Factors related to obesity among Iranian men: results from the National Health Survey

Socioeconomic - related inequalities in overweight and obesity: findings from the PERSIAN cohort study

Background

Overweight and obesity are major health concerns worldwide, with adverse health consequences during the life span. This study measured socioeconomic inequality in overweight and obesity among Iranian adults.

Methods

Data were extracted from 129,257 Iranian adults (aged 35 years and older) participated in the Prospective Epidemiologic Research Studies in IrAN (PERSIAN) in 14 provinces of Iran in 2014. Socioeconomic-related inequality in overweight and obesity was estimated using the Concentration Index (C_n). The C_n further decomposed to find factors explaining the variability within the Socioeconomic related inequality in overweight and obesity.

Results

Of the total number of participants, 1.98, 26.82, 40.76 and 30.43% had underweight, normal weight, overweight and obesity respectively. The age-and sex standardized prevalence of obesity was higher in females than males (39.85% vs 18.79%). People with high socioeconomic status (SES) had a 39 and 15% higher chance of being overweight and obese than low SES people, respectively. The positive value of C_n suggested a higher concentration of overweight (0.081, 95% confidence interval [CI]; 0.074–0.087) and obesity (0.027, 95% CI; 0.021–0.034) among groups with high SES. There was a wide variation in socioeconomic-related inequality in overweight and obesity rate across 14 provinces. The decomposition results suggested that SES factor itself explained 66.77 and 89.07% of the observed socioeconomic inequalities in overweight and obesity among Iranian adults respectively. Following SES, province of residence, physical activity, using hookah and smoking were the major contributors to the concentration of overweight and obesity among the rich.

Conclusions

Overall, we found that overweight and obesity is concentrated among high SES people in the study population. . Accordingly, it seems that intersectional actions should be taken to control and prevent overweight and obesity among higher socioeconomic groups.

Application of the Marginal Beta-Binomial Model in Estimation the Overall Odds of Obesity Among Iranian Adults: Meta-Analysis Method

CONTEXT

To obtain accurate and reliable estimation of overall obesity odds ratio (OR) a statistical method is needed to be designed to account for heterogeneity among studies. The marginal beta-binomial model is a new method with attractive features that make it robust for meta-analysis.

OBJECTIVES

The aim of this study is the estimation of overall obesity OR among Iranian adults with particularly attention to age, sex, place of residence, and smoking status.

DATA SOURCES

We systematically reviewed all studies regarding obesity in Iranian adults in national and international journals that are published between 1990 and 2017, including PubMed, Scopus, SID, Google Scholar, Magiran, and IranMedex. The R software was used for data analysis and obtaining overall obesity OR using the marginal beta-binomial model.

RESULTS

A total of 18 studies, with a sample size of 258283, were included in our analysis. Results showed that increasing age, female sex, and residence in urban areas increases the odds of obesity. Using the age group 20 - 30 years as the reference, the overall obesity ORs for 30 - 40, 40 - 50, 50 - 60, and 60+ years were 2.13, 3.33, 3.15, and 2.33, respectively. The overall obesity OR for women was 2.35, compared with men. The estimated odds of obesity were 53% higher for urban adults. Smoking has a negative effect on obesity; the OR of obesity for smokers was 0.48 compared with non-smokers.

CONCLUSION

Consistent results in our research can be used as a basis to reinforce health programs for prevention and treatment of obesity in Iran.

Obesity and its socioeconomic determinants in Iran

OBJECTIVE

To investigate the socioeconomic inequality of obesity and its determinants in Iran.

METHODS

Data was from Iran's surveillance system for risk factors of non-communicable diseases which was conducted on 89,400 individuals aged 15-64 years in 2005. Principal component analysis was used to create a new variable for defining socioeconomic status of participants. We assessed inequality by calculating a slop index of inequality and concentration index for obesity. Oaxaca-Blinder decomposition analysis was used to determine the determinants of inequality.

