Validity and Reliability of the Iranian Version of the Short Form Social Well Being Scale in a General Urban Population

Background: We aimed to investigate the reliability and validity of the Iranian version of the short form social well-being scale. Methods: After linguistic validation, the Iranian version of social well-being scale was completed by 715 participants, aged ≥18 yr between Jan and Sep 2015. Concurrent validity was examined by calculating the Pearson’s correlation coefficient between the dimensions of social well-being and social support. Internal consistency, Cronbach’s alpha coefficient, confirmatory and explanatory factor analyses were also examined. Results: The internal consistency as measured by Cronbach’s alpha coefficients was 0.72 for total score. No ceiling and floor effect was found in total score or any of the subscales. The concurrent correlation coefficients between social well-being and social support ranged from good to excellent agreement. Exploratory factor analysis supported mainly comparable results with the original US English dialect version. The results of the confirmatory factor analysis for 5-factor models indicated acceptable fit for the proposed research models. Conclusion: The findings support the initial reliability and validity of the Iranian version of the social well-being scale in the research and community settings in Iran.

Trends of Obesity in 10-Years of Follow-up among Tehranian Children and Adolescents: Tehran Lipid and Glucose Study (TLGS)

BACKGROUND

We aimed to investigate the trend of childhood obesity in Tehranian population during a median follow-up of 10 years.

METHODS

Within a prospective cohort study, using data collected from Tehran Lipid and Glucose Study (TLGS), 1406 participants, aged 3-11 yr were selected and monitored in 4 phases: phase I (1999-2001), phase II (2002-2005), phase III (2006-2008) and phase IV (2009-2011).

RESULTS

Total prevalence of obesity in children increased from 5.5% to 9.4% from phase I to IV. Performing GEE (Generalized Estimating Equation) analysis, relative risk of obesity was calculated, comparing each phase to its previous phase: phase II in reference to phase I (RR=1.06, CI=1.04-1.08), phase III in reference to phase II (RR=1.01, CI=1.00-1.03) and phase IV in reference to phase III (RR=0.96, CI=0.94-0.98). Between group difference was significant in all subgroups (age, gender, parental obesity) except parental education. Test of interaction for effect of time was insignificant in all subgroups except for the age group. For children younger than 7 yr old at phase I, trend of obesity throughout the study was higher compared to those with 7 yr of age and older at phase I.

CONCLUSION

During a decade of follow-up, trend of obesity was rising in this Tehranian children in both genders, especially in younger children. Any preventive interventions for stopping this trend should focus on early stages of childhood.

Seasonal Variations of Serum Zinc Concentration in Adult Population: Tehran Lipid and Glucose Study

BACKGROUND

Zinc, an essential trace element, plays a key role in many biological human body functions. Serum zinc concentration is the most widely used indicator of zinc status for general populations. Considering the limited data available on seasonal fluctuation of serum zinc concentration, we aimed at determining seasonal variations in serum zinc concentrations of Tehranian adults.

METHODS

The current study was conducted within the framework of the Tehran Lipid and Glucose Study, on 4698 subjects, aged ≥20 years. Serum zinc samples of subjects were obtained from all four seasons over three years (from 2009 to 2011); samples of similar seasons over three years were placed in one group and the geometric means of serum zinc concentration of four seasons were compared to determine possible seasonal variations.

RESULTS

Participants with mean age 46.3 yr and geometric mean of serum zinc concentration 116.3 μg/dl, were studied for almost three years through four seasons. Serum zinc concentrations in spring and summer were significantly higher than those in autumn and winter (112.2 and 114.4 vs. 106.7 and 104.8 μg/dl; P<0.001, respectively). Moreover, monthly serum zinc concentration of all subjects differed, with the lowest and highest levels found in October and August (98.5 vs. 122.7; P<0.001).

CONCLUSION

This study demonstrates the difference in serum zinc concentration in Iranian adults of both genders in different months and seasons during the year.

