Tehran Lipid And Glucose Study Research Articles

Association between body mass index trajectories and type 2 diabetes incidence over an 18-year follow-up in the Tehran Lipid and Glucose Study.

Body mass index (BMI) is a well-known risk factor for type 2 diabetes mellitus (T2DM). We aimed to identify BMI trajectory patterns and evaluate their association with T2DM during 18 years of follow-up. We included 6026 participants aged 20 to 65 from the prospective population-based Tehran Lipid and Glucose Study (TLGS). The BMI trajectory patterns were identified using latent growth mixture modeling (LGMM) during the measurement period. The association between the BMI trajectory patterns and future T2DM was evaluated using the Cox proportional hazard regression models. Three BMI trajectory patterns of low-increasing (38.6%), medium-increasing (47.1%), and high-increasing (14.3%) were detected. The participants in the medium-increasing and high-increasing BMI trajectory groups had HRs of 1.87 (95% CI 1.53-2.28) and 3.41(95% CI 2.71-4.29) for T2DM incidence, respectively. Within the normoglycemic subpopulation, the high-increasing BMI group had an HR of 3.82 (95% CI 2.79-5.24) compared to the low-increasing BMI group, while in the prediabetic subpopulation, the high-increasing BMI group had an HR of 2.93 (95% CI 2.04-4.19) compared to the low-increasing BMI group. Body weight varies in a relatively stable pattern in adulthood over the long-term period. Medium and high-increasing BMI trajectory patterns have a significantly increased risk for future T2DM in both normoglycemic and prediabetic individuals. Identifying BMI trajectory patterns can help healthcare providers in early prediction, risk assessment, and monitoring strategies development for the prevention of T2DM.

Association between urinary sodium-to-potassium ratio, elevated blood pressure phenotypes and microalbuminuria: Tehran Lipid and Glucose Study.

This cross-sectional study investigated the associations between urinary sodium (UNa) to potassium (UK) ratio, different phenotypes of elevated blood pressure (BP), and microalbuminuria (MAU) in a cohort of the Tehran Lipid and Glucose Study (TLGS). Adult participants (n = 1782, mean age of 43.0 ± 13.7 years and 46.0% were men) were recruited (2015-2017) for measurements of spot urinary metabolites, i.e., Na, K, creatinine (Cr), microalbumin, and BP. Multinomial logistic regression was used to estimate the relative risk ratios (RRR) of elevated BP phenotypes [i.e., isolated systolic (ISH), diastolic (IDH), and systolic-diastolic (SDH) hypertension], and binary logistic regression was used to estimate odds ratios (ORs) of MAU across quintile categories and per each SD-increment of UNa-K ratio. Mean UNa, UK, and its ratio was 137 ± 57.4, 72.1 ± 36.6 mmol/L, and 2.31 ± 1.41, respectively. Subjects with UNa-K > 3.14 had higher prevalence of ISH (3.4 vs. 1.1%), SDH (11.0 vs. 6.2%), and MAU (14.1 vs. 6.2%) (P for all < 0.05). Highest compared to the lowest UNa-K ratio values (> 3.14 vs. <1.23) was associated with an increased probability of SDH (RRR = 1.79, 95% CI 1.09-3.19) and MAU (OR = 2.53, 95% CI 1.23-5.20). Every 1 SD-increment of the UNa-K ratio was associated with a 29 and 38% increased chance of having SDH and MAU, respectively. Our findings imply that a high UNa-K ratio may be a potential risk factor for elevated BP and renal dysfunction.

Health-related quality of life in adults with metabolic syndrome: a multi-level analysis of family and individual level variation

