Socioeconomic inequality in violent behaviors, life dissatisfaction, and self-rated health in pediatric population: the CASPIAN-V study.

BACKGROUND: Bullying, being a victim of violent behaviors, life satisfaction (LS) and self-rated health (SRH) in children and adolescents, all have consistently been recognized as vital factors in school performance and future individual life. METHODS: This cross-sectional data secondary study was a part of the fifth Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable disease (CASPIAN-V) in 2015. A total of 14,400 students 7-18 years and their parents living in 30 provinces in Iran were studied. A validated questionnaire of the World Health Organization on Global School-based Health Survey (WHO-GSHS) was used to measure the outcomes and socioeconomic variables. Family's socioeconomic status (SES) was determined using principal component analysis (PCA). The crude and adjusted odds ratios (95% confidence interval (CI)) were estimated using multiple logistic regressions for each outcome. RESULTS: A total of 14,274 students completed the study, of whom 50.6% were boys. Overall, the prevalence of bullying, being a victim, life dissatisfaction (LDS), and poor SRH among students was 35.6, 21.4, 21.1, and 19.0%, respectively. In multiple-logistic regression analysis (Adjusted OR, (95%CI), students with an illiterate father and mother (1.60, (1.25-2.04), 1.28, (1.03-1.61), unemployed father (1.58, (1.29-1.81)), and one-parent family (1.32, (1.05 - 1.64) had a higher odd of Poor-SRH. Besides, a family size larger than four members (1.14, (1.03-1.25), and low-SES (1.35, (1.15-1.56), and illiteracy of the mother (1.64, (1.30-2.08) had a direct association with LDS. Mother illiteracy also increased the odds of bullying (1.77, (1.45-2.16) and being a victim (1.58, (1.26-1.98). CONCLUSIONS: Some socioeconomic variables can be proposed as the statistically significant attribution of bullying and being a victim, LDS, and Poor-SRH in children and adolescents.

Trend of passive smoking and associated factors in Iranian children and adolescents: the CASPIAN studies.

BACKGROUND: It is well documented that, similar to active smokers, passive smokers are also at an increased risk of developing non-communicable diseases, and it could impose high financial costs on the healthcare system. This study aimed to evaluate the trend of passive smoking and related determinants during the three phases of a school-based surveillance program. METHODS: This is a secondary study using the national data obtained from three phases of the surveillance program entitled The Childhood and Adolescence Surveillance and Prevention of Adult Noncommunicable Disease (CASPIAN) study, conducted from 2008 to 2014 on Iranian children and adolescents living in urban and rural areas of 30 provinces in Iran. Participants were selected by cluster multistage sampling method. RESULTS: Overall, the study participants consisted of 33,288 students (50.5% boys) with a mean (± SD) age of 12.8 ± 3.2 years. The passive smoking rate was significantly increased from 35.6% in 2008 to 43.2% in 2015 among children and adolescents. According to the multivariate logistic regression, father's university education, mother's employment, life satisfaction, and socioeconomic status had a protective role regarding second-hand smoke exposure. In contrast, the father's self-employment had a positive role in increasing the rate of passive smoking. CONCLUSION: Considering the increasing trend of passive smoking and its considerable adverse health effects, it is necessary to implement large-scale public interventions to reduce the rate and hazards of exposure to tobacco smoke.

Determinants of life satisfaction and self-rated health in Iranian children and adolescents: a structure equation model.

