37.73%, 95% CI: 36.5-38.99) and confusion (8.65%, 95% CI: 8.04-9.29), respectively. Students living in regions with highest SES experienced angriness (41.24%, 95% CI: 38.94-43.59) more than in those from the regions with lowest SES (31.18%, 95% CI: 26.71-36.02). The prevalence of bullying, being bullied and physical fight was 17.56% (95% CI: 16.73-18.42), 27.36% (95% CI: 26.34-28.42), and 39.94% (95% CI: 38.69-41.20), respectively. The prevalence of violent behavior did not differ significantly in various regions of Iran. CONCLUSIONS: The relatively high prevalence of psychiatric distress in Iranian children and adolescents necessitates paying more attention to mental health of this vulnerable age group. Differences in the prevalence of such disorders according to the SES of the living area should be considered in planning evidence-based preventive programs and in international comparisons.

Is snack consumption associated with meal skipping in children and adolescents? The CASPIAN-IV study.

PURPOSE: The present inquiry set to assess the relationship between snack consumption and meal skipping in Iranian children and adolescents. METHODS: Overall, 14,880 students, aged 6-18 years, were selected via multistage cluster sampling method from rural and urban areas of 30 provinces of Iran. A validated questionnaire of food behaviors including questions on snacks consumption and taking/skipping meals was completed. Consuming and skipping meals and their related factors were reported in both crude and adjusted models. RESULTS: Overall, 13,486 students with a mean age of 12.47 ± 3.36 years completed the study (90.6% participation rate). Among them, 32.08, 8.89, and 10.90% skipped breakfast, lunch, and dinner, respectively. Compared to their counterpart groups, the frequency of meal skipping was higher in girls, urban inhabitants, and students in higher school grades (P < 0.05). Snack consumption was associated with an increased odds ratio of meal skipping in many types of snack groups. CONCLUSIONS: Meal skipping and snack consumption were frequent among Iranian children and adolescents. Evidence based interventions are proposed to improve the students' eating habits.

Socioeconomic inequality in oral health behavior in Iranian children and adolescents by the Oaxaca-Blinder decomposition method: the CASPIAN- IV study.

BACKGROUND: The present study set to describe the socioeconomic inequality associated with oral hygiene behavior among Iranian pediatric population. METHODS: A representative sample of 13486 school students aged 6-18 years was selected through multistage random cluster sampling method from urban and rural areas of 30 provinces in Iran. Principle Component Analyses (PCA) correlated variables summarized as socioeconomic status (SES). Association of independent variables with tooth brushing was assessed through logistic regression analysis. Decomposition of the gap in tooth brushing between the first and fifth SES quintiles was assessed using the counterfactual decomposition technique. To assess the relation between tooth brushing and each socioeconomic category, Concentration Index (C) and the slope index of inequality (SII) were used, representing the linear regression coefficient. RESULTS: The participation rate was 90.6 % (50.7 % boys and 75.6 % urban inhabitants). The mean age of participants was 12.47 ± 3.36 years. The frequency of tooth brushing increased across SES quintiles, prevalence of tooth brushing between the first and fifth quintile, under 20 % difference, increased from 58.22 (95 % CI: 56.24,60.20) to 78.61 (95 % CI: 77.00,80.24). Only 3 % of the difference is explained by the factors considered in the study, and 17 % remained unknown. Residence area, family size, and smoking status made a significant contribution to the gap between the first and last SE groups. Residence area [ -2.01 (95 % CI: -3.46, -0.55)] was along the maximum levels of gaps between SE categories. CONCLUSIONS: The findings revealed a socio-economic inequality in oral health behavior in Iranian children and adolescents. Also, factors influencing oral health are addressed to develop and implement complementary public health actions.

Accuracy of Blood Pressure-to-Height Ratio to Define Elevated Blood Pressure in Children and Adolescents: The CASPIAN-IV Study.

