Tehran Lipid And Glucose Study Research Articles

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

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

Association of ideal cardiovascular health metrics with incident low estimated glomerular filtration rate: More than a decade follow-up in the Tehran Lipid and Glucose Study (TLGS).

To evaluate the association between ideal cardiovascular health metrics (ICVHM) and incident low estimated glomerular filtration rate (eGFR) among the Iranian population. The study population included 6927 Iranian adults aged 20-65 years (2942 male) without prevalent low eGFR [i.e., eGFR < 60 ml/min/1.73 m2] and free of cardiovascular disease. The ICVHM was defined according to the 2010 American Heart Association. The multivariable Cox proportional hazards regression analysis was used to calculate the hazard ratios (HRs) of ICVHM both as continuous and categorical variables. Over the median of 12.1 years of follow-up, we found 1259 incident cases of low eGFR among the study population. In this population, ideal and intermediate categories of body mass index (BMI) and blood pressure (BP) and only the ideal category of fasting plasma glucose (FPG) significantly decreased the risk of developing low eGFR; the corresponding HRs and (95% confidence intervals) were (0.87, 0.77-0.99), (0.84, 0.76-0.99), (0.79, 0.68-0.93), (0.70, 0.60-0.83) and (0.76, 0.64-0.91). Also, one additional ICVHM was associated with a reduced risk of low eGFR for the global (0.92, 0.88-0.97) and biological cardiovascular health (0.88, 0.82-0.93) in these participants. A sensitivity analysis using the interval-censoring approach demonstrated that our method is robust, and results remained essentially unchanged. In a subgroup population with dietary data (n = 2285), we did not find the beneficial impact of having intermediate/ideal categories of nutrition status compared to its poor one on incident low eGFR. We found a strong inverse association between having higher global ICVHM with incident low eGFR among the non-elderly Iranian population; the issue is mainly attributable to normal BP, BMI, and FPG levels.

Severity of adipose tissue dysfunction is associated with progression of pre-diabetes to type 2 diabetes: the Tehran Lipid and Glucose Study

BackgroundThe association of prediabetes (Pre-DM) regression and progression with visceral adiposity index (VAI) and adipose tissue dysfunction (ATD) remains to be investigated.MethodsThe present cohort study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS) on 1458 Pre-DM cases (aged ≥ 21 years) who were followed for nine years. VAI was estimated based on waist circumference, body mass index, triglycerides, and high-density lipoprotein cholesterol. ATD status (i.e., absent, mild-moderate, and severe) was defined based on the age-stratified cutoff values of VAI. Multinomial logistic regression models with adjustment of potential confounders were used to estimate the chance of Pre-DM regression to normoglycemia or progression to T2D across ATD status.ResultsDuring the study follow-up, 39.0% of the participants developed T2D, and 37.7% returned to normoglycemia. Compared to mild-moderate ATD, Pre-DM subjects with severe ATD had a higher risk of developing T2D by 45% (OR = 1.45, 95% CI = 11.08–1.93). Severe ATD was also associated with a decreased chance of returning to normoglycemia by 26% (OR = 0.74, 95% CI = 0.55–0.99). Participants with severe ATD had significantly higher fasting (overall mean = 111, 95% CI = 109–112 vs. 106, 95% CI = 105–108 mg/dL) and 2h-serum glucose (overall mean = 165, 95% CI = 161–168 vs. 153, 95% CI = 149–156 mg/dL) concentrations over time.ConclusionSevere ATD was associated with an elevated risk of developing T2D and longitudinal poor-glycemic controls in Pre-DM subjects. ATD may be a simple and useful index for detecting subjects at a higher risk of Pre-DM progression to T2D, allowing for timely intervention strategies.

Comprehensive evaluation of body composition in a wide age range of Iranian adults using bioelectrical impedance analysis: Tehran Lipid and Glucose Study.

