Prevalence of Growth Disorders in a Nationally Representative Sample of Iranian Adolescents According to Socioeconomic Status: The CASPIAN-III Study

Worse becomes the worst: obesity inequality, its determinants and policy options in Iran

Background

This tracked obesity inequality and identified its determinants among the population of Iran. In addition, it examined the impact of implemented policies on these inequalities.

Methods

This study was performed in two phases. First, we conducted a rapid review of the disparity in obesity prevalence in Iran. Then we investigated the main determinants of this inequality in a qualitative study. In addition, we examined Iran's policies to deal with obesity from the perspective of equality. We conducted 30 Semi-structured interviews with various obesity stakeholders selected through a purposive snowball sampling method between November 25, 2019, and August 5, 2020. In the inductive approach, we used the content analysis method based on the Corbin and Status framework to analyze the data using MAXQDA-2020. The consolidating criteria for reporting a Qualitative Study (COREQ-32) were applied to conduct and report the study.

Results

Inequalities in the prevalence of obesity in terms of place of residence, gender, education, and other socioeconomic characteristics were identified in Iran. Participants believed that obesity and inequality are linked through immediate and intermediate causes. Inequality in access to healthy foods, physical activity facilities, and health care are the immediate causes of this inequality. Intermediate factors include inequality against women, children, and refugees, and inequality in access to information, education, and financial resources. Policymakers should implement equity-oriented obesity control policies such as taxing unhealthy foods, subsidizing healthy foods, providing healthy and free meals in schools, especially in disadvantaged areas, and providing nutrient-rich foods to low-income families. Also, environmental re-engineering to increase opportunities for physical activity should be considered. Of course, for the fundamental reduction of these inequalities, the comprehensive approach of all statesmen is necessary.

Conclusion

Obesity inequality is a health-threatening issue in Iran that can prevent achieving human development goals. Targeting the underlying causes of obesity, including inequalities, must be considered.

Economic inequality in prevalence of underweight and short stature in children and adolescents: the weight disorders survey of the CASPIAN-IV study

Objective

The aim of this study was to determine the determinants of socio-economic inequality in the prevalence of short stature and underweight in Iranian children and adolescents.

Methods

This cross-sectional nationwide study was conducted on 36,486 participants, aged 6-18 years. This school-based surveillance (CASPIAN- IV) program and its complementary part on weight disorders evaluation was conducted in urban and rural areas of 30 provinces in Iran. In addition to physical examination, a validated questionnaire was completed from students and their parents. Socio-economic status (SES) was determined using principal component analysis, and was classified in quintile scale. Inequality in the prevalence of underweight and short stature was assessed using concentration (C) index and slop index of inequality (SII) by the Oaxaca-Blinder decomposition method.

Results

The prevalence (95% CI) of underweight and short stature at national level was 10.89 (10.55, 11.23) and 4.15 (3.94, 4.38), respectively; it had a downtrend from the lowest to highest SES quintile. Furthermore, the value of C for underweight and short stature was negative, i.e. inequality was in favor of high SES groups. Moreover, the prevalence gap of underweight and short stature in the first and fifth quintiles of SES was 6.58% and 5.80%, respectively. The highest proportion of this gap was explained by living area. In the multiple logistic model, odds of underweight and short stature were significantly lower in individuals with higher SES. Compared to boys, odds of underweight were decreased in girls, whereas odds of short stature were increased in them. Odds of underweight and short stature were increased in participants from rural areas than in urban areas. With increasing age, the odds of underweight and short stature decreased significantly.

Conclusion

The results of this study showed that inequality in the prevalence of short stature and underweight was in favor of high SES groups. Moreover, living area was one of the most important determinants that explained this inequality. Therefore, this issue needs to be considered in health promotion policies.

Decomposition of socioeconomic inequality in growth disorders to its determinants in pediatric population: the CASPIAN IV study

Purpose

The current study aims to evaluate socioeconomic inequality in growth disorders and its determinants in Iranian children and adolescents.

