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.

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.

Mapping the relative risk of weight disorders in children and adolescents across provinces of Iran: the CASPIAN-V study.

Background: This study aimed to find possible spatial variation in children's weight disorders and in predicting the spatial distribution. Methods: The study population of this ecological study consisted of 7-18-year-old students living in 30 provinces of Iran. We used Besag, York and Mollie (BYM) model, a Bayesian model, to study the relative risk (RR) of underweight and excess weight (overweight and obese). The model was fitted to data using OpenBUGS (3.2.1) software. Results: The highest RR of underweight was found in southeastern provinces. Whereas, the highest RR of excess weight was documented in northern, northwestern and capital provinces.Sistan-Balouchestan (RR=1.973; Bayesian confidence interval [BCI]: 1.682, 2.289), Hormozgan(RR=1.482; BCI: 1.239, 1.749), South Khorasan (RR=1.422; BCI: 1.18, 1.687) and Kerman(RR=1.413; BCI: 1.18, 1.669) had the highest RR of underweight. Mazandaran (RR=1.366; BCI:1.172,1.581), Gilan (RR=1.346; BCI: 1.15,1.562), Tehran (RR=1.271; BCI: 1.086,1.472) and Alborz (RR=1.268; BCI: 1.079,1.475) provinces are high risk regions for excess weight. Conclusion: The significant variations in geographical distribution of weight disorders are because of various sociodemographic and ethnic differences. The current findings should be considered in health policy making in different regions of the country.

Validity of anthropometric indices in predicting high blood pressure risk factors in Iranian children and adolescents: CASPIAN-V study.

Anthropometric indices have been used as indicators for predicting hypertension (HTN) in children and adolescents but it is not clear which anthropometric measures are a better index for identifying elevated blood pressure (EBP) risk factors in pediatric population. Body mass index (BMI), waist circumference (WC), weight-height ratio (WHR), a body shape index (ABSI) and blood pressure were measured in 14 008 children and adolescents aged 7-18 years in a national school-aged survey CASPIN V. Hypertension (HTN) was defined according to the 2017 American Academy of Pediatrics guidelines, using the 95th percentile. The predictive power of anthropometric indices for HTN risk factors was examined using receiver operating characteristic (ROC) analyses. Multivariate logistic regression analysis was used to compare areas under ROC curves (AUCs) among the four anthropometric indices. BMI, WC, WHR, and ABSI were significantly higher in adolescents than in children. EBP was more prevalent in boys (7.2%) than girls (5.5%), whereas the prevalence of HTN was higher in girls (11.3%) than boys 10.4%. Prevalence odds ratio was around 2 for BMI, WC, and WHR with AUCs scores of nearly 0.6 to predict EBP in both children and adolescents of both sexes. Thus, the ability of BMI z-score, WC, WHR or ASBI to identify Iranian children and adolescents at higher risk of EBP was week. WC, WHR or ASBI in combination with BMI did not improve predictive power to identify subjects at higher risk of EBP.

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

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

Dinner consumption and cardiovascular disease risk factors among a nationally representative sample of Iranian adolescents: the CASPIAN-III Study.

Introduction: This cross-sectional study aimed to assess the association between cardiovascular disease (CVD) risk factors and dinner consumption in a nationally representative sample of Iranian adolescents. Methods: The present study was conducted on 5642 adolescents aged 10-18 years old in 27 provinces in Iran. The subjects were included applying by multistage random cluster sampling. Participants who ate ≥5 dinners during a week were considered as a dinner consumer. Results: Among 5642 subjects, 1412 (25%) did not consume dinner. Dinner consumers were less likely to be overweight or obese (P < 0.001) and abdominally obese (P < 0.001) as well as to have an abnormal level of HDL-C (P = 0.02). Dinner skipper youths had a higher risk for overweight or obesity (odds ratio [OR]: 1.62; 95% CI: 1.39-1.89) and abdominal obesity (OR: 1.59; 95% CI: 1.36-1.85) which remained significant after adjusting confounding factors (P <0001). No relationship was observed between dinner consumption and the rest of the CVD risk factors, neither in crude nor in adjusted models. A higher proportion of dinner-consumer adolescents had no CVD risk factors in comparison to dinner-skipper subjects (31.1% vs. 28%). Conclusion: Eating dinner might be inversely associated with some CVD risk factors among Iranian adolescents. Further prospective studies will need to prove this theory.

Comparing the validity of continuous metabolic syndrome risk scores for predicting pediatric metabolic syndrome: the CASPIAN-V study.

