The association between parental cardiovascular health status and the risk of obesity in their offspring: Tehran Lipid and Glucose Study.

BACKGROUND AND AIMS: Little is known about the association of parental cardiovascular risk factors with the risk of obesity in offspring. We aimed to investigate whether parental ideal cardiovascular health (ICVH) status was associated with the risk of general and central obesity in their young/adult offspring. METHODS AND RESULTS: Of individuals who participated in the 2012-15 phase of the Tehran Lipid and Glucose Study, 2395 pairs of parent-unmarried offspring aged ≥6 years were selected in this cross-sectional study. General and central obesity were defined based on Iranian BMI percentile reference data for offspring aged ≤18 years. For subjects aged ≥19 years, central obesity was defined based on the introduced cut-off points for Iranian adults. We employed the American Heart Association's 2020 impact goal criteria of ICVH. The mean ± SD age of fathers and mothers were respectively 55.4 ± 9.79 and 48.4 ± 9.88. About 55% of offspring were older than 19 years. Higher adherence to ICVH score in mothers was associated with lower risk of overweight/obesity in female offspring (OR for Q1-Q4: 1, 0.56, 0.57, 0.37, P < 0.05 for all quartiles). Among ICVH components, only ideal BMI status in fathers was observed to be associated with a lower risk of overweight/obesity in their male offspring. The risk of abdominal obesity decreased in female offspring with increasing total ICVH score in mothers. CONCLUSION: Higher adherence of parents to ICVH and its components was positively associated with a lower risk of general and abdominal obesity in their offspring. Our findings demonstrate that maternal-offspring relationship was stronger than paternal-offspring association.

Familial resemblance and family-based heritability of nutrients intake in Iranian population: Tehran cardiometabolic genetic study.

BACKGROUND: We aimed to investigate the familial resemblance of dietary intakes, including energy and nutrients, and the family-based heritability of dietary intake in different age-sex dyads of the Tehran cardiometabolic genetic study. METHODS: This cross-sectional study was conducted on 9,798 participants, aged ≥ 18 years, with complete data in each of the third, fourth, fifth, and sixth surveys of the Tehran Cardiometabolic Genetic study, who were eligible to enter the current study based on inclusion and exclusion criteria. Nutrient intake was determined using a valid and reliable food frequency questionnaire (FFQ). FCOR command of the S.A.G.E. software was used to estimate the intra-class correlation coefficients of all relative pairs to verify the family resemblance of dietary nutrient intakes. Classical likelihood-based is used to assess the family-based heritability of dietary nutrient traits. RESULTS: There were 4338 families with a mean family size of 3.20 ± 2.89, including 1 to 32 members (2567 constituent pedigrees and 1572 singletons) and 3627 sibships. The mean ± SD age of participants was 42.0 ± 15.2 years, and 44.5% were males. The heritability of nutrient intake ranged from 3 to 21%. The resemblance degree of energy intake and most nutrients between spouses or between parents and children is weak to moderate; however, a high resemblance of intake was observed for some food components, especially among spouses, including trans fatty acids (TFAs) (r:0.70), chromium (r:0.44), fiber(r:0.35), pantothenic acid (r:0.31), and vitamin C(r:0.31). Based on our findings, the resemblance of nutrient intake in spouses was greater than in parent-offspring. The similarity in parent-offspring nutrient intake was different, and the correlation in mother-girls nutrient intakes was greater than other parent-child correlations. Also, the lowest resemblance in nutrient intake was observed among siblings. CONCLUSIONS: Our findings suggested a weak-to-moderate similarity between the nutrient intakes of parents and offspring. The resemblance degree in nutrient intake varied between different family pairs; the strongest correlation of nutrients was observed between spouses, which includes TFAs, chromium, fiber, pantothenic acid, and vitamin C. The lowest correlation of nutrients was between siblings, such as carbohydrates, thiamine, niacin, and vitamin K. An individual's nutrient intake can somewhat be influenced by genetics, family relationships, and the effects of parents, although the significant influence of environmental factors should not be ignored.