BACKGROUND: Life satisfaction (LS) and self-rated health (SRH) are related with health outcomes. It is expected that these items are also related to healthy behaviors. Therefore, this study was conducted in order to find out the main determinants of LS and SRH in nationwide representative sample of Iranian children and adolescents. METHODS: This study was performed on 13,834 students aged 7-18 years who were selected by multistage, stratified cluster sampling method from 30 provinces of Iran. Life satisfaction and SRH were assessed through a questionnaire based on World Health Organization-Global School-based Student Health Survey protocols. Path analysis was applied to evaluate the relationships among the study variables using the structural modeling. RESULTS: Life satisfaction was directly affected by age (- 0.037 in boys & -0.028 in girls); sedentary time (0.055 in boys & 0.048 in girls); school satisfaction (0.249 in boys & 0.250 in girls); and well-being (0.186 in boys & 0.176 in girls). Self-rated health was directly affected by LS (0.28 in boys & girls) and school satisfaction (0.21 in boys & 0.22 in girls); and indirectly affected by age (- 0.046 in boys & -0.017 in girls); sedentary time (- 1.99 in boys & -0.145 in girls); family size (- 0.005 in boys & -0.014 in girls); and socio-economic status (0.015 in boys & 0.058 in girls). CONCLUSIONS: This study indicated that school satisfaction had the greatest positive direct effect on both LS and SRH.

Association of Vitamin D Concentrations with subjective health complaints in children and adolescents: the CASPIAN-V study.

BACKGROUND: Vitamin D deficiency (VDD) is recognized as a global pandemic. Identification, any association between VDD and subjective health complaints (SHC), can be helpful to realize critical mechanisms and improve psychological and somatic symptoms. Given few studies published on this issue and the importance of its clarification, the main objective of this study was to examine the association between VDD and the SHC in children and adolescents. METHODS: In this national cross-sectional study, 2596 Iranian children and adolescents aged 8-18 years were included. Data on SHC, anthropometric indices, physical activity, and serum levels of vitamin D were collected. Logistic regression models (crude, adjusted) were applied to examine the association between the VDD and the SHC. Statistical analysis was performed using STATA version 11. P-values< 0.05 were considered as statistically significant. RESULTS: Serum levels of vitamin D in approximately 70% of Iranian children and adolescents were lower than 30 ng/mL. Among the SHC, irritability (40.9%) and feeling anxiety (33.7%) were the most prevalent ones. Multiple complaints in students with the VDD was 2.5 times greater than those with sufficient vitamin D concentrations (p <  0.001). Compared to the reference group, the strongest association was found between vitamin D status and difficulties in getting to sleep (OR: 2.5, 95%CI: 1.18, 3.53, p <  0.001). CONCLUSION: VDD was observed in the considerable percentage of the study population. There were no significant differences between the two gender groups. In addition, there were significant associations between vitamin D status and most of the somatic and psychological symptoms, particularly for getting to sleep. It seems national interventional programs for vitamin D supplementation or food fortifications can be helpful.

Association of dietary acid load with anthropometric indices in children and adolescents.

PURPOSE: High dietary acid load (DAL) may have an influence on anthropometric indices. Given that there was no study on the association between DAL and anthropometric indices children and adolescents, the current study was aimed to examine the association between DAL and anthropometric indices in Iranian children and adolescents. METHODS: Students aged 6-18 years were recruited using a multi-stage, cluster sampling method from 30 provinces of Iran. Dietary intake was assessed through a validated food frequency questionnaire. Height (Ht), weight (Wt), neck circumference (NC), waist circumference (WC), wrist circumference, and hip circumference (HC) were measured. WC-to-HC ratio (WHR), WC-to-Ht ratio (WHtR), body mass index (BMI) z-score, tri-ponderal mass index (TMI), and parental BMI were computed. Potential renal acid load (PRAL) and net endogenous acid production (NEAP) were used to estimate DAL. The association between DAL and anthropometric indices was evaluated using linear regression models. RESULTS: In total, 5326 students (46.92% girls), with mean (standard deviations (SD)) age of 12.50 (3.14) years participated in the study (response rate: 98.13%). After adjusting for confounders, there was a significant association between NEAP and NC (P < 0.05). Also, an inverse association was observed between PRAL and NEAP with parental BMI (P < 0.05). CONCLUSION: Our findings showed a direct association between diet-induced acid load and NC and an inverse association between DAL indices and parental BMI. More well-designed clinical studies are warranted to confirm our results and the underlying mechanisms. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.