Purpose The current study aimed to investigate the associations between metabolic syndrome (MetS) with health-related quality of life (HRQoL) using multilevel analysis among the Iranian adult population. Methods This cross-sectional study was conducted in the framework of the Tehran Lipid and Glucose Study (TLGS). Participants were 6113 participants (3318 women and 2795 men) aged≥20 years of the TLGS seventh phase who had completed data on HRQoL and MetS. HRQoL was assessed using the short-form 12-item health survey V.2 and MetS defined based on the guidelines outlined in the Joint Interim Statement. The two-level model was fitted to assess the association between MetS and HRQoL. Results The prevalence of MetS and its components was higher in men, and regardless of metabolic status, men exhibited higher HRQoL values. The deleterious impact of MetS on HRQoL was more pronounced in women, while the detrimental effects of MetS on men’s HRQoL were confined to specific subscales. These results were obtained through multilevel analysis, considering both familial and individual variation levels. Moreover, our investigation highlighted the positive influence of leisure-time physical activity on both the physical and mental component summaries (PCS and MCS, respectively), regardless of gender. Education had a greater positive impact on PCS in both sexes. Additionally, a history of cardiovascular diseases was associated with a decline in mental and physical HRQoL, while age was linked to a decline in PCS and MCS, and smoking was associated with a decline in MCS. Conclusion This study revealed the significant influence of gender, as well as the unique characteristics and circumstances of individuals, on the relationship between MetS and HRQoL in a general population with low/middle income.

The trend of correlation changes of macronutrient intakes among different familial pairs: a prospective study among participants of Tehran Lipid and Glucose Study

Background/AimFamilial resemblance in dietary patterns has been a subject of interest, with both genetic and environmental factors playing crucial roles. This study aims to investigate trends in macronutrient intake correlations over a 9-year period among different familial pairs, including parent-offspring, siblings, and spouses, using data from the Tehran Lipid and Glucose Study (TLGS).MethodsThis longitudinal study, conducted within the framework of the TLGS, analyzed data from 1,814 families over a 9-year period. Dietary intakes were assessed using a validated 168-item food frequency questionnaire. Macronutrient intakes were calculated and adjusted for age. Familial correlations were estimated using intraclass correlation coefficients for various familial pairs (parent-offspring, siblings, and spouses) across four consecutive surveys. Changes in correlations were analyzed over 3-year, 6-year, and 9-year intervals, as well as across all four surveys, to determine overall trends in macronutrient intake correlations.ResultsThe results revealed diverse trends in intake correlations for carbohydrates, proteins, fats, and specific fatty acids across familial relationships. Parent-offspring dyads exhibited varied patterns, with some nutrients showing regression to the mean. Sister-sister pairs demonstrated strengthening correlations for energy, carbohydrates, fats, and saturated fatty acids over time. Conversely, brother-sister pairs displayed weakening correlations for most macronutrients, particularly energy, proteins, cholesterol, and fiber. Spouse correlations tended towards regression to the mean for energy, carbohydrates, and fats, and fiber.ConclusionsThe present study illuminates the dynamic nature of familial dietary correlations over time. The contrasting trends between sister-sister and brother-sister dyads suggest a significant influence of gender on shared dietary patterns. These findings underscore the complex interplay of genetic and environmental factors in shaping family dietary behaviors and highlight the importance of considering both gender and relationship type when examining familial nutritional habits.

Trend analysis, gender-specific patterns, and age dynamics of childhood and adolescent obesity: insights from the Tehran lipid and glucose study

BackgroundChildhood and adolescent obesity pose significant challenges to global health, with escalating prevalence and associated short- and long-term health consequences. This longitudinal study leveraged data from the Tehran Lipid and Glucose Study (TLGS) to investigate the trends of obesity among Tehranian children and adolescents over a 21-year period.MethodsUtilizing data from TLGS phases I to VII (1999–2021), we included 3845 participants aged 3–18 years at the beginning of phase I. Anthropometric measures, including height and weight, were collected, and body mass index (BMI) was calculated. Childhood obesity (2–19 years) was defined as BMI-for-age > 2SD based on World Health Organization (WHO) standards, and adult obesity was defined as BMI ≥ 30. Descriptive statistics, trend analysis, prevalence calculations, odds ratios, and interaction analyses were employed for data interpretation.ResultsThe mean BMI increased from 18.46 ± 4.37 kg/m² at Phase I to 26.36 ± 5.03 kg/m² at Phase VII. Boys exhibited a greater increase in BMI than girls, and age at study entry influenced BMI trajectories. The prevalence of obesity rose from 6.4% at Phase I to 21.5% at Phase VII, with a more pronounced increase in boys. Odds ratios for obesity steadily increased across phases, indicating a growing risk. Interaction analyses revealed age-specific dynamics, with older participants demonstrating lower odds ratios initially but higher odds ratios in later phases.ConclusionOur study shows a worrisome increase in childhood obesity among Tehranian children and adolescents over 21 years. Sex- and age-specific trends emphasize the necessity for targeted interventions, informing policymakers, healthcare practitioners, and educators regarding public health strategies and interventions against the obesity epidemic.