Higher dietary flavonol and isoflavonoid intakes are associated with lower incidence of type 2 diabetes.

Background: Adequate evidence supports beneficial effects of plant-derived phytochemicals against type 2 diabetes (T2D). Among phytochemicals, dietary flavonoids is one of the superb candidates. The whole studies are carried out in Western populations, so it is needed to investigate the risk of T2D by dietary flavonoid intakes in ethnic origins and other regions to confirm these relations. This study was conducted to investigate whether the daily consumption of total flavonoid and its subclasses can affect the incidence of type 2 diabetes (T2D) in the Iranian population. Methods: Eligible adults (n=6547) were selected from among participants of the Tehran lipid and glucose study with an average follow-up of 3.0 years. Dietary intakes were assessed using a valid and reliable 168-item semi-quantitative food frequency questionnaire. Multivariate Cox proportional hazard regression models were used to estimate the development of T2D in relation to total intake of flavonoids. Results: This study was conducted on 2882 men and 3665 women, aged 41.3±14.6 and 39.0±13.4 years, respectively. After adjustment for several potential confounders (age, sex, diabetes risk score, physical activity, energy, fiber and total fat intakes), risk of T2D decreased from tertiles 1 to 3 for flavonols (HR (95% CI): 1.00, 0.86 (0.64-1.16), 0.87 (0.63-0.93), Ptrend=0.01) and isoflavonoids (HR (95% CI): 1.00, 0.84 (0.62-1.13), 0.64 (0.46-0.88), Ptrend=0.02), whereas non-significant results were found for total flavonoid and other subclasses of flavonoid. Conclusion: These results emphasize the potential protective role of flavonols and isoflavonoids rich food (e.g. apple, tea, soy, and dark chocolate) in the prevention of T2D.

Diet quality and anthropometric indices of patients undergone bariatric surgery: the prospective Tehran obesity treatment study.

BACKGROUND: Patients undergone bariatric surgery (BS) has long-term risks including decrease in diet quality, nutritional deficiencies and weight regain. This study focus on assessing dietary quality and food group components in patients one year after BS, the relationship between dietary quality score and anthropometric indices, and also evaluating the trend of body mass index (BMI) of these patients three years after BS. METHODS: A total of 160 obese patients (BMI ≥ 35 kg/m2) were undergone sleeve gastrectomy (SG) (n = 108) or gastric bypass (GB) (n = 52), participated in this study. They were assessed for dietary intakes using three 24-hour dietary recalls one year after surgery. Dietary quality was assessed using food pyramid for post BS patients and healthy eating index (HEI). Anthropometric measurements were taken pre-surgery and 1, 2 and 3 years after operation. RESULTS: The mean age of patients was 39.9 ± 11 years (79% female). The mean ± SD percentage of excess weight loss was 76.6 ± 21.0 one year after surgery. Intake patterns are generally (up to 60%) not consistent with the food pyramid. The mean total HEI score was 64 ± 12 out of 100. More than %60 of participants is exceeding the recommendations for saturated fat and sodium. The HEI score did not show significant relationship with anthropometric indices. The mean of BMI in SG group increased over three years of follow up, while in GB group, there were no significant differences in BMI during three years of follow up. CONCLUSIONS: These findings showed that patients had not healthy pattern intake one year after BS. Diet quality did not show significant relationship with anthropometric indices. The trend of BMI three years after surgery was different based on surgery types.

Evaluating machine learning-powered classification algorithms which utilize variants in the GCKR gene to predict metabolic syndrome: Tehran Cardio-metabolic Genetics Study.

