Classification and Diagnostic Prediction of Colorectal Cancer Mortality Based on Machine Learning Algorithms: A Multicenter National Study.

INTRODUCTION: Colorectal cancer (CRC) ranks as the second leading cause of cancer-related deaths. This study aimed to predict survival outcomes of CRC patients using machine learning (ML) methods. MATERIAL AND METHODS: A retrospective analysis included 1853 CRC patients admitted to three prominent tertiary hospitals in Iran from October 2006 to July 2019. Six ML methods, namely logistic regression (LR), Naïve Bayes (NB), Support Vector Machine (SVM), Neural Network (NN), Decision Tree (DT), and Light Gradient Boosting Machine (LGBM), were developed with 10-fold cross-validation. Feature selection employed the Random Forest method based on mean decrease GINI criteria. Model performance was assessed using Area Under the Curve (AUC). RESULTS: Time from diagnosis, age, tumor size, metastatic status, lymph node involvement, and treatment type emerged as crucial predictors of survival based on mean decrease GINI. The NB (AUC = 0.70, 95% Confidence Interval [CI] 0.65-0.75) and LGBM (AUC = 0.70, 95% CI 0.65-0.75) models achieved the highest predictive AUC values for CRC patient survival. CONCLUSIONS: This study highlights the significance of variables including time from diagnosis, age, tumor size, metastatic status, lymph node involvement, and treatment type in predicting CRC survival. The NB model exhibited optimal efficacy in mortality prediction, maintaining a balanced sensitivity and specificity. Policy recommendations encompass early diagnosis and treatment initiation for CRC patients, improved data collection through digital health records and standardized protocols, support for predictive analytics integration in clinical decisions, and the inclusion of identified prognostic variables in treatment guidelines to enhance patient outcomes.

Population attributable risk fraction of modifiable risk factors associated with poor self-rated health among children and adolescent; the CASPIAN-V study.

BACKGROUND: We aimed to determine the population attributable risk fraction (PARF) of the risk factors for poor SRH in Iranian children and adolescents. METHOD: This was a nationwide cross-sectional study conducted in 2015 among 14,400 students aged 6-18 years, living in 30 provinces of Iran. Data were collected using global school health survey questionnaire. Logistic regression was employed to determine the adjusted association of modifiable risk factors with SRH. We used average PARF to determine the preventable proportion of poor reported SRH. RESULTS: Of 14,400 recruited students, data on 13,983 subjects were analyzed in current study. The mean (SD) age of participants (n = 13,983) was 12.3 (3.16) years, and 49.3% were female. Poor SRH was reported in 19% of subjects. In total, 77% of poor reported SRH in Iranian children and adolescents could be attributed to insufficient daily sleep duration, physical injury, lack of close friend, dissatisfaction with family relationship, and the lack of a companion to share personal problems. We also found that physical pain had the largest PARF (32.4%) followed by anxiety (26.1%) and un-satisfaction with family relationship (5.2%). CONCLUSION: The established physical and social support factors of poor SRH were associated with a remarkable proportion of poor SRH in the Iranian pediatric population. Changing the children's risk factor profile to the lowest physical risk factor as well as reducing the anxiety level and preventing from physical painsmay significantly improve the SRH of children and adolescents.

Perceived job demands: a qualitative study of workplace stress in the Iranian healthcare workers (HCWs).

OBJECTIVES: Work-related stress is a common risk factor among healthcare workers (HCWs). In Iran, the healthcare system has undergone extensive changes to develop services. Organisational change has led to the creation of new working conditions for HCWs. The purpose of this study is to identify job demands that health workers perceive as stressors. DESIGN: As a qualitative study, semistructured interviews, a focus group, and related data were analysed both inductively and deductively with reference to the job demand component based on the job demands-resources model and MAXQDA. SETTING: This investigation was conducted in 18 primary healthcare centres in Qazvin, Iran. PARTICIPANT: Twenty-one female HCWs with at least 6 months of work experience and an average age of 34.4 years. RESULTS: The participants identified six key elements as the stressful job demands including organisation's supervisory function, role characteristics, workload, job insecurity, client service challenges and perceived job content. CONCLUSIONS: After organisational changes and development, HCWs were faced with role changes and increased workload. In addition, organisational supervision in terms of quantity and quality and lack of job security intensified the pressures. These factors led to the high level of stress among employees who dealt with people and those who perceived their job content as unfavourable. Perhaps teaching stress control skills and organisational support interventions can be useful to reduce and control stress among HCWs.