To evaluate sex- and age-stratified body composition (BC) parameters in subjects with wide age range of 20-79 years. Cross-sectional. Participants of Tehran Lipid and Glucose Study (TLGS). Two thousand nine hundred seventy participants met our inclusion criteria. They were divided into five age groups, and BC parameters were analysed based on sex and age using a bioelectrical impedance analyser (BIA). The mean age of the participants was 42·1 ± 12·5 years, and 54 % of them were males. The mean BMI was 26·7 ± 3·7 kg/m2. Obesity indices were significantly higher in females (P < 0·001); however, skeletal muscle mass (SMM) and fat-free mass (FFM) were significantly higher in males (P < 0·001). Both SMM and FFM decreased significantly after the age of 50 years. Obesity indices significantly increased from the age group of 20-29 to 30-39 years in males and the age groups of 30-39 to 40-49 years and 40-49 to 50-59 years in females. The fat mass ratio (fat mass/SMM) showed two peaks in both sexes (after the ages of 30 and 50 years in males and 40 and 50 years in females). A strong correlation was found between BMI and percentage of body fat (r = 0·823 in females v. r = 0·768 in males). This is the first community-based study in the MENA region identifying sex- and age-stratified BC values using BIA. Our findings can be used as a reference for comparison in appropriate settings.

Factors associated with smoking intensity among adult smokers: findings from the longitudinal cohort of the Tehran lipid and glucose study

BackgroundSmoking is a significant public health problem, and there is a scarcity of documents regarding its severity, particularly in developing countries. This study aimed to determine factors related to the number of cigarettes consumed daily by adult smokers in Tehran.MethodsThis study was conducted within the framework of the longitudinal study of Tehran Lipid and Glucose Study (TLGS). The study included 786 adult smokers living during four consecutive follow-ups from 2005 to 2016. The intensity of smoking was measured by the number of cigarettes consumed daily by adult smokers. Data analysis was done longitudinally and based on the mixed effects zero-inflated discrete Weibull (ZIDW) regression model.ResultsThe mean age of the individuals was 40.35 ± 12.68 years, and 643 (81.8%) of them were men. Also, 52.7% of individuals were daily smokers, 15.6% were occasional smokers, and 31.7% were non-smokers who became smokers during the study. Variables of age 1.005 (95%CI: 1.001–1.008), gender of male 1.196 (95%CI: 1.051–1.39), and marital status (divorced/widowed vs. single) 1.168 (95%CI: 1.015–1.39) were positively associated with smoking intensity. Education level (master and higher vs. illiterate) 0.675 (95%CI: 0.492–0.926)), employment status (student vs. unemployed) 0.683 (95%CI: 0.522–0.917), (housewife vs. unemployed) 0.742 (95%CI: 0.606–0.895), (Unemployed with income vs. unemployed) 0.804 (95%CI: 0.697, 0.923), implementation of smoking prohibition regulations (yes vs. no) 0.88 (95%CI: 0.843–0.932), and history of cardiovascular disease in male relatives (yes vs. no) 0.85 (95%CI: 0.771–0.951) were associated with lower smoking intensity.ConclusionWe showed that demographic factors are associated with the intensity of smoking among adults and should be considered in policymakers’ intervention programs to reduce smoking and quit smoking.

The association between leisure-time physical activity and blood pressure changes from adolescence to young adulthood: Tehran Lipid and Glucose Study