Ultra-processed foods and the incidence of pre-diabetes and type 2 diabetes among Iranian adults: the Tehran lipid and glucose study

BackgroundNo study has investigated the association between ultra-processed food (UPF) and pre-diabetes development. Furthermore, prior investigations on the association between UPF and the risk of type 2 diabetes (T2D) were primarily conducted in Europe and America, and studies in other regions are lacking. We investigated the association between ultra-processed foods and the risk of pre-diabetes and T2D in a cohort of Iranians.MethodsThis prospective study, with a sample size of 1954 for pre-diabetes and 2457 for T2D, was conducted among adults’ participants (aged ≥ 18 years) from the Tehran Lipid and Glucose Study (TLGS). We defined UPF intake using NOVA calcification as a proportion of total energy, and calculated its average intake during the follow-ups. The hazard ratios (HR) and 95% confidence intervals (95% CI) for pre-diabetes/T2D across tertiles of total UPF and per 10% of its increment were examined using Cox proportional hazards models. We also investigated the possibility of non-linear association using a restricted cubic spline regression.ResultsWe identified 766 and 256 cases of pre-diabetes and T2D, respectively, during a median follow-up of 7 years for pre-diabetes and 8.6 years for T2D. In the multivariable adjusted model, a 10% increase in total UPF intake was associated with a 12% higher risk of pre-diabetes (HR = 1.12; 95% 1.02, 1.23). The incidence of pre-diabetes was also higher in those in tertile 3 than those in tertile 1 (HR = 1.28; 95% CI = 1.07, 1.52). Following additional adjustment for diet quality, the results remained unchanged. Spline regression demonstrated a J-shaped association between UPF and the risk of pre-diabetes; the risk of pre-diabetes did not increase until UPF consumption exceeded about 24% of total energy intake. Of the individual UPF, hydrogenated fat/mayonnaise/ margarine group was related to an increased risk of pre-diabetes. The total UPF and its individual items were not associated with T2D.ConclusionsThis study found a positive, non-linear relationship between total UPF and the risk of pre-diabetes in Iranian adults. Our data could not show any significant association between UPF and T2D risk.

Consumption of ultra-processed foods and the incidence of hypertension: a cohort study.

The incidence of hypertension (HTN) and consumption of ultra-processed foods are increasing worldwide. However, only a limited amount of research has assessed the causality between ultra-processed foods and the risk of HTN. Therefore, the present study aimed to determine the association between ultra-processed foods and the risk of HTN in a prospective cohort study. In the present study, we included 2399 individuals, aged approximately 19 years, who participated in the Tehran Lipid and Glucose Study (TLGS). The participants had complete dietary data and were free from HTN at baseline. We used the Cox proportional hazards model to determine the association between ultra-processed food intake and the risk of HTN occurrence, reporting the results as the hazard ratio (HR) and 95% confidence interval (95% CI). The mean age of participants was 37.6 years, and we followed them up for an average of 9.21 years. Our results indicated that participants in the highest tertile of ultra-processed foods had a 48% higher risk of HTN development (HR: 1.48; 95% CI: 1.23, 1.79) than those in the lowest tertile. We found a significant association between age and ultra-processed food intake in relation to the risk of HTN. The HR for developing HTN in participants aged <47 years was 1.99 (95% CI: 1.53, 2.58) and in participants aged ≥47 years was 1.26 (95% CI: 0.95, 1.68). Among the ultra-processed food components, consumption of industrial fat products had a positive correlation with the risk of HTN (HR: 1.04; 95% CI: 1.02 to 1.06). Our results suggest that consuming ultra-processed foods is associated with an increased incidence of HTN in adults. This association varied by age and was significant for adults younger than 47 years.

Comparative analysis of adolescent hypertension definitions for predicting early-adulthood carotid artery intima-media thickness: Tehran lipid and glucose study.