The aim of this study was to propose a simple practical diagnostic criterion for pre-hypertension (pre-HTN) and hypertension (HTN) in the pediatric age group. This study was conducted on a nationally representative sample of 14,880 students, aged 6-18 years. HTN and pre-HTN were defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥ 95 and 90-95th percentile for age, gender, and height, respectively. By using the area under the curve (AUC) of the receiver operator characteristic curves, we estimated the diagnostic accuracy of two indexes of SBP-to-height ratio (SBPHR) and DBP-to-height (DBPHR) to define pre-HTN and HTN. Overall, SBPHR performed relatively well in classifying subjects to HTN (AUC 0.80-0.85) and pre-HTN (AUC 0.84-0.90). Likewise, DBPHR performed relatively well in classifying subjects to HTN (AUC 0.90-0.97) and pre-HTN (AUC 0.70-0.83). Two indexes of SBPHR and DBPHR are considered as valid, simple, inexpensive, and accurate tools to diagnose pre-HTN and HTN in pediatric age group.

Regional disparity in hygienic behaviors of Iranian children and adolescents: The CASPIAN-IV study.

Background: This study aimed to assess the pattern of hygienic behaviors of Iranian children and adolescents at national and sub-national levels according to the socioeconomic status (SES) of their living region. Methods: Data were obtained from the fourth national school-based surveillance survey entitled, "CASPIANIV study" (2011-2012). It was conducted among 14,880 students, aged 6-18 years, who were selected by multistage random cluster sampling from 30 provinces in Iran. We used the World Health Organization Global School-based Student Health Survey (WHO- GSHS) questionnaire. Data were analyzed at national and subnational levels according to the SES of the living region. Results: Overall, 13,486 students (49.2% girls) with the mean (SD) age of 12.50 (3.36) years participated in this study (participation rate: 90.6%). At the national level, 67.21% of the participants had daily tooth brushing, the frequencies for always washing hands after using the toilet, washing hands before eating, and washing hands with soap in school were 85.61%, 56.53%, and 50.32%, respectively. The frequency of daily tooth brushing had no significant difference according to the SES of the living region. In all of the categories of washing hands, the West region (second high SES rank) had the highest frequency of hygienic behaviors (p<0.001). Conclusion: In general, the reported hygienic behaviors were at an acceptable level; however, a large comprehensive health-promoting plan should be considered for all children and adolescents at the national and subnational levels taking into account the disparities according to their SES.

The association of socioeconomic status of family and living region with self-rated health and life satisfaction in children and adolescents: The CASPIAN-IV study.

Background: Socioeconomic status (SES) is a major determinant of health inequality in children and adolescents. The aim of this study was to evaluate the association of SES of family and living region with self-rated health (SRH) and life satisfaction (LS) among children and adolescents. Methods: This study was a part of the fourth survey of a national surveillance program, which was conducted in 30 provinces of Iran in 2011-2012. LS and SRH were assessed by a questionnaire based on the World Health Organization-Global School-based student Health Survey (WHO-GSHS). Family SES was estimated using principal component analysis (PCA) and based on family assets, parental education and occupation, and type of school. Region SES was calculated using PCA and some variables including literacy rate, family assets and employment rate. Results: Out of 14,880 invited students, 13,486 (participation rate: 90.6%) completed the survey; of whom, 49.2% were girls, and 75.6% were from urban areas with the mean ± SD age of 12.47±3.36 years. In the multivariate model, SES of family and living region was associated with LS and good SRH. In the full models, in addition to all potential confounders, family and living region SES were included simultaneously. However, only the association of family SES with LS, and good SRH remained statistically significant. Conclusion: The effect of families' SES on SRH and LS is more important than regional SES. The presented patterns of SRH and LS may be useful in developing better health policies and conducting complementary studies in this field.

Association between body mass index and perceived weight status with self-rated health and life satisfaction in Iranian children and adolescents: the CASPIAN-III study.

