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Back ground: Iodine deficiency is one of the important factors in increasing the recall rate in congenital hypothyroidism (CH) screening programs. The present study assessed whether the iodine status of the general population may predict the recall rate or vice versa. Methods: In the current national study, among 1,382,229 live births delivered between March 2010 and March 2011, 1,288,237 neonates were screened for detecting CH by TSH (thyroid stimulating hormone) measurement via heel prick sampling. Simultaneously, a total of 11,280 school-aged children, aged 7–8 years, were selected using random multi-cluster sampling for measurement of urinary iodine. Results: A negative correlation was found between median urinary iodine (MUI) and the recall rate (r = −0.33, p = 0.03). No correlation was found between MUIC (median urinary iodine concentration) and the incidence rate of CH. Linear regression analysis showed a 0.1% increase in the recall rate for a one unit decrease in MUIC (β = −0.11, 95% CI: −0.2, −0.1, p = 0.03). MUIC, at a cut-off point of 144.7 µg/L, was predictive for a recall rate < 3% (p = 0.05). Conclusion: Frequencies of TSH ≥ 5 mU/L may be a more sensitive indicator for iodine status during pregnancy rather than in the general population. As higher recall rates reflect inadequate iodine nutrition, sufficient iodine supplementation is needed to reduce the recall rate in such communities.

To determine cutoff points of anthropometric variables for predicting incident cardiovascular disease (CVD) in Iranian adults.It is a population-based longitudinal study.A total of 1614 men and 2006 women, agedor =40 years, free of CVD at baseline were included in the study.Body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and cardiovascular risks were assessed. Incident CVD was ascertained over a median of 7.6 years follow-up. The adjusted hazard ratios (HRs) for CVD were calculated for 1 s.d. change in all obesity variables using Cox proportional hazards regression analysis. Receiver operator characteristic (ROC) curve analysis was used as the method of defining the points of the maximum sum of sensitivity and specificity (MAXss) of each variable as a predictor of CVD.We found 333 CVD events during follow-up. The risk-factor-adjusted HRs were significant for all anthropometric variables in males and WHR in females and were 1.19, 1.24, 1.21 and 1.24 for BMI, WC, WHR and WHtR in males and 1.27 for WHR in females, respectively (all P0.05). ROC analysis showed the highest area under curve (AUC) for WHR, WHtR and WC, followed by BMI in males and both genders agedor =60 years. In females, WHR and WHtR had the highest AUC, followed by WC and BMI. Among those60 years old, all the anthropometric variables showed same CVD predicting power. The cutoff values (MAXss) for CVD prediction in males and females were BMIs 26.95 and 29.19 kg m(-2),WCs 94.5 and 94.5 cm, WHRs 0.95 and 0.90, and WHtR 0.55 and 0.62, respectively.There was no difference between central obesity variables in predicting CVD in males, whereas in females WHR and WHtR were more appropriate. The cutoff values of anthropometric variables were higher in the Iranian than in other Asian populations.

Background: Despite the high prevalence of diabetes, limited information is available about the impact of impaired glucose regulation on the cardiovascular disease (CVD) risk among Middle East populations. Aims: To determine the risk of CVD in an urban Iranian population according to glucose tolerance status. Material and methods: The study population consisted of 1752 men and 2273 women, aged ≥40 yr, free of CVD at baseline. Incident CVD was ascertained over a median of 7.6 yr of follow-up. Results: A total of 340 CVD events occurred (197 in men and 143 in women). At baseline, there was no difference between newly diagnosed and known diabetes regarding the Prospective Cardiovascular Munster (PROCAM) risk score and prevalence of metabolic syndrome in both genders. Applying the 1997 American Diabetes Association (ADA) criteria, compared with those with normal glucose tolerance, after controlling traditional risk factors, hazard ratios (HR) and 95% confidence intervals (95% CI) for CVD in women with known and newly diagnosed diabetes were 3.30 (2.09–5.21) and 1.93 (1.16–3.21) and the corresponding values for men were 1.90 (1.11–3.25) and 1.69 (1.12–2.54), respectively. Impaired fasting glucose or impaired glucose tolerance was associated with 56% increased risk of CVD in women (HR 1.56, 95% CI 1.00 to 2.45), in the age-adjusted analysis, considering the 2003 ADA criteria. Conclusions: All diabetic subjects, whether newly diagnosed or known cases, should receive intensive primary prevention for CVD regardless of risk factors, in particular females with abnormal glucose regulation.

To determine whether triglyceride/high-density lipoprotein cholesterol ratio (TG/HDL-C), which has been shown to be an indicator of the metabolic syndrome (MetS) and insulin resistance, can predict coronary heart disease (CHD) independently of total cholesterol (TC) and other risk factors in an Iranian population with a high prevalence of MetS and low HDL-C.Between February 1999 and August 2001, 1824 menor =40 years old, free of clinical cardiovascular diseases at baseline, were followed. Baseline measurements included serum level of TC, HDL-C, TG and risk factors for CHD including age, systolic and diastolic blood pressure, body mass index, waist circumference, diabetes, smoking and a family history of premature cardiovascular diseases. During a median follow up of 6.5 years until March 2007 (11,316 person-years at risk), a total of 163 new CHD events (27 fatal and 136 nonfatal) occurred. The prevalence of MetS in subjects with TG/HDL-Cor =6.9 (top quartile) reached 63.6% versus 3.0% in those with TG/HDL-C2.8 (low quartile). According to a stepwise Cox proportional hazard model, including TG and TG/HDL-C quartiles, with TC and other risk factors, men in the top quartile of TG/HDL-C relative to the first quartile had a significant hazard ratio (HR) of 1.75 (95% CI, 1.02-3.00), while TG did not remain in the model.The evaluation of TG/HDL-C ratio should be considered for CHD risk prediction in our male population with a high prevalence of MetS.

Controversial findings are reported on the risk of cardiovascular disease in chronic kidney disease (CKD). There are some interactions between CKD and other metabolic disorders including metabolic syndrome (MS) and obesity regarding coronary heart disease (CHD) outcomes.A total of 2823 men and 3684 women aged 30 years and older, without cardiovascular disease, were followed for 10 years. Multivariable adjusted hazard ratio of CHD was estimated for those who developed CKD, MS or both by sex and body mass index levels below and above 27 kg/m2. The interaction term of CKD and MS and also CKD-MS components were assessed in the Cox proportional hazard models as well.Chronic kidney disease without MS, showed a significant effect on CHD only in participants with low body mass index (hazard ratio, 2.06; 95% confidence interval, 1.28 to 3.31 in the men and hazard ratio, 2.56; 95% confidence interval, 1.04 to 6.31 in the women). The joint effect of CKD and MS decreased to one-third of their multiplicative effect in this subgroup, indicating a negative interaction between CKD, MS, and Obesity. The same interaction was observed between CKD and hypertension in both sexes and CKD and type 2 diabetes mellitus in the men.Our results showed that CKD was an independent risk factor for CHD only in nonobese individuals; however, its risk was wiped out when joined to MS. Following the concept of "obesity paradox," the term of "risk factors paradox" also needs more attention.