Socioeconomic difference in physical activity in children and their parents: The childhood and adolescence surveillance and prevention of adult noncommunicable disease study.

Background: As a health-related behavior, physical activity (PA) differs according to individual's socioeconomic status (SES). This study aimed to assess the socioeconomic difference in leisure-time PA among Iranian students and their parents at national and regional levels. Study Design: Nationwide cross-sectional study. Methods: This study was conducted as part of a national survey conducted in 2015 among 14400 Iranian students and their parents. Total PA level was measured as the average hours spent on PA per week. Nonlinear principal component analysis was used to construct the households' SES based on household's assets, type of house ownership, occupation of fathers and the educational levels of fathers and mothers. Concentration index was applied to measure the inequality in the PA level in parents and students. Results: Complete data of 13313 students and their parents were available. At the national level, students spent more hours of PA per week (3.753 h per week [h/w]) as compared to their parents. Moreover, PA h/w was higher in fathers (3.488 h/w) as compared to mothers (2.763 h/w). The lowest means of mother's and student's PA were found in the highest SES region. At national level, the concentration indices (CI) of father's and mother's PA were -0.050 (95% CI = -0.067 ~ -0.030) and -0.028 (95% CI = -0.044 ~ -0.012), respectively, indicating pro-poor inequality, but the CI value of student PA was non-significant (CI = -0.007, 95% CI = -0.023-0.008). Conclusions: Given that the mother's and student's PA level was low in the high SES regions, it is suggested that focused PA planning may further increase the level of PA across higher SES regions and might be effective in reducing the PA inequality.

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.

A Nationwide Study on the Seroprevalence of Measles, Mumps, and Rubella in Iranian Children and Adolescents.

Background: Assessing the prevalence of infections, which are preventable by vaccination, is crucial to monitor the vaccination program efficacy, and it can demonstrate the gaps in population immunity. The current study attempted to assess the specific Immunoglobulin (IgG) antibody against measles, mumps, and rubella (MMR) in Iranian children and adolescents, years after their vaccination. Methods: This cross-sectional study was conducted in Iran. Serum samples of 2100 students, aged 7-18 years, included in a national health survey, were tested for MMR antibodies by ELISA assay. Multistage random cluster sampling was used to select subjects from 30 provinces in Iran. Results: Overall, 1871, 1718, and 1678 serums were tested for measles, mumps, and rubella antibodies, respectively. The prevalence of positive test was 1231 (65.8%) for measles, 1327 (77.2%) for mumps and 1344 (80.1%) for rubella. Conclusion: Despite high vaccination coverage in Iran, IgG antibody against measles, mumps, and rubella was not detected in a considerable proportion of children and adolescents aged 7-18 years. In case of contacts with residents of other countries, where measles or rubella have not yet been eliminated, it may create problems for Iranian children.

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 short stature and obesity with cardio-metabolic risk factors in Iranian children and adolescents: the CASPIAN-V study.

PURPOSE: The object of the present study was to examine the relationship of short stature and obesity with cardio-metabolic risk factors in children and adolescents from Iran. METHODS: Present nationwide cross-sectional study was conducted as a part of the fifth survey of CASPIAN study on 7 to 18 years old children and adolescents from 30 provinces of Iran in 2015. Short stature and excess weight were defined as age and sex-specific height lower than 5th percentile and BMI higher than 85th percentile respectively. The multivariate logistic regression model was applied to assess the aim of the study. RESULTS: A total of 3844 children and adolescents (52.4%: boys, 72.2%: urban areas) with an average age of 12.45 ± 3.04 years were enrolled in this study. The prevalence of short stature, excess weight and combined-short stature and excess weight was estimated as 15.8%, 17.6% and 2.2%. Odds of abdominal obesity in children with only short stature (OR: 2.11, 95%CI: 1.59-2.80), only excess weight (OR: 17.38, 95%CI: 13.89-21.75) and combined-short stature and excess weight (OR: 22.83, 95%CI: 13.93-37.39) were higher than children with normal-height and weight. Moreover, odds of high BP and metabolic syndrome were further in the students with combined excess weight and short stature compared to the normal-height and weight group. CONCLUSION: We found that abdominal obesity, hypertension, and metabolic syndrome in short stature and obese children and adolescents were greater than those with normal-height and weight. Further prospective evaluations are required to clarify the association between short stature and cardio-metabolic risk factors.