A comparison between body mass index and waist circumference for identifying continuous metabolic syndrome risk score components in Iranian school-aged children using a structural equation modeling approach: the CASPIAN-V study.

PURPOSE: The purpose of this study was to investigate the association of anthropometric indices with continuous metabolic syndrome (cMetS) risk score components in a large population-based sample of children and adolescents. METHODS: This multi-centric study was performed on 3843 students aged 7-18 years who were selected by multistage, stratified cluster sampling method from 30 provinces of Iran. Demographic, anthropometric and biochemical factors were obtained and standardized residuals (z-scores) were calculated for MetS components. A structural equation modeling approach was applied to evaluate the relationships among the study variables and to implement the subsequent structural modeling. RESULTS: The mean age of the participants (52.3% boys) was 12.4 ± 3.05 years. Standardized scores of body mass index (ZBMI) and waist circumference (ZWC) had a direct effect on standardized scores of mean arterial pressure (ZMAP) (0.23 and 0.24 in boys and 0.22 and 0.23 in girls, respectively) and triglyceride (ZTG) (0.07 and 0.04 in boys and 0.02 and 0.06 in girls, respectively), but the effect of ZWC was stronger than ZBMI on these variables. Age, socioeconomic status and sedentary behaviors showed a positive direct effect on ZWC (0.01, 0.05 and 0.07 in boys and 0.05, 0.08 and 0.002 in girls, respectively). These variables induced indirect effects on cMets risk score components through ZWC. CONCLUSION: The magnitude of association between WC and continuous metabolic syndrome risk score components was higher compared to BMI in school-aged children, emphasizing on paying more attention to central obesity in childhood. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.

Seroprevalence of Bordetella pertussis among a nationally representative sample of Iranian pediatric population: The childhood and adolescence surveillance and prevention of adult noncommunicable disease-V study.

BACKGROUND: Pertussis is a vaccine-preventable respiratory infection and seroepidemiology of the infection could be a marker of the pertussis immunity in a population. In many countries, despite vaccination coverage, high prevalence of pertussis has been observed. The present study aimed to evaluate the immunoglobulin G (IgG) antibody against pertussis and the role of demographic and anthropometric variables on the immunity rate in the Iranian pediatric population to evaluate the impact of existing immunization program in order to envisage future vaccination strategies to prevent infection. METHODS: In a cross-sectional multi-centric study, 1593 samples of the students aged 7-18 years, who had been enrolled in a national survey (Childhood and Adolescence Surveillance and Prevention of Adult Noncommunicable disease-V), were randomly selected and tested for IgG antibody against Bordetella pertussis (BP) by enzyme-linked immunosorbent assay. The age, gender, education, residency, geographical region, and body mass index (BMI) were extracted from the questionnaires of the COSPIAN-Survey. Multiple logistic regression models were used to assess the associations between the variables with the IgG antibody against BP. Data were presented by odds ratio (OR), 95% confidence interval (95% CI) and P values (P): (OR [95% CI]; P). RESULTS: Subjects were consisted of 774 boys and 750 girls, with a mean (standard deviation) age of 12.39 (3.03) years. Overall, BP seroprevalence was 59.8%. There were higher BMI values in seronegative ones versus seropositive (18.62 ± 4.07 vs. 18.15 ± 3.94, P = 0.041, 95% CI = 0.23 [0.02-0.92]). However, the categorized BMI for age was not significantly associated with IgG levels (0.27 [0.25-0.29]; 0.27). BP seroprevalence was not significantly different between geographical regions (0.06 [0.05-0.07]; 0.06), genders (1.17 [0.93-1.47]; 0.18), area of residence (1.07 [0.82-1.4]; 0.61), and educational levels (0.94 [0.75-1.19]; 0.62). CONCLUSION: IgG antibody against pertussis was not detected in nearly 40% of the subjects who had history of vaccination against pertussis. It is recommended to monitor the incidence of pertussis in high-risk populations closely and administer a booster dose of acellular pertussis vaccine in adolescents.