To identify risk factors for cardiovascular disease (CVD) and mortality events in patients with type 2 diabetes and to calculate their population attributable fraction among a representative Iranian population.A total of 1198 patients with type 2 diabetes (504 men and 694 women), aged ≥30 years, without prevalent CVD, with a median follow-up of 10 years were included in current study. To examine the association between risk factors and their outcomes, multivariate sex-adjusted Cox proportional hazard regression models were used.During the study, 281 and 172 participants experienced CVD and all-cause mortality events, respectively. Regarding CVD events, fasting plasma glucose (FPG) level of 7.22-10 mmol/L [hazard ratio (HR): 1.46, 95% CI 1.12-1.96], FPG level ≥10 mmol/L (HR 2.04, 1.53-2.72), hypertension (HR 1.65, 1.28-2.13), hypercholesterolaemia (HR 1.96, 1.40-2.75) and high waist to hip ratio (HR 1.30, 0.99-1.70; p = 0.051) were significant predictors, and corresponding population attributable fractions were 9.76, 17.84, 23.26, 41.63 and 14.76%, respectively. Considering all-cause mortality events, hypertension (HR 1.70, 1.23-2.36), FPG level ≥10 mmol/L (HR 2.31, 1.55-3.20) and smoking (HR 1.45, 1.03-2.04) were significant predictors, and corresponding population attributable fractions were 25.81, 20.88 and 11.18%, respectively. Meanwhile, being overweight or obese was associated with lower all-cause and CVD mortality events.Among modifiable risk factors in patients with type 2 diabetes, hypercholesterolaemia and central adiposity for CVD, smoking for mortality events and hypertension and poor glycaemic control for both outcomes need to be paid most attention by healthcare professionals. Copyright © 2016 John WileySons, Ltd.

Many cell signaling pathways essential for normal stem cell development are involved in cancer initiation and progression. In the present study, motivated by a possible contribution of reprogramming process in induction of cancer, we compared the expression level of main genes involved in iPS generation, i.e., miR-302, miR-145, SOX2, c-MYC, and P21, in a series of tumor and non-tumor tissues of stomach. A total number of 34 tumors and their matched non-tumor (as control) gastric surgical specimens were obtained. The expression of the candidate genes was evaluated by using real-time PCR and immunohistochemistry (IHC) techniques. Our data revealed a significant downregulation of miR-302b, P21, and miR-145 genes in intestinal and SOX2 gene in diffuse type of tumor samples. SOX2, but not the other genes, showed a significant downregulation in both proximal (cardia and fundus) and distal (body and antrum) sites of stomach. Based on receiver-operating characteristic (ROC) analyses, the highest total area under the curve (AUC) was found for SOX2 (AUC = 82 %, P

Use of single measurement of risk factors can distort their estimated effects, due to random error in measurements. The aim of this study was to examine the extent of underestimation in the estimated effect of common variables in physical exam i.e. systolic and diastolic blood pressure (SBP, DBP) and body mass index (BMI) on cardiovascular diseases in Tehran Lipid and Glucose Study (TLGS).A subsample (1167 men and 1786 women) of the original cohort, who had replicate measures of the variables in triennial interval, was used to calculate the regression dilution ratios (RDRs) in men and women. RDRs were determined by parametric and nonparametric methods. Hazard ratios (HR) of risk factors, per one standard deviation change, were corrected for regression dilution bias.The estimated RDRs by parametric method in men and women were 45% and 35% for SBP and 54% and 64% for DBP respectively. There were 26% and 25% underestimation in HR of SBP and 23% and 33% in HR of DBP in men and women. The corresponding underestimation for BMI was about 8%. RDRs of men and women and in age groups by both methods were fairly similar. They were relatively constant during the 10-year follow-up for SBP and BMI.Using baseline measurements of blood pressure underestimate its real association with CVD events and the estimated HRs. The underestimations are independent of age and sex, and it can be fairly constant in short to moderate time intervals.

Background: The ACC/AHA released a newguideline on the assessment of cardiovascular risk andmanagement of hypercholesterolemia that some controversy exists concerning its usefulness. We examined the clinical usefulness of this guideline in a high incidence population using novel measures. Methods: First, we validated the new risk equation in a cohort of 2372 men and 2781 women aged 40-75 years. Then, high risk individuals for cardiovascular diseases (CVDs) were identified according to the ACC/AHA guideline at baseline (as a predictor) and CVD outcomes were detected during a 10-year follow-up. Discrimination of the guidelinewas quantified and the quality of decisions was evaluated by Net Benefit Fraction index considering the harm, for false-positive, and benefit, for true-positive predictions. Finally, net number needed to treat (NNT) for statin was estimated, using test tradeoff index, in diabetic and non-diabetic subjects. Results: During follow-up, 726 CVD events including 298 hard CVDs occurred. The equation overestimated the risk by 57% in men and 48% in women. Based on the guideline, 73% of men and 44% of women were eligible for statin therapy. The lowest sensitivity was detected for intensive treatment in non-diabetic subgroups (82% in men and 41% in women; corresponding specificity, 52% and 90% respectively). The guideline had a significant net benefit for both moderate and intensive treatment, which resulted in estimated NNTs ranged 5-55; however, net benefit of intensive therapy was uncertain in non-diabetic women. Conclusions: We objectively showed that the ACC/AHA recommendations could be useful in our population but with some overtreatment in women. (C) 2015 Elsevier Ireland Ltd. All rights reserved.