Methods

In this nationwide cross-sectional survey, 14,880 students aged 6-18 years were selected through multistage cluster sampling method from urban and rural areas of 30 provinces of Iran in 2011. Socioeconomic status (SES) was calculated using principle component analysis. Socioeconomic inequality in growth disorders (including; underweight, excess weight, overweight, general obesity, abdominal obesity, and short stature) was assessed using concentration index (C) and slope index of inequality (SII). The Oaxaca Blinder decomposition method was used to determine determinants of this inequality.

Results

Totally, 13,486 students participated in this study (participation rate: 90.6%), comprising 50.8% boys and 75.6% urban inhabitants. Their mean age was 12.47 ± 3.36 years with no significant gender difference. The prevalence of excess weight, overweight, and general and abdominal obesity increased linearly as SES increased, and the prevalence of underweight and short stature decreased linearly as SES increased. The C index for underweight and short stature was negative, which suggests that inequality was in favor of high SES groups, and regarding overweight, excess weight, general and abdominal obesity, the index was positive, indicating that inequality was in favor of in low SES groups.

Conclusion

Our findings show a considerable inequality in prevalence of growth disorders in Iranian children and adolescents. These findings provide practical information for health policies and programs.

Longitudinal association between body mass index and physical activity among adolescents with different parental risk: a parallel latent growth curve modeling approach

Background

Data available on the association between physical activity (PA) and body mass index (BMI) in different periods of life is controversial. Using a parallel latent growth curve modeling (LGCM) approach, the current study aimed to investigate the influence of daily PA on adolescents’ BMI over a 12 year follow-up, taking into account their parental risk.

Method

Participants comprised 1323 adolescents (53.5% girls), aged 12–18 years who had participated in the baseline phase of Tehran Lipid and Glucose Study (TLGS) (2001–2003), and were followed for an average period of 12 years. Physical activity, including leisure time and occupational activities, was assessed using the reliable and validated Iranian version of the Modifiable Activity Questionnaire (MAQ). Weight and height were objectively measured in order to calculateBMI.Atwo-step cluster analysis was conducted to classify parents into two high- and low-risk clusters. Parallel LGCM was fitted to estimate cross-sectional, prospective and parallel associations, which assessed the longitudinal association between simultaneous changes in PA and BMI during the study period. Analyses were stratified by gender and parental clusters.

Results

A rising trend of BMI per 3 years was observed in boys 1.39 kg.m²(95% CI; 1.32, 1.48) and girls 0.9 kg.m²(95% CI; 0.82, 0.98), as well as in the low risk 1.11 kg.m²(95% CI; 1.03, 1.18) and high-risk 1.12 kg.m²(95% CI; 1.03, 1.22) clusters. Moreover, a positive prospective association between PA at baseline and BMI change over the 12 year follow-up, was observed in adolescents in the low-risk parental cluster 0.27(95% CI; 0.14, 0.41) indicating that higher levels of PA at baseline may lead to greater BMI in adolescents over time. However, examining longitudinal parallel association between simultaneous changes of PA and BMI per 3 years revealed adverse associations for adolescents in the low-risk parental cluster − 0.07 (95% CI; − 0.13, − 0.01) and in boys − 0.06 (95% CI; − 0.11, − 0.01).

Conclusion

Despite a positive prospective association between BMI and PA at baseline, there was a weak inverse parallel association between these variables over time, particularly in boys and adolescents with low parental risk. These findings imply the potential role of other influential factors indetermining adolescents’ weight status which need to be considered in the future plannings.

A multivariate multilevel analysis of the risk factors associated with anthropometric indices in Iranian mid-adolescents

BACKGROUND

The present study was conducted to jointly assess some specific factors related to body fat measures using a multivariate multilevel analysis in a representative sample of Iranian mid-adolescents.

METHODS

This study was conducted among 2538 students (1286 boys) aged 14-20 years old, who were randomly selected among 16 public high schools by multi-stage random sampling procedure from all education districts of Shiraz, Iran. Data on demographic characteristics, family history of obesity, physical activity, socio-economic (SES) variables and screen time were collected. Height, weight, triceps (TST), abdominal (AST), and subscapular (SST) skinfold thickness were measured and their body mass index (BMI) was calculated. A multivariate multilevel approach was used to analyze the factors associated with obesity measures of the TST, AST, SST at the child and district levels.