Background The aim of this study was to compare the validity of various approaches to pediatric continuous metabolic syndrome (cMetS) scores including siMS scores (2 waist/height + fasting blood glucose [FBG]/5.6 + triglycerides [TG]/1.7 + systolic blood pressure [BP]/130 + high-density lipoprotein [HDL]/1.02), Z-scores, principal component analysis (PCA) and confirmatory factor analysis (CFA) for predicting metabolic syndrome (MetS). Methods This nationwide cross-sectional study was conducted on 4200 Iranian children and adolescents aged 7-18 years. The cMetS was computed using data on HDL, cholesterol, TGs, FBG, mean arterial pressure (MAP) and waist circumference (WC). The areas under the receiver operating characteristic curves (AUCs) were used to compare the performances of different cMetS scores. Results Data of 3843 participants (52.4% boys) were available for the current study. The mean (standard deviation [SD]) age was 12.6 (3) and 12.3 (3.1) years for boys and girls, respectively. The differences in AUC values of cMetS scores were significant based on the Delong method. The AUCs (95% confidence interval [CI]) were for Z-scores, 0.94 (0.93, 0.95); first PCA, 0.91 (0.89, 0.93); sum PCA, 0.90 (0.88, 0.92), CFA, 0.79 (0.76, 0.3) and also for siMS scores 1 to 3 as 0.93 (0.91, 0.94), 0.92 (0.90, 0.93), and 0.91 (0.90, 0.93), respectively. Conclusions The results of our study indicated that the validity of all approaches for cMetS scores for predicting MetS was high. Given that the siMS scores are simple and practical, it might be used in clinical and research practice.

Is dietary vitamin B intake associated with weight disorders in children and adolescents? The weight disorders survey of the CASPIAN-IV Study.

Background: Weight disorders are highly prevalent at the global level. Vitamin B groups are clearly involved in intracellular mechanisms, energy equation, and weight gain. The present study aims to evaluate the association of dietary vitamin B intake and obesity in a large pediatric population. Methods: This cross-sectional study was conducted among children and adolescents, aged 6-18years, living in urban and rural areas of 30 provinces of Iran. The BMI-for-age classifications were as follow: percentile <0.1, (emaciated), 0.1 ≤percentile <2.35 (thin), 2.35 ≤percentile≤84.1 (normal), 84.1

Risk-Taking Behaviors in Iranian Children and Adolescents: A Latent Class Analysis Approach: Caspian IV Study.

BACKGROUND: Risk taking behaviors have several negative consequences. This study aimed to identify the subgroups of students based on risk-taking behaviors and to assess the role of demographic characteristics, depression, anxiety, socioeconomic status (SES), physical inactivity and screen time on membership of specific subgroup. STUDY DESIGN: Cross-sectional study. METHODS: This nationwide survey was conducted in 2011-2012 among 14880 students, aged 6-18 yr, selected by multistage, cluster-sampling method from 30 provinces of Iran. The students completed two sets of anonymous and validated questionnaires, obtained from the World Health Organization-Global School Health Survey questionnaires. Latent class analysis was performed to achieve the study objectives. RESULTS: Overall, 13486 children and adolescents participated were enrolled (response rate 90.6%). They consisted of 50.8% boys, with a mean age of 12.47 ±3.36 year. The prevalence of physical fight, bullying, victimization, active smoking, passive hookah and passive cigarette smoking was 39.7%, 17.4%, 27.2%, 5.9%, 21.1 and 33.8%, respectively. Five latent classes were identified: (a) low risk (46.7%), (b) passive smoker (25.2%), (c violence and aggression taker with passive smoking (13.5%), (d) violence and aggression taker without passive smoking (10.8%) and (e) high risk (3.8%). Higher age (OR=1.41), being male (OR=5.21), depression (OR=4.58), anxiety (OR=3.38) and screen time (OR=3.11) were associated with high-risk class. CONCLUSION: The prevalence of some risk-taking behaviors among Iranian students is high. Our findings emphasize the importance of planning and evaluating preventive interventions by considering different high-risk behaviors simultaneously.

Logic Regression Analysis of Gene Polymorphisms and HDL Levels in a Nationally Representative Sample of Iranian Adolescents: The CASPIAN-III Study.