PURPOSE: Adolescent obesity is a well-known worldwide issue with growing prevalence and complications. The concept of body image and complications of its misperception has been noted more recently. Life satisfaction (LS) and self-rated health (SRH) have also been known as independent morbidity and mortality factors. The objective of this study was to evaluate the associations of perceived weight status (body image) and actual body mass index (BMI), with LS and SRH in a nationally representative sample of a pediatric population in Iran, as a country located in the Middle East and North Africa region. METHODS: This nationwide population-based survey was conducted among 5,570 (2,784 female and 2,786 male) Iranian students, aged 10-18 years, living in urban and rural areas of 27 provinces, which were selected via multistage sampling method. Agreement between BMI and perceived weight status (underweight, about right and overweight/obesity) was assessed. Adjusted association between BMI and perceived weight status with LS and SRH was assessed using multiple logistic regressions after adjustment for potential confounders. RESULTS: Nearly 40 % of the participants misperceived their body image. Misperception as overweight or underweight was found to be associated with lower odds for both LS and SRH [overweight SRH OR 0.796 (95 % CI 0.647-980), underweight SRH OR 0.701 (95 % CI 0.588-0.835), overweight LS OR 0.884 (95 % CI 0.718-998), underweight LS OR = 0.676 (95 % CI 0.577-0.793)], whereas the association between actual BMI with LS and SRH was not statistically significant (P value > 0.05). CONCLUSION: A mismatch between BMI and body weight perception was found in this study. Moreover, LS and SRH were not related with BMI, but had negative association with body weight perception.

Joint Association of Active and Passive Smoking with Psychiatric Distress and Violence Behaviors in a Representative Sample of Iranian Children and Adolescents: the CASPIAN-IV Study.

BACKGROUND: Mental health and smoking have been receiving increasing attention in adolescents all over the world. Although some studies have assessed the independent association of active/passive smoking with mental health, joint association of active and passive smoking with mental health remains unclear. PURPOSE: This study was designed to evaluate the joint association of smoking status (active and passive smoking) with psychiatric distress and violent behaviors in Iranian children and adolescents. METHOD: In this national survey, 13,486 students, aged 6-18 years, living in rural and urban areas of 30 provinces of Iran were selected via multistage, cluster sampling method. Psychiatric distress (including worthless, angriness, worrying, insomnia, confusion, depression, and anxiety), violence behaviors (including bullying, victim, and physical fight), and smoking status (nonsmoker, only passive smoker, only active smoker, and active and passive smoker) were assessed. The questionnaire was prepared based on the World Health Organization Global School-based Student Health Survey (WHO-GSHS). Data were analyzed by the Stata package. RESULTS: Psychiatric distress and violent behaviors had linearly positive association with smoking status (p trend < 0.001). Compared to "nonsmoker" group, participants who were exposed to passive smoking besides active tobacco use were at increased risk of having angriness (odds ratio (OR) 2.55, 95 % confidence interval (CI) 1.86-3.48), worrying (OR 1.66, 95 % CI 1.24-2.20), and anxiety (OR 1.99, 95 % CI 1.52-2.61) and victim (OR 1.77, 95 % CI 1.34-2.33) and bully behaviors (OR 3.08, 95 % CI 2.33-4.07). CONCLUSION: The current findings suggest that active and passive tobacco smoking has synergistic effect on psychiatric distress. Since majority of smokers with psychiatric distress do not receive mental health services or counseling on smoking, strategies to address mental health problems and smoking prevention should be included as a part of school health services.

Association of 25-hydroxy Vitamin D levels with indexes of general and abdominal obesity in Iranian adolescents: The CASPIAN-III study.

