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Objective. Limited data are available regarding prognostic value of nitric oxide metabolites (NOx) for clinical hard end points. In this study, we defined optimum cut-off values of serum NOx for predicting all-cause and cardiovascular disease (CVD) mortality events and prospectively investigated their hazards in the presence of traditional risk factors. Design. Serum NOx concentrations were measured at baseline (2006-2008) and 3520 adult men and women were followed during 7.7 years for all-cause and cardiovascular disease (CVD) mortality. To determine the optimal cut-off points of serum NOx, the receiver operator characteristic (ROC) curve analysis was used. Multivariate Cox proportional hazard models were used to estimate the hazard ratios (HRs) with 95% confidence intervals (95% CIs) of all-cause and CVD mortality below and above the defined optimal cut-off points of serum NOx. Results. Mean age of participants was 44.5 ± 16.0 years at baseline and 40.2% were male. Median (inter-quartile range) of serum NOx levels was 25.0 µmol/L (19.0-37.0), at baseline. The optimal cut-off points of serum NOx levels for predicting CVD and all-cause mortality were 30.5 and 32.5 µmol/L, respectively. In the presence of age, sex, body mass index, smoking, type 2 diabetes, hypertension, and history of CVD, a significant increased risk of CVD mortality (HR = 1.98, 95% CI = 1.10-3.58) and all-cause mortality (HR = 1.52, 95% CI = 1.05-2.21) was observed for serum NOx values higher than their cut-offs. Conclusion. Serum NOx level may be predictor of CVD mortality and death, in general populations. [ABSTRACT FROM AUTHOR]

Aim: This study was conducted to investigate whether serum NO metabolites (NOx) could predict the occurrence of type 2 diabetes (T2DM), hypertension (HTN) and metabolic syndrome (MetS). Methods: We measured serum NOx concentrations in the Tehran Lipid and Glucose Study participants (aged ≥19 years) and followed them for a median of 7.7 years for the incidence of outcomes. To determine the appropriate cut-off points of serum NOx for predicting clinical events, a random sampling method (50:50 ratio) was used for the population and for analysis, receiver operator characteristic curve was used. Multivariable Cox proportional hazard models were used to estimate the hazard ratios (HRs) with 95% confidence intervals (95% CIs) of T2DM, HTN and MetS in response to serum NOx values. Results: The optimal cut-off points of serum NOx levels for predicting T2DM, HTN and MetS were 26.5, 25.5 and 25.5 µmol/L, respectively. Participants with serum NOx levels ≥25.5 µmol/L had increased risk of MetS (HR = 1.31, 95% CI = 1.01–1.72). No evidence was found for any association of serum NOx with incidence of T2DM and HTN (HR = 1.03, 95% CI = 0.83–1.77 and HR = 1.09, 95% CI = 0.88–1.35). Conclusion: In this prospective population-based investigation, a higher circulating NOx was associated with development of MetS. [ABSTRACT FROM AUTHOR]

Emerging data suggest that impaired nitric oxide (NO) homeostasis has a key role in development of cardiometabolic disorders. The association between circulating levels of NO metabolites, i.e. nitrate and nitrite (NOx), and risk of chronic diseases has not yet been fully clarified. This work aims to address epidemiologic aspects of NO metabolism and discusses different physiologic and pathophysiologic conditions influencing circulating NOx. Further, cross-sectional associations of serum NOx with metabolic disorders are described and along the way, potential short-term and long-term power of serum NOx for predicting cardiometabolic outcomes are reviewed. Results from population-based studies show that circulating NOx is affected by aging, smoking habits, pregnancy, menopause status, thyroid hormones, and various pathologic conditions including type 2 diabetes, insulin resistance, hypertension, and renal dysfunction. Lifestyle factors, especially dietary habits, but also smoking habits and the degree of physical activity influence NO homeostasis and the circulating levels of NOx. Elevated serum NOx, due to increased iNOS activity, is associated with increased incidence of metabolic syndrome, different obesity phenotypes, and cardiovascular events. [ABSTRACT FROM AUTHOR]