The effectiveness of long-term leisure time physical activity (LTPA) on blood pressure (BP) changes is still under debate. Since adolescence lifestyle behaviors shape the adulthood health profile, this study aimed to investigate the sex-specific impact of LTPA on BP changes from adolescence to young adulthood. This longitudinal study uses the data of 1412 adolescents (52% females) aged 12–18 years through a median follow-up of 12.2 years in the Tehran Lipid and Glucose Study (TLGS) framework. LTPA was calculated using the reliable and valid Iranian version of the modified activity scale (MAQ), and BP was measured at least twice by trained physicians. The linear mixed model was used to examine the study variables, considering individual and intrapersonal differences during the study. The majority of participants consistently demonstrated insufficient LTPA throughout the follow-up assessments, ranging from 54.7 to 67.1% for males and 77.7–83.4% for females. Despite a declining trend in LTPA (β = − 2.77 for males and β = − 1.43 for females), an increasing trend was noticeable in SBP, DBP, and BMI (β = 1.38, β = 1.81, β = 0.97 for males, and β = 0.10, β = 0.20, β = 0.97 for females, respectively). The unadjusted model revealed a significant trend in all variables for both sexes, except for female BP (P = 0.45 for SBP and P = 0.83 for DBP). Using the adjusted model, no significant association was observed between LTPA and changes in BP over time in both sexes. Our study indicates no association between LTPA and BP changes from adolescence to young adulthood. Insufficient LTPA levels, particularly among Iranian females, are likely the primary factor. Further research is crucial to identify appropriate LTPA levels to promote cardiovascular health and implement targeted interventions to achieve optimal LTPA levels in the Iranian population.

Cumulative burden and trajectories of body mass index and blood pressure from childhood and carotid intima-media thickness in young adulthood

There are significant gaps in understanding of the association between levels and rate of change of body mass index (BMI) and blood pressure (BP) at different ages during childhood and carotid intima-media thickness (CIMT) in adulthood. We investigated the association between trajectories of BMI and BP from childhood to adulthood and adult CIMT among Iranian participants in the Tehran Lipid and Glucose Study (TLGS) cohort. A total of 1334 participants (692 men), from the TLGS cohort (1999–2018) with repeated measurements of BMI and BP (2–6 times) from childhood (3–18 years) to young adulthood (20–40 years) were selected. Trajectory parameters included levels and linear slopes of BMI and BP growth curve models, and cumulative burden defined as the area under those curves (AUC). After adjusting for confounders, AUC of BMI and diastolic blood pressure (DBP) were significantly associated with high CIMT in adulthood, with the standardized odds ratios (OR) and 95% confidence interval (95% CI) of 1.35 (1.12–1.62) and 1.27 (1.01–1.60), respectively. Associations between level-independent slopes of BMI and adult CIMT were significantly positive (ORs: 1.27 to 1.26) during childhood ages (3–18 years). Further, levels of BMI (ORs: 1.23 to 1.29) and DBP (ORs: 1.25 to 1.33) during the ages of 13–18 and 11–17 years, respectively, were significantly associated with CIMT in adulthood (all P < 0.05). The cumulative burden of BMI and DBP was associated with CIMT in adulthood. Adolescence is a crucial period for high CIMT, which has implications for early prevention of atherosclerosis.

Association between estimated glomerular filtration rate slope and cardiovascular disease among individuals with and without diabetes: a prospective cohort study

BackgroundPrevious studies have reported an association between a significant decline in estimated glomerular filtration rate (eGFR) over time and an increased risk of cardiovascular disease (CVD). This study aimed to investigate the association between the eGFR slope and CVD among individuals with and without diabetes.MethodsThis prospective cohort study was conducted within the Tehran Lipid and Glucose Study (TLGS) framework. We studied 6919 adults aged 20–70 years, including 985 with diabetes and 5934 without diabetes. The eGFR slope was determined based on repeated measurements of eGFR through linear mixed-effects models. A multivariable Cox proportional hazard model was employed to evaluate the association between eGFR slope, both in continuous and categorical form, and the risk of CVD.ResultsThe slopes of eGFR exhibited a bell-shaped distribution, with a mean (standard deviation (SD)) of -0.63 (0.13) and − 0.70 (0.14) ml/min per 1.73 m2 per year in individuals with and without diabetes, respectively. During a median follow-up of 8.22 years, following the 9-year eGFR slope ascertainment period, a total of 551 CVD events (195 in patients with diabetes) were observed. Among individuals with diabetes, a steeper decline in eGFR slope was significantly associated with a higher risk of CVD events, even after adjusting for baseline eGFR, demographic factors, and traditional risk factors for CVD; slopes of (-1.05 to -0.74) and (-0.60 to -0.52) were associated with 2.12 and %64 higher risks for CVD, respectively, compared with a slope of (-0.51 to 0.16). Among individuals without diabetes, the annual eGFR slope did not show a significant association with the risk of CVD.ConclusionMonitoring the eGFR slope may serve as a potential predictor of CVD risk in individuals with diabetes.