BACKGROUND: To investigate the associations of genetic polymorphism with high-density lipoprotein-cholesterol (HDL-C) levels in Iranian adolescents. METHODS: This multicentre study was conducted on 10 - 18 year-old students from 27 provinces in Iran. Logic regression approach was used to determine the main effects and interactions of polymorphisms related to HDL-C levels. RESULTS: The rs708272 polymorphism was significantly related to HDL-C levels. Moreover, rs708272 increased HDL-C levels and had a protective effect on HDL-C. The interaction of rs2230808 and rs5880 polymorphisms as well as the interaction of rs320 and rs708272 polymorphisms were associated with lower HDL-C levels. Furthermore, the interaction of rs320 and rs1801177 polymorphisms was associated with lower HDL-C levels. CONCLUSIONS: We found that not only single SNPs, but also interactions of several SNPs affect HDL-C levels. Given the high prevalence of low HDL-C in Middle Eastern populations, further genetic studies are required for detailed analysis.

Association of Glomerular Filtration Rate With Cardiometabolic Risk Factors in Iranian Adolescents: CASPIAN III Study.

INTRODUCTION: This study aimed to assess the association of glomerular filtration rate (GFR) with cardiometabolic risk factors in Iranian adolescents. MATERIALS AND METHODS: Data of the 3rd round of a school-based surveillance system entitled "Childhood and Adolescence Surveillance and PreventIon of Adult Non-communicable Disease (CASPIAN III)" study was used for this study. A sample of 367 adolescents aged between 10 and 18 years was randomly selected. Glomerular filtration rate was estimated using the original and the updated Schwartz equations. The association of GFR with anthropometric data, blood pressure, lipid profile, and blood glucose was assessed in boys and girls by age group. RESULTS: Of the participants, 50.4% were boys and 26.2% were from rural regions. In the age group of 14 to 18 years, the ratio of low- to high-density lipoprotein cholesterol was significantly lower in the girls than the boys (P < .001), and the girls had significantly higher triglyceride and FBG levels. Significant correlations were found between GFR and waist circumference (r = 0.150 and P = .009 with the original Schwartz; r = 0.190 and P < .001 with the updated Schwartz) and body mass index (r = 0.115 and P = .03 with the original Schwartz; r = 0.121 and P = .02 with the updated Schwartz).   Conclusions. The above findings showed that obese and overweight Iranian adolescents were more likely to have lower kidney function. Strategies to decline impaired kidney function may include prevention of obesity and central obesity in this population.

Interaction of lipoprotein lipase polymorphisms with body mass index and birth weight to modulate lipid profiles in children and adolescents: the CASPIAN-III Study.

CONTEXT AND OBJECTIVE: Interactions between body mass index (BMI), birth weight and risk parameters may contribute to diseases rather than the individual effects of each factor. However this hypothesis needs to be confirmed. This study aimed to determine to what extent variants of lipoprotein lipase (LPL) might interact with birth weight or body weight in determining the lipid profile concentrations in children and adolescents. DESIGN AND SETTING: Substudy of the third survey of a national surveillance system (CASPIAN-III Study) in Iran. METHODS: Whole blood samples (kept frozen at -70 °C) were randomly selected from 750 students aged 10-18 years. Real-time polymerase chain reaction (PCR) and high-resolution melt analysis were performed to assess S447X (rs328), HindIII (rs320) and D9N (rs1801177) polymorphisms. RESULTS: The AG/GG genotype in D9N polymorphism was associated with higher LDL-C (low-density lipoprotein cholesterol) and lower HDL-C (high-density lipoprotein cholesterol) concentration. Significant interactions were found for D9N polymorphism and birth weight in association with plasma HDL-C concentration, and also for D9N polymorphism and BMI in association with plasma triglyceride (TG) and HDL-C levels. HindIII polymorphism had significant association with birth weight for HDL-C concentration, and with BMI for TG and HDL-C levels. Significant interactions were found for S447X polymorphism and BMI in association with plasma TG and HDL-C concentrations. CONCLUSION: We found significant interactive effects from LPL polymorphisms and birth weight on HDL-C concentration, and also effects from LPL polymorphisms and BMI on TG and HDL-C concentrations.

Tobacco Use and Influencing Factors Among Iranian Children and Adolescents at National and Subnational Levels, According to Socioeconomic Status: The Caspian-IV Study.