BACKGROUND: Treatment of cardiovascular risk factors based on disease risk depends on valid risk prediction equations. We aimed to develop, and apply in example countries, a risk prediction equation for cardiovascular disease (consisting here of coronary heart disease and stroke) that can be recalibrated and updated for application in different countries with routinely available information.METHODS: We used data from eight prospective cohort studies to estimate coefficients of the risk equation with proportional hazard regressions. The risk prediction equation included smoking, blood pressure, diabetes, and total cholesterol, and allowed the effects of sex and age on cardiovascular disease to vary between cohorts or countries. We developed risk equations for fatal cardiovascular disease and for fatal plus non-fatal cardiovascular disease. We validated the risk equations internally and also using data from three cohorts that were not used to create the equations. We then used the risk prediction equation and data from recent (2006 or later) national health surveys to estimate the proportion of the population at different levels of cardiovascular disease risk in 11 countries from different world regions (China, Czech Republic, Denmark, England, Iran, Japan, Malawi, Mexico, South Korea, Spain, and USA).FINDINGS: The risk score discriminated well in internal and external validations, with C statistics generally 70% or more. At any age and risk factor level, the estimated 10 year fatal cardiovascular disease risk varied substantially between countries. The prevalence of people at high risk of fatal cardiovascular disease was lowest in South Korea, Spain, and Denmark, where only 5-10% of men and women had more than a 10% risk, and 62-77% of men and 79-82% of women had less than a 3% risk. Conversely, the proportion of people at high risk of fatal cardiovascular disease was largest in China and Mexico. In China, 33% of men and 28% of women had a 10-year risk of fatal cardiovascular disease of 10% or more, whereas in Mexico, the prevalence of this high risk was 16% for men and 11% for women. The prevalence of less than a 3% risk was 37% for men and 42% for women in China, and 55% for men and 69% for women in Mexico.INTERPRETATION: We developed a cardiovascular disease risk equation that can be recalibrated for application in different countries with routinely available information. The estimated percentage of people at high risk of fatal cardiovascular disease was higher in low-income and middle-income countries than in high-income countries.FUNDING: US National Institutes of Health, UK Medical Research Council, Wellcome Trust.

Hirsutism is the most common indicator of hyperandrogenism. Both, the sensitivity of the patients to the serum androgen levels and the responsiveness of women to the perceived excess hair growth vary among different populations. This report elaborates the relationship between the woman's discerned abnormal hair growths with the clinical diagnosis of hirsutism.The survey was conducted among 1160 women aged 18-45 and randomly selected from Tehran Lipid and Glucose Study for further detailed assessment of Hirsutism; using the m-FG scoring method. Data gathering was performed by interviews and physical examinations. The receiver operating characteristic curve was drawn and the new cutoff value, sensitivity, specificity and concordance percentage were calculated.The results demonstrated that among 12 androgen-dependent body areas, the chin skin had the highest area under curve of 0.81 (CI; 0.78-0.84). According to the patient's evaluation, a threshold point of 4 had the optimum concordance percentage of 0.77 with the modified Ferriman-Gallwey scoring system.Patient's self-identification of excess terminal hair based on the chin area has great sensitivity and reliability in predicting the clinical hirsutism.

Population Attributable Fraction (PAF) is one of the most practical measures for estimating the burden of risk factors with some challenges in its calculation. Cardiovascular disease (CVD) is the first cause of death worldwide and the estimation of accurate PAFs for CVD risk factors is of great importance in conducting preventive strategies. Our aim was to estimate the PAFs of CVD risk factors via direct, i.e. based on regression models, and indirect, i.e. using related equations, methods.Participants (3200 males and 4245 females aged ≥30 yr) without history of CVD were selected from the population-based cohort of Tehran Lipid and Glucose Study (TLGS). Hazard ratio (HR) and Odds ratio (OR) of conventional risk factors were calculated for CVD events after ten yr of follow-up. Levin's and Miettinen's equations were applied to indirectly estimate the PAFs and average PAF was directly derived from logistic regression model.The sum of PAFs resulted from indirect estimations reached to more than 100% (around 200% and 150% based on Levin's and Miettinen's formula respectively). The direct estimation attributed 80% and 86% of burden of CVD events to conventional risk factors in men and women respectively. The rank and pattern of PAFs of risk factors was somehow different among different methods.Estimating priorities of risk factors may differ in different methods for calculating PAF. This study provides evidence on the more expediency of direct method over indirect ways when individual data is available through a population-based cohort.

The relationship among components of metabolic syndrome (MetS) and their association with diabetes is unclear in West Asia. The aim of the present study was to conduct factor analysis of MetS components and the effect these factors have on the incidence of type 2 diabetes (T2D) in a population-based cohort study of the Tehran Lipid and Glucose Study (TLGS).The present study enrolled 1861 men and 2706 women (20-60 years of age), from Tehran (Iran) who were free of diabetes at baseline and followed them for 10 years. A principal component analysis was performed to extract standardized factors from MetS components. Logistic regression was used to detect associations between the extracted factors and the incidence of diabetes. A propensity score was used to correct differential selection bias resulting from loss to follow-up.Factor analysis identified three factors (blood pressure, lipids and glycemia). Waist circumference was shared in three all factors. Blood pressure, lipids and glycemia were related to the incidence of diabetes with odds ratios (95% confidence intervals) of 2.23 (1.31-3.78), 1.89 (1.27-3.67), and 7.54 (4.09-13.91), respectively, in men and 2.13 (1.34-3.40), 2.06 (1.35-3.15), and 13.91 (7.29-26.51), respectively, in women for the third versus the first tertile of these standardized factors.Central adiposity may have a pivotal role in MetS linking other risk factors together. Glycemia had a high impact on the incidence of diabetes, whereas blood pressure and lipid had a similar moderate effect on the incidence of diabetes.

Aims/Hypothesis To investigate secular trends in cardiovascular disease (CVD) risk factors during a decade of follow-up in a Middle Eastern cohort, and to compare observed trends between diabetic and non-diabetic populations. Methods In a population of 6181 participants (2622 males and 3559 females), diabetes status and CVD risk factors were evaluated in 4 study phases from 1999–2011. 1045 subjects had type 2 diabetes mellitus at baseline and 5136 participants were diabetes-free. To examine the trends of CVD risk factors, generalized estimation equation models were constructed. The interaction between the diabetes status and each phase of the study was checked in a separate model. Results During the follow-up period diabetic females significantly gained better control of their blood pressure, serum low density lipoprotein cholesterol and general and central obesity measures compared to non-diabetic counterparts, although 60% of them had high BP and 64% had high serum LDL-C levels till the end of the study. Diabetic males however, experienced significantly better control on their serum LDL-C and general and central obesity measures compared to their non-diabetic controls; but 24% of them were still smoker, 63% had high BP and 60% had high serum LDL-C levels at the end of the follow-up (all Ps interaction