Validity and Reliability of the Iranian Version of the Short Form Social Well Being Scale in a General Urban Population

BACKGROUND

We aimed to investigate the reliability and validity of the Iranian version of the short form social well-being scale.

METHODS

After linguistic validation, the Iranian version of social well-being scale was completed by 715 participants, aged ≥18 yr between Jan and Sep 2015. Concurrent validity was examined by calculating the Pearson's correlation coefficient between the dimensions of social well-being and social support. Internal consistency, Cronbach's alpha coefficient, confirmatory and explanatory factor analyses were also examined.

RESULTS

The internal consistency as measured by Cronbach's alpha coefficients was 0.72 for total score. No ceiling and floor effect was found in total score or any of the subscales. The concurrent correlation coefficients between social well-being and social support ranged from good to excellent agreement. Exploratory factor analysis supported mainly comparable results with the original US English dialect version. The results of the confirmatory factor analysis for 5-factor models indicated acceptable fit for the proposed research models.

CONCLUSION

The findings support the initial reliability and validity of the Iranian version of the social well-being scale in the research and community settings in Iran.

Serum Concentration of Thyroid Hormones Long-Term after Sulfur Mustard Exposure

BACKGROUND

Despite several reports on the clinical manifestations of sulfur mustard (SM) intoxication, there is no study on serum concentrations of thyroid hormones long-term after SM exposure. In this study, the changes in thyroid functioning parameters 20 yr after SM exposure were evaluated.

METHODS

This study is a part of a larger historical cohort study conducted in 2007 following 20 years of the exposure to SM, called Sardasht-Iran cohort study (SICS). We (SICS) comprised an SM-exposed group from Sardasht City, West Azerbaijan Province, Iran (n=169 as hospitalized group and n=203 as non-hospitalized exposed group); and control participants were selected from Rabat, a town near Sardasht (n=126). Peripheral blood samples were taken in fasting state and then the sera were separated. T4, T3, TSH, antithyroglobulin (anti-Tg), and antithyroid peroxidase (anti-TPO) concentrations in the sera were measured by the ELISA method.

RESULTS

The mean of T3 concentration was significantly higher in the exposed than control group (0.88 ± 0.26 nmol/L vs 0.8 ± 0.25 nmol/L, P<0.001). The levels of TSH, T4, and T3up were not significantly different between the exposed and control groups. Thyroglobulin level was significantly higher in the exposed non-hospitalized group (56.07 ± 140.22 μg/L vs 17.66 ± 41.49 μg/L, P=0.004), but the level of anti-Tg and anti-TPO showed no significant differences between the two groups.

CONCLUSION

More studies are needed on the alterations in thyroid hormones, their gene expressions, and mechanisms involved in SM exposure to clarify the causes of these alterations.

Estimation and Validation of Dietary Nitrate and Nitrite Intake in Iranian Population

BACKGROUND

The aim of this study was calibration of a nitrate (NO₃)/nitrite (NO₂) database for estimated its dietary intakes.

METHODS

Overall, 250 healthy Tehranian adults were assessed in 2015 for dietary intakes of NO₃ and NO₂ and its serum and urine concentration. Food composition values for NO₃ and NO₂ were derived from a recent survey conducted on frequently consumed food items among Iranians. The correlation of dietary intakes of NO₃/NO₂ and its urinary and serum values was evaluated.

RESULTS

Mean (±SD) intakes of dietary NO₃ and NO₂ were 505±160 and 7.7±2.2 mg/d, respectively. The correlation coefficient of intake and urinary NO₃ was 0.83 (95% CI=0.56-0.91) and 0.57 (95% CI=0.49-0.67) in men and women, respectively. A moderate agreement was also observed between NO₂ intake and its urinary levels (r=0.27, 95% CI=0.13-0.37, and 0.29, 95% CI=0.17-0.41, in men and women, respectively).

