Metabolic syndrome and its risk factors among middle aged population of Iran, a population based study

Insulin resistance-related circulating predictive markers in the metabolic syndrome: a systematic review in the Iranian population

Background

Specific biomarkers for metabolic syndrome (MetS) may improve diagnostic specificity for clinical information. One of the main pathophysiological mechanisms of MetS is insulin resistance (IR). This systematic review aimed to summarize IR-related biomarkers that predict MetS and have been investigated in Iranian populations.

Methods

An electronic literature search was done using the PubMed and Scopus databases up to June 2022. The risk of bias was assessed for the selected articles using the instrument suggested by the Joanna Briggs Institute (JBI). This systematic review protocol was registered with PROSPERO (registration number CRD42022372415).

Results

Among the reviewed articles, 46 studies investigated the association between IR biomarkers and MetS in the Iranian population. The selected studies were published between 2009 and 2022, with the majority being conducted on adults and seven on children and adolescents. The adult treatment panel III (ATP III) was the most commonly used criteria to define MetS. At least four studies were conducted for each IR biomarker, with LDL-C being the most frequently evaluated biomarker. Some studies have assessed the diagnostic potency of markers using the area under the curve (AUC) with sensitivity, specificity, and an optimal cut-off value. Among the reported values, lipid ratios and the difference between non-HDL-C and LDL-C levels showed the highest AUCs (≥ 0.80) for predicting MetS.

Conclusions

Considering the findings of the reviewed studies, fasting insulin, HOMA-IR, leptin, HbA1c, and visfatin levels were positively associated with MetS, whereas adiponectin and ghrelin levels were negatively correlated with this syndrome. Among the investigated IR biomarkers, the association between adiponectin levels and components of MetS was well established.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01347-6.

Measurement and Decomposition of Socioeconomic Inequality in Metabolic Syndrome: A Cross-sectional Analysis of the RaNCD Cohort Study in the West of Iran

OBJECTIVES

Socioeconomic inequality in metabolic syndrome (MetS) remains poorly understood in Iran. The present study examined the extent of the socioeconomic inequalities in MetS and quantified the contribution of its determinants to explain the observed inequality, with a focus on middle-aged adults in Iran.

METHODS

This cross-sectional study used data from the Ravansar Non-Communicable Disease cohort study. A sample of 9975 middle-aged adults aged 35-65 years was analyzed. MetS was assessed based on the International Diabetes Federation definition. Principal component analysis was used to construct socioeconomic status (SES). The Wagstaff normalized concentration index (CIn) was employed to measure the magnitude of socioeconomic inequalities in MetS. Decomposition analysis was performed to identify and calculate the contribution of the MetS inequality determinants.

RESULTS

The proportion of MetS in the sample was 41.1%. The CIn of having MetS was 0.043 (95% confidence interval, 0.020 to 0.066), indicating that MetS was more concentrated among individuals with high SES. The main contributors to the observed inequality in MetS were SES (72.0%), residence (rural or urban, 46.9%), and physical activity (31.5%).

CONCLUSIONS

Our findings indicated a pro-poor inequality in MetS among Iranian middle-aged adults. These results highlight the importance of persuading middle-aged adults to be physically active, particularly those in an urban setting. In addition to targeting physically inactive individuals and those with low levels of education, policy interventions aimed at mitigating socioeconomic inequality in MetS should increase the focus on high-SES individuals and the urban population.

Socioeconomic status and metabolic syndrome in Southwest Iran: results from Hoveyzeh Cohort Study (HCS)

BACKGROUND

Socioeconomic status (SES) strongly predicts morbidity and premature mortality, especially for non-communicable diseases (NCDs). However, the effect of these factors on Metabolic Syndrome (MetS) is not clear yet. This study was conducted to assess the relationship between socioeconomic indicators and MetS.

METHODS

In this prospective cohort study, 10,009 people aged 35-70 enrolled from May 2016 to August 2018. The MetS was defined according to The Standard National Cholesterol Education Program (NCEP)-adult treatment panel III (ATP III) or NCEP-ATP III criteria. Demographics and socioeconomic data were gathered face-to-face through trained interviews. Also, lab, anthropometrics, and blood pressure measurements were assayed for participants. Logistic regression was used to estimate the association between SES and MetS, adjusted for the potential confounding factors.