BACKGROUND: Metabolic syndrome (MetS) is a prevalent multifactorial disorder that can increase the risk of developing diabetes, cardiovascular diseases, and cancer. We aimed to compare different machine learning classification methods in predicting metabolic syndrome status as well as identifying influential genetic or environmental risk factors. METHODS: This candidate gene study was conducted on 4756 eligible participants from the Tehran Cardio-metabolic Genetic study (TCGS). We compared predictive models using logistic regression (LR), Random Forest (RF), decision tree (DT), support vector machines (SVM), and discriminant analyses. Demographic and clinical features, as well as variables regarding common GCKR gene polymorphisms, were included in the models. We used a 10-repeated tenfold cross-validation to evaluate model performance. RESULTS: 50.6% of participants had MetS. MetS was significantly associated with age, gender, schooling years, BMI, physical activity, rs780094, and rs780093 (P < 0.05) as indicated by LR. RF showed the best performance overall (AUC-ROC = 0.804, AUC-PR = 0.776, and Accuracy = 0.743) and indicated BMI, physical activity, and age to be the most influential model features. According to the DT, a person with BMI < 24 and physical activity < 8.8 possesses a 4% chance for MetS. In contrast, a person with BMI ≥ 25, physical activity < 2.7, and age ≥ 33, has 77% probability of suffering from MetS. CONCLUSION: Our findings indicated that, on average, machine learning models outperformed conventional statistical approaches for patient classification. These well-performing models may be used to develop future support systems that use a variety of data sources to identify persons at high risk of getting MetS.

The resemblance of dietary intakes in three generations of parent-offspring pairs: Tehran lipid and glucose study.

The degree of similarity between dietary intakes of offspring and their parents may be different across various countries. This study aimed to investigate the correlation between food group intakes and dietary quality in three younger-middle-older generations by living arrangements. Individuals who participated in the 5th survey of the Tehran Lipid and Glucose Study, 1286 families (4685 subjects) with complete data for two or three generations were entered in this cross-sectional study. Genetic data management system from Progeny Software was used to error-check family data pedigree details. Dietary data were gathered using a valid and reliable food frequency questionnaire. The healthy eating index score was computed. Data of parents with their offspring were compared using paired t-test and partial correlation. The mean ages of grandfathers and grandmothers were 69.4 ± 7.9 and 63.7 ± 8.5 respectively. Of girls and boys who lived with their parents, about 59% were 20 years or older. The correlation of parents' dietary intake and their young offspring who lived with them was higher than that of parents and adult offspring who lived independently from their parents. The correlation of dietary quality and food group intakes in mother-offspring dyads (mother-son: 0.37, mother-daughter: 0.44) were higher than father-offspring (father-son: 0.34, father-daughter: 0.25) dyads. The dietary quality of parents was higher than that of offspring in both living statuses. The dietary intake of adult married offspring was not correlated with their parents; also there was no correlation between the dietary quality of younger and older generations. There were weak to moderate similarities between food group intakes of parent-offspring dyads that lived with their parents.

The association of priori and posteriori dietary patterns with the risk of incident hypertension: Tehran Lipid and Glucose Study.

BACKGROUND: The aim of this study was to investigate the association of dietary patterns with incident hypertension. MATERIALS/METHODS: This prospective study was conducted on 4793 individuals of Tehran lipid and glucose study participants, aged ≥ 18 years who were followed for a median of 6.3 years from 2008-2011 to 2016-2018. A valid and reliable semi-quantitative food frequency questionnaire was used to assess usual dietary intakes. Anthropometrics and blood pressure were assessed at baseline and during follow up examinations. Dietary patterns were derived using principal component analysis (PCA). Healthy eating index (HEI) and dietary approach to stop hypertension (DASH) score were measured based on dietary recommendations. Time-dependent Cox models adjusting for confounders were used to examine the association between dietary patterns and the risk of hypertension. RESULTS: During follow-up, a total of 727 incident cases of hypertension were identified. The mean ± SD age at baseline was 40.3 ± 13.5 and 37.9 ± 12.1 years in men and women, respectively. Two dietary patterns (the healthy and unhealthy) were extracted by PCA. Compared with participants in the first quartile, a 23% (HR: 1.23; 95%CI 1.00-1.53; P trend: 0.056) increased risk of hypertension was found in the fourth quartile of HEI score. This association was disappeared after further adjustment for confounders. Increasing DASH score, the healthy and unhealthy dietary pattern were not associated with risk of hypertension. CONCLUSION: Our findings showed that higher adherences to the posteriori- and priori-dietary patterns were not associated with risk of hypertension in this population.