Dietary fatty acid patterns and risk of metabolic syndrome: Tehran lipid and glucose study

BackgroundThe association between individual dietary fatty acids (FAs) and risk of metabolic syndrome (MetS) has been investigated in previous studies. However, synergistic or additive effects of multiple FA have received less attention. Hence, we aimed to determine the major dietary FA patterns and evaluate the association between FA patterns and risk of MetS.MethodsDietary intakes of 1713 MetS-free adults who participated in the third phase of the Tehran Lipid and Glucose Study (TLGS) were assessed using a validated 168-items food frequency questionnaire. FA patterns were obtained by principal component analysis (PCA). Adjusted Hazard Ratios (HRs) and 95% confidence intervals (CIs) were calculated for the association of MetS incident with the extracted FA patterns.ResultsFour major FA patterns were identified through PCA of the 24 FAs consumed: “short- and medium-chain saturated fatty acid (SFA) pattern”, “long-chain FA pattern”, “omega-3 PUFA pattern”, and “long-chain SFA pattern”. There was no significant association between dietary FA patterns and risk of MetS incidence.ConclusionsWe found no significant association between FA patterns and risk of MetS. More prospective cohort studies and clinical trials are needed to clarify the issue.

Effect of weight change on the association between overall and source of carbohydrate intake and risk of metabolic syndrome: Tehran lipid and glucose study

BackgroundIn this prospective cohort study, we aimed to evaluate the association between dietary carbohydrates, whole grains, refined grains, and simple sugar with the risk of metabolic syndrome (MetS) and assess the effect of weight change on these associations.MethodsThis study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS). We included 1915 healthy participants with complete demographic, anthropometric and dietary measurements, among whom 591 developed MetS during 8.9 years of follow-up. Intake of dietary carbohydrates, whole grains, refined grains, and simple sugar was assessed with a validated semi-quantitative food frequency questionnaire. Multivariable adjusted Cox regression was used to estimate hazard ratios (HRs) for MetS events across tertiles of dietary variables. Using joint classification, the effect of weight change on the association between dietary variables and risk of MetS was assessed by Cox regression.ResultsCarbohydrate intake was not associated with the risk of MetS in multivariable-adjusted models. Whole grains intake was inversely associated with the risk of MetS (HR: 0.78, CI: 0.63–0.98), while this association disappeared after adjustment for weight change. The risk of MetS increased by 11% (1.11, 1.09–1.14) for each 3% energy increment from simple sugar, and by 5% (1.05, 1.03–1.08) for each 1 serving/day increment in refined grains. Consumption of refined grains increased the risk of MetS; an effect modification of this association was found by weight change. Among subjects with weight loss, intake of refined grains < median intake decreased the risk of MetS (0.59, 0.41–0.87). However, consumption of refined grains ≥ median intake increased the risk of MetS in individuals with weight gain (1.47, 1.08–2.01). Simple sugar was positively associated with an increased risk of MetS, after adjustment for weight change (3.00, 2.37–3.82). In joint classification, intake of simple sugar greater than median intake increased the risk of MetS, independent of weight change.ConclusionOur findings suggest an effect modification by weight change on the association between carbohydrates, and refined grains intake and the risk of MetS. Weight loss along with lower consumption of carbohydrates, and refined grains reduced the risk of MetS. However, simple sugar intake, regardless of weight change, was associated with an increased risk of MetS.