RESULTS

The overall prevalence of MetS in the participants was 39.1%. The crude odds ratios were statistically significant for all the assessed variables (p < 0.05). After adjustment for age, sex, physical activity, smoking, and alcohol use as potential confounders, the results indicated significant direct independent associations between skill level (p = 0.006) and Townsend index (p = 0.002) with MetS. In contrast, no significant associations between educational level and wealth status with MetS.

CONCLUSION

The results of our study showed that SES is related to MetS. Among the four assessed SES indicators, skilled levels and Townsend score are strongly associated with MetS. We recommend considering people's SES when interventional programs are planned and conducted on MetS in similar communities.

Understanding the role of oxidative stress in the incidence of metabolic syndrome and obstructive sleep apnea

BACKGROUND

Understanding the causes and risk factors of metabolic syndrome is important for promoting population health. Oxidative stress has been associated with metabolic syndrome, and also obstructive sleep apnea. These are two diseases which have common prognostic characteristics for heart disease. The aim of this study was to examine the role of oxidative stress in the concurrent presence of metabolic syndrome and obstructive sleep apnea in a working population.

METHODS

Participants were 163 artisan bakers in Shahroud, Iran, routinely exposed to significant heat stress and other oxidative stress indicators on a daily basis as part of their work. Using a cross-sectional design, data relevant to determining metabolic syndrome status according to International Diabetes Federation criteria, and the presence of obstructive sleep apnea according to the STOP-Bang score, was collected. Analyses included hierarchical binary logistic regression to yield predictors of the two diseases.

RESULTS

Hierarchical binary logistic regression showed that oxidative stress - alongside obesity, no regular exercise, and smoking - was an independent predictor of metabolic syndrome, but not obstructive sleep apnea. Participants who were obese were 28 times more likely to have metabolic syndrome (OR 28.59, 95% CI 4.91-63.02) and 44 times more likely to have obstructive sleep apnea (OR 44.48, 95% CI 4.91-403.28). Participants meeting metabolic syndrome criteria had significantly higher levels of malondialdehyde (p <  0.05) than those who did not. No difference in oxidative stress index levels were found according to obstructive sleep apnea status.

CONCLUSIONS

Our findings suggest that oxidative stress contributes to the onset of metabolic syndrome, and that obstructive sleep apnea is involved in oxidative stress. Whilst obesity, exercise, and smoking remain important targets for reducing the incidence of metabolic syndrome and obstructive sleep apnea, policies to control risks of prolonged exposure to oxidative stress are also relevant in occupations where such environmental conditions exist.

A nationwide study of metabolic syndrome prevalence in Iran; a comparative analysis of six definitions

Introduction

To integrate and execute a proper preventive plan and reduce the risk of non-communicable diseases (NCDs), policy makers need to have access to both reliable data and a unique definition of metabolic syndrome (MetS). This study was conducted on the data collected by cross-sectional studies of WHO’s STEPwise approach to surveillance of NCD risk factors (STEPs) to estimate the national and sub-national prevalence rates of MetS in Iran in 2016.

Materials and methods

The prevalence of MetS was estimated among 18,414 individuals aged ≥25 years living in urban and rural areas of Iran using various definition criteria; National Cholesterol Education Program Adult Treatment Panel III 2004 (ATP III), International Diabetes Federation (IDF), American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI), Joint Interim Statement (JIS). Regional IDF (RIDF) and JIS (RJIS) were defined using ethnicity-specific values of waist circumference for the country.

Results

National prevalence rate of MetS based on ATP III, IDF, AHA/NHLBI, JIS, RIDF and RJIS criteria were 38.3% (95% CI 37.4–39.1), 43.5% (42.7–44.4), 40.9% (40.1–41.8), 47.6% (46.8–48.5), 32.0% (31.2–32.9), and 40.8% (40.0–41.7), respectively. The prevalence was higher among females, in urban residents, and those aged 65–69 years. MetS was expected to affect about 18.7, 21.3, 20.0, 23.3, 15.7, and 20.0 million Iranians, respectively, based on ATP III, IDF, AHA/NHLBI, JIS, RIDF and RJIS. The two most common components noted in this population were reduced high-density lipoprotein cholesterol (HDL-C) levels and central obesity.