Dietary diversity modifies the association between FTO polymorphisms and obesity phenotypes.

The current study aimed to evaluate the interaction of the dietary diversity score (DDS) and FTO polymorphisms concerning obesity phenotypes. The 4480 subjects of this cohort study were selected. The polymorphisms rs1121980, rs14211085 and rs8050136 were selected and genotyped. The weighted method was used to calculate the genetic risk score (GRS). Obesity marker changes were calculated. Those with minor allele carriers of rs1121980 had lower body mass index changes (Q1: 1.58 ± 0.60 vs. Q4: 0.13 ± 0.59) and visceral adiposity index (VAI) (Q1: -0.00 ± 0.02 vs. Q4: -0.04 ± 0.02) when they had higher DDS (P interaction = 0.05). Carriers of the minor allele of rs8050136 had significant VAI change across DDS quartiles (Q1: -0.01 ± 0.02 vs. Q4: -0.02 ± 0.02, P interaction = 0.05). No significant interaction was found between the GRS and DDS on general obesity. The pattern of dietary diversity may have a mediatory role in improving obesity markers in subjects with a more genetic predisposition to adiposity.

The association of dietary macronutrients composition with the incidence of cardiovascular disease, using iso-energetic substitution models: Tehran lipid and glucose study.

BACKGROUND AND AIMS: Dietary macronutrient composition plays an important role in the prevention of cardiovascular disease (CVD). This study aimed at assessing the iso-energetic substitution of dietary macronutrients in relation to the incidence of CVD. MATERIALS AND RESULTS: This prospective study was conducted on 5102 individuals of Tehran lipid and glucose study participants, aged 20-70 years who were followed for 5.3 years. A valid and reliable semi-quantitative food frequency questionnaire was used to assess dietary intakes. The hazard ratio of CVD for each 5% of energy from macronutrients at the expense of another macronutrient was calculated using the substitution model. During follow-up, a total of 206 CVD outcomes were identified. Mean age of participants (44.2% men) was 47.0 ± 12 and 45.6 ± 11 for men and women, respectively. Substituting 5% of energy from all types of macronutrients by 5% percentage of energy from combined saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) was associated with a decrease in the risk of CVD by almost 20%. Higher energy intake from total-, starchy-, and nonstarchy carbohydrates replaced by other macronutrients was not significantly associated with the risk of CVD. Each 5% of energy from animal protein (HR: 1.09 and CI: 1.02-1.16) independently increased the risk of CVD in the adjusted Cox proportional hazard regression analyses. CONCLUSION: Higher percentage of energy from animal protein independently increased the risk of CVD, replacement of SFA and MUFA together with other macronutrients was inversely associated with CVD risk.

Nutrient patterns and cardiometabolic risk factors among Iranian adults: Tehran lipid and glucose study.