Objective To investigate the population-based incidence of type 2 diabetes and its potential risk factors in a sex-split cohort of Iranian population. Materials and Methods A total of 8400 non-diabetic participants, aged ≥20 years (3620 men and 4780 women) entered the study. Crude and age standardized incidence rates per 1000 person-years were calculated for whole population and each sex separately. Cox proportional hazard models were used to evaluate hazard ratios (HR) and 95% confidence intervals for all potential risk factors in both uni-variable and multivariable models. Results During a median follow-up of 9.5 years, 736 new cases of diabetes were identified, including 433 women and 303 men. The annual crude and age-standardized incidence rates (95% CI) of diabetes in the total population were 10.6 (9.92–11.4) and 9.94 (7.39–13.6) per 1000 person-years of follow-up and the corresponding sex specific rates were 10.2 (9.13–11.4) and 9.36 (5.84–14.92) in men and 11.0 (9.99–12.0) and 10.1 (7.24–13.9) in women, respectively. In the multivariable model, the risk for incident diabetes was significantly associated with fasting and 2 hour post challenge plasma glucose as well as family history of diabetes in both men and women. However, among women, only the contribution of wrist circumference to incident diabetes achieved statistical significance [HR: 1.16 (1.03–1.31)] with waist/height ratio being marginally significant [HR: 1.02 (0.99–1.04)]; while among men, only body mass index was a significant predictor [HR: 1.12 (1.02–1.22)]. Additionally, low education level conferred a higher risk for incident diabetes only among men [HR: 1.80 (1.23–2.36); P for interaction with sex = 0.003]. Conclusion Overall, sex did not significantly modify the impact of risk factors associated with diabetes among Iranian adults; however, among modifiable risk factors, the independent role of lower education and general adiposity in men and central adiposity in women might require different preventive strategies.

To the Editor:We read with interest the recent paper about hepatitis C virus(HCV) clearance in patients with acute HCV infection [1].Weare wondering why authors did not calculate risk ratio insteadof odds ratio (OR) when they have run a cohort study? Theycan present how much is the incidence of HCV clearance and rel-ative risk (RR) of factors affecting on such clearance, which ismore precise than OR and real actual estimation of the strengthof risk factor. Reporting RR besides OR in univariate analysisand then multivariable OR based on logistic regression makes iteasy to interpret multivariable (adjusted) OR regarding ‘‘built-in-bias.’’ When the condition of interest has a high incidenceand prospective data are available, like the study by Mangiaet al. [1], it is usually better to report the RR instead of OR. Imple-menting OR as an estimate of the RR biases it in a direction oppo-site to the null hypothesis; that is, it tends to exaggerate themagnitude of the association. This is called built-in bias whichis negligible when the disease is relatively rare [2]. When theincidence is high; like spontaneous HCV clearance andnon-responders to treatment in the present study, the bias canbe substantial [2]. In other words, built-in bias is responsiblefor the discrepancy between the RR and OR estimates.The value of this bias is equal to:1 q

The Iranian Registry of Clinical Trials (IRCT) was established as a primary registry on December 4 2008 and has registered over 1350 trials by June 2011. Many researchers are still unaware of the need for registration of trials before recruiting the first patient and the proportion of retrospectively registered trials is likely to grow until this awareness increases. We sought to investigate the timing of the registrations in IRCT and to explore strategies to overcome this. We used all data in the IRCT database and extracted the date of registration, as well as the dates for the start and the end of recruitment. We categorized trials into 4 groups: those registered before the start of patient enrolment, within 30 days of enrolment, after 30 days but before the end of recruitment, and after the end of recruitment. The proportion of trials in each category was calculated by calendar year. The number of registered trials increased from 26 in the 3 months leading to 2009 to 181 in 2009, 772 in 2010 and 376 in the first 5 months of 2011 (estimate by end of year = 947). The proportions of trials registered after the end of patient recruitment were 55%, 58% and 62% in 2009, 2010 and 2011 respectively. On average, 6.4% of trials were registered within 30 days from the start of patient recruitment and 27% in the time between then and the end of recruitment. The rapid increase in the number of registered trials is an indication of strong implementation of the registration policy. This comes partly at the expense of an increased proportion of retrospective registrations. While this may be understandable at the beginning, it is clearly not acceptable and measures should be adopted to increase the proportion of prospectively registered trials and to make trial registration an integral part of the research culture.

Aims To examine the nature of the association between 25-hydroxyvitamin D [25(OH)D] and newly diagnosed type 2 diabetes. Methods Serum 25(OH)D concentrations were measured for 761 participants (aged 20–83 years) in the Tehran Lipid and Glucose Study, selected for a 1-to-3 nested case–control study. Cases were 191 cases of Type 2 diabetes diagnosed during a median follow-up of 3.6 years. A total of 570 participants were matched with these cases with regard to age, sex, BMI, and month of entering the study. Diabetes was defined according to the American Diabetes Association criteria, 2003. Serum 25(OH)D was measured using the enzyme immunoassay method. Odds ratios for Type 2 diabetes were obtained from conditional logistic regression models for tertiles of serum 25(OH)D concentrations [tertile-1: 2.82–11.02 (reference), tertile-2: 11.03–21.80, and tertile-3: ≥ 21.82 ng/ml]. The multivariate model was adjusted for age, sex, family history of diabetes, systolic blood pressure, triglyceride-to- HDL cholesterol ratio, waist-to-height ratio, lifestyle modification intervention, leisure time physical activity, and fasting plasma glucose at baseline. Non-linearity in the associations between baseline 25(OH)D and Type 2 diabetes, was examined by using restricted cubic splines. Results Unadjusted odds ratios (95% confidence intervals) of diabetes were 0.73 (0.74–1.13), 0.54 (0.34–0.85) for the second and third tertiles, respectively. Multivariate adjusted odds ratios were 0.47 (0.25–0.90) and 0.43 (0.23–0.82), respectively. Below the cutoff of ~ 10 ng/ml the risk of newly diagnosed Type 2 diabetes increased dramatically. Discussion It was found that 25(OH)D concentrations contributed to the Type 2 diabetes incidence rate in a non-linear fashion, with the risk beginning to increase sharply for values

Our objective was to examine whether wrist circumference is associated with incident type 2 diabetes mellitus, independently of general (body mass index [BMI]) or central (waist circumference [WC]) adiposity measures in a cohort of an Iranian adult population.A total of 9330 subjects ≥ 20 years of age were included in the cross-sectional study. For prospective analysis, subjects with prevalent diabetes were excluded, leaving 6393 subjects (2716 males and 3677 females). The standard 2-hour postchallenge plasma glucose test was performed at baseline and during follow-up. Cox regression analysis was used to estimate the hazard ratio of diabetes for wrist circumference.During a mean follow-up of 8.8 years, 649 new cases of diabetes occurred. At baseline, using linear regression models, we showed significant linear associations between wrist circumference and diabetes risk factors in both genders, and this association remained significant after controlling for BMI or WC among females. In prospective evaluation, wrist circumference was significantly associated with incident diabetes (multivariable-adjusted hazard ratio = 1.17 [1.03-1.32] and 1.31 [1.18-1.45] for males and females, respectively). After controlling for the subjects' BMI or WC, wrist circumference was an independent predictor of diabetes only among females. Wrist circumference was an independent predictor of metabolic syndrome only among women even after adjustment for BMI, WC, or both.Wrist circumference is a significant predictor of diabetes in both genders of adult population. However, its predictability is independent of BMI or WC only among females. Because of its simple and easy-to-detect nature, wrist circumference could be considered as a new anthropometric assessment for prediction of type 2 diabetes and metabolic syndrome.