Conclusion

High prevalence rate of MetS among Iranian adults is alarming, especially among females, urban residents, and the elderly. The JIS definition criteria is more appropriate to determine higher number of Iranians at risk of NCDs. Proper management and prevention of MetS is required to adopt multiple national plans including lifestyle modifications, medical interventions, and public education on NCDs risk factors.

High Prevalence of Metabolic Syndrome and Its Related Demographic Factors in North of Iran: Results from the PERSIAN Guilan Cohort Study

INTRODUCTION

The prevalence of metabolic syndrome has increased in recent decades around the world and is currently reaching epidemic levels as it is a major public health and clinical concern. The aim of this study was to evaluate the prevalence of metabolic syndrome and its related demographic factors in a population-based study.

METHODS

In this cross-sectional study, the target population consisted of 10520 individuals aged 35-70 years in Phase 1 of the Persian Guilan cohort study (Guilan site/Some'e Sara) that was conducted in 2014-2017. Demographic, anthropometric, blood pressure, and biochemical data were used in this study. The IDF definitions were used to diagnose the metabolic syndrome.

RESULTS

The prevalence of the syndrome according to IDF and ATP definition was 42.87% (95% CI: 41.92-41.81) and 40.68% (95% CI: 39.74-41.62), respectively. The prevalence of components for central obesity, high triglyceride, HDL cholesterol, blood glucose, and hypertension components was 75.8%, 43.1%, 40.6%, 39.2% and 37.9%, respectively. All demographic variables were related to the syndrome, and among them age, gender, and residence were identified as independent and strong predictive variables in the regression model. More than 92% of the population had at least one component of the syndrome.

CONCLUSION

The results of the study show a high prevalence of metabolic syndrome risk factors. It is essential to educate healthy lifestyle behaviors and further health education in the high-risk groups identified in this study, especially the elderly, women, and rural residents.

Prevalence and Incidence of Metabolic Syndrome in Iran: A Systematic Review and Meta-Analysis

Metabolic syndrome (MetS) is a predictor of several diseases such as cardiovascular diseases, diabetes, dyslipidemia, stroke, osteoarthritis, certain cancers, and death leading to public health concern in most societies. We aimed to estimate the pooled prevalence and incidence of MetS in Iranian population through a meta-analysis study. We included cross-sectional and cohort studies to estimate the overall prevalence and incidence rates of MetS in Iran National databases including MagIran, Science Information Database, IranMedex, and international databases including Medline, Web of Sciences, and Scopus were searched up to October 2017. Finally, 125 studies were included. The total sample size was 472,401 with a mean age of 38 ± 7.8 years. The overall pooled prevalence and incidence rate among the general population of Iran was 0.26 (95% CI: 0.26, 0.29) and 97.96 (95% CI: 75.98, 131.48), respectively. The pooled prevalence of MetS was higher in females and in urban areas. The highest and lowest prevalence of MetS was obtained by the Iranian definition criteria (0.43) and the NHANES III (0.12). The highest and lowest incidence rates of MetS were obtained by IDF (144.07 per 1000) and the JIS (89.73 per 1000). The prevalence of MetS was higher in women and those living in urban areas. Furthermore, the prevalence of MetS increased with increasing age in both genders.

The prevalence of metabolic syndrome among Iranian bakers

BACKGROUND

Metabolic syndrome (MetS) is a group of risk factors that are associated with increased risk for atherosclerotic cardiovascular disease.

OBJECTIVE

The objective of this study was to determine the prevalence of metabolic syndrome and its individual components among Iranian bakery workers.

METHODS

A cross-sectional study enrolling 163 randomly selected bakery workers from Semnan province (Northeast Iran), was conducted in 2017. A standard questionnaire was used for data collection. Analyses were performed using t-test, one-way ANOVA and Latent Class Analysis (LCA) in R software.