Association of baseline and changes in adiponectin, homocysteine, high-sensitivity C-reactive protein, interleukin-6, and interleukin-10 levels and metabolic syndrome incidence: Tehran lipid and glucose study

BackgroundMetabolic syndrome (MetS) is accompanied by chronic low-grade inflammation, and inflammatory markers like high-sensitivity C-reactive protein(hs-CRP), interleukin-6(IL-6), and homocysteine(Hcy) contribute to inflammation, obesity, and insulin resistance. Adiponectin(AdipoQ) and interleukin-10(IL-10) are anti-inflammatory markers that play protective roles in MetS. This study aimed to investigate the association between these biochemical marker changes and MetS in a sample of the Tehranian population during six years of follow-up. MethodsIn this longitudinal study, 340 adults at baseline and after a six-year follow-up, aged ≥18 years, were selected randomly from the Tehran Lipid and Glucose Study (TLGS). MetS was defined according to the Joint Interim Statement (JIS) criteria. Individuals were categorized into four groups based on their MetS status at baseline and follow-up: 1) non-MetS: participants who did not have MetS at both baseline and follow-up; 2) incident MetS: participants who did not have MetS at baseline but developed MetS during the follow-up ; 3) recovery MetS: participants who had MetS at baseline but no longer had MetS during the follow-up; 4) persistent MetS: participants who had MetS both at baseline and follow-up. ResultsThe mean follow-up time was 6.1 years. There were 176 subjects in the non-MetS group, 35 in the incident MetS group, 41 in the recovery MetS group, and 88 in the persistent MetS group. Increases in the levels of both hs-CRP 1.40 (95% CI: 1.15, 1.71, p = 0.001) and IL-6 1.09 (95% CI: 1.03, 1.17, p = 0.004) significantly increased the odds of the incident and persistent MetS, respectively. The area under the ROC curve (AUC) was more than 0.69 (p < 0.000) for hs-CRP in predicting MetS incidence and more than 0.86 (p < 0.000) for IL-6 in predicting MetS persistence. ConclusionAfter a six-year average follow-up, hs-CRP and IL-6 levels were deemed more reliable predictors of MetS incidence and persistence, respectively.

How Do Active and Passive Cigarette Smokers in Iran Evaluate Their Health? A Sex-Specific Analysis on the Full-Spectrum of Quality of Life.

This study aimed to determine the sex-specific effects of active and passive cigarette smoking on the full spectrum of health-related quality of life (HRQoL) among a sizeable adult population. This study was conducted within the Tehran Lipid and Glucose Study (TLGS) framework. Participants included 7478 adults in the last examination of the TLGS. We used a quantile regression model to compare sex-specific HRQoL distributions among non-, current, and passive smokers. Two-step cluster analysis was used to consider the synergic effects of confounder variables. In men, current smoking was negatively associated with only mental HRQoL in all percentiles of its distribution with a decrease in absolute estimation values from the lowest (5 th: β=-6.59, p<0.001) to the highest (90 th: β=-0.93, p=0.027). Also, passive smoking was negatively associated with men's physical HRQoL in the upper percentiles of its distribution (75 th: β=-1.12, p=0.010; 90 th: β=-1.26, p=0.016). In women, the current (β= -4.17 to -4.45 for 25 th to 90 th percentiles) and passive smokers (β= -2.05 to -4.25 for 10 th to 90 th percentiles) had lower mental HRQoL in the mentioned percentiles. Also, the current smoking had a negative association with the 5 th percentile (β=-2.04, p=0.008), and a positive association with the 50 th (β=1.94, p< 0.008) and 75 th percentile of physical HRQoL (β=2.25, p=0.004). The present study showed the harmful effect of smoking on mental HRQol in all participants. In contrast, the physical effect of smoking was only observed in female active smokers and at the extreme levels of the physical HRQoL spectrum. According to the harmful effect of smoking on HRQoL, understanding active and passive smokers' perceptions of how smoking impacts their health is critical for tobacco control programs. Since most previous studies of smoking and HRQoL have mainly focused on the extreme parts or central values of the HRQoL distribution, the use of a multiple regression approach enables the evaluation of other parts of the conditional distribution of the outcome variable. This study demonstrated the prominent effect of smoking on the mental HRQoL as well as the more serious public health burden of passive smoking in women.

The Hidden Link between Polycystic Ovary Syndrome and Kidney Stones: Finding from the Tehran Lipid and Glucose Study (TLGS).