Objective: There is an interaction between dietary sodium/potassium intake in the pathogenesis of hypertension (HTN) and cardiovascular disease (CVD). The aim of this study was to investigate the association of dietary sodium to potassium (Na/K) ratio and the risk of HTN and CVD in a general population of Iranian adults. Methods: In this prospective cohort study, adults men and women with complete baseline data were selected from among participants of the Tehran Lipid and Glucose Study and were followed up for 6.3 years for incidence of HTN and CVD outcomes. Dietary sodium and potassium were assessed using a valid and reliable 168-item food frequency questionnaire. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between dietary sodium, potassium and their ratio and risk of outcomes. Results: During the study follow-up, 291 (15.1%) and 79 (5.0%) new cases of HTN and CVD were identified, respectively. No significant association was observed between usual intakes of sodium, potassium and dietary Na/K ratio with the incidence of HTN. There was no significant association between dietary intakes of sodium and potassium per se and the risk of CVD, whereas when dietary sodium to potassium ratio was considered as exposure in the fully-adjusted Cox regression model, and participants in the highest compared to lowest tertile had a significantly increased risk of CVD (HR = 2.19, 95% CI = 1.16-4.14). Conclusions: Our findings suggest that high dietary Na/K ratio could contribute to increased risk of CVD events. [ABSTRACT FROM AUTHOR]

Background: There is growing evidence regarding the potential properties of nitrate-rich foods in development of chronic diseases. In this study, we investigated the association of nitrate-containing vegetables (NCVs) and the risk of chronic kidney disease (CKD).Methods: We evaluated 1546 eligible adult participants of the Tehran Lipid and Glucose Study (TLGS), at baseline (2006–2008) and again after 3 years (2009–2011). Dietary intake was collected using the validated semi-quantitative food frequency questionnaire. Nitrate-containing vegetables and its categories including high-, medium-, and low-nitrate vegetables were defined. Estimated glomerular filtration rate (eGFR) and CKD were defined. Association between NCVs and CKD in the cross-sectional phase and the predictability of NCVs consumption in CKD occurrence were assessed using multivariable logistic regression models with adjustment for potential confounders.Results: Mean dietary intake of energy-adjusted NCVs was 298.0 ± 177.3 g/day. Highest compared to the lowest tertile of NCVs was accompanied with a significantly lower mean eGFR (76.6 vs. 83.3, mL/min/1.73 m2,p < 0.001) and a higher prevalence of CKD (21.7 vs. 9.9%,p < 0.001). At baseline, higher intake of high-NCVs was associated with a 48% higher chance of having CKD (OR = 1.48, 95% CI = 1.05–2.13). After 3 years of follow-up, there was no significant association between consumption of total NCVs and its categories with the occurrence of CKD.Conclusion: Considering the lack of association between high-NCVs intakes and the risk of CKD in prospective analysis, additional research is recommended to clarify possible effect of nitrate intakes from vegetables on kidney function. [ABSTRACT FROM PUBLISHER]

Background and aimThis study was conducted to investigate the association between serum nitric oxide metabolites (NOx) and the risk of chronic kidney disease (CKD).MethodsWe recruited 3462 and 2504 participants of the Tehran Lipid and Glucose Study (TLGS), for a cross-sectional and prospective analysis, respectively. Serum NOx concentrations were measured at baseline (2006–2008), and demographics, anthropometrics and biochemical variables were evaluated at baseline and again after 3 years (2009–2011). Estimated glomerular filtration rate (eGFR) and CKD were defined. Association between serum NOx and CKD in the cross-sectional phase and the predictability of NOx in CKD occurrence were assessed using multivariable logistic regression models with adjustment for confounders.ResultsMean age of participants was 45.0 ± 15.9 years at baseline and 40.5% were male. The prevalence of CKD was 17.9% (13.4% in men, 21.0% in women) at baseline, at which point, marginally significant odds of CKD in the highest tertile of serum NOx in men (OR = 1.53, 95% CI = 0.96–2.45,pfor trend = 0.047) and a significant odds of CKD in women (OR = 2.48, 95% CI = 1.76–3.49,pfor trend = 0.001) were observed. After a 3-year follow-up, in women, risk of CKD was higher in the highest compared to the lowest NOx tertiles (OR = 1.86, 95% CI = 1.10–3.14,pfor trend = 0.032) but no significant association was observed in men.ConclusionSerum NOx level was found to be an independent predictor of CKD in women; it could be a valuable surrogate for prediction of renal dysfunction in women and help to identify high-risk subjects. [ABSTRACT FROM PUBLISHER]