BACKGROUND: The present study aimed to assess the relation between nutrient patterns and changes in adult anthropometric and cardiometabolic factors. METHODS: This study was conducted on 1637 adults participating in the Tehran Lipid and Glucose Study (2005-2008), who were free of cardiovascular diseases and cancer and had completed dietary data. They were followed to the next survey (2008-2011). Dietary intakes were collected and nutrient patterns were obtained. Three year changes in anthropometric and cardiometabolic factors were measured. RESULTS: Five nutrient patterns were extracted. The first pattern was characterized by "plant protein, thiamine, niacin, and minerals including phosphorus, zinc, copper, magnesium, manganese, and selenium". Animal protein, lactose, vitamin D, riboflavine, pantothenic acid, vitamin B12, calcium, phosphorus, and zinc" were loaded in the second pattern. The third and fourth patterns were characterized by "vitamin K, fiber, calcium, iron, manganese, and potassium", and "high correlation with starch, thiamine and folate, and negative correlation with mono and poly unsaturated fatty acids and vitamin E", respectively. The fifth pattern was high in Fructose, vitamins A, C, pyridoxine, and potassium. There was no association between nutrient patterns and 3-year changes in blood pressure and fasting blood glucose; whereas, per each quartile increment of the fifth pattern adjusted for potential confounders, triglyceride change was decreased [ß = - 3.66, 95% CI (- 6.57, - 0.57); P for trend = 0.014]. CONCLUSION: Present study indicates that nutrient patterns may have an association with cardiometabolic factors, particularly a pattern rich in fructose, vitamins A, C, pyridoxine, and potassium which decreases triglyceride level.

Dietary macro- and micro-nutrients intake adequacy at 6th and 12th month post-bariatric surgery.

BACKGROUND: Bariatric surgery (BS) is considered as an effective solution to control morbid obesity. Food restrictions resulting from the operation may decrease dietary nutrient intakes, particularly during the first year after BS. This study mainly aimed to assess the adequacy of dietary nutrient intakes at 6th and 12th month after BS. METHOD: Of the severely obese participants in the Tehran obesity treatment study in 2015-2016, 58 patients undergoing Roux-En-Y gastric bypass (N = 16) or sleeve gastrectomy (N = 42) were selected from Tehran Obesity Treatment Center. To assess the patients' dietary intake, a three-day, 24-h dietary recall was obtained on three unscheduled days (two non-consecutive weekdays and one weekend day) at 6th and 12th month after BS. To evaluate the adequacy of nutrient intake, the patients' intakes were compared to the current dietary reference intakes (DRIs), including estimated average requirements (EAR) or Adequate Intakes (AI). RESULTS: The mean age of the participants (71% women) undergoing BS was 37 ± 8 years. Anthropometric parameters significantly decreased at the 12th month after BS. The percentage of energy from carbohydrate intake increased significantly between the 6th and 12th month after BS (P = 0.04). The mean ± SD of protein intake was lower than the recommended dosage with a dramatic decrease from 45 ± 30 to 31 ± 15 (g/day) between the two intervals (P = 0.001). The mean intake of saturated fatty acid (SFA) decreased dramatically (P < 0.001) from 6 to 12 month; however, the median intake of n3-polyunsaturated fatty acid (n3-PUFA) intake increased (P = 0.02). None of the participants showed nutrient intake adequacy in terms of biotin, fat soluble vitamins, pantothenic acid, potassium, and zinc. Moreover, less than 10% of the participants showed nutrient intake adequacy in terms of folate, magnesium, manganese, and calcium according to DRIs during the both intervals after BS. CONCLUSION: Bariatric surgery can reduce dietary intakes, which is more obvious 12 months after the surgery. Out of 21 micronutrients, nearly all could not met the EAR and were received < 50%, also had significant reduction from the 6th to12th month after surgery.

Red meat and dietary iron intakes are associated with some components of metabolic syndrome: Tehran Lipid and Glucose Study.