We aimed to investigate the association between kidney stones and polycystic ovarian syndrome (PCOS). In a cross-sectional study, data from the Tehran Lipid and Glucose Study (TLGS) were used to investigate the risk of kidney stones in women with Polycystic Ovary Syndrome (PCOS). Four distinct phenotypes of PCOS, as defined by the Rotterdam criteria, were examined in a sample of 520 women and compared to a control group of 1638 eumenorrheic non-hirsute healthy women. Univariate and multivariable logistic regression models were employed for analysis. The four PCOS phenotypes were classified as follows: Phenotype A, characterized by the presence of all three PCOS features (anovulation (OA), hyperandrogenism (HA), and polycystic ovarian morphology on ultrasound (PCOM)); Phenotype B, characterized by the presence of anovulation and hyperandrogenism; Phenotype C, characterized by the presence of hyperandrogenism and polycystic ovarian morphology on ultrasound; and Phenotype D, characterized by the presence of anovulation and polycystic ovarian morphology on ultrasound. The prevalence of a history of kidney stones was found to be significantly higher in women with Polycystic Ovary Syndrome (PCOS) compared to healthy controls (12.5% vs. 7.7%, p = 0.001). This increased prevalence was observed across all PCOS phenotypes (p < 0.001). After adjusting for potential risk factors, including age, family history of kidney stones, waist-to-height ratio, total cholesterol, and low-density lipoprotein, the odds ratio for kidney stones in women with PCOS was found to be 1.59 [95% CI: 1.12-2.25, p = 0.01], indicating a 59% increase in risk compared to healthy women. Women with PCOS Phenotype A [OR: 1.97, 95% CI: 1.09-3.55, p = 0.02] and Phenotype D [OR: 3.03, 95% CI: 1.24-7.41, p = 0.01] were found to be at a higher risk for kidney stones. Women with Polycystic Ovary Syndrome (PCOS), particularly those exhibiting menstrual irregularities and polycystic ovarian morphology on ultrasound (PCOM), have been found to be two to three times more likely to develop kidney stones. This increased prevalence should be taken into consideration when providing preventive care and counseling to these individuals.

Adherence to a modified nordic diet and the risk of cardiovascular events in a non-nordic population: a prospective cohort study.

Even though studies have demonstrated that the Nordic diet is beneficial for cardiovascular disease (CVD) risk factors, it is unknown if this diet is associated with actual CVD cases. So, the aim of this study was to investigate the association between a modified Nordic diet and the risk of CVD in non-Nordic adults. In this cohort study, 2918 people who participated in the third phase of the Tehran Lipid and Glucose Study (TLGS) were examined. All participants had no CVD at the beginning of the study, which was monitored until 2018. The Nordic score was calculated using a validated food frequency questionnaire (FFQ). Patients' medical records were examined for cardiovascular events such as coronary heart disease (CHD), stroke, and mortality from CVD. The Cox proportional hazards model was used to assess the relationship between the Nordic score and the risk of CVD. During a median follow-up of 10.6 years, 203 subjects experienced cardiovascular events. The third and fourth quartiles of the Nordic score were associated with a 35% (HR: 0.65; 95% CI: 0.45, 0.95) and 60% (HR: 0.40; 95% CI: 0.27 to 0.65) reduced risk of CVD compared to the lowest quartile. Subgroup analyses revealed that a high Nordic score was inversely associated with a lower risk of CVD in adults older than 45 years of age, both sexes, and all BMI categories. Each 1-score increase in cereal consumption was associated with a 24% (HR: 0.76; 95% CI: 0.67 to 0.87) lower risk of CVD; low-fat milk with a 23% (HR: 0.77; 95% CI: 0.68 to 0.87); and fish with a 22% (HR: 0.78; 95% CI: 0.69 to 0.89) lower risk of CVD. We found that high Nordic score adherence may prevent cardiovascular events in non-Nordic populations. Cereals, fish, and low-fat milk were the primary components of the Nordic diet that indicated an inverse relationship with CVD.