Background Data about the risk factors of stroke are sparse in the Middle East populations. We aimed to determine the potential risk factors and their population attributable fraction (PAF) for stroke in an Iranian population. Methods A cohort Study consisted of 1089 men and 1289 women, with mean (SD) ages of 61.1(7.6) and 59.0(6.7) years, respectively. Cox regression was implemented to estimate the hazard ratio (HR) of each risk factor for stroke events in a stepwise method. We calculated a multivariate adjusted population attributable fraction (PAF) for any risk factors remained in the model. Results During 9.3 years of follow-up, 69 events of stroke occurred with incidence rates of 4.5 (95% CI: 3.3-6.0) and 2.5 (1.7-3.6) in 1000 person-years for men and women respectively. Among potential risk factors, only age ≥ 65 years (HR: 2.03, CI: 1.24-3.31), male gender (HR: 2.00, CI: 1.16-3.43), hypertension (HR: 3.03, CI: 1.76-5.22), diabetes mellitus (HR: 2.18, CI: 1.34-3.56), and chronic kidney disease (CKD) (HR: 2.01, CI: 1.22-3.33), were independently associated with increased risk of stroke events in the total population. A paired homogeneity test showed that the hazard ratio of CKD did not differ from other independent risk factors. The PAFs were 29.7% and 25% for male gender and age ≥ 65 as non-modifiable and 48.6%, 29.1% and 22.0% for hypertension, CKD and diabetes as modifiable risk factors respectively. Conclusion Following this population based study of Iranians, we demonstrated that among modifiable risk factors, CKD as well as hypertension and diabetes are the strongest independent predictors of stroke.

Objective: To explore the relationship between age-specific anti-Müllerian hormone level, as a predictor of ovarian reserve status, and electrocardiographic silent coronary artery disease in a population-based, prospective cohort, the Tehran Lipid and Glucose Study. Methods: For the present study, 1015 reproductive-aged participants in the Tehran Lipid and Glucose Study met our eligibility criteria. According to the Whitehall criteria, silent coronary artery disease was defined as an electrocardiogram showing possible or probable coronary heart disease using Minnesota codes. By excluding those with a history of coronary heart disease and silent coronary artery disease at the initiation of the study (n = 49), there were 108 events of silent coronary artery disease at electrocardiograms among 752 women followed for 9.5 ± 0.9 years (missing data: n = 214); the association between this outcome with age-specific anti-Müllerian hormone levels was explored after adjustment for confounding variables using logistic regression analysis. Cardiovascular disease risk scores were assessed for all participants using the guidelines of the American College of Cardiology and the American Heart Association. Results: There were 108 events of silent coronary artery disease over the 10-year follow-up. Logistic regression analysis, considering age-specific anti-Müllerian hormone and atherosclerotic cardiovascular disease risk score as independent variables, revealed an odds ratio of 1.146 (95% confidence interval 1.008–1.303) for cardiovascular disease risk score (p = 0.038) and odds ratio of 1.002 (95% confidence interval 0.996–1.009) for age-specific anti-Müllerian hormone (p = 0.526). Conclusion: No association has been found between age-specific anti-Müllerian hormone levels and events of silent coronary artery disease in a 10-year follow-up of reproductive-aged women.

To examine the change in general and central adiposity measures as a predictor of incident dysglycemia during a 6-year follow-up.A total of 4029 (2333 women and 1696 men) non-dysglycemic Iranians aged ≥ 20 years, underwent standard fasting and 2-h post-challenge plasma glucose tests at baseline and follow-up.During follow-up, 458 new cases of dysglycemia occurred. In multivariable models including baseline values of each anthropometric measure, odds ratios (ORs) for dysglycemia incidence corresponding to a 1-SD increase in changes of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and hip circumference (HC), were 1.32, 1.56, 1.39, 1.51 and 1.39 for men and 1.59, 1.50, 1.37, 1.47, and 1.38, for women, respectively (all P0.05). After controlling for weight change and WC change among men and women, respectively, HC change did not remain as a predictor. Using the paired homogeneity test, there was no superiority for changes in central obesity measures compared to changes in BMI to predict dysglycemia.The association between HC changes and incident dysglycemia was dependent upon changes in central and general adiposity measures, where the former did not have higher predictability than the latter in prediction of dysglycemia.

Background: Specific vaccine therapies have been proposed recently as possible alternative treatment modalities to interferon and antiviral drugs to enhance the immune response in HBV chronic carriers through induction of T cell activity which can lead to control viremia. To assess the efficacy of long term intradermal (ID) hepatitis B virus (HBV) vaccination with double standard dose as an active immunotherapy in elimination of HBV infection in chronic hepatitis B carriers. Materials and Methods: This double-blinded randomized clinical trial was conducted on all HBsAg positive patients. Among them 80 immunotolerant patients were recruited and randomly allocated to alternate study groups (vaccination or placebo) consecutively. Eligible healthy carriers in group 1 were assigned to vaccinate with six ID injections of the Heberbiovac HB vaccine at 30-day intervals and with double standard doses (2cc) in two forearms. Controls received normal saline with the same setting as a placebo. The mean ALT levels, detectable HBV DNA and seroconversion to anti-hepatitis B e antigen (anti-HBe) and anti hepatitis B surface antigen (anti-HBsAb) compared between groups at the beginning and the 6th and 12th months. Results: No significant difference was found in the mean ALT values, the clearance of HBV DNA, seroconversion from HBeAg to HBeAb and developing of HBsAb between vaccinated and control group at the end of the 6th and 12th months (P>0.05). Conclusion: Intradermal administration, even with double standard dose, is not an efficient treatment in the elimination of virus in chronic carriers of HBV.