Is frequency of potato and white rice consumption associated with cardiometabolic risk factors in children and adolescents: the CASPIAN-V study.

BACKGROUND: This study evaluated the association of frequency of potato and rice consumption with cardiometabolic risk factors in children and adolescents. METHODS: This nationwide cross-sectional survey was conducted on 14,400 children and adolescents. Fasting blood was obtained from a sub-sample of 4200 randomly selected students. Physical examination and laboratory tests were conducted under standard protocols. Metabolic Syndrome (Mets) was defined based on the Adult Treatment Panel III criteria modified for the pediatric age group. The self-reported frequency consumption of white rice and potato was reported on a daily or non-daily basis. RESULTS: The participation rate for the whole study and for blood sampling were 99 and 91.5%, respectively. Overall, 49.4% of the participants were girls while 50.6% were boys. The frequency of daily consumption of white rice and potato was 84.4 and 21.3%, respectively. In the multivariable linear regression model, daily consumption of potato increased body mass index (ß: 0.05, SE: 0.20, p = 0.010), waist (ß: 0.63, SE: 0.24, p = 0.008), and hip circumferences (ß: 0.62, SE: 0.26, p = 0.019). Moreover, in the multivariable logistic regression, daily consumption of potato was significantly associated with an increased risk of overweight (OR: 1.21, 95% CI: 1.04-1.39, P = 0.012). The potato and rice consumption had no statistically significant association with other cardiometabolic risk factors. CONCLUSIONS: Daily consumption of potato was significantly associated with higher anthropometric measures, whereas rice consumption had no statistically significant association with cardiometabolic risk factors. Future research to examine the possible obesogenic effects of intake of potato on children and adolescents is recommended.

Determinants of childhood blood pressure using structure equation model: the CASPIAN-V study.

BACKGROUND: Childhood hypertension is a predictor of later diseases, increases the risk for cardiovascular morbidity and mortality in adulthood and results in major economic burdens. The purpose of this study was to investigate the direct and indirect effect of anthropometric, socioeconomic and lifestyle factors on blood pressure (BP) in a large population-based sample of children and adolescents using a path analysis. METHODS: This multi-centric nationwide study was performed on students aged 7-18 years. Anthropometric indices and blood pressure were measured by standard methods and demographic data, socioeconomic status, dietary habits and health related behaviors were obtained using validated questionnaires. Path analysis was applied to evaluate the relationships among the study variables and to implement the subsequent structural modeling. RESULTS: Totally, 7235 students (50.6% boys; the mean age 12.3 ± 3.1 years) were assessed. Systolic and diastolic BP positively correlated with age (r = 0.35 and 0.26; respectively), BMI (r = 0.06 and 0.04; respectively) and WC (r = 0.05 and 0.03; respectively). According to path analysis, age had significant direct effect on BMI, WC, and BP (ß = 0.035, 0.043 and 0.345; respectively), which was greater for BP. BMI and WC had the greatest direct effect on BP (ß = 0.05 and 0.03; respectively). Education level, subjective health complaints, health-related behaviors and dietary habits had positive direct effects on BP (ß = 0.036, 0.030, 0.018 and 0.017; respectively). Socioeconomic status and positive changes in diet had negative indirect effect on BP (ß = - 0.001 for both). CONCLUSION: Our findings strengthen the importance of weight and body composition in BP control. It is suggested to improve diet and health related behaviors especially in families with low socioeconomic position.

Comparison common equations for LDL-C calculation with direct assay and developing a novel formula in Iranian children and adolescents: the CASPIAN V study.