BACKGROUND: This study was conducted to investigate whether the daily consumption of haem, non-haem, total iron and red meat can affect the occurrence of metabolic syndrome (MetS) and its components. METHODS: Eligible adults (n = 4654) were selected from among participants of the Tehran Lipid and Glucose Study with an average follow-up of 3.8 years. Dietary intakes were assessed using a valid and reliable semi-quantitative food frequency questionnaire. Anthropometrics and biochemical variables were evaluated at baseline and follow-up examinations. The occurrence of MetS and its components were assessed in relation to haem, non-haem, total iron and red meat intakes. RESULTS: There was no relationship between different types of dietary iron and red meat intakes and the incidence of MetS in the Tehranian population. Risk of hypertension decreased from quartiles 1 to 4 for haem iron (HR: 1.00, 0.92, 0.81, 0.80, Ptrend < 0.01) and red meat intake (HR: 1.00, 0.89, 0.84, 0.77, Ptrend < 0.01). The association between hyperglycemia and the fourth quartile of total iron intake was significant (HR = 1.98, 95% CI 1.08-3.63); and the risk of high triglyceride appeared to increase in higher quartiles of total iron intake (HR: 1.00, 1.17, 1.49, 1.75, Ptrend = 0.01) compared to lower quartiles. CONCLUSION: Our study suggests a potentially protective relationship of haem and moderate red meat intake against development of high blood pressure; and higher intake of total iron is related to hyperglycemia and high triglyceride.

Dietary patterns modify the association between fat mass and obesity-associated genetic variants and changes in obesity phenotypes.

The present study investigated whether dietary patterns could interact with fat mass and obesity-associated (FTO) polymorphisms in relation to changes in BMI and waist circumference (WC) over 3⋅6 years of follow-up. Subjects were selected from participants of the Tehran Lipid and Glucose Study (n 4292, 43⋅2 % male). Dietary data were collected using a valid and reliable FFQ. Dietary patterns were determined using factor analysis. The genotypes of polymorphisms (rs1421085, rs1121980, rs17817449, rs8050136, rs9939973 and rs3751812) were determined. Genetic risk score (GRS) was calculated using the weighted method. Mean ages of men and women were 42·6 (sd 14) and 40⋅4 (sd 13) years, respectively. The healthy (e.g. vegetables and fruits) and the Western dietary patterns (WDP; e.g. soft drinks and fast foods) were extracted. In carriers of the risk alleles rs1121980, rs1421085, rs8050136, rs1781799 and rs3751812, BMI was approximately 2-fold higher in individuals in the higher quartile of WDP score, compared with the first quartile (P < 0⋅05). WC increased with increasing WDP score in carriers of the risk alleles rs1121980 and rs3751812, but not in individuals who did not carry any risk alleles. BMI and WC increased to a greater extent in the high GRS group while increasing quartiles of the WDP score, compared with the low GRS group (BMI change; Q1: 1⋅04 (se 0⋅34) v. Q4: 2⋅26 (se 0⋅36)) (WC change; Q1: 0⋅47 (se 0⋅32) v. Q4: 0⋅95 (se 0⋅34)) (P interaction < 0⋅05). These results suggest that adults with higher genetic predisposition to obesity are more susceptible to the harmful effects of adherence to the WDP, which emphasised the need to reduce the consumption of unhealthy foods for the prevention of obesity.

The association of dietary patterns and adherence to WHO healthy diet with metabolic syndrome in children and adolescents: Tehran lipid and glucose study.