Objective Prehypertension is associated with cardiovascular disease (CVD). There is no study to examine the incidence and risk factors of prehypertension in a sex stratified setting. The aim of this study was to examine the effect modification of sex for different risk factors which predicts the progression from normotension to prehypertension in a Middle East population-based cohort, during a median follow-up of 9.2 years. Methods A multivariate Cox analysis was performed among 1466 and 2131 Iranian men and women, respectively, who were free of prehypertension, hypertension, CVD and diabetes at baseline and free of incident hypertension without preceding prehypertension at follow-up. Incident prehypertension at follow-up was defined as systolic blood pressure (SBP) of 120–139 mmHg and/or diastolic blood pressure (DBP) of 80–89 mmHg. Results Overall, 1440 new cases of prehypertension were identified resulting in an incidence rate of 593/10000 person-years; the corresponding values for women and men were 489/10000 and 764/10000person-years, respectively. There were significant interactions between gender with age, DBP, waist-to-hip-ratio (WHpR) and estimated glomerular filtration rate (eGFR) (all P-values

OBJECTIVE: The aim of this study was to evaluate the validity of cause of death stated in death certificates in Tehran using outcome measures of the Tehran Lipid and Glucose Study (TLGS), an ongoing prospective cohort study. METHODS: The cohort was established in 1999 in a population of 15005 people, 3 years old and over, living in Tehran; 3551 individuals were added to this population three years later. As part of cohort's outcome measures, deaths occurring in the cohort are investigated by a panel of medical specialists (Cohort Outcome Panel-COP) and underlying cause of death is determined for each death. The cause of death assigned in a deceased's original death certificate was evaluated against the cause of death determined by COP and sensitivity and positive predictive values (PPV) were determined. In addition, determinants of assigning accurate underlying cause of death were determined using logistic regression model. RESULT: A total of 231 death certificates were evaluated. The original death certificates over reported deaths due to neoplasms and underreported death due to circulatory system and transport accidents. Neoplasms with sensitivity of 0.91 and PPV of 0.71 were the most valid category. The disease of circulatory system showed moderate degree of validity with sensitivity of 0.67 and PPV of 0.78. The result of logistic regression indicated if the death certificate is issued by a general practitioner, there is 2.3 (95% CI 1.1, 5.1) times chance of being misclassified compared with when it is issued by a specialist. If the deceased is more than 60 years, the chance of misclassification would be 2.5 times (95% CI of 1.1, 5.9) compared with when the deceased is less than 60 years. Language: en

Aims We examined hypertriglyceridemic waist (HTGW) predictability for CVD and mortality. Methods Among Tehran Lipid and Glucose Study's participants aged ≥30 (n=8071), we selected those who participated in the follow-up study until 20-March-2009 (n=7154). After exclusions (320 missing data on waist circumference or triglycerides), 6834 (3830 women) participants remained eligible with a total of 59,873 person-year follow-up. When CVD was outcome, we further excluded 426 participants with history of previous CVD. Results All-cause mortality, CVD mortality, and incident CVD rate among men (per 1000-person-year) were 7.9 (95% CIs: 6.9–9.1), 4.1 (95% CIs: 3.4–5.0), and 13.0 (95% CIs: 11.7–14.6), respectively. Among women, corresponding figures were 3.7 (95% CIs: 3.1–4.4), 1.7 (95% CIs: 1.3–2.1), and 7.3 (95% CIs: 6.4–8.3), respectively. After adjustment for potential confounders, HTGW came to be inversely associated with all-cause mortality among both men (HR 0.384, 95% CIs 0.281–0.526) and women (HR 0.642, 95% CIs 0.430–0.958). Multivariate adjusted HR (95% CIs) of HTGW for CVD mortality was 0.453 (95% CIs 0.298–0.688) among men and 0.760 (95% CIs 0.431–1.338) among women. HTGW increased the age-adjusted risk of incident CVD, among both men (40%) and women (97%). The multivariate hazard ratio of HTGW for incident CVD was 0.945 (95% CIs 0.746–0.1.198, P value=0.640) among men and 1.470 among women (HR 95% CIs 1.111–1.944, P value=0.007). Conclusion HTGW was the point of divergence for prediction of CVD vs. mortality. HTGW, despite its predictive value for CVD, might not help in capturing risk of all-cause or CVD mortality. Individuals without HTGW constitute a heterogeneous subgroup with a jumble of risk factors that put them at risk for all-cause or CVD mortality.

Objective Following the reforms in 1985 in which medical education was integrated into the National Health Service, we have witnessed an increase in teaching, training, and research capacity, improvement in quality of services, and a major boost in medical research in Iran. Following the surge in research activity, the need for public registration of clinical trials was raised within academic circles, particularly after the initiative by the International Committee of Medical Journal Editors in 2004. Method In line with this global movement, the Iranian Registry of Clinical Trials was developed by a team of Iranian researchers with support from the Ministry of Health and Medical Education. Results In our experience, the challenges for developing a national registry for clinical trials are: (i) choosing a committed, versatile leader with the skills and expertise to work and communicate with a variety of stakeholders and other people involved in the process; (ii) securing the necessary resources and political support to minimize resistance and act as a positive force for implementing changes; (iii) developing strong liaison between the information technology team and website administrators to develop a highly functioning website; and (iv) developing the culture of transparency within society in general, and the research community in particular, which goes far beyond setting up a registry. Conclusion The Iranian Registry of Clinical Trials has made a good start, and should fulfill its mission of providing an accessible source of information for the general public and researchers. This is the goal we have set ourselves.

Elevated blood pressure (BP) may lead to incident diabetes. However, data about the effect of different BP components on incident diabetes in Middle Eastern women is lacking. We evaluated systolic BP (SBP), diastolic BP (DBP), pulse pressure (PP) and mean arterial pressure (MAP) as independent predictors of diabetes in Iranian women. We performed a population-based prospective study among 3028 non-diabetic women, aged ⩾20 years. Odds ratios (ORs) of diabetes were calculated for every 1 s.d. increase in SBP, DBP, PP and MAP. During ≈6 years of follow-up, 220 women developed diabetes. There were significant interactions between family history of diabetes and SBP, PP and MAP (P⩽0.01) in predicting incident diabetes. In women without a family history of diabetes, all BP components were significantly associated with diabetes in the age-adjusted model; the risk factor-adjusted ORs were significant (P

Introduction Net benefit (NB) has been suggested to verify the clinical usefulness of a model beyond its discrimination and calibration but it has a complex meaning in prediction models. Here we define net benefit fraction (NBF) using Population Attributable Fraction (PAF) index. Methods According to Vickers and Elkin (2006), in models that predict diseases to treat high risk individuals, NB is defined as true positive (TP) rate minus weighted false positive (wFP) rate; the weight is the odds at the threshold probability for treatment (Pt/[1-Pt]). Dividing NB by its maximum, incidence of disease, gives the portion of incidence prevented by the treatment. A shortcoming of NB is that it assumes the treatment reduces the incidence in TPs to zero. On the other hand, PAF is defined as reduction of the risk to below the threshold, that is, to that of low risk population. However, PAF does not take into account the false positives. Therefore, we suggest NBF calculated as PAF minus wFP rate, the latter divided by incidence. We applied the method to calculate the clinical performance of Framingham risk function at routine threshold probability of 20% to predict cardiovascular diseases in a population based cohort of 6224 Iranians aged 30–74 years with 10-year follow-up. Results dividing NB by incidence resulted 17% and PAF shows 43% decrease in incidence, but NBF shows just 8% advantage for treatment according to the model. Conclusion NBF seems to be a challengeable issue in policy making using risk functions.