BACKGROUND: Hypercholesterolemia is a common dyslipidemia that leads to atherosclerosis. It is proved that early stages of atherosclerosis begins in early stages of life. In several studies, widespread prevalence of dyslipidemia in children is reported. So, assessment of lipid profile in children and adolescence is necessary for early diagnosis of dyslipidemia. Laboratory methods for measuring LDL are not available and economical. So, in some laboratories Friedwald method is used to determine LDL level. But, the preciseness of this method is not acceptable. Further, the preciseness of this method was not assayed in children and adolescence. So, it seems that assaying the preciseness of different methods is necessary. METHODS: The methodology of this work is on the basis of findings of the Caspian V study. This study was conducted in 30 provinces of Iran during 2015. The population of this work was rural and urban students aged 7-18 years old. The level of total cholesterol (TC), HDL, LDL, and TG were measured using laboratory methods. The average and variances values were determined for each group of data using SPSS. Further, LDL values were calculated with a new formula introduced in this work. A comparison was made between the new formula and the other methods. RESULTS: In the present study, we found that compare to four common formulas, Friedwald was the best equation to estimate LDL-C concentrations in Iranian children and adolescents and the new formula was the next accurate equation. The strongest correlation between Friedwald and the new equation was found for those with 15-18 years old. CONCLUSION: Considering the cut-off points of TG (100 mg/dL), we observed the strongest correlation between Friedwald equation and direct assay and the weakest one was for Ahmadi formula in subjects with either greater or lower TG concentrations. Furthermore, we found that Anandraja equation had the most sensitivity (89.5%), while the most specificity was dedicated to the new formula (98.9%).

Reference values for lipid profile in Iranian children and adolescents: the CASPIAN-V study.

BACKGROUND: We aimed to develop the age- and sex-specific reference values for lipid profile of Iranian pediatric population. METHODS: Fasting lipid profiles of 3843 participants, aged 7 to 18 years, were extracted from a surveillance survey on Iranian children and adolescents living in 30 provinces across the country. RESULTS: The mean (SD) age of participants was 12.3(3.1) years, and 52.3% of them were boys. Significant differences were observed between genders comparing the levels of triglyceride (TG) (P = 0.04), total cholesterol (TC) (P = 0.02), low-density lipoprotein- cholesterol (LDL-C) (P = 0.01), and non-high-density lipoprotein cholesterol (non-HDL-C) (P = 0.03). In both genders, TG levels increased with age in the 75th and higher percentiles. Among boys, TC showed a decreasing trend at all percentiles and all age groups. In girls, TC levels increased with age at all percentiles except for the 75th and 90th percentiles. Among boys, the levels of LDL-C and HDL-C decreased with age in all percentiles. However, LDL-C and HDL-C concentrations increased up to the 50th percentile in girls and then decreased with age. The non-HDL-C level decreased in the 50th and higher percentiles among boys and in the 90th and 95th percentiles among girls. The TG/HDL-C ratio increased with age at all percentiles in boys. In girls, TG/HDL-C ratio increased with age in the 50th and higher percentiles. CONCLUSIONS: Based on the observed differences, it seems necessary to determine age- and sex-specific cut-off values for lipid parameters of children and adolescents in different populations.

Association of Sunlight Exposure with Sleep Hours in Iranian Children and Adolescents: The CASPIAN-V Study.

We aimed to assess the association of sunlight exposure with sleep duration and sleep onset time in children. Data were obtained from the fifth survey of a national school-based surveillance program in Iran. Sunlight exposure time, sleep duration, sleep onset time, physical activity time, mental health status and frequency of consuming coffee and tea were recorded. Overall, 14 274 students aged 7-18 years were recruited. Sleep duration was associated positively with sex, age, body mass index and physical activity, as well as with sunlight exposure and negatively with the consumption of coffee and tea. Higher physical activity, exposure to sunlight and mental status score in children exposed to sunlight via their face, hands, arms and feet, reduced the likelihood of sleep onset time after midnight (odds ratio (OR) = 0.909, 0.741 and 0.554 respectively). Daily exposure to sunlight may increase sleep duration and advance the sleep onset time in children and adolescents.