CONCLUSION

Using a national database of NO₃ and NO₂ content of food items along with a valid food frequency questionnaire could provide a valid estimation of dietary intakes of NO₃ in the target population.

Anthropometric Indices as Predictors of Coronary Heart Disease Risk: Joint Modeling of Longitudinal Measurements and Time to Event

BACKGROUND

The prevalence of overweight and obesity have increased dramatically worldwide and together they constitute a major risk factor for coronary heart disease (CHD). The aim of this study was to assess the repeated measurements of body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR) and waist to height ratio (WHtR) in predicting CHD incidence.

METHODS

This longitudinal study was conducted within the framework of the Tehran Lipid and Glucose Study between 1999-2011, on 1959 women and 1371 men participants' ages ≥30 yr, without a history of CVD. A joint modeling approach was utilized for data analysis using R software. The resulting joint model allowed measuring α (quantifies the association between anthropometric indices up to time t and the hazard for CHD event at the same time point).

RESULTS

About 9% of the participants (7.1% of the women and 11.7% of the men) experienced CHD event during follow-up. The results indicated a significant linear increasing trend in BMI, WC, WHR, and WHtR over time (P<0.001). The increased risk of CHD event in females increases with the values of BMI (α= 0.004, P=0.023), WC (α= 0.018, P=0.009), WHR (α= 0.067, P=0.014) and WHtR (α= 0.106, P=0.002). Furthermore, in males the risk of CHD risk increases by the values of BMI (α= 0.005, P=0.032), WC (α= 0.019, P=0.008), WHR (α= 0.043, P=0.015) and WHtR (α= 0.096, P=0.002).

CONCLUSION

By jointly modeling longitudinal data with time-to-event outcomes, our study revealed that WHtR is superior to other indices in predicting CHD incidence.

Incidence and Prevalence of Childhood Obesity in Tehran, Iran in 2011

BACKGROUND

The aim of this study was to determine the incidence and prevalence of obesity in Tehranian children.

METHODS

Data from children participated in Tehran Lipid and Glucose Study (TLGS) were evaluated. Cut off points for definition of obesity was the CDC's standard thresholds of the 95th percentile and 85th percentile for overweight. Prevalence, annual incidence of obesity, cumulative incidence over 10 year and the incidence density (cases per person-years) totally were calculated.

RESULTS

The annual incidence of obesity was 1.9 and 3.4% per year in the first 3 yr and decreased to 0.9 and 2.5% in the last 3 yr of follow-up in girls and boys, respectively. Incidence density rates were in line with cumulative incidence, with a rate of 20.7 per 1000 person-years between the ages of 5.6 and 15.5 yr. The prevalence of obesity was higher among children who had obese parents (P=0.03). Among all ages, across the quartiles of parents' BMI, the prevalence of obesity increased with rising in paternal (P=0.001) or maternal BMI (P=0.004). Physical activity of mothers affected the prevalence of obesity in children at mean ages of 5.3 and 9.1 yr. Across quartiles of mother's physical activity, from heavy to light, the prevalence of obesity increased among children, from 4.4% to 5.9% in children, aged 5.3 (P=0.02) and from 11.6% to 13.0% in children, aged 9.1 yr (P=0.03).

CONCLUSION

Prevalence of obesity among children increased with age. Cumulative incidence of obesity in children who were overweight at baseline was much higher than other children.

Relationship between Diet and Non-alcoholic Fatty Liver Disease: A Review Article

BACKGROUND

Diet plays a key role in the development of non-alcoholic fatty liver disease (NAFLD). The aim of this study was to review systematically observational studies available regarding the relationship between food intakes and NAFLD.

METHODS

We searched Scopus, PubMed, and Cochrane Library databases to identify English observational studies on food groups, dietary patterns, and NAFLD. Cross-sectional, case-control and cohort studies were selected and then duplication, topic, type of study, study population, variables examined and quality of data reporting of the articles were evaluated.