BACKGROUND: Iran is facing an epidemiologic transition, with one of its features being the tendency towards smoking by adolescents. The findings of previous studies in Iran have shown that the pervasiveness of tobacco products among school students is high. No previous study has reported the prevalence and determinants of smoking in various socioeconomic statuses (SESs) and at the subnational level in Iran. OBJECTIVES: To compare the prevalence of smoking and the factors that influence the initiation and continuation of tobacco use in a nationally representative sample of Iranian adolescents living in different regions with diverse socio-demographic patterns. PATIENTS AND METHODS: This nationwide, cross-sectional study was conducted in 2011 - 2012 among 14,880 students, aged 6 - 18 years, selected by cluster sampling from 30 provinces. Anonymous questionnaires were completed about tobacco use and the main psychological determinants of initiation and continuation to smoke. The questionnaire was modeled on the world health organization global school-based student health survey (WHO-GSHS). The sub-national regions were defined by the criteria of geography combined with SES. According to this classification, the lowest to highest SESs were considered for the southeast, north-northeast, west, and central regions, respectively. Data were analyzed using the STATA statistical software package. RESULTS: Overall, 13,486 students completed this survey (participation rate of 90.6%). They consisted of 50.8% boys, 75.6% urban residents, with a mean age of 12.47 ± 3.36 years. According to the self-report of students, 2.6 % (3.5% of boys and 1.7% of girls) were current smokers, and5.9% (7.5% of boys and 4.2% of girls) had ever been smokers. The current use of tobacco was higher in participants aged 14 - 18 years (6.11%) than in those aged 10 - 13.9 years (1.18%) and 6 - 9.9 years (0.51%). Current and past tobacco use, respectively, had the lowest prevalence in the region with the lowest SES (2.2%, 3.7%) and the greatest prevalence in the highest SES region (4.3%, 8.9%). Entertainment was the most common reason for smoking initiation (83.65% of smokers) and continuation (77.01% of smokers), followed by feelings of pleasure, and enjoying the tobacco smell. These influencing factors did not differ significantly according to SES or gender. CONCLUSIONS: Smoking is a health problem for Iranian adolescents, and has a higher prevalence in areas with higher SES. Entertainment and feeling pleasure were the commonest reasons for initiation and continuation of smoking. Tobacco-control programs should begin from childhood and family-centered preventive counseling should be intensified in Iran.

Association of ghrelin with cardiometabolic risk factors in Iranian adolescents: the CASPIAN-III study.

Introduction: Current evidence suggests that ghrelin could contribute to the development of metabolic syndrome (MetS) in adults, but limited experience exists in adolescents. This study aims to explore the association of ghrelin levels with the MetS components among Iranian adolescents. Methods: In this case-control study, 32 adolescents with MetS and 148 healthy controls were selected randomly from the childhood and Adolescence Surveillance and Prevention of Adult Non communicable disease (CASPIAN-III) study. MetS was defined according to the Adult Treatment Panel III (ATP III) criteria modified for children and adolescents. Anthropometric measures (including body mass index [BMI], waist circumference [WC] and waist to height ratio [WHtR]), blood pressure (BP) and biochemical data (including fasting blood sugar [FBS], triglyceride [TG], high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol [LDL-C], total cholesterol [TC] and gerlin) were measured. Results: Total ghrelin level was significantly higher in students without MetS compared to those with MetS (748.89 ± 85.04 vs. 728.72 ± 90.36 [pg/mL]; P < 0.001). Significant negative correlations were seen between ghrelin levels and BMI, WC, WHtR, TG, and TC. Ghrelin had also relatively strong inverse correlations with FBS (r = -0.59, P< 0.001), LDL-C (r = -0.56, P < 0.001), and positive correlation with HDL-C (r = 0.60, P < 0.001). Compared with the children with MetS, in those without MetS, ghrelin was significantly associated with HDL-C and LDL-C. A decreasing trend was observed in the mean ghrelin level across increasing number of MetS components (P for trend <0.001). Conclusion: We observed a relationship between ghrelin concentration and MetS components in adolescents.

First National Report on Aminotransaminases' Percentiles in Children of the Middle East and North Africa (MENA): the CASPIAN-III Study.

BACKGROUND: By the current global obesogenic environment, non-alcoholic fatty liver disease is becoming an important health problem in the pediatric age group. OBJECTIVES: This study aimed to determine the first age-and gender-specific percentiles and upper limit normal limit (ULN) of alanine aminotransaminase (ALT) and aspartate aminotransaminase (AST) among a nationally-representative sample of children and adolescents in the Middle East and North Africa (MENA). The second objective was to determine the linear association of obesity indexes and age with serum ALT and AST levels. PATIENTS AND METHODS: This nationwide study was conducted among a representative sample of 4078 students aged 10-18 years, who were selected by multistage random cluster sampling from 27 provinces of Iran. ALT and AST were measured on fresh sera. Body mass index (BMI) was calculated as an index of generalized obesity, and waist- to- height ratio (WHtR) as an index of abdominal obesity. The age- and gender-specific percentiles of ALT and AST were constructed, and the 95th percentile of each enzyme was considered as the ULN. Gender-specific linear regression analysis was employed to examine the association of BMI or WHtR with the levels of ALT and AST. RESULTS: Data of ALT and AST were available for 4078 (2038 girls) and 4150 (2061 girls),respectively. Participants had a mean (SD) age of 14.71 (2.41).The ULN of ALT for boys, girls,and the total individuals were 36.00; 38.00; and, 37.00 U/L, respectively. In both genders, ALT and AST had linear association with age. The association with BMI was significant for ALT in both genders and for AST only in boys, the association of ALT with WHtR was significant in both genders; the corresponding figures were not significant for AST. CONCLUSIONS: The findings of the current study confirmed the current ULN value of 40 U/L commonly used for the pediatric age group. The linear association of indexes for generalized and abdominal obesity with ALT underscores the importance of timely prevention and control of childhood obesity.