Erratum: Author Correction: Association of a body shape index and hip index with cardiometabolic risk factors in children and adolescents: the CASPIAN-V study.

[This corrects the article DOI: 10.1007/s40200-021-00743-0.].

Social inequalities in meal skipping patterns among children and adolescents: The CASPIAN-V study.

BACKGROUND & AIM: The appropriate meal consumption affects the children's and adolescents' health. Few studies have shown an association between the socioeconomic inequality and the eating behavior among children and adolescents. Therefore, the aim of this study was to assess the socioeconomic inequality in meal skipping patterns among children and adolescents. MATERIALS & METHODS: The data were accessible through the fifth round of a school-based program in Iran in 2015. In this cross-sectional nationwide study, 14,286 students aged 7-18 years were selected via the multistage cluster sampling from 30 provinces of Iran. The Global School-based Health Survey validated questionnaire was used to assess the socioeconomic variables and meal consumption patterns among children and adolescents. Socioeconomic status (SES) was computed using principle component analysis method. Multivariate logistic regression analysis was used to assess the socioeconomic inequality in meal skipping patterns. RESULTS: The frequency of breakfast, lunch, and dinner skipping were 13.8% (95% CI: 13.3-14.5), 6.8% (95% CI: 6.4-7.2), and 7.5% (95% CI: 7.1-7.9), respectively. In multivariate model, living in a two-parent family compared to living in a single-parent family decreased the odds of breakfast skipping (OR: 0.53, 95% CI: 0.42-0.67)). Low SES level was associated with higher odds of skipping breakfast (OR: 1.79, 95% CI: 1.50-2.14) and dinner (OR: 1.80, 95% CI: 1.42-2.28). Moreover, maternal illiteracy and unemployment were associated with skipping breakfast, lunch, and dinner (all p values < 0.05). CONCLUSION: Some demographic and socioeconomic characteristics, such as maternal illiteracy and unemployment, low SES level, and living in a single-parent family were suggested as the main predictors of meal skipping patterns in children and adolescents.

Worldwide disaster loss and damage databases: A systematic review.

Nowadays, disaster databases have become a valuable tool for disaster risk management and health promotion and serve various purposes. The purpose of this study is to provide a systematic review of disaster databases in the world and to identify the objectives, information sources, criteria, and variables of disaster data registration in the world's reputable databases. To conduct review, all English-language articles published without a time limit until the end of September 2020 were extracted from the databases of Web of Science, PubMed, Scopus, Cochrane Library, Science Direct, Google Scholar, and Embase. Necessary information in the papers including study time, type of disasters, related databases, dimensions and indicators of global and regional databases were extracted by using a researcher-made questionnaire. A total of 22 studies have been reviewed to identify the dimensions and indicators of disaster databases worldwide. The main focus was on global and regional databases, mostly used at the level of scientific societies and disaster experts. After explanation, researchers highlighted each of the disaster databases, along with the main differences available among the existing databases. Some databases have well-defined data collection methods. Their knowledge is high quality and they can be used to create and improve a disaster database at other levels. Disaster database limitations include risk bias, time bias, accounting bias, threshold bias, and geographical bias. To support the right decisions to reduce disaster risk, it is necessary to complement existing global, regional, and national databases. Countries need to take action to set up national databases.

Association of vitamin D status and cardio-metabolic risk factors in children and adolescents: the CASPIAN-V study.

BACKGROUND: Metabolic syndrome (MetS) starts from early life and is one of the important underlying factors for non-communicable diseases (NCDs) in adulthood. Controversial evidence exists on the role of vitamin D deficiency in increasing the risk of pediatric MetS. OBJECTIVE: This study aimed to assess the relationship between vitamin D level with MetS and its components in children and adolescents. METHODS: This nationwide cross-sectional study was performed as part of a surveillance program in Iran. Participants were 2596 students, aged 7 to 18 years, living in 30 provinces. In addition to filling questionnaires, a physical examination was conducted, and blood samples were collected. The serum concentration of 25-hydroxy vitamin D (25(OH)D) was measured using the direct competitive immunoassay chemiluminescence method. RESULTS: 2596 students with a mean age of 12.2 y (55.1% boys) were recruited. Prevalence of vitamin D deficiency and insufficiency in participants was 10.6% (n = 276), and 60.5% (n = 1570), respectively. The prevalence of MetS was higher in the vitamin D deficient group. Students with deficient vitamin D levels had higher odds of MetS (OR: 4.25, 95%CI: 2.26-7.98), abdominal obesity (OR: 2.24, 95%CI: 1.61-3.12), low HDL-C (OR: 1.65, 95%CI: 1.18-2.30) and high fasting blood sugar (OR: 2.56, 95%CI: 1.43-4.57) in comparison to those with sufficient level of vitamin D. CONCLUSION: Vitamin D deficiency was associated with increased odds of MetS and its components in the Iranian pediatric population. These findings underscore the importance of prevention and control of vitamin D deficiency in preventative programs against NCDs.