BACKGROUND: This study aimed to determine the association of serum 25-hydroxy Vitamin D (25(OH)D) levels with measures of general and abdominal obesity in Iranian adolescents. MATERIALS AND METHODS: This nationwide cross-sectional study was conducted among 1090 students, aged 10-18 years, living in 27 provinces in Iran. Serum concentration of 25(OH)D was analyzed quantitatively by direct competitive immunoassay chemiluminescence method. Body mass index (BMI) and waist-to-height ratio (WHtR) were considered as measures of generalized and abdominal obesity, respectively. RESULTS: Study participants consisted of 1090 adolescents (51.9% boy and 67.1% urban residents) with mean age, BMI, and waist circumference of 14.7 (2.6) years, 19.3 (4.2) kg/m(2), and 67.82 (12.23) cm, respectively. The median serum 25(OH)D was 13.0 ng/mL (interquartile range: 20.6). Overall, 40% of participants were Vitamin D deficient, and 39% were Vitamin D insufficient. Serum 25(OH)D level was not associated with BMI and WHtR. CONCLUSION: We did not document any significant association between serum 25(OH)D level and anthropometric measures in adolescents. This finding may be because of considerably high prevalence of hypovitaminosis D in the study population.

A nationwide report on blood pressure of children and adolescents according to socioeconomic status: The CASPIAN-IV study.

BACKGROUND: Hypertension is a major leading factor for global burden of diseases. Blood pressure (BP) tracks from childhood to adulthood. So, it is important to investigate its aff ecting factors. In this study we aimed to compare the BP status in the Iranian pediatric population according to the socioeconomic status (SES) of their living area. MATERIALS AND METHODS: In this nationwide study, a representative sample of 14,880 students, aged 6-18 years was chosen by multistage random cluster sampling from 30 provinces in Iran. Anthropometric indices and BP were measured. A validated questionnaire, including the questions of the World Health Organization Global School-based Student Health Survey was completed. Findings were compared across the four regions of the country, categorized based on their elevating SES: Southeast, north-northeast, west, and central. RESULTS: Participants consisted of 13,486 children and adolescents, that is, a participation rate of 90.6%, composed of 49.2% girls and 75.6% urban residents. The mean (standard deviation) age of participants was 12.47 (3.36) years. The region with highest SES (central) had the lowest rate of high BP (HBP), that is, 3.0% (95% of confidence interval [CI]: 2.4-3.9), and the region with lowest SES (southeast) had the highest rate, that is, 7.4% (4.4-12.2). The mean (95% CI) values of systolic BP for the four regions from lowest to highest SES were 100.5 (99.6-101.3), 100.9 (100.3-101.4), 101.7 (101.3-102), and 101.7 (101.2-102.1) mmHg. The corresponding mean Diastolic BP values were as follows: 65.4 (64.6-66.1), 63.4 (62.9-63.8), 65.6 (65.3-65.8), and 64.4 (64.0-64.7) mmHg. CONCLUSION: We found significant differences in mean BP and the frequency of HBP according to the SES of the living area. Further studies are necessary to find the underlying factors resulting in such differences.

Weight disorders and anthropometric indices according to socioeconomic status of living place in Iranian children and adolescents: The CASPIAN-IV study.