Interaction of lipoprotein lipase polymorphisms with body mass index and birth weight to modulate lipid profiles in children and adolescents: the CASPIAN-III Study / Interação de polimorfismos da lipoproteína lipase com índice de massa corporal e peso ao nascer para modular o perfil lipídico em crianças e adolescentes: o estudo CASPIAN-III

CONTEXT AND OBJECTIVE: Interactions between body mass index (BMI), birth weight and risk parameters may contribute to diseases rather than the individual effects of each factor. However this hypothesis needs to be confirmed. This study aimed to determine to what extent variants of lipoprotein lipase (LPL) might interact with birth weight or body weight in determining the lipid profile concentrations in children and adolescents. DESIGN AND SETTING: Substudy of the third survey of a national surveillance system (CASPIAN-III Study) in Iran. METHODS: Whole blood samples (kept frozen at -70 °C) were randomly selected from 750 students aged 10-18 years. Real-time polymerase chain reaction (PCR) and high-resolution melt analysis were performed to assess S447X (rs328), HindIII (rs320) and D9N (rs1801177) polymorphisms. RESULTS: The AG/GG genotype in D9N polymorphism was associated with higher LDL-C (low-density lipoprotein cholesterol) and lower HDL-C (high-density lipoprotein cholesterol) concentration. Significant interactions were found for D9N polymorphism and birth weight in association with plasma HDL-C concentration, and also for D9N polymorphism and BMI in association with plasma triglyceride (TG) and HDL-C levels. HindIII polymorphism had significant association with birth weight for HDL-C concentration, and with BMI for TG and HDL-C levels. Significant interactions were found for S447X polymorphism and BMI in association with plasma TG and HDL-C concentrations. CONCLUSION: We found significant interactive effects from LPL polymorphisms and birth weight on HDL-C concentration, and also effects from LPL polymorphisms and BMI on TG and HDL-C concentrations.

RESUMO CONTEXTO E OBJETIVO: Interações entre índice de massa corporal (IMC), peso ao nascer e parâmetros de risco podem contribuir para doenças, em vez de efeitos individuais de cada fator. No entanto, essa hipótese precisa de confirmação. Este estudo visou determinar o quanto variantes de lipoproteína lipase (LPL) podem interagir com peso de nascimento ou peso corporal na determinação das concentrações do perfil lipídico em crianças e adolescentes. DESENHO E LOCAL: Sub-estudo da terceira pesquisa de sistema nacional de vigilância (Estudo CASPIAN-III) no Irã. MÉTODOS: Foram selecionadas aleatoriamente amostras de sangue total (mantidas congeladas a -70 °C) de 750 estudantes com idades entre 10-18 anos. Reação de polimerase em cadeia (PCR) em tempo real e análise de fusão de alta resolução foram realizados para avaliar polimorfismo de S447X (rs328), HindIII (rs320) e D9N (rs1801177). RESULTADOS: Genótipo AG/GG em polimorfismo D9N foi associado com concentração maior de LDL-C (colesterol do tipo lipoproteína de baixa densidade) e menor de HDL-C (colesterol do tipo lipoproteína de alta densidade). Interações significativas foram encontradas para polimorfismo D9N e peso ao nascer em associação com concentração plasmática de HDL-C, bem como para polimorfismo D9N e IMC em associação com níveis plasmáticos de triglicérides (TG) e HDL-C. Polimorfismo HindIII teve associação significativa com peso de nascimento para concentração de HDL-C, e com IMC para níveis de TG e HDL-C. Interações significativas foram encontradas para polimorfismo S447X e IMC em associação com concentrações plasmáticas de TG e HDL-C. CONCLUSÃO: Encontramos efeitos interativos significativos de polimorfismo LPL e peso de nascimento sobre concentração de HDL-C, bem como efeitos de polimorfismos LPL e IMC sobre concentrações de TG e HDL-C.