RESULTS

In this study, the prevalence of overweight and obesity was estimated to be 10.2 and 5.1%, respectively. Overall, the major portion of the total variance in TST (97.1%), AST (97.7%), and SST (97.5%) was found at the child level. The results of multivariate multilevel method revealed that being girls, having a family history of obesity, and SES were significantly associated with increasing of three body fat measures (all the p-values were less than 0.05). There were significant positive associations between moderate to vigorous physical activities with AST and SST (for AST: β =2.54, SE = 1.40, p = 0.05; for SST: β =2.24, SE = 1.20, p = 0.05). Compared to children in 14-16 age group, children in age group 16-18 years had less TST (β = - 0.67, SE = 0.34, p = 0.04). Furthermore, other age groups and screen time did not play an important role in three outcome variables.

CONCLUSIONS

The results showed some factors that contribute to three body fat measures. Therefore, it is necessary to develop effective interventions to prevent the effects of individual and environmental undesirable factors on childhood obesity in both family and community levels.

Adherence to healthy diet is related to better linear growth with open growth plate in adolescent girls

Nutritional status can affect the linear growth of bones during puberty by affecting growth plate (GP) chondrocytes. We hypothesized that there is a relationship between dietary patterns and bone age on girls who have experienced height loss. This cross-sectional study was conducted on 350 girls aged 12-13 years with open GP, and major dietary patterns were determined using the factor analysis method. Dual-energy x-ray absorptiometry measurement of participant's wrist was performed to determine GP openness and bone age. In the present study, 70.3% of participants had bone age below chronological age. Three major dietary patterns-healthy, high sugar and salt, and Western diet-were identified using findings of dietary intake. Adherence to the healthy diet led to significant increase in height, weight, body mass index, and other components of body composition such as lean body mass (P < .001). Among these dietary patterns, we found only a significant association between healthy diet and difference between bone and chronological age (B = -0.106). In the present study, adherence to a healthy diet was associated with increase in bone age (P = .02). Healthy dietary pattern with an emphasis on enough intake of plant protein and white meat was associated with better linear growth.

Socioeconomic inequality in cardio-metabolic risk factors in a nationally representative sample of Iranian adolescents using an Oaxaca-Blinder decomposition method: the CASPIAN-III study

Objectives

The present research was conducted aiming at assessing the association of socioeconomic inequality in the prevalence of risk factors associated with cardio-metabolic disorders in a sample population of nationally representative Iranian adolescents and to identify its influencing factors.

Methods

This study was conducted as part of a national-based surveillance program performed on 5625 individuals aged 10-18 years in 27 provinces in Iran. To determine the socioeconomic status (SES) of participants, we defined a new variable by applying the principal component analysis. Doing so, the socioeconomic inequality in cardio-metabolic risk factors was examined over the tertiles of SES using concentration index (C). Then, Oaxaca-Blinder decomposition analysis was carried out in order to decide upon the roots of inequality in the health system.

Results

The mean (standard deviation) age of participants was 14.73 (2.41) years. The prevalence of cardio-metabolic parameters had considerable difference across SES tertiles. Elevated fasting blood glucose (FBG), elevated triglycerides (TG), abdominal obesity, elevated total cholesterol (TC), and metabolic syndrome (MetS) increased linearly by increasing SES tertiles. C index for depressed high density lipoprotein- cholesterol (HDL-C) was negative, which was suggestive of inequality in favor of high SES groups and for other cardio-metabolic parameters, it was positive, which indicate inequality was in favor of the lowest SES groups. The highest gap between the first and third tertiles of socioeconomic was for frequency of abdominal obesity; 13.18% of the lowest SES groups and 20.11% of the highest SES groups had abdominal obesity which accounts 6.93% gap in favor of the highest SES groups. The living area could be named as the main variables standing for the inequality of elevated FBS, elevated LDL-c, low HDL-c and abdominal obesity frequency between the first and the last SES group. In addition, BMI could stand as the main independent variable explaining the gap in elevated TG, elevated TC, elevated BP and MetS prevalence across the lowest and the highest SES group.