Background: In this study, we aimed to investigate the association of dietary phytochemical index (DPI) with insulin resistance, β-cell dysfunction, and insulin sensitivity.Methods: This longitudinal study was conducted on 1141 participants of the Tehran Lipid and Glucose Study. Dietary data were collected using a validated semi-quantitative FFQ with 168 food items at baseline and DPI was calculated. Fasting serum insulin and glucose were measured at baseline and again after a 3-year of follow-up.Results: After 3-years of follow-up, the risk of hyperinsulinemia significantly decreased by 65 (OR = 0.35, 95% CI = 0.21-0.60) and 86% (OR = 0.14, 0.07-0.29), in the third and fourth quartile categories of DPI, respectively. The occurrence of insulin resistance and insulin insensitivity in participants with higher DPI was significantly lower than the others (OR = 0.48, 95% CI = 0.25-0.93 and OR = 0.11, 95% CI = 0.05-0.24, respectively).Conclusion: Higher consumption of phytochemical-rich foods may have protective effects against development of insulin resistance. [ABSTRACT FROM AUTHOR]

Current epidemiologic data lack consistent evidence for an association between consumption of dairy products and breast cancer risk. In this study we assessed the relationship between consumption of dairy products and the odds of breast cancer. This case-control study was conducted on 275 women (100 cases and 175 controls). Data regarding sociodemographic factors, medical history, medications, and anthropometric measurements were collected. Dietary data were assessed using a validated food frequency questionnaire. The odds [95% confidence interval (CI)] of breast cancer were estimated across quartile categories of energy-adjusted dairy intake using multiple logistic regression models with adjustment for confounders. We observed that higher consumption of total dairy intake was accompanied with reduced breast cancer risk [odds ratio (OR) = 0.14, 95% CI = 0.04–0.38]. A similar inverse association was also observed for higher intakes of low-fat and fermented dairy products (Pfor trend <0.05). Lower intake of high-fat dairy was associated with reduced odds of breast cancer, and no significant association was found between nonfermented dairy and breast cancer risk. Our study demonstrates the protective effects of high intakes of total dairy, low-fat and fermented dairy, as well as low intakes of high-fat dairy products against breast cancer risk and shows no association with nonfermented dairy. [ABSTRACT FROM PUBLISHER]

Use of antioxidant components is a new approach for improvement of insulin resistance (IR) as a main feature of type 2 diabetes and its complications. The aim of this study was to investigate the effects of broccoli sprouts powder (BSP) containing high concentration of sulphoraphane on IR in type 2 diabetic patients. Eighty-one patients were randomly assigned to receive 10 g/d BSP (A, n = 27), 5 g/d BSP (B, n = 29) and placebo (C, n = 25) for 4 weeks. Fasting serum glucose and insulin concentration, glucose to insulin ratio and homoeostasis model assessment of IR (HOMA-IR) index were measured at baseline and again 4 weeks after treatment. Seventy-two patients completed the study and 63 were included in the analysis. After 4 weeks, consumption of 10 g/d BSP resulted in a significant decrease in serum insulin concentration and HOMA-IR ( p = 0.05 for treatment effect). Therefore, broccoli sprouts may improve IR in type 2 diabetic patients. [ABSTRACT FROM AUTHOR]