Background The population attributable fraction (PAF) that estimates potentially community-level effect of risk factors can be useful in planning public health interventions. This study compared different methods for calculating adjusted PAFs for cardiovascular diseases (CVD) in a cohort study with 10 years of follow-up. Methods Baseline data were employed from 6630 participants (3746 women) above 30 years old and 558 CVD events (238 women) detected during follow-up. Unadjusted approach using Levin9s formula, Miettinen formula approach using adjusted OR and HR estimated from logistic and Cox regression and direct estimation of average PAF from logistic regression using Ruckinger method, were applied. Result Estimated PAFs, using HR comparing OR, in both Levin9s and Miettinen9s formula, with tiny decrease, gave very similar results. However, according to the average PAF method, frankly, we reach to lower fractions; highest modifiable cardiovascular risk factor PAFs, in sequence, was hypertension (16.2%), smoking (14.8%), diabetes (10.1%), hypercholesterolaemia (8.5%) for men, and hypertension (25.6%), diabetes (18%), hypercholesterolaemia (10.7%), for women. Also PAF of Age ≥60 years and premature family history of CVD, as most important non-modifiable CVD risk factors, were 18.4%, 11.2% and 4.4%, 6.9% for men and women respectively. Conclusion If individual data (eg, cohort and case-control studies) are accessible then the direct estimation of average PAF provides more realistic results. Besides, it seems that the order of important risk factors is the same in men and women except smoking.

Introduction Attributable Fraction is the commonest method of describing the proportion of a health outcome attributable to an exposure in an exposed group. It applies to binary variables. Many variables are continuous; changing them to binary variables results in loss of information. Using traditional analyses we compared the importance of cardiovascular disease (CVD) risk factors in a continuous form. Methods A population based cohort study including 1802 men and 2301 women aged ≥40 years in Tehran. We considered modifiable continuous exposures at baseline and CVD events during 8.5 years of follow-up. Using factor analysis we extracted some uncorrelated and standardised factors, each related to a cluster of continuous variables with the same general feature (eg, systolic and diastolic blood pressure as blood pressure factors or body mass index and waist circumference as anthropometric factor); then, a Cox regression including these factors as scores was conducted to estimate the RR of the last quintile to the first for each factor. Finally we compared these similar RRs in the model using the Wald test. Results Anthropometric, blood glucose, blood pressure and cholesterol factors were extracted. The total variance explained by factors was 88.6% in men and 87.3% in women. In men all factors had the nearly the same RRs ranging from 1.7 to 2.2 but in women the RR of cholesterol was significantly higher than the others (3.4 vs 1.7–2.5). Conclusion To prevent CVD, all clusters of risk factors should be considered in control programs. Hypercholesterolaemia maybe more important in women.

Introduction Clinical usefulness of a risk function is a new concept that should be considered beyond the traditional checking of discrimination and calibration for performance of a model. Framingham risk score (FRS) for cardiovascular disease is a widely used one which has been validated in different countries but its clinical usefulness has been neglected. Methods We checked discrimination of FRS and so its calibration and clinical usefulness before and after recalibration in a population based cohort, Tehran lipid and glucose study, of 2640 men and 3584 women aged 30–74 years. To check clinical usefulness, we used decision curve analysis (DCA) and calculated net benefit of treatment for patients with ≥20% of 10 year probability of disease according to FRS model. Results The area under the curve for FRS model, was 0.794 and 0.838 for men and women respectively. The original model had a poor calibration but got a good one after recalibration (Hosmer-Lemeshow χ 2 statistic of 16.8 for men and 18.4 for women). Based on DCA, FRS was clinically useful in cut points of 10%–30%, as threshold probability of disease that a patient should be treated, before and after recalibration. The net benefit of model to treat patients at cut point of 20% did not differ significantly before and after recalibration in both men and women (p>0.3 based on bootstrap resampling). Conclusion Original FRS has a good discrimination and poor calibration in Iran but considering clinical usefulness, it can be used even without recalibration.

To examine, the predictors of incident chronic kidney disease (CKD) in a community-based cohort of Middle East population, during a mean follow-up of 9.9 years. In a sample of 3313 non-CKD Iranian adults ≥20 years the estimated glomerular filtration rate (eGFR) was calculated at baseline and at three year intervals during three consecutive phases. The eGFR 2% of individuals develops CKD each year. Our findings confirmed that sex- specific risk predictors should be considered in primary prevention for incident CKD.

Introduction Knowledge of the magnitude of attributable burden to cardiovascular disease (CVD) by diabetes, especially based on updated data are needed for health policy, priority setting and preventing CVD. This study aimed to estimate the contribution of diabetes to the attributable burden of cardiovascular disease in Iran. Methods WHO Comparative Risk Assessment (CRA) methodology was used to calculating Potential Impact Fraction (PIF). Data on the Prevalence of newly diagnosed diabetes mellitus (NDM) and known diabetes mellitus (KDM) were obtained from 3 rd Iranian surveillance of risk factors of non- communicable diseases and data on corresponding measures of effect were derived from a national- specific study with age and multivariate adjusted HRs. PIF were estimated on both theoretical minimum and feasible minimum risk. Uncertainty for the attributable burden was estimated by Monte Carlo simulation-modelling techniques incorporating sources of uncertainty. Results Based on multivariate- adjusted HRs, by reducing the per cent of Iranian women with diabetes from 10.05% to the feasible minimum risk level that is, 5%, 6.8% (95% uncertainty intervals: 3.5 to 9.8) of attributable Disability Adjusted Life Years (DALYs) to CVD are avoidable and the corresponding value for men were 3.1% (95% uncertainty intervals: 1.4 to 4.8). Conclusion Although data on the Prevalence of diabetes and corresponding measures of effect were obtained from an updated and country- specific source, but to better priority setting, PIF should be applied to updated and revised burden of CVD.

Introduction Elevated blood pressure may lead to incident diabetes. Yet, data about the effect of different blood pressure components on incident diabetes in Middle Eastern women is lacking. Methods we evaluated systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP) and mean arterial pressure (MAP) as independent predictors of diabetes in Iranian women. We performed a population-based prospective study among 3028 non-diabetic women, aged ≥20 years. ORs of diabetes were calculated for every 1 SD increase in SBP, DBP, PP and MAP. Results During ≈6 years of follow-up, 220 women developed diabetes. There were significant interactions between family history of diabetes and SBP, PP and MAP (p≤0.01) in predicting incident diabetes. In women without a family history of diabetes, all blood pressure components were significantly associated with diabetes in the age adjusted model; the risk-factor-adjusted ORs were significant (p Conclusion In women without family history of diabetes, SBP, PP and MAP, were independent predictors of diabetes with almost similar predictive ability; hence in the evaluation of the risk of blood pressure components for prediction of diabetes, the presence of family history of diabetes should be considered.