RESULTS

The prevalence of MetS was 19.8% among bakery workers. More bakery workers with MetS had no regular exercise (p = 0.001) and worked more than eight hours a day (p = 0.001). In this study, the International Diabetes Federation (IDF) diagnostic criteria had more agreement with the American Heart Association (AHA) (49.1%) than the World Health Organization (WHO) and Adult Treatment Panel (ATP) criteria. Also, the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATPIII) had the highest sensitivity for diagnosing MetS. The sensitivity of the four diagnostic methods, WHO, IDF, ATP and AHA, were 45.2%, 61.7%, 67.9% and 64.8%; and their specificity were 98.2%, 100%, 100% and 100%, respectively.

CONCLUSION

The prevalence of MetS is high among bakery workers in Iran. Increased physical activity and intake of fruit and vegetables are recommended for the prevention of MetS.

Comparison of the accuracy of three diagnostic criteria and estimating the prevalence of metabolic syndrome: A latent class analysis

Background:

Metabolic syndrome (MetS) is a growing public health problem with a worldwide distribution, and its prevalence is rapidly increasing worldwide. Hence, this study aimed to compare the prevalence of MetS based on the International Diabetes Federation (IDF), the National Cholesterol Education Program Expert Panel Adult Treatment Panel III (NCEP ATP III), and the American Association of Clinical Endocrinologists (AACE) diagnostic criteria.

Materials and Methods:

In this cross-sectional study, a total of 4737 people aged 45–69 years were enrolled in the 2^nd phase of Shahroud Eye Cohort Study. We evaluated the prevalence of MetS with 95% confidence intervals by age and sex groups and according to MetS components. The accuracy (sensitivity and specificity) of these three methods was compared using latent class analysis. Finally, kappa statistic was used to determine the agreement between the diagnostic methods.

Results:

The prevalence of MetS varied from a minimum of 47.2% (as defined by the AACE) to a maximum of 60.0% (as defined by the IDF). The sensitivity of the three diagnostic methods of IDF, NCEP ATP III, and AACE was 98.9%, 94.4%, and 91.1%, respectively, and the specificity of these three methods was 94.6%, 97.0%, and 98.4%, respectively. Moreover, the highest agreement was found between the definition of the IDF and the NCEP ATP III.

Conclusion:

The IDF diagnostic method has a higher sensitivity for the diagnosis of MetS in Iranian middle-aged people. It is recommended to use this method for identifying more people at risk of MetS.

Prevalence of metabolic syndrome in Iran: A meta-analysis

Background

Metabolic syndrome) MetS( is a complex risk factor which increases the risk of cardiovascular diseases and type 2 diabetes. There are many studies with various populations and results about the prevalence of MetS in Iran; in order to authenticate these studies and have an overall estimation of its prevalence in Iran, performing a meta-analysis seems to be necessary.

Objective

This study aimed to investigate the prevalence of MetS and its components in Iran via meta-analysis method.

Methods

All associated published papers in national and international journals of PubMed, Scopus, Web of Science, Magiran, Iranmedex, Science Direct, Medlib, and SID databases were searched from January, 2000 to October, 2016. All types of studies, including local and national surveys that reported the prevalence of MetS among healthy populations in Iran were reviewed. The effects of age, sample size and publication date as possible sources of heterogeneity among the study findings was examined by meta-regression. P-values less than 0.05 were considered as significant in heterogeneity tests. All analysis was done by R Ver. 3.2.1 and STATA (version 10).

Results

Seventy eligible studies were selected for meta-analysis. The overall estimation of MetS prevalence was 25% (95% CI: 22-29%) based on the Adult Treatment Panel III (ATP III) criteria, 30% (95% CI: 25-36%) according to the International Diabetes Federation (IDF), and 39% (95% CI: 26-52%) based on the Joint Interim Societies (JIS) criteria. The prevalence of MetS was lower in men than in women (26.9% versus 35.7%). The prevalence of various MetS components including High TG (triglyceride), Low HDL-C, High BP and High FBS (fasting blood sugar) was 43%, 54%, 38% and 22% among the adult population.

Conclusion

Findings from the present meta-analyses study displayed a high prevalence of metabolic syndrome in Iran, especially in women, which increases with age in both sexes. It alerts health care providers and policy makers to find solutions in order to take action to reduce MetS risk in society.