Association of fruit and vegetable intake with meal skipping in children and adolescents: the CASPIAN-V study.

BACKGROUND: There are few studies on the association of main meal consumption with fruit and vegetable intake. This study aims to assess the relation between skipping main meals and fruit and vegetable intake in children and adolescents. METHODS: This multi-centric cross-sectional study was conducted in 30 provinces of Iran. This study was conducted in the framework of the fifth survey of a national surveillance program entitled Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Disease study (CASPIAN- V). 14,440 school students aged 7-18 years were assessed. Logistic regression analyses were used to evaluate the association between frequency of fruit and vegetable intake with skipping main meals. RESULTS: Overall, 14,274 students completed the study (99% participation rate). Their mean (SD) age was 12.3 (3.2) (53% were aged 6-12), 50.6% of them were boys, and 71.3% lived in urban area. In multivariate logistic regression model, statistically significant associations were found between skipping main meals and low fruits and vegetables intake. Skipping breakfast was associated with vegetables intake [OR = 1.19(95% CI 1.02-1.38)] and fruits intake [OR = 5.33(95% CI 4.46-6.37)]. Skipping lunch was associated with vegetables intake [OR = 1.61(95% CI 1.29-1.96)] and fruit intake [OR = 9.11(95% CI 6.55-12.67)]. Skipping dinner was associated with vegetables intake [OR = 1.52 (95% CI 1.15-2.01)] and fruits intake [OR = 2.21(95% CI 1.64-2.97)]. CONCLUSIONS: In this study, low frequency of fruit and vegetable intake was associated with skipping main meals. The results highlight the importance of promoting regular meal consumption with increase in the intake of fruit and vegetables among children and adolescents. LEVEL OF EVIDENCE: Level V.

Association of Dietary Inflammatory Index with anthropometric indices in children and adolescents: the weight disorder survey of the Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Disease (CASPIAN)-IV study.

This study aimed to assess the relationship between the Dietary Inflammatory Index (DII®), a validated tool for evaluating diet-associated inflammation, and anthropometric indices in children and adolescents. This multicentre survey was conducted on 5427 school students selected via multistage cluster sampling from thirty provinces of Iran. This survey was conducted under the framework of the weight disorders survey, which is part of a national surveillance programme entitled Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable Diseases-IV. For calculating the DII scores, twenty-five dietary factors were obtained from a validated 168-item FFQ. Height, weight, wrist circumference, neck circumference (NC), waist circumference (WC) and hip circumference (HC) were measured. BMI z-score, waist circumference:hip circumference ratio (WHR), waist circumference:height ratio (WHtR) and parental BMI were computed. Linear regression models were used to evaluate the association of DII and anthropometric indices. Significant trends were observed across quartiles of DII score for all anthropometric indices in all participants (P <0·05), except for WHR and WHtR. After adjustment for potential confounders, the multiple linear regression analysis for each anthropometric index revealed that participants in the highest DII quartile had higher BMI z-score, WC, HC and parental BMI compared with those in the first (or lowest) quartile. In summary, we found that a pro-inflammatory diet was associated with higher BMI z-score, wrist circumference, NC, WC, HC and parental BMI. The large sample size of the present study may influence the statistical significance of observed associations. Hence, the findings should be clinically interpreted with caution.

Utility of waist circumference-to-height ratio as a screening tool for generalized and central obesity among Iranian children and adolescents: The CASPIAN-V study.