Conclusions

The study revealed the considerable inequality in the prevalence of cardio-metabolic risk factors between the highest and the lowest SES groups of Iranian adolescents. Living area and BMI are the two main factors which explained inequality in prevalence of cardio metabolic risk factors between SES groups. These estimations could provide health policy markers with practical information for future complementary analyses.

Stunting and its associated factors among 6-7-year-old children in southern Iran: a nested case-control study

OBJECTIVE

Height-for-age shorter than 3th percentile or 2 sd below the median of the National Center for Health Statistics/WHO growth reference is known as stunting. The present study aimed to measure the association of several factors with stunting in a cohort born from 2009 to 2010 in Shiraz, Iran.Design/Setting/SubjectsNested case-control study conducted on pre-school children in 2016. Participants were 200 children suffering from stunting (case group) and 200 children with normal height (control group).

RESULTS

Results of multivariable logistic regression analysis suggested a significant relationship (adjusted OR; 95 % CI) between stunting and mother's occupation (employed v. housewife: 3·58; 1·73, 7·39) and chronic diseases (yes v. no: 2·93; 1·25, 6·88). In addition, significant associations were found between family income (30 million Rials: 5·63; 2·46, 12·87), diary consumption (very little v. high: 5·93; 1·74, 20·18) and animal protein in diet (low v. very high: 2·42; 1·13, 5·19) and stunting among children. Also, chance of stunting was inversely associated with birth interval (<2 years v. first child: 3·13; 1·45, 6·76) and duration of exclusive breast-feeding (18-24 months v. formula only or breast-feeding for <18 months: 0·53; 0·30, 0·92).

CONCLUSIONS

Mothers being housewife, possibly due to having more time to take care of their children, childhood diseases and consumption of dairy foods are strong and modifiable factors which can positively affect Iranian children's stature. Higher family income is another important factor in stunting but under less parental control.

Prevalence of underweight and wasting in Iranian children aged below 5 years: a systematic review and meta-analysis

PURPOSE

Wasting and underweight are the 2 main indicators of children's undernutrition. We aimed to estimate the prevalence of undernutrition at the national level in Iran.

METHODS

We performed a search for original articles published in international and Iranian databases including MEDLINE, Web of Science, Google Scholar, Scopus, CINHAL (Cumulative Index to Nursing and Allied Health Literature), Scientific Information Database, Irandoc, Iranmedex, and Magiran during January 1989-August 2017. Seven keywords, in English and Persian, including malnutrition, protein energy malnutrition, growth disorders, underweight wasting, weight loss, children below 5 years old, and children, were used to search the databases.

RESULTS

Finally, 17 articles were included in the meta-analysis, based on which the prevalence of underweight and wasting in Iranian children were estimated to be 11% and 5%, respectively. The prevalence rates of underweight among children in the central, western, southern, and northern parts of Iran and at the national level were 24%, 5%, 20%, 17%, and 6%, respectively. The prevalence rates of wasting in the central, western, southern, and northern parts of Iran and at the national level were 9%, 4%, 11%, 5%, and 4%, respectively.

CONCLUSION

Although the prevalence of underweight and wasting in Iran was low, some parts of the country showed high prevalence. The main reason behind this difference in the prevalence of malnutrition may be due to the level of development in different regions.

Socioeconomic inequality in childhood obesity and its determinants: a Blinder-Oaxaca decomposition

OBJECTIVE

Childhood obesity has become a priority health concern worldwide. Socioeconomic status is one of its main determinants. This study aimed to assess the socioeconomic inequality of obesity in children and adolescents at national and provincial levels in Iran.

METHODS

This multicenter cross-sectional study was conducted in 2011-2012, as part of a national school-based surveillance program performed in 40,000 students, aged 6-18-years, from urban and rural areas of 30 provinces of Iran. Using principle component analysis, the socioeconomic status of participants was categorized to quintiles. Socioeconomic status inequality in excess weight was estimated by calculating the prevalence of excess weight (i.e., overweight, generalized obesity, and abdominal obesity) across the socioeconomic status quintiles, the concentration index, and slope index of inequality. The determinants of this inequality were determined by the Oaxaca Blinder decomposition.