BACKGROUND: The optimal dietary pattern for reducing the extent of metabolic syndrome (MetS) has not been well established yet. The aim of this study was to evaluate dietary patterns and adherence to WHO healthy diet in children and adolescents and their associations with MetS. METHODS: Subjects of this cohort study were selected from among children and adolescents of the Tehran Lipid and Glucose Study participants, aged 6-18 years (n = 424). Dietary measurements were collected using a valid and reliable food frequency questionnaire. MetS was defined as the existence of at least 3 risk factors according to the Cook criteria. Diet was assessed based on dietary components of the WHO healthy diet. Dietary patterns were defined by principal component analysis. RESULTS: The mean ± SD age of participants (42% boys and 57% girls) was 13.5 ± 3.7 years. The most consistency with the WHO healthy diet was observed for cholesterol, free sugar and protein consumption in both genders, and the least was for n-3 poly-unsaturated fatty acid, trans-fatty acid and salt. Intake of SFA up to 12% of energy intake (third quartile) reduced the risk of MetS, compared to the first quartile. Subjects in the third quartile of n-6 poly-unsaturated fatty acid intake (6.2% of energy) showed the lowest odds ratio of MetS compared to the first quartile (OR: 0.18, CI: 0.04-0.66). In the adjusted model, the risk of MetS reduced across quartiles of MUFA intake by 60% (OR: 1, 0.40, 0.40, 0.42; P trend = 0.05). No significant trends were observed in the risk of MetS components across quartiles of the WHO healthy diet components. Three major dietary patterns were identified, the healthy, unhealthy and cereal/meat. An increased risk of MetS was observed in the highest quartile of unhealthy dietary pattern score compared to the lowest quartile (OR: 1, 0.81, 0.93, 2.49; P trend = 0.03). CONCLUSIONS: Our results demonstrated that the majority of our population did not meet some components of WHO healthy diet recommendations. The quality and quantity of fatty acid intakes were associated with risk of MetS. Adherence to unhealthy dietary pattern was associated with two-fold increase in MetS risk.

Low carbohydrate diet is associated with reduced risk of metabolic syndrome in Tehranian adults.

This cohort study was conducted to examine the association of low carbohydrate diet (LCD) score with risk of incident metabolic syndrome (MetS) and its components after 3.6 years of follow-up in 2044 healthy adults within framework of the Tehran Lipid and Glucose Study. The LCD was calculated according to intakes of carbohydrate, monounsaturated fatty acids, refined grains, vegetable protein, fiber, n3/n6 polyunsaturated fatty acids ratio and glycemic load (GL), using a food frequency questionnaire at baseline. In the final model, after adjustment for age, gender, smoking status, physical activity and energy intake, there was significant association between LCD score and fasting plasma glucose (ß: -0.002, 95%CI: -0.005, -0.001), triglycerides (TGs) (ß: -0.002, 95%CI: -0.004, -0.001), BP (ß: -0.001, 95%CI: -0.002, 0.000), WC-BMI (ß: -0.003, 95%CI: -0.005, -0.001) and MetS risk Z-scores (ß: -0.015, 95%CI: -0.021, -0.002). In conclusion, LCD may be associated with a decreased risk of MetS and its components in adults.

Dietary patterns interact with APOA1/APOC3 polymorphisms to alter the risk of the metabolic syndrome: the Tehran Lipid and Glucose Study.

The interaction of genetic and dietary factors, as an area of CVD research, has been explored poorly. The aim of the present study was to examine the interaction of dietary patterns and three genetic variants of APOA1 and APOC3, both independently and in combination, relative to the risk of the metabolic syndrome (MetS) in Tehranian adults. In the present matched, nested case-control study, 414 subjects with the MetS and 414 controls were selected from the participants of the Tehran Lipid and Glucose Study. Dietary patterns were determined by factor analysis. APOC3 (rs5128 3238C>G) and APOA1 (rs670, -75G>A and rs5069,+83C>T) SNP were genotyped by the conventional PCR followed by the restriction fragment length polymorphism technique. Overall, three major dietary patterns were extracted: healthy dietary pattern (HDP); Western dietary pattern (WDP); fat-sweet dietary pattern (FSDP). The A and T allele carriers of the APOA1 SNP had a greater risk of developing the MetS in the highest quartile of WDP scores (OR 3·22, 95 % CI 1·21, 8·58, P(interaction)= 0·03). Compared with other genotype combinations, the combined effect of APOC3/APOA1 (CC/GA+AA/CT+TT) genotypes showed a further increase in the risk of the MetS in the highest quartile of WDP scores (OR 1, 2·49, 8·73, 6·32, P trend< 0·001, P(interaction)= 0·003). A significant interaction was found between the quartiles of FSDP scores and the APOA1 diplotype (GA+AA/CT+TT). OR for these genotype carriers were 1, 0·65, 0·57 and 0·22 (P(trend)= 0·006) in the lowest to the highest quartile of FSDP scores when compared with the other combined genotypes (P(interaction)= 0·03). Our findings suggest that the WDP and FSDP are associated with APOA1 and APOC3 SNP in relation to the risk of the MetS.