BACKGROUND: Waist-to-height ratio (WHtR) is regarded as a simple anthropometric index for evaluating central adiposity because of its independence of age, gender, and ethnicity. OBJECTIVE: The purpose of this study was to determine the optimal WHtR cutoff value in screening obesity and to compare it with other obesity indicators including body mass index (BMI) and waist circumference (WC) in Iranian children and adolescents. METHODS: This large survey was conducted on 14 274 Iranian children and adolescents as a national school-based surveillance study (CASPIAN) in 2015. The receiver operating characteristic curve analysis was performed to estimate the optimal cut-off points of WHtR for the prediction of general and central obesity. The area under curve (AUC) was used to compare the ability of WHtR cut-off points, BMI and WC percentiles to discriminate students with and without obesity according to age and sex. RESULTS: The optimal WHtR cutoff value for predicting general obesity was 0.49 and 0.48 for boys and girls, respectively and for central obesity according to WC ≥ 90th percentile was 0.50 for both genders. AUC values of WHtR for predicting general and central obesity were 87% and 96%, which indicates its strong predictive ability. For central obesity, the AUCs of WHtR were superior to those of WC percentiles. The kappa agreement coefficient was 0.55 between WC ≥ 90th percentile and WHtR ≥ 0.5. CONCLUSIONS: The WHtR ≥ 0.5 as a simple and useful screening tool is better than WC, for predicting general and central obesity in different age and sex groups of Iranian children and adolescents.

Association of screen time and physical activity with health-related quality of life in Iranian children and adolescents.

BACKGROUND: Health-related quality of life (HRQoL) is a multidimensional concept with significant effects and children and adolescence; while physical activity (PA) and screen time (ST) have been suggested as its probable predictors. Present study aims to investigate the association of PA, ST and their combination, with HRQoL in a nationally-representative sample of Iranian children and adolescents. METHODS: As for the estimated sample size, 25,000 students aged 6-18 years were selected via multi-stage cluster sampling from 30 provinces of Iran. Sociodemographic data was obtained by using the questionnaire of the World Health Organization-Global school based student health survey (GSHS). Persian Pediatric Quality of Life inventory (PedsQL) and Physical Activity Questionnaire for the pediatric age group (PAQ-A) were applied for evaluating HRQoL and PA, respectively. PA scores 1-1.9 and 2-5 were respectively considered as low and high PA. The average duration of time spent on watching TV and leisure time computer use were considered as ST behaviors. ST of less than 2 h was considered low. RESULTS: Out of 25,000 invited individuals, 23,043 students (mean age: 12.5) completed the study (response rate: 92.17%). In linear regression models, ST duration had significant inverse association with total QoL (ß: - 0.49, p < 0.05). PA showed positive significant associations with HRQoL total score (ß: 1.8, p < 0.05). Joint association of PA and ST revealed the strongest association of "high PA-low ST" category with total HRQoL (ß: 2.2, p < 0.05); while "high PA-high ST" showed better total HRQoL score (ß: 1.3) compared to "low PA-low ST" subgroup. CONCLUSION: Both PA and ST are significantly and independently associated with HRQoL in Iranian children and adolescents; while the adverse effect of prolonged ST could be diminished by a high PA.

Use of green spaces, self-satisfaction and social contacts in adolescents: A population-based CASPIAN-V study.

BACKGROUND: A growing body of evidence has associated contact with green spaces with improved mental health and wellbeing in adults. Social contacts has been postulated as a potential mechanism underlying such effects. However, the available evidence on the association between green spaces and self-satisfaction and also the mediatory role of social contacts in health benefits of green spaces in adolescents is still very scarce. We aimed to evaluate the association of time spent in different types of green spaces with self-satisfaction and social contacts in adolescents. We also investigated the mediatory role of social contacts in the association of green space use and self-satisfaction. METHODS: This cross-sectional study was based on a population-representative sample of 10,856 adolescents (10-18 years old) living in urban and rural districts across 30 provinces of Iran (2015). Data on the time spent in green spaces (separately for parks, forests and private gardens), self-satisfaction, social contacts (number of friends and time spent with friends), and socio-demographic characteristics were obtained through questionnaires from parents and children. Logistic mixed effects models with recruitment centre as the random effect were developed to estimate associations adjusted for relevant covariates. RESULTS: More time spent in green spaces was associated with improved self-satisfaction and social contacts. While for the self-satisfaction, there was no indication for effect modification by sex, socioeconomic status (SES), and urbanity, we observed stronger associations for older adolescents (> 14 years old). For social contacts, we found indications for stronger associations for boys, older adolescents, those residing in rural areas, and those from lowest and highest SES groups. Social contacts could explain more than half of the association between green spaces use and self-satisfaction. CONCLUSIONS: Our observed enhanced self-satisfaction and social contacts associated with more time spent in green spaces could provide policymakers with measures to improve mental wellbeing of adolescents. Further studies are required to replicate our findings in other populations with different climates, cultures and lifestyles.