Definitions of childhood and adolescent hypertension (HTN) do not precisely elucidate the relationship between HTN and cardiovascular outcomes. Carotid intima-media thickness (CIMT), as a substitute for cardiovascular outcomes, enables the early identification of cardiovascular events throughout early adulthood. This study aimed to compare the ability of childhood HTN definitions to predict a high CIMT in early adulthood. This prospective cohort study included 921 individuals aged 10-17 years from the Tehran Lipid and Glucose Study (TLGS). The CIMT was measured after 18 years of follow-up. Participants were categorized into normal blood pressure (BP), high-normal BP, HTN stage 1, and HTN stage 2 groups based on the childhood HTN definitions of the 4th report, European Society of Hypertension (ESH), and American Academy of Pediatrics Clinical Practice Guidelines (AAP-CPG). Akaike's information criterion (AIC) and relative efficiencies (RE) were calculated to compare the ability of each to predict a high CIMT (≥95th percentile) during early adulthood. The highest and lowest prevalence of stage 1 HTN was observed with the AAP-CPG (17.7%) and ESH (8.8%), respectively. Similarly, the highest and lowest prevalence of stage 2 HTN was noted with the AAP-CPG (1.5%) and ESH (0.8%), respectively. According to the RE values, the highest to lowest predictive abilities belonged to the 4th report, ESH, and AAP-CPG, respectively. In all models, the 4th report's pediatric HTN definition had the lowest AIC value and offered the best predictive ability. Among the various definitions of pediatric HTN, the 4th report offered the best ability to predict a high CIMT during early adulthood, followed by the ESH and AAP-CPG. Because the reference population of the 4th report includes overweight, obese, and normal-weight individuals, our findings suggest that excessive adiposity is among the main predictors of early adulthood atherosclerosis risk.

The association of body weight change and regression to normoglycemia in different phenotypes of pre-diabetes: Findings of a longitudinal cohort study

AimWe investigated the association of 3-year change in body weight (BW) and regression to normal glucose regulation (NGR) among different phenotypes of pre-diabetes (Pre-DM), i.e., isolated impaired glucose tolerance (iIFG), isolated impaired fasting glucose (iIGT) and combined IFG-IGT. Research Design and Methods1458 Pre-DM subjects (iIFG=618, iIGT=462, and IFG-IGT=378) were assessed for 3-year change-percent in BW (2006-2008 to 2009-2011) and then followed up to 2015-2017, within the national cohort of Tehran Lipid and Glucose Study (TLGS). Binary logistic regression models were used to estimate the probability (odds ratio, ORs) of regression to NGR across categories of 3-year BW change (i.e., ≥5% BW loss, 0-5% BW loss, BW gain) in different phenotypes of Pre-DM. ResultsThe mean age of the participants was 53.0±13.7, and 46.8% were men. Over a median of 6 years of follow-up, the rate of regression to normoglycemia was 50.6, 43.2, and 12.7% in iIGT, iIFG, and combined IFG-IGT, respectively. The baseline-adjusted mean of 3-year BW change was not significantly different across Pre-DM phenotypes (0.68±0.19, 0.32±0.22 and 0.23±0.24 kg, in iIFG, IGT, and IFG-IGT). Three-year BW loss ≥5% was associated with a greater NGR probability in iIGT than other phenotypes (OR=4.29 vs. 3.90 and 2.84 in IFG-IGT and iIFG, respectively). A modest reduction (0-5% of initial BW) resulted in an increased chance of Pre-DM regression among subjects with IGT (OR=1.61, 95% CI=1.03-2.52) but not iIFG or IFG-IGT phenotypes. ConclusionShort-term intensive BW loss (≥5% of initial BW) increased NGR probability in all Pre-DM phenotypes, with an order of iIGT>combined IFG-IGT>iIFG. Only iIGT take advantage of moderate BW loss (0-5% of initial BW) for increasing chance of Pre-DM regression.

Fruit and vegetable intake modifies the association between ultra-processed food and metabolic syndrome