RESULTS

Overall, 36,529 students completed the study (response rate: 91.32%); 50.79% of whom were boys and 74.23% were urban inhabitants. The mean (standard deviation) age was 12.14 (3.36) years. The prevalence of overweight, generalized obesity, and abdominal obesity was 11.51%, 8.35%, and 17.87%, respectively. The SII for overweight, obesity and abdominal obesity was -0.1, -0.1 and -0.15, respectively. Concentration index for overweight, generalized obesity, and abdominal obesity was positive, which indicate inequality in favor of low socioeconomic status groups. Area of residence, family history of obesity, and age were the most contributing factors to the inequality of obesity prevalence observed between the highest and lowest socioeconomic status groups.

CONCLUSION

This study provides considerable information on the high prevalence of excess weight in families with higher socioeconomic status at national and provincial levels. These findings can be used for international comparisons and for healthcare policies, improving their programming by considering differences at provincial levels.

Childhood Overweight and Obesity and Associated Factors in Iranian Children and Adolescents: A Multilevel Analysis; the CASPIAN-IV Study

Objective: The purpose of this paper is to explore multidimensional factors related to childhood obesity and overweight based on the data gathered on different aspects of the general health status were assessed among a large number of Iranian children and adolescents in the fourth phase of the "Childhood and Adolescence Surveillance and Prevention of Adult Non-communicable disease" survey. It also aims to determine the degree to which each ecological context contributes to childhood overweight/obesity. Method: A total of 14,880 students and their parents were recruited. They filled out a questionnaire on their relationship with peers, body image, and psychosocial environment of school, dietary habits, life-style habits, physical activity pattern and socioeconomic status (SES). Their height, weight, was measured and body mass index (BMI) was calculated. Obesity and overweight was defined based on the WHO growth chart. Multilevel modeling using three-level random intercept logistic regression models were used to assess predictors of overweight and obesity. In our hierarchical models, children (first level) were conceptualized as being nested within provinces (second level) and provinces within quad regions (third level). Result: From among the 13,486 recruited students, 9.7% were overweight and 11.9% were obese. In multivariate model (adjusted model), being boy (OR:1.58), living in urban area (OR:1.58), having positive family history of obesity (OR = 2.04), breakfast skipping (OR: 1.46), socioeconomic status (OR _{moderateSES/lowSES} = 1.44 and OR _{highSES/lowSES} = 1.89), and birth weight (BW) (OR _{normalBW/lowBW} = 1.33 and OR _highBW/lowBW = 1.8) were associated with childhood obesity. Increasing age was the only factor in the obesity model that had a significant preventive effect on the odds of becoming obese (OR = 0.96, P < 0.001). In multivariate model, living in urban area, increasing age, high and moderate SES, high BW and family history of obesity were the significant predictors of overweight. Conclusion: Our findings show that high BW, sociodemographic characteristics, breakfast skipping, and family history of obesity are associated with childhood obesity and overweight. Therefore, developing strategies that consider the effects of diverse sociodemographic and environmental factors on childhood overweight and obesity would be the most effective way to prevent and manage this multifactorial health concern.

Association between Obesity and Parental Weight Status in Children and Adolescents

OBJECTIVE

This study aims to assess the relationship between body mass index (BMI) of children and that of their parents in a nationally-representative sample of Iranian population.

METHODS

This cross-sectional nationwide study was conducted in 2011-2012 among 6-18-year-old students and their parents living in 30 provinces of Iran. Socio-demographic information was collected. The BMI values of the children/adolescents were categorized according to the World Health Organization reference curves. Association between parental and student weight status was examined using ordinal regression models after adjustment for potential confounders.