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.

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.

Association of a body shape index and hip index with cardiometabolic risk factors in children and adolescents: the CASPIAN-V study.

OBJECTIVE: This study designed to discover the link between a body shape index (ABSI) and hip index (HI) with cardiometabolic risk factors (CMRFs) in Iranian children and adolescents. SUBJECTS AND METHODS: In a nationwide cross-sectional survey, 4200 students who were 7-18 years old were chosen via a multistage cluster sampling method in 30 provinces of Iran in 2015. Metabolic syndrome (MetS) was defined in line with the Adult Treatment Panel III criteria. ABSI and HI were defined as waist circumference (m)/ [body mass index 2/3 * height (m)1/2] and hip circumference (cm) *(height/ 166 cm)0.310 *(weight / 73 kg)-0.482 respectively. Association between ABSI and HI with CMRFs as categorical and continuous variables were evaluated using multivariable logistic and linear regression analysis respectively. RESULTS: Totally, information of 14,002 students and findings of blood samples of 3483 of them were involved in the current study. In the multivariable logistic regression, an association of HI with high triglyceride (TG) (OR: 0.99, 95 % CI: 0.98-0.99) and ABSI with MetS (OR: 11.41, 2.61-49.88) was statistically significant (P < 0.05). Also, both indices were significantly associated with overweight, generalized, and abdominal obesity. In the multivariable linear regression analysis, increasing HI (per one unit) was associated with body mass index z-score (z-BMI) (ß: -0.01), waist circumference (WC) (ß: 0.15), TG (ß: -0.16), and systolic blood pressure (SBP) (ß: -0.02). Moreover, in the multivariable linear models, ABSI was significantly associated with z-BMI, WC, SBP, and diastolic blood pressure (P < 0.001). CONCLUSIONS: ABSI and HI as novel body shape indices were significantly associated with some CMRFs. Therefore, these indices can be used as some useful anthropometric risk indices for predicting MetS.

Prevalence and determinants of vitamin D deficiency in Iranian children and adolescents: the CASPIAN-V study.

PURPOSE: To examine the prevalence and determinants of vitamin D deficiency in Iranian children and adolescents. METHODS: We used data from a national school-based surveillance program conducted among 7-18-year-old children and adolescents living in rural and urban areas in 30 provinces of Iran. Data on student's lifestyle, health behaviors, and health status was obtained through a validated questionnaire. Serum 25-hydroxy vitamin D (25-OH-D) level was measured by chemiluminescent immunoassay. Vitamin D deficiency was defined as serum 25-OH-D concentrations < 30 ng/ml. Determinants of vitamin D deficiency were identified using logistic regression analysis. RESULTS: Data of 2,596 participants were available for this study. Prevalence of vitamin D deficiency was 71.1 % (95 % Confidence interval (CI): 69.3-72.8 %), without significant difference between boys and girls (72.0 % vs. 70.1 %, respectively, p = 0.29). In the multivariate regression model, in both genders, those who reported having sun exposure for at least 30 min/day and those taking vitamin D supplementation had lower odds for vitamin D deficiency (all p values < 0.05). In boys, obesity increased the odds of vitamin D deficiency (adjusted OR, 95 % CI: 1.57, 1.08-2.27). The association of vitamin D deficiency with other demographic characteristics and food items was not statistically significant. CONCLUSIONS: This large population-based study revealed a high frequency of hypovitaminosis D in Iranian children and adolescents. Sun exposure for at least 30 min/day and taking vitamin D supplementation may reduce the risk of vitamin D deficiency.

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.

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.