BackgroundThis prospective cohort study aimed to investigate the association between ultra-processed food (UPF) and the risk of metabolic syndrome (MetS), as well as to assess whether fruit and vegetable intake and weight change modify this association.MethodsWe included 1915 healthy participants who participated in the Tehran Lipid and Glucose Study (TLGS), all of whom had complete demographic, anthropometric, and dietary measurements. A validated food frequency questionnaire was used to assess UPF consumption based on the NOVA classification system. MetS was defined according to the Joint Interim Statement. Multivariable adjusted Cox regression was used to estimate hazard ratios (HRs) for MetS events across tertiles of UPF. The effect of fruit and vegetable consumption and weight change on this association was assessed using joint classification by Cox regression.ResultsUFP consumption showed no association with MetS risk after adjusting for confounders. However, after adjustment for dietary fiber, fruits, and vegetables, the highest tertile of UPF consumption was positively linked to MetS risk, compared to the lowest tertile. There was a significant interaction between fruit, vegetable, and dietary fiber intake and UPF consumption concerning the risk of MetS (All P values < 0.05). Among individuals consuming less than 248 g/day of fruit, the risk of MetS increased by 54% (confidence interval: 1.13–2.10) in the highest UPF tertile. Consuming vegetables and dietary fiber below the median (258 g/day and 42.2 g/day, respectively) increased the risk of MetS in the third tertile of UPF. However, consuming vegetables and fiber ≥ median intake, reduced the risk of MetS among those with the lowest UPF consumption. Furthermore, the risk of MetS was observed in the third tertile of UPF consumption among individuals with fruit and vegetable consumption < 537 g/day. UPF consumption was not associated with the risk of MetS in different weight change statuses.ConclusionsConsuming more fruits and vegetables mitigated the adverse effect of UPF on the risk of developing MetS.

Correction: Bibliometric overview of the Tehran lipid and glucose study (TLGS) publications from 2000 to 2022

Correction: Bibliometric overview of the Tehran lipid and glucose study (TLGS) publications from 2000 to 2022

Cardiometabolic Profile in Young Adults With Diverse Cigarette Smoking Histories: A Longitudinal Study From Adolescence.

For the first time, the present study investigated smoking trajectory and cardiometabolic profile from adolescence to young adulthood in a middle-income developing country facing a high prevalence of smoking and cardiovascular disease-related outcomes. Data on 1082 adolescents (12-18 years of age) who participated in the TLGS (Tehran Lipid and Glucose Study) were gathered,and participants were followed for a median of 12.5 years (baseline: 1999-2002, last follow-up: 2014-2017). Participants were categorized as non/rare smokers, experimenters, and escalators using group-based trajectory models. Statistical analysis was used to compare the trajectory groups' cardiometabolic components, clinical characteristics, and cardiometabolic changes due to the individuals' placement in experimenter and escalator groups compared with non/rare smokers. The smoking trajectory groups in young adulthood differ significantly in blood pressure, triglycerides, high-density lipoprotein cholesterol, waist circumference, and body mass index, with the escalator group having the highest risk values for each component. Significant differences were observed in blood pressure (P=0.014), triglycerides (P<0.001), and waist circumference (P<0.001) status after using clinical cut points. The adjusted linear regression revealed that the escalator group had 3.16 mm Hg-lower systolic blood pressure SBP (P=0.016), 2.69 mm Hg-lower diastolic blood pressure (P=0.011), and 4.42 mg/dL-lower high-density lipoprotein cholesterol (P=0.002), compared with the non/rare smoker group. Despite elevated risks in unadjusted analyses for all cardiometabolic components among smokers, our study identified a modest protective link between early smoking and blood pressure in addition to a remarkable harmful association with high-density lipoprotein cholesterol levels exclusively in the escalator group during the developmental stage to young adulthood, using adjusted analyses.

Association of Dietary Polyphenol Intakes with Metabolic Syndrome and its Components: Tehran Lipid and Glucose Study.

This study was conducted to assess the prospective association between dietary polyphenols intakes and risk of metabolic syndrome (MetS) and its components. Participants in this study (n=4559) were selected from among the adults of the Tehran Lipid and Glucose Study (TLGS) with an average follow-up of 5.9+2.5 years. Biochemical and anthropometric variables were measured at baseline and follow-up examinations. A reliable and valid semi-quantitative food frequency questionnaire was used to evaluate dietary intakes. The incidence of MetS and its components in relation to polyphenols and its subclasses (phenolic acids, flavonoids, lignans, and stilbenes) was evaluated using multivariable Cox proportional hazard regression models. Of the 4559 subjects who enrolled in the present study, 1765 were male aged 38.6+14.2 y and 2794 were female aged 35.9+11.7 y. The hazard ratios of MetS were 25% lower in Q2 (HR, 95% CI: 0.75, 0.64‒0.88), 22% lower in Q3 (HR, 95% CI: 0.78, 0.65‒0.94) and 24% lower in Q4 (HR, 95% CI: 0.76, 0.61‒0.95) in comparison to Q1, whereas the results for subclasses of polyphenol were non-significant. The risk of high blood pressure (BP) reduced from quartiles 1 to 4 for phenolic acid (HR: 1.00, 0.88, 0.79, 0.80, Ptrend=0.03). The risk of low high-density lipoprotein cholesterol (HDL-C) increased across quartiles of phenolic acid (HR: 1.00, 1.22, 1.07, 1.30, Ptrend=0.02). This study highlights the potential protective role of total dietary polyphenols in the prevention of MetS. These findings could be the starting point of upcoming trials to illuminate the optimal level of polyphenols deriving from the intake of polyphenol-rich diets to prevent MetS.