RESULTS

The slop index of inequality and concentration index for obesity was -13.1 (95% Confidence Intervals [CI]: -16.3 to -9.8) percentage points and -0.123, respectively. The level of inequality varied widely between different provinces in Iran and was more severe in women and urban population. Obesity persisted in 20.2% (95% CI: 19.4-20.9) of the low-socioeconomic group and 11.0% (95% CI: 10.5-11.6) of the high-socioeconomic group. More than 90% of this gap was due to differences of independent variables (mainly age, gender and marital status) in two socioeconomic status groups.

CONCLUSIONS

A pro-rich inequality existed in the obesity in Iran. Older age, female gender and rural residency contributed most to the economic inequality of obesity.

Changes in Obesity Odds Ratio among Iranian Adults, since 2000: Quadratic Inference Functions Method

Background. Monitoring changes in obesity prevalence by risk factors is relevant to public health programs that focus on reducing or preventing obesity. The purpose of this paper was to study trends in obesity odds ratios (ORs) for individuals aged 20 years and older in Iran by using a new statistical methodology. Methods. Data collected by the National Surveys in Iran, from 2000 through 2011. Since responses of the member of each cluster are correlated, the quadratic inference functions (QIF) method was used to model the relationship between the odds of obesity and risk factors. Results. During the study period, the prevalence rate of obesity increased from 12% to 22%. By using QIF method and a model selection criterion for performing stepwise regression analysis, we found that while obesity prevalence generally increased in both sexes, all ages, all employment, residence, and smoking levels, it seems to have changes in obesity ORs since 2000. Conclusions. Because obesity is one of the main risk factors for many diseases, awareness of the differences by factors allows development of targets for prevention and early intervention.

Assessing factors related to waist circumference and obesity: application of a latent variable model

Background. Because the use of BMI (Body Mass Index) alone as a measure of adiposity has been criticized, in the present study our aim was to fit a latent variable model to simultaneously examine the factors that affect waist circumference (continuous outcome) and obesity (binary outcome) among Iranian adults. Methods. Data included 18,990 Iranian individuals aged 20–65 years that are derived from the third National Survey of Noncommunicable Diseases Risk Factors in Iran. Using latent variable model, we estimated the relation of two correlated responses (waist circumference and obesity) with independent variables including age, gender, PR (Place of Residence), PA (physical activity), smoking status, SBP (Systolic Blood Pressure), DBP (Diastolic Blood Pressure), CHOL (cholesterol), FBG (Fasting Blood Glucose), diabetes, and FHD (family history of diabetes). Results. All variables were related to both obesity and waist circumference (WC). Older age, female sex, being an urban resident, physical inactivity, nonsmoking, hypertension, hypercholesterolemia, hyperglycemia, diabetes, and having family history of diabetes were significant risk factors that increased WC and obesity. Conclusions. Findings from this study of Iranian adult settings offer more insights into factors associated with high WC and high prevalence of obesity in this population.

How Accurate Are the Anthropometry Equations in in Iranian Military Men in Predicting Body Composition?

BACKGROUND

The body composition varies according to different life styles (i.e. intake calories and caloric expenditure). Therefore, it is wise to record military personnel's body composition periodically and encourage those who abide to the regulations. Different methods have been introduced for body composition assessment: invasive and non-invasive. Amongst them, the Jackson and Pollock equation is most popular.

OBJECTIVES

The recommended anthropometric prediction equations for assessing men's body composition were compared with dual-energy X-ray absorptiometry (DEXA) gold standard to develop a modified equation to assess body composition and obesity quantitatively among Iranian military men.

PATIENTS AND METHODS

A total of 101 military men aged 23 - 52 years old with a mean age of 35.5 years were recruited and evaluated in the present study (average height, 173.9 cm and weight, 81.5 kg). The body-fat percentages of subjects were assessed both with anthropometric assessment and DEXA scan. The data obtained from these two methods were then compared using multiple regression analysis.

