A population-based prospective study on obesity-related non-communicable diseases in northern Iran: rationale, study design, and baseline analysis.

Background: Iran is facing an epidemiological transition with the increasing burden of non-communicable diseases, such as obesity-related disorders and cardiovascular diseases (CVDs). We conducted a population-based prospective study to assess the prevalence and incidence rates of CVDs and obesity-related metabolic disorders and to evaluate the predictive ability of various CVD risk assessment tools in an Iranian population. Method: We enrolled 5,799 participants in Amol, a city in northern Iran, in 2009-2010 and carried out the first repeated measurement (RM) after seven years (2016-2017). For all participants, demographic, anthropometric, laboratory, hepatobiliary imaging, and electrocardiography data have been collected in the enrollment and the RM. After enrollment, all participants have been and will be followed up annually for 20 years, both actively and passively. Results: We adopted a multidisciplinary approach to overcome barriers to participation and achieved a 7-year follow-up success rate of 93.0% with an active follow-up of 5,394 participants aged 18-90 years. In the RM, about 64.0% of men and 81.2% of women were obese or overweight. In 2017, about 16.2% and 5.2% of men had moderate or severe non-alcoholic fatty liver disease, while women had a significantly higher prevalence of metabolic syndrome (35.9%), and type 2 diabetes mellitus (20.9%) than men. Of 160 deceased participants, 69 cases (43.1%) died due to CVDs over seven years. Conclusion: The most prevalent obesity-related chronic disease in the study was metabolic syndrome. Across the enrollment and RM phases, women exhibited a higher prevalence of obesity-related metabolic disorders. Focusing on obesity-related metabolic disorders in a population not represented previously and a multidisciplinary approach for enrolling and following up were the strengths of this study. The study outcomes offer an evidence base for future research and inform policies regarding non-communicable diseases in northern Iran.

The association between dietary inflammatory index (DII) scores and c-reactive protein (CRP) and nonalcoholic fatty liver disease (NAFLD) in a general population cohort.

BACKGROUND AND AIMS: Although there is extensive literature showing the ability of the dietary inflammation index (DII®) to predict concentrations of plasma inflammatory markers, few studies are testing the association between DII scores and nonalcoholic fatty liver disease (NAFLD). Considering the high prevalence of NAFLD and its complications, we conducted a validation study of DII scores and examined its association with NAFLD in the general adult population of Iran. METHODS: This cross-sectional study was conducted on 3110 adult participants in the Amol Cohort Study (AmolCS) who underwent abdominal ultrasonography to diagnose NAFLD. DII and energy-adjusted DII (E-DII™) scores were computed using data from a valid semi-quantitative 168-item food frequency questionnaire (FFQ). Multivariable logistic regression adjusting for socio-demographic, lifestyle, and health-related factors was used to assess association. RESULTS: The EDII was associated with CRP inflammatory biomarker. Participants in the highest, i.e., most pro-inflammatory tertile had the highest odds of NAFLD by ultrasound in all models [fully adjusted model: OR (95 % CI) tertile3vs.1:1.54 (1.05-2.05); Ptrend = 0.04, and 1.63 (1.19-2.21); Ptrend = 0.03 in women and men, respectively]. The highest tertile had the highest OR for NAFLD by fatty liver index (FLI) only in men [fully adjusted model OR (95 % CI) tertile3vs.1: 1.77 (1.15-2.71); Ptrend = 0.01]. Similar results were also obtained for NAFLD by hepatic steatosis index (HSI) in women [fully adjusted model: OR (95 % CI) tertile3vs.1: 1.70 (1.12-2.58); Ptrend = 0.03]. The results of the fully adjusted multivariable model of liver markers and NAFLD status, stratified by gender and abdominal obesity, revealed that the highest tertiles had the highest OR for NAFLD by ultrasound and NAFLD by FLI only in men without abdominal obesity [fully adjusted model: OR (95 % CI) tertile3vs.1: 1.83 (1.17-2.84); Ptrend = 0.03, and, respectively]. NAFLD by FLI tended to increase strongly with tertile E-DII scores in men without abdominal obesity in crude and three adjusted models [full-adjusted model: OR (95 % CI) tertile3vs.1: 3.64 (1.56-8.46); Ptrend = 0.005]. By contrast, women with abdominal obesity in the highest tertile had the highest OR for NAFLD by ultrasound in all models [full-adjusted model: OR (95 % CI) tertile3vs.1: 1.67 (1.07-2.62); Ptrend = 0.02]. CONCLUSIONS: Our results suggest that diet plays a role in regulating inflammation. Additionally, we observed an inflammatory diet predicts the risk of NAFLD in Iranian adults. However, longitudinal studies are required in order to further substantiate the utility of the DII in the development of more effective dietary interventions among populations at risk of chronic disease.