Adiposity trajectories and cardiovascular disease risk in women: a population-based cohort study with a focus on menopausal status

ObjectivesA single measurement of adiposity indices could predict the incidence of cardiovascular disease (CVD); nonetheless their long-term pattern and its association with incident CVD are rarely studied. This study aimed to determine distinct trajectories of adiposity indices among participants of Tehran Lipid and Glucose Study (TLGS) and their association with incident CVD. Furthermore, this study aimed to investigate whether this association differed among individuals according to their menopausal status.MethodA total of 6840 women participated in TLGS, aged 20 years and older were included in this study; they were followed for a median of 16 years. Body mass index (BMI), waist circumference (WC), conicity index (CI) and body roundness index (BRI) were included in the analysis as adiposity indices. The cohort outcome panel of medical specialists identified the CVD outcomes. Trajectory analyses were used to identify homogeneous distinct clusters of adiposity indices trajectories. The association between the trajectory group membership and incident CVD were explored by Cox proportional hazard models, with unadjusted and adjusted model for baseline age, physical activity, smoking status, menopause and family history of CVD.ResultsThree BMI trajectory groups of low, medium, and high and two trajectories for WC, BRI and CI were identified. Adjusted cox proportional hazard models revealed significant associations between the hazard of CVD experience and the high trajectory group of the BMI (HR: 2.06, 95% CI: 1.38-3.07), WC (HR: 2.71, 95% CI: 1.98-3.70), CI (HR: 1.87, 95% CI: 1.26-2.77) and BRI (HR: 1.55-95% CI: 1.12-2.15), compared to the low trajectory group. Subgroup analysis based on the menopausal status of participants showed that the HR of CVD incidences for all of trajectories adiposity indices, except BMI, was statistically significant. Adjusted cox proportional hazard models, in those women not reached menopause during study, revealed that the HR (95% CI) of CVD incidences for high trajectory of BMI, WC, CI and BRI were 2.80 (1.86-7.05); 2.09 (1.40-6.16); 1.72 (1.42-5.61), and 3.09 (1.06-9.01), respectively. These values for those were menopause at the initiation of the study were 1.40 (1.11, 2.53); 1.65 (1.04-2.75); 1.69 (1.01-2.87), and 1.61 (0.98-2.65), respectively.ConclusionOur findings suggest that adiposity trajectories, particularly central adiposity index of CI, could precisely predict the CVD risk. Consequently, preventive strategies should be tailored accordingly.

Socio-behavioral determinants of health-related quality of life among patients with type 2 diabetes: comparison between 2015 and 2018

IntroductionType 2 diabetes (T2D) is a common chronic disease that significantly affects an individual’s overall health and well-being. The aim of this study is to investigate the factors that influence the health-related quality of life (HRQoL) of patients with T2D.MethodsThis study conducted using data from 6th phase (2015–2017) and 7th phase (2018–2022) of the Tehran Lipid and Glucose Study (TLGS). Data were collected through a combination of interviews, physical examinations, and laboratory tests. Quality of life questionnaire (SF-12) that consists of 12 questions was used to assess physical and mental health functioning. The generalized estimating equation model was used to assess the association between socio-behavioral factors and changes in HRQoL.ResultsThe study included 498 patients with T2D. The changes in HRQoL in patients with T2D followed a sex-specific pattern. Analysis of the physical component score (PCS) and the mental component score (MCS) showed a non-significant change in the total score during the three-year longitudinal study. However, the role physical (RP) of the PCS and the social functioning (SF) of the MCS showed a statistically significant change during this period. In addition, sex, body mass index (BMI), and having cardiovascular disease (CVD) and chronic kidney disease (CKD) showed a significant association with RP changes, and only job status showed a significant association with SF changes.ConclusionsBy recognizing the sex-specific patterns in HRQoL changes and understanding the multifaceted nature of factors such as BMI, CVD and CKD, healthcare professionals can develop targeted interventions that go beyond traditional diabetes management.