RESULTS

Overall, 23043 children and adolescents and one of their parents participated in this study (50.7% boys, 73.4% urban status). Mean age of the subjects was 12.55±3.31 years. Mean BMI values of parents and children/adolescents were 27.0±4.57 and 18.8±4.4 kg/m2, respectively. After adjusting for confounders, overweight and/or obesity in students of both genders was found to be significantly associated with parental overweight and/or obesity. In those students who had obese parents, the odds ratio (OR) of being obese was 2.79 for boys [OR=2.79; 95% confidence interval (CI)=2.44-3.20] and 3.46 for girls (OR=3.46; 95% CI=3.03-3.94) compared to their peers with normal-weight parents. Boys with overweight parents were 1.7 times more overweight than their counterparts with normal-weight parents (OR=1.70; 95% CI=1.15-1.92). Similarly, girls who had overweight parents were more overweight compared to those with normal-weight parents (OR=2.00; 95% CI=1.77-2.25).

CONCLUSION

Our findings highlight the importance of the shared family environment as a multi-factorial contributor to the childhood obesity epidemic and the necessity of implementing family-centered preventive programs.

Prevalence of cardio-metabolic risk factors in a nationally representative sample of Iranian adolescents: The CASPIAN-III Study

Introduction: The aim of the present study is to explore the prevalence and mean of cardiometabolic risk factors and liver enzymes of Iranian adolescents living in regions with different socioeconomic status (SES). To the best of our knowledge this is the first study reporting these data at sub-national level in Iran.

Methods: This multi-centric study was performed in 2009-2010 on a stratified multi-stage probability sample of 5940 students aged 10-18 years, living in urban and rural areas of 27 provinces of Iran. Trained healthcare professionals measured anthropometric indices, systolic and diastolic blood pressures (SBP, DBP) according to standard protocols. Fasting venous blood was examined for fasting blood sugar (FBS), lipid profile and liver enzymes including alanine aminotransferase (ALT) and aspartate aminotransferase (AST). We classified the country into four sub-national regions based on criteria of the combination of geography and SES. Mean and frequency of risk factors were compared across these regions.

Results: The mean of body mass index had linear rise with increase in the regions’ SES (P for trend <0.001). The mean levels of DBP, total cholesterol (TC), high-density lipoproteincholesterol (HDL-C), triglycerides (TG), FBS, ALT, and AST had linear association with regions’ SES in the whole population and in both genders (P for trend < 0.05), whereas the corresponding figure was statistically significant for the mean SBP only in girls (P for trend: 0.03) and for the mean of LDL-C in the whole population and in boys (P for trend <0.001). In total and in both genders, there was an escalating trend in the prevalence of elevated FBS, TC and liver enzymes, low HDL-C, and metabolic syndrome by increase in the SES of the region(P for trend <0.01).

Conclusion: This study proposes that in addition to national health policies on preventing cardiometabolic risk factors, specific interventions should be considered according to the regional SES level.

Association of short stature with life satisfaction and self-rated health in children and adolescents: the CASPIAN-IV study

BACKGROUND

Data on stature in Iranian children and adolescents at national level are limited. The purpose of this study was to investigate the association of short stature with life satisfaction (LS) and self-rated health (SRH) in children and adolescents.

METHODS

Data were obtained from a nationwide survey entitled childhood and adolescence surveillance and prevention of adult non-communicable disease (CASPIAN IV). Participants were 14,880 children and adolescents, aged 6-18 years, who were selected using multistage, cluster sampling method from rural and urban areas of 30 provinces of Iran. LS and SRH were evaluated for every participant by the validated questionnaire prepared based on the global school-based student health survey of the World Health Organization (WHO). Height was measured according to the standard protocol. Short stature was defined as height less than -2 standard deviation (SD) below the mean height for age and sex.

RESULTS

Overall, 13,484 participants with a mean (SD) age of 12.5 (3.36) years (49.24% girls, 50.75% boys) completed the study (response rate 90.6%). The prevalence of short stature, poor SRH and life dissatisfaction was 9%, 20.04% and 20.09%, respectively. Although in the univariate model, participants with short stature had significantly lower odds of LS [odds ratio (OR): 0.83, 95% confidence interval (CI): 0.71-0.97] and good SRH (OR: 0.79, 95% CI: 0.68-0.92), in the multivariate model, only the association of short stature with good SRH remained statistically significant (OR: 0.82, 95% CI: 0.69-0.98).

CONCLUSIONS

Results of the present study show that participants with short stature are at the greater risk of poor SRH and decreased LS in comparison with the subjects with normal height.