BACKGROUND: Excess weight in children and adolescents is a multi-factorial phenomenon and associated with earlier risk of obesity-related diseases. This study aims to assess the prevalence of weight disorders and the mean values of anthropometric indices according to regional, socioeconomic, and urban-rural variations among Iranian children and adolescents. MATERIALS AND METHODS: This nationwide study was performed in 2011-2012 among a representative multi-stage cluster sample of 14,880 Iranian students aged 6-8 years. The World Health Organization (WHO) reference curves were used to define weight disorders. Abdominal obesity was defined as the waist-to-height ratio (WHtR) of more than 0.5. Iran was classified into four regions according to the socioeconomic status (SES). RESULTS: The mean (95% confidence interval) of body mass index (BMI), waist circumference (WC), and hip circumference (HC) was 18.8 (18.7, 18.9) kg/m(2), 67.0 (66.7, 67.3) cm, and 80.8 (80.3, 81.2) cm, respectively. The prevalence of underweight was 12.2%. A total of 9.7%, 11.9%, and 19.1% of students overweight, obese, and abdominally obese, respectively. The highest mean of BMI, WC, wrist circumference, HC, and WHtR were related to the second high SES (North-northeast) area (19.2 [18.8, 19.5], 68.3 [67.3, 69.4], 14.8 [14.7, 15.0], 82.6 [81.1, 84.0], and 0.464 [0.460, 0.468]). In contrast, the lowest SES (Southeast) region had the lowest mean of these anthropometric indices (17.6 [17.1, 18.2], 63.2 [61.7, 64.8], 14.5 [14.2, 14.8], 76.9 [74.9, 79.0], and 0.439 [0.434, 0.444]). CONCLUSION: We found considerable differences in the prevalence of anthropometric measures throughout the country by SES of the region. Health policy making and implementing health strategies should consider SES of regions.

Association of cardiometabolic risk factors and hepatic enzymes in a national sample of Iranian children and adolescents: the CASPIAN-III study.

OBJECTIVES: Elevated liver enzymes including alanine aminotransferase (ALT) and aspartate aminotransferase (AST) may be associated with metabolic syndrome (MetS) and cardiovascular disease. We investigated the association of cardiometabolic risk factors and liver enzymes in a nationally representative sample of Iranian children and adolescents. METHODS: The national study was conducted in the framework of the third survey of Childhood and Adolescence Surveillance and PreventIon of Adult Non-communicable Disease study. Subjects were 3948 students (1942 girls, 67.55% urban, mean age 14.7 ± 2.4 years) who were recruited by multistage random cluster sampling from 27 provincial counties in Iran. Physical examination and laboratory tests were conducted under standard protocols. RESULTS: Participants with elevated serum ALT had higher levels of almost all cardiometabolic risk factors than other participants; this difference was not significant for fasting blood glucose, total cholesterol, and diastolic blood pressure in both sexes, as well as low-density lipoprotein cholesterol in girls. Participants with generalized and abdominal obesity, MetS, elevated blood pressure, triglycerides, and total cholesterol had increased risk for elevated ALT; this risk remained significant after adjusting for sex and age. Low high-density lipoprotein cholesterol was found as a predictor for both elevated ALT (odds ratio 2.182, 95% confidence interval 1.533-3.105) and AST (odds ratio 2.022, 95% confidence interval 1.438-2.844) even after adjusting for all potential confounders. General (B 0.158, SE 0.030) and abdominal obesity (B 0.058, SE 0.029), MetS (B 0.231, SE 0.048), and triglycerides (B 0.094, SE 0.030) were associated with ALT:AST ratio after adjusting for all potential confounders (P < 0.001). CONCLUSIONS: We documented strong relations of elevated ALT, AST levels, and ALT:AST ratio with most cardiometabolic risk factors. This relation was independent of anthropometric indexes. Liver enzymes can be considered as a cardiometabolic risk factor from childhood, and as an additional component of the MetS.

Is air quality index associated with cardiometabolic risk factors in adolescents? The CASPIAN-III Study.