Endogenous estrogen exposure and hypertension risk; a population-based cohort study with about two decades of follow-up.

The impact of endogenous estrogen exposure (EEE) on hypertension (HTN) incidence has not been investigated yet. This study aimed to evaluate HTN incidence in women with different endogenous estrogen durations. Information was gathered from the Tehran Lipid and Glucose Study (TLGS) to conduct current research. At the initiation of the study, 4463 post-menarche normotensive women, including 3599 premenopausal and 864 menopausal women, were included. EEE was calculated for each woman, and they were followed up for the HTN event. According to the EEE, the hazard ratios and 95% confidence intervals (CI) for the HTN event were presented using Cox proportional hazards regression models (unadjusted and adjusted). The median (interquartile range) of follow-up (between menarche and the date of HTN incidence or last follow-up) was 33.2(25.1, 42.3) years. The event of menopause occurred in 31.8% of participants. The unadjusted model's findings illustrated that the EEE z-score was inversely associated with HTN incidence in post-menarcheal women [unadjusted hazard ratio (HR) 0.47, 95% CI 0.44, 0.50], meaning that the risk of HTN decreased by 53% for every 1-SD rise in the EEE z-score. After adjusting for potential confounders, the results showed no statistically significant changes (adjusted HR 0.46, 95% CI 0.43-0.49). In participants with prehypertension at baseline, the hazard of HTN decreased by 56% per 1-SD rise in the EEE z-score. This longitudinal study demonstrated the protective effect of a longer EEE duration on HTN risk, even among those with prehypertension status.

Association Between Insulin Resistance Indices and Liver Function Parameters Among Women With Polycystic Ovary Syndrome.

This study aimed to investigate whether polycystic ovary syndrome (PCOS) status changes the association between insulin resistance (IR) indices and liver function parameters among women. This is a cross-sectional, population-based study. We selected 1101 subjects aged ≥20 years from participants of Tehran Lipid and Glucose Study (TLGS). All of them had known the status of PCOS, and all variables were related to the IR indices and liver function parameters. The main outcome measures were TG/HDL-C and triglyceride-glucose (TyG) and liver function parameters (hepatic steatosis index [HSI], alanine transaminase [ALT] and aspartate transaminase [AST]). In the present study, there was no significant difference between the PCOS and the non-PCOS regarding the presence of liver function abnormalities. A model adjusted by age and BMI showed that the upper tertile of TyG index was positively associated with high AST (OR = 3.04 [95% CI: 1.20-7.68], p < 0.05), high ALT (4.76 [3.07-7.36], p < 0.05) and high HSI (8.44 [1.82-39.17], p < 0.05). Although the history of diabetes had a positive impact on elevated AST (1.66 [1.15, 2.40], p < 0.05), the third tertile of TG/HDL-C was associated with increased odds of elevated ALT (3.35 [2.21-5.06]) and HSI (6.55 [1.17-36.46]), whereas the second tertile of TG/HDL-C (OR = 2.65, CI 95%: 1.74-4.03) was also positively associated with elevated ALT. PCOS had no significant association with elevated liver function tests. The highest tertile of TyG index and the TG/HDL-C ratio as a surrogate of IR might play a role in detecting abnormalities of liver function parameters among women. However, PCOS status cannot change the association between IR and liver dysfunction.

Optimizing cardiovascular disease mortality prediction: a super learner approach in the tehran lipid and glucose study