RESULTS

We identified 2128 studies in the initial search, of which 33 were reviewed in full text and 7 articles were included in this systematic review. Intakes of red meat, fats, and sweets were high whereas consumption of whole grains, fruits and vegetables were less in NAFLD patients. Moreover, there was a positive association between the Western dietary pattern and the risk of NAFLD, while adherence to the Mediterranean diet was significantly associated with the severity of hepatic steatosis.

CONCLUSION

Generally, different food group intakes and dietary patterns are associated with the progression of NAFLD and its risk factors. Because of the many limitations of available studies reviewed on this topic, more prospective studies are suggested.

Seven-Year Changes of Leisure-Time and Occupational Physical Activity among Iranian Adults (Tehran Lipid and Glucose Study)

BACKGROUND

Considering the lack of data available on changes of physical activity over time in Iran, this study was designed to evaluate changes in physical activity levels among Iranian adults over a median 6.5 yr period.

METHODS

In this population-based cohort study, 3515 participants, aged ≥ 20 yr (2100 females and 1415 males) were followed from phase II (2002-2005) to phase IV (2008-2011) of the Tehran Lipid and Glucose Study. Information on physical activity, both leisure time (LTPA) and occupational (OCPA), was collected using the Modifiable Activity Questionnaire. Scores ≤600 METs-min/wk were considered as having low physical activity. Wilcoxon test was performed for comparing MET values between the two phases. McNemar test was used to evaluate differences between paired qualitative data.

RESULTS

In both phases, 59.8% of adults were women, with mean±SD age 44.3±14.6 and 50.9±14.6 yr, in phases II and IV respectively. The prevalence of low physical activity decreased significantly in the follow up period (from 45.9% in phase II to 42.6% in phase IV, P=0.004). In both genders, a non-significant decrease in OCPA was observed, However, there was a significant decrease in LTPA among women (P=0.031), but not in men.

CONCLUSION

Despite the high levels of physical activity in Tehranian adults, a decreasing trend was observed. Significant decrease in LTPA among women indicates the urgent need to target women for prevention and implementation of public educational programs to promote physical activity levels and LTPA in particular, to compensate the reduction in OCPA.

Association of Metabolic Syndrome with Body Fat Percent, Anthropometric Indices in 10 To 18 Year Old Adolescents

BACKGROUND

Our aim was to evaluate the association of metabolic syndrome (MetS) and its components with body fat percentage (BFP) and anthropometric indicesin10 to 18year old adolescents.

METHODS

This was a cross-sectional study conducted on 134 Tehranian adolescents, aged 10 to 18 years (66 boys and 68 girls) in 2007. The MetS definition proposed by Cook et al. was used. Logistic regression was used to determine the relationship of MetS and its components with body mass index (BMI), waist circumference (WC), waist to height ratio (WHtR), and BFP. Using the areas under the receiver operating characteristic (ROC) curve, the discriminatory ability of anthropometric measurements and BFP was evaluated.

RESULTS

The mean±SD forage of boys and girls was14.5±2.3and13.0±2.9 years, respectively (P=0.001); the prevalence of MetS in these groups was 32.3 and6.5%, respectively (P=0.001). After adjusting for sex and physical activity, the highest odds ratios (95% CI) for MetS and hypertriglyceridemia were found for WC, 6.27 (2.63-14.94; P<0.05)and 3.14 (1.87-5.27; P<0.05), respectively, and those for low HDL-C and hypertension were found for BMI, 2.91 (1.73-4.90; P<0.05)and 2.26 (1.27-4.02; P=0.05), respectively. After adjusting for sex and physical activity, the highest area under ROC curve for MetS and hypertriglyceridemia was seen for WC (P=0.001), for hypertension it was seen for BMI (P=0.001), and for low HDL-C it was observed for both WC and BMI (P=0.001).

CONCLUSIONS

In adolescents, WC was the best predictor of MetS and hypertriglyceridemia, BMI was the best predictor of hypertension, and WC and BMI were the best predictors for low HDL-C.