Gender differences in the relationship between serum zinc concentration and metabolic syndrome.

BACKGROUND: Zinc, a co-factor of antioxidant enzymes, may be involved in the pathophysiology of metabolic syndrome (MetS). AIM: To determine the association between serum zinc concentration and MetS in a population-based study. SUBJECTS AND METHODS: In the Tehran Lipid and Glucose Study, serum zinc concentration was measured by flame atomic absorption spectrometry in 2626 adult participants. After removal of outliers, usable data was available for 2401 participants. Dietary zinc was assessed by a validated semi-quantitative food frequency questionnaire. RESULTS: Compared to those without the MetS, serum zinc concentration was significantly higher in men with syndrome (17.1 ± 4.9 vs 16.5 ± 4.6 µmol/L, p = 0.035); however, values were comparable in females (16.1 ± 4.8 vs 15.8 ± 4.4, p = 0.460). Men in tertile 3 of serum zinc had significantly higher chances of having MetS, even after multivariate adjustment (OR = 1.48, 95% confidence interval (CI) = 1.07-2.06, p = 0.020). Women in tertile 2 of serum zinc had significantly lower chances of having MetS, which remained significant after multivariate adjustment (OR = 0.68, 95% CI = 0.47-0.99, p = 0.046). CONCLUSION: This study observed a gender difference between serum zinc and MetS, with higher levels being positively associated with MetS in men and having a protective effect in women. Further studies are needed to elucidate the role of zinc status in the development of MetS.

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

BACKGROUND: This study was conducted to assess the prospective association between dietary polyphenols intakes and risk of metabolic syndrome (MetS) and its components. METHODS: 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. RESULTS: 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). CONCLUSION: 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.

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).

AIMS: To evaluate the association between ideal cardiovascular health metrics (ICVHM) and incident low estimated glomerular filtration rate (eGFR) among the Iranian population. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Dietary Intakes of Choline and Betaine and Incidence of Type 2 Diabetes: Tehran Lipid and Glucose Study.

Background: Our knowledge for the possible link between choline and betaine and the risk of type 2 diabetes (T2D) is very limited and contradictory. This study aimed to investigate the prospective association of dietary choline and betaine intakes with the risk of T2D in a group of Tehranian adults. Methods: In this prospective study, 6022 eligible subjects aged ≥18 years were chosen from the participants of the Tehran Lipid and Glucose Study in a secondary analysis. Diet was assessed based on a valid and reliable semiquantitative food frequency questionnaire. At baseline and follow-up examinations, biochemical and anthropometric variables were assessed. Multivariable Cox proportional hazard regression models was used to estimate the new onset of T2D concerning choline and betaine intake. Results: The mean age ± SD of 2707 men and 3315 women were, respectively, 41.4 ± 14.2 and 39.1 ± 13.1. During a median follow-up of 6.63 years, 528 cases of T2D incidence were diagnosed. Participants with a higher intake of choline had a higher intake of protein, fiber, and B12 and a lower intake of energy and carbohydrates. After controlling of confounders a significant positive association was observed between choline intake and the hazard ratio (HR) of T2D across quartiles of choline intake [HR (CI) in the fourth quartile: 1.25 (1.14-1.38), P trend = 0.01], but this significant finding was not reported for betaine intake. For every 100 milligram increase in choline consumption, the HR of T2D increased significantly in all age, sex, and BMI subgroups. Conclusions: Choline consumption increased the risk of T2D in total population and subgroups. No statistically significant association was found between dietary betaine intake and the risk of T2D in total population and subgroups.