Background & aimCardiovascular disease (CVD) is the most important cause of death in the world and has a potential impact on health care costs, this study aimed to evaluate the performance of machine learning survival models and determine the optimum model for predicting CVD-related mortality.MethodIn this study, the research population was all participants in Tehran Lipid and Glucose Study (TLGS) aged over 30 years. We used the Gradient Boosting model (GBM), Support Vector Machine (SVM), Super Learner (SL), and Cox proportional hazard (Cox-PH) models to predict the CVD-related mortality using 26 features. The dataset was randomly divided into training (80%) and testing (20%). To evaluate the performance of the methods, we used the Brier Score (BS), Prediction Error (PE), Concordance Index (C-index), and time-dependent Area Under the Curve (TD-AUC) criteria. Four different clinical models were also performed to improve the performance of the methods.ResultsOut of 9258 participants with a mean age of (SD; range) 43.74 (15.51; 20–91), 56.60% were female. The CVD death proportion was 2.5% (228 participants). The death proportion was significantly higher in men (67.98% M, 32.02% F). Based on predefined selection criteria, the SL method has the best performance in predicting CVD-related mortality (TD-AUC > 93.50%). Among the machine learning (ML) methods, The SVM has the worst performance (TD-AUC = 90.13%). According to the relative effect, age, fasting blood sugar, systolic blood pressure, smoking, taking aspirin, diastolic blood pressure, Type 2 diabetes mellitus, hip circumference, body mss index (BMI), and triglyceride were identified as the most influential variables in predicting CVD-related mortality.ConclusionAccording to the results of our study, compared to the Cox-PH model, Machine Learning models showed promising and sometimes better performance in predicting CVD-related mortality. This finding is based on the analysis of a large and diverse urban population from Tehran, Iran.

Higher ultra-processed food intake is associated with an increased incidence risk of cardiovascular disease: the Tehran lipid and glucose study

BackgroundCardiovascular disease (CVD) is a major cause of death worldwide, although limited data are currently available regarding the impact of consuming ultra-processed food (UPF) on its incidence. Given the increased consumption of UPF in Iran, we aimed to investigate the association between UPF intake and CVD risk.MethodsIndividuals without CVD (n = 2050) aged ≥ 30 years old were recruited from the Tehran Lipid and Glucose Study (TLGS). Dietary data were collected using a validated food frequency questionnaire (FFQ) and UPF intakes were assessed based on the Nova food classification. Multivariable Cox proportional hazard models adjusted for potential confounders were used to estimate the hazard ratio (HR) and 95% confidence intervals (95% CI) for the risk of CVD across tertiles of UPF intake.ResultsA 10.1% incidence of CVD occurred over a median follow-up of 10.6 years, with a 22% increase in CVD risk per each 50 g/day UPF intake. Participants with the highest intake of UPF had a 68% greater incidence of CVD compared to those with the lowest intake (HR = 1.68, 95% CI=1.14–2.48) after controlling for potential confounders. Regarding sub-groups of UPF, participants in the 3rd tertile compared to the reference had a significantly increased risk of CVD (HR = 1.56, 95% CI=1.04–2.34). Nevertheless, intake of bread, fast food, sweetened beverages, sweets and desserts, high-fat dairy products, and other UPFs were not associated with greater CVD risk.ConclusionOur findings support the hypothesis that the incidence of CVD is enhanced with the higher consumption of UPF in a representative sample of the Iranian population.

Bibliometric overview of the Tehran Lipid and Glucose Study (TLGS) publications from 2000 to 2022.

The present study was conducted to analyze the publications of the Tehran Lipid and Glucose Study (TLGS) and assess its scientific productions during the last 23 years. The required data were retrieved from the Scopus database. The advanced search was chosen, and the search query included terms related to the TLGS. Search and retrieval of data were conducted on August 30, 2022. Bibliometric indicators have been used at three levels in this research including the level of documents, journals, and authors. Also, the knowledge structure of this set was analyzed at the level of social structure and the level of conceptual structure. Data analysis and visualizations was performed using Bibliometrix and VOSviewer software. A total of 870 documents related to the TLGS have been indexed in the Scopus from 2000 to 2022, and 1148 authors have participated in the relevant studies. 66.4% of the TLGS documents were published in journals with Q1 subject area quartiles. There was an annual growth rate of 20% and average citations per document of 16.5. There was a co-authorship per document of 5.6 and an international co-authorship of 8.7%. According to the co-occurrence network for keywords, the most common areas in the TLGS published documents were nutrition, epidemiologic issues, cardiometabolic-related biomarkers, diabetes, hypertension, lifestyle variables and genetic studies. Over the past 23 years, the TLGS has successfully addressed a wide range of inquiries pertaining to cardiometabolic and nutritional issues in Iran. The remarkable achievements of the TLGS act as a catalyst, advocating for the planning and implementation of additional cohort studies that specifically focus on non-communicable diseases within the Iranian population.