Background: In Nov 2013, the instruction for controlling high cholesterol has been released by the American College of Cardiology (ACC) and the American Heart Association (AHA) which need to be assessed in the different communities. Methods: Of total 6275 individual aged 40-75 years who entered at the Tehran Lipids and Glucose Study from March 1999 to 20 March 2010 in first examination cycle, 5153 with the median follow-up of more than ten years were eligible to enter in this study. The 10-year risk of hard cardiovascular disease (Hard CVD) for Statin therapy based on ACC/AHA clinical guideline was calculated and this risk was calculated for each subgroup of the guideline who recommended for statin therapy comparing to the risk in individuals with prevalent CVD. Results: Of nearly 6.5 million urban population of Iran (according to the 1996 census) about 4 million individuals (2.55 million men and 1.4 million women) were eligible for statin therapy. With respect to the urban population growth from the 1996 to the 2011 census (about 2.5 percent increases) the number of individuals for receiving statin increased by 50% (5 million men and 3 million women). Also, the risk in non-diabetic men with calculated risk of 5-7.5% and diabetic women with calculated risk of

In epidemiologic studies, the measurement of characteristics of interest is almost always subject to random measurement error. This error and its effects are usually overlooked by researchers. One of its effects is a widespread statistical phenomenon that is well known as regression to the mean. This phenomenon occurs whenever an extreme group of people is selected from a population based on their measurements of a variable. If a second measurement is taken in this group, the mean of the second measurement will be closer to the mean of the population. In interventional studies, this increase (decrease) might be regarded as the effect of intervention, when in fact it has had no effect. Ignoring regression to the mean will lead to the erroneous conclusions and interpretation of the results of epidemiologic studies and affects the decisions in evidence-based medicine and planning for preventive and public health measures. This paper highlights the importance of this problem and its effects in epidemiologic studies and the ways to avoid it.

Un-weighted and weighted OR (95% CI) of diabetes mellitus according to white rice intake in the Golestan Cohort Study (GCS), (2004â 2007)* (DOCX 19 kb)

Background & Objectives: Cardiovascular disease is the first cause of death and third place in disease burden in Iran. This study estimates population attributable fraction (PAF) of cardiovascular risk factors in Tehran population. PAF is one of the important parameters of measuring population affect of risk factors and evaluating potential impact of preventive strategies in community level. Methods: In this study 5868 participants above 30 years old of Tehran lipid and glucose study (TLGS) were employed and 501 CVD events detected during 10 years follow-up. Direct estimate of adjusted PAFs using logistic regression which is one of less biased exist methods of PAF calculation were applied. Results: Highest modifiable cardiovascular risk factor PAFs, in sequence, was smoking (14.16%), hypertension (11.73%), diabetes (7.32%), hypercholesterolemia (6.85%) and central obesity (5.91%) for men, and hypertension (19.25%), diabetes (18.82%), central obesity(9.88%) and hypercholesterolemia (7.95%), for women. Also PAF of hazardous age and premature family history of CVD, as most important nonmodifiable CVD risk factors, were 36.09%, 16.61% and 3.95%, 7.56% for men and women respectively. Conclusion: According to the difference of risk factors PAFs ranking in men and women, it is suitable that CVD preventive interventions to be prioritized by sex separately. In this regard, besides special attention to control tobacco use in men, hypertension and diabetes in both sexes and high cholesterol in men and central obesity in women respectively, should be given in priority of preventive strategies.

Table S1. Distribution of individuals in Golestan Cohort Study (GCS) and Tehran Lipid and Glucose Study (TLGS) meeting fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), oral glucose tolerance test (OGTT) and diabetes medications criterion for Type 2 Diabetes Mellitus Definition. (DOCX 46 kb)

Background & Objectives: The case-cohort study is one of the youngest designs in epidemiology and some methodological aspects of it are still in debate. This study aimed at comparing the estimated hazard ratio, standard error, and interaction hazard ratio between the case-cohort and cohort studies for assessing the relationship between diabetes and cardiovascular diseases.Methods: A total of 1701 men and 2253 women aged between 40 and 75 years were considered as the main cohort. Subcohort sampling was performed using simple random sampling with a sampling fraction of 0.3%. The hazard ratio of the cohort study was calculated using Cox regression model and the 3 methods of Prentice, Self-Prentice, and Barlow were used for calculating the hazard ratio of the case-cohort study. The mentioned regression models were used to assess the interactions.Results: The results of the two studies were similar in populations with higher incidence (cohort of men) and lower incidence (the cohort of women) when frequency percent of exposure variable was greater than 10%. When the sample size of the initial cohort was less than 1250 subjects, discrepancies were observed between the results of the two studies. In addition, the standard error of the case-cohort study was higher than the cohort study. The results of both studies were similar in assessing the considered interactions.Conclusion: The results are similar when the initial cohort sample sizes are sufficient. Meanwhile, unlike the percentage of exposure frequency, the outcome incidence has a negligible impact on the discrepancy between the results while the effect of the relative frequency of the exposure levels on the results discrepancy is noticeable.

Background & Objectives: Some studies on chronic diseases have indicated that obesity may result in a paradoxically longer survival. The present study was aimed to investigate the effect of Chronic Kidney Diseases (CKD) and Metabolic Syndrome (MetS) on the incidence of Coronary Heart Disease (CHD). Methods: In order to record time to CHD events, a sample of 6,507 individuals (mean age 47.4 years, 43.4% males) was followed for nearly 10 years. Participants were also categorized into four groups according to presence/absence of CKD and MetS. Then, using a Multivariate Cox Regression, the Hazard Ratio (HR) of each group was estimated relative to individuals free of both CKD and MetS separately for obese (BMI&ge27.1 Kg/m2) and non-obese persons (BMI

Table S2. OR (95% CI) of diabetes mellitus according to white rice intake by age categories, sex, physical activity, race/ethnicity and residence intake in Tehran Lipid and Glucose Study (TLGS), (2004â 2006). (DOCX 72 kb)

Table S1. Distribution of individuals in Golestan Cohort Study (GCS) and Tehran Lipid and Glucose Study (TLGS) meeting fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), oral glucose tolerance test (OGTT) and diabetes medications criterion for Type 2 Diabetes Mellitus Definition. (DOCX 46 kb)

Un-weighted and weighted OR (95% CI) of diabetes mellitus according to white rice intake in the Golestan Cohort Study (GCS), (2004â 2007)* (DOCX 19 kb)