The effect of folic acid supplementation on body weight and body mass index: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND OBJECTIVE: Several trials have evaluated the effects of folate supplementation on obesity indices. However, their results were inconsistent. Therefore, the current meta-analysis was conducted to summarize data from available randomized clinical trials (RCTs) about the impact of folate supplementation on weight and body mass index (BMI). METHOD: Medline/PubMed, Scopus, Embase, and ISI web of science were searched to identify relevant articles up to December 2020. The effect sizes were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI) using the random-effects model. RESULTS: Pooled data from nine studies showed that folic acid supplementation did not change body weight (WMD: -0.16 kg, 95%CI: -0.47 to 0.16, P = 0.32) and BMI (WMD: -0.23 kg/m2, 95%CI: -0.49 to 0.03, P = 0.31), but there was significant heterogeneity between the included studies for BMI (I2 = 90.1%, P < 0.001). Moreover, subgroup analyses in level of homocysteine and health status indicated significant effect of folic acid supplementation on BMI in those with homocysteine level ≥15 µmol/L (WMD: -0.17 kg/cm2, -0.33 to -0.01, p = 0.03) and in women with polycystic ovary syndrome (PCOS) (WMD: - 0.30kg/cm2, -0.54 to -0.06, p = 0.01). CONCLUSION: Our outcomes demonstrated that folic acid improves BMI in those with homocysteine levels ≥15 µmol/L and women with PCOS.

Mediators of dietary diversity score (DDS) on NAFLD in Iranian adults: a structural equation modeling study.

BACKGROUND: The current study examines the association between the Dietary Diversity Score (DDS) and nonalcoholic fatty liver disease (NAFLD) in Iranian adults using structural equation modeling (SEM). METHODS: A sample of 3220 adults from the Amol Cohort Study was recruited for this cross-sectional study. Dietary acid load (DAL) and DDS were calculated using the data obtained from a validated food frequency questionnaire. Anthropometric parameters, blood pressure, biochemical measurements, and liver ultrasonography were evaluated according to standard protocols. RESULTS: DDS was neither directly nor indirectly associated with a greater prevalence of NAFLD. In the second model (DDS sub-scores model), the association of DAL with NAFLD was fully mediated through waist circumference (WC) (of DAL to WC: ß = 0.14, P < 0.0001, and of WC to NAFLD: ß = 0.50, P < 0.001). Vegetable and fruit diversity scores had a significant negative indirect relationship with NAFLD prevalence through DAL (ß = -0.06, P = 0.001, ß = -0.10, P < 0.001, respectively). Meat diversity score was positively associated with NAFLD prevalence in a full mediational process through DAL (ß = 0.12, P < 0.001). The SEM fit indices suggested a reasonably adequate fit of the data to the DDS model (Χ2/df = 4.76, GFI = 0.98, AGFI = 0.97, IFI = 0.97, CFI = 0.97, RMSEA = 0.03, and SRMR = 0.02) and its sub-scores model (Χ2/df = 4.72, GFI = 0.98, AGFI = 0.97, IFI = 0.95, CFI = 0.95, RMSEA = 0.03, and SRMR = 0.02). CONCLUSION: Meat diversity and lack of vegetable and fruit diversity were indirectly associated with NAFLD prevalence through DAL and WC mediators. Interventions for NAFLD may be more successful if they target a lower intake of animal protein sources and dietary diversity, particularly vegetable and fruit diversity.

Dietary Acid Load (DAL), Glycated Hemoglobin A1c (HbA1c), and Metabolic Syndrome (MeS) Mediate the Association of the Adherence to the Dietary Approaches to Stopping Hypertension (DASH) and Mediterranean Diet (MeD) With Nonalcoholic Fatty Liver Disease.

The study aimed to investigate the association of adults adhering to Dietary Approaches to Stop Hypertension (DASH) and Mediterranean diet (MeD) with nonalcoholic fatty liver disease (NAFLD) using structural equation modeling (SEM) in Iran. In this population-based cross-sectional study, 3,220 adults (44.65% female) aged ≥18 years were selected from the Amol Cohort Study (AmolCS). The dietary intakes were assessed by a validated 168-item semi-quantitative food-frequency questionnaire (FFQ). Residual method energy adjustment of MeD and DASH scores were calculated. Demographic characteristics and anthropometric and laboratory measurements were collected. NAFLD was diagnosed by an expert radiologist via ultrasound sonography. Based on the primary hypothesis, DASH, MeD, and NAFLD were fitted into models. Metabolic syndrome (MeS) as a potential risk factor directly affected NAFLD risk in all these models. In both genders, the higher adherence to DASH negatively affected NAFLD risk indirectly through the two following paths. (1) Dietary acid load (DAL) and metabolic syndrome (2) DAL and hemoglobin A1c (HbA1c). In addition, the higher DAL positively affected NAFLD risk among male participants indirectly via increasing HbA1c level and MeS (from DAL to HbA1c: ß = 0.07, P < 0.001; from HbA1c to MeS: ß = 0.10, P < 0.001). Similarly, in both genders, the relationship between MeD and NAFLD was mediated through (1) DAL, HbA1c, and MeS and (2) DAL and MeS. Further, among male participants, the MeD and NAFLD risk were also associated via the mediators of HbA1c and MeS. In female participants, the higher MeD score was directly associated with a reduction of NAFLD risk (ß = -0.07, P = 0.008). The present study found three important mediators, including DAL, HbA1c, and MeS, in the association of DASH and MeD scores with NAFLD risk. Preventive and therapeutic interventions should target the mediators, including DAL, HbA1c, MeS, and its components, to reduce NAFLD incidence in the general population.

Scoring systems of metabolic syndrome and prediction of cardiovascular