RESULTS

The mean and standard deviation of body fat percentage of the DEXA assessment was 21.2 ± 4.3 and body fat percentage obtained from three Jackson and Pollock 3-, 4- and 7-site equations were 21.1 ± 5.8, 22.2 ± 6.0 and 20.9 ± 5.7, respectively. There was a strong correlation between these three equations and DEXA (R² = 0.98).

CONCLUSIONS

The mean percentage of body fat obtained from the three equations of Jackson and Pollock was very close to that of body fat obtained from DEXA; however, we suggest using a modified Jackson-Pollock 3-site equation for volunteer military men because the 3-site equation analysis method is simpler and faster than other methods.

Obesity and Related Factors in Iran: The STEPS Survey, 2011

Background:

To date, no study has addressed the association between race/ethnicity and obesity considering other sociodemographic and lifestyle factors in Iran.

Objectives:

The current study aimed to study lifestyle and the environmental factors affecting obesity in the Iranian subjects of the STEPS Survey, 2011.

Patients and Methods:

The study was conducted on 8639 subjects (aged ≥ 20 years) in the STEPS Survey 2011 in Iran under supervision of the World Health Organization (WHO). Height and body weight were measured following the standardized procedures. Generalized Estimating Equations (GEE) method was used to examine factors associated with obesity. The examined variables were age, gender, race/ethnicity, place of residence, employment status, physical activity, smoking status, and educational level.

Results:

Overall, 22.3% of the subjects were obese. In a GEE model, a healthy weight status among adults was associated with being younger, male, in a rural residence, employees, spending more time engaged in physical activity, being a smoker and having a moderate or high level of education. These associations were statistically significant after adjusting for other variables.

Conclusions:

The study results suggest a need for targeted interventions and continued surveillance for the Iranian adults.

Educational attainment and obesity: a systematic review

Although previous systematic reviews considered the relationship between socioeconomic status and obesity, almost 200 peer-reviewed articles have been published since the last review on that topic, and this paper focuses specifically on education, which has different implications. The authors systematically review the peer-reviewed literature from around the world considering the association between educational attainment and obesity. Databases from public health and medicine, education, psychology, economics, and other social sciences were searched, and articles published in English, French, Portuguese and Spanish were included. This paper includes 289 articles that report on 410 populations in 91 countries. The relationship between educational attainment and obesity was modified by both gender and the country's economic development level: an inverse association was more common in studies of higher-income countries and a positive association was more common in lower-income countries, with stronger social patterning among women. Relatively few studies reported on lower-income countries, controlled for a comprehensive set of potential confounding variables and/or attempted to assess causality through the use of quasi-experimental designs. Future research should address these gaps to understand if the relationship between educational attainment and obesity may be causal, thus supporting education policy as a tool for obesity prevention.

Factors associated with obesity in Iranian elderly people: results from the national health survey

Background

No studies have been carried out so far to cover the association between factors related to obesity, in a representative sample of the Iranian elderly population.

Methods

The data in this investigation were taken from the National Health Survey in Iran, which included 4380 people aged 60 and older. The logistic regression was applied to model the relationship between the odds of obesity and age, sex, education level, place of residence, smoking and marital status.

Results

Obesity odds ratios were 1.96 (95% CI: 1.53--2.52) for women, 2.16 (95% CI: 1.71--2.72) for the subjects living in urban areas and 0.68 (95% CI: 0.47--0.97) for smokers. Regarding the people aged 60-64 years as the reference group, the obesity odds ratios were 0.86 (95% CI: 0.66--1.10) for ages 65-69 years, 0.75 (95% CI: 0.57--0.97) for ages 70-74 years, 0.43 (95% CI: 0.30--0.60) for ages 75-79 years and 0.36 (95% CI: 0.20--0.63) for ages 80+ years. Using the basic education level as the reference group, obesity odds ratios were 1.38 (95% CI: 1.08-1.76) for the moderate level and 0.92 (95% CI: 0.56- 1.52) for the high level group.

Conclusions

As the result of findings, we are optimistic that we would be able to contribute to the aged community of the society, which could be achieved by means of better treatments and reductions in the rate of obesity.