OBJECTIVE: This study aims to evaluate the association of air quality index (AQI) with cardiometabolic risk factors in a nationally representative sample of healthy adolescents. METHODS: This nationwide survey was conducted among a stratified multi-stage probability sample of students, aged 10-18 years, from 27 provinces of Iran. Those students with history of any acute or chronic diseases, any medication use, as well as active or passive smoking were not included to the current study. Dietary and physical activity habits were documented by valid questionnaires. Physical examination and blood sampling were conducted under standard protocols. AQI data were obtained from air pollution monitoring sites from the entire country by considering air pollutants concentration, which includes all provincial counties containing different clusters. RESULTS: The study participants consisted of 1413 students (48.8% boys) with a mean (SD) age of 14.81±2.48 years. The mean AQI level was 285.37±30.11 at national levels. After adjustment for confounding factors including age, sex, and anthropometric measures, as well as for dietary and physical activity habits, multiple linear regressions based on correlation of coefficients of the AQI with cardiometabolic risk factors showed significant positive correlations of AQI with systolic blood pressure, fasting blood glucose, total cholesterol, LDL-cholesterol, and triglycerides, as well as significant negative correlations with HDL-cholesterol. After adjustment for abovementioned confounding factors, binary logistic regressions analyses showed that AQI increased the risk of abnormal levels of some risk factors as elevated levels of systolic blood pressure, total cholesterol, and triglycerides. CONCLUSION: The associations of low air quality with some cardiometabolic factors in the current survey, although not strong, might be considered as an evidence of the adverse cardiometabolic consequences of exposure to air pollutants in the pediatric age group, and predisposing them to earlier development of non-communicable diseases.

Generalized or abdominal obesity: which one better identifies cardiometabolic risk factors among children and adolescents? The CASPIAN III study.

OBJECTIVES: We investigated the association of generalized and abdominal obesity with cardiometabolic risk factors in children and adolescents. METHODS: Data were obtained from a surveillance system entitled CASPIAN-III study in school students aged 10-18 years in Iran. Data of subjects with normal body mass index (BMI) or above (BMI ≥ 5th percentile) were analyzed. The associations of obesity with cardiometabolic risk factors were tested using logistic regression models. RESULTS: In the sample of 4641 children and adolescents, overweight/obese children were more likely to have metabolic syndrome and cardiometabolic risk factors compared with their normal weight counterparts. Among these parameters, elevated TG had the strongest association with degree of obesity (overweight: OR = 2.28 [95% CI 1.59-3.26]; obesity: OR = 5.63 [95% CI 4.27,7.43]). Combined generalized and abdominal obesity increased the risk of high blood pressure, elevated triglyceride and total cholesterol. CONCLUSIONS: Combined type of generalized and abdominal obesity is a predictor of cardiometabolic risk factors.

Reference curves of anthropometric indices in two national studies conducted among Iranian children in 2003-2004 and 2009-2010: The Caspian study.

BACKGROUND: Reference percentile curves are usually used as a screening tool to determine growth disorders. Anthropometric indices are population-dependent and may differ according to ethnicity, dietary pattern and lifestyle habits. This study aims to compare the curves of anthropometric measures obtained in two national studies conducted among Iranian children and adolescents in 2003-2004 and 2009-2010. MATERIALS AND METHODS: Anthropometric measures obtained in two nationwide surveys conducted in 10-18-year-old Iranian students were compared. Lambda-mu-sigma (LMS) Chart Maker Pro program was used to develop age- and gender-specific percentiles and to smooth and fit the model. RESULTS: In 2003-2004, the mean and standard deviation (SD) of body mass index (BMI) and waist circumference (WC) were 18.98 ± 3.81 kg/m(2) and 67.50 ± 11.05 cm in boys; and 19.44 ± 3.78 kg/m(2) and 66.55 ± 9.89 cm in girls, respectively. In 2009-2010, the corresponding figures were 19.16 ± 4.07 kg/m(2), 69.42 ± 11.43 cm, 19.63 ± 4.11 kg/m(2), and 67.29 ± 9.69 cm, respectively. Height curves did not show considerable changes in two studies. Comparison of two series of studies showed that the weight, BMI, WC, and waist-to-height ratio were lower in adolescent girls than boys especially in higher percentiles. Moreover, in both genders, weight, BMI, and WC percentiles decreased. CONCLUSION: The growth charts of Iranian children and adolescents aged 10-18 years have changed over 5 years. The reference growth curves change over time in the pediatric age group, repeated surveys should be conducted to update the age- and gender-specific reference curves in different populations.