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.

Health-Related Quality of Life according to the Socioeconomic Status of Living Areas in Iranian Children and Adolescents: Weight Disorders Survey.

BACKGROUND: Health-related quality of life (HRQoL) has become a major concern in the field of children's health research. We assessed HRQoL among Iranian children and adolescents according to the socioeconomic status (SES) of their living region. METHODS: Via multistage cluster sampling from rural and urban school students aged 6 to 18 years, this nationwide study was conducted from 2011 to 2012. HRQoL was assessed using the adolescent core version of the Pediatric Quality of Life questionnaire. Through survey data analysis methods, the data were compared according to the SES of the living region, sex, and the living area. RESULTS: Overall, 23043 students participated in the survey (participation rate=92.2%). The mean age of the participants was 12.55±3.31 years. Boys accounted for 50.8% of the study population, and 73.4% were from urban areas. At national level, the mean of the HRQoL total score was 81.7 (95% CI: 81.3 to 82.1) with a mean of 83.5 (95% CI: 83.0 to 84.1) for the boys and 79.8 (95% CI: 79.1 to 80.5) for the girls. The highest and the lowest scores, respectively, belonged to social functioning (90.0 [95% CI: 89.7 to 90.3]) and emotional functioning (78.2 [95% CI: 77.7 to 78.7]). The highest total HRQoL score belonged to the second highest SES region of the country (mean=83.1; 95% CI: 82.5 to 83.7). The association between total HRQoL and the score of all the subscales and SES in the living area was statistically significant (P<0.001). CONCLUSION: The results of the present study showed that in the children and adolescents, SES was associated with HRQoL. Accordingly, HRQoL and the related SES differences should be considered one of the priorities in health research and health policy.

Is single-child family associated with cardio-metabolic risk factors: the CASPIAN-V study.

BACKGROUND: In the present study, the association of the cardio-metabolic risk factors and the status of single-child family were studied in a national representative sample of Iranian children and adolescents. METHODS: This cross sectional study was conducted as the fifth round of "Childhood and Adolescence Surveillance and PreventIon of Adult Non- communicable disease" surveys. The students' questionnaire was derived from the World Health Organization-Global School Student Health Survey. Using survey data analysis methods, data from questionnaires'; anthropometric measures and biochemical information analyzed by logistic regression analysis. RESULTS: Overall, 14,274 students completed the survey (participation rate: 99%); the participation rate for blood sampling from students was 91.5%. Although in univariate logistic regression model, single child students had an increased risk of abdominal obesity [OR: 1.37; 95% CI: 1.19-1.58)], high SBP [OR: 1.58; 95% CI:1.17-2.14)], high BP [OR: 1.21; 95% CI:1.01-1.45)] and generalized obesity [OR: 1.27; 95% CI:1.06-1.52)], in multiple logistic regression model, only association of single child family with abdominal obesity remained statistically significant [OR: 1.28; 95% CI:1.1-1.50)]. Also in multivariate logistic regression model, for each increase of a child in the family the risk of abdominal obesity [OR: 0.95; 95% CI: 0.91-0.97), high SBP [OR: 0.88; 95% CI: 0.81-0.95)] and generalized obesity [OR: 0.95; 95% CI: 0.91-0.99)] decreased significantly. CONCLUSION: The findings of this study serve as confirmatory evidence on the association of cardio-metabolic risk factors with single-child family in children and adolescents. The findings of study could be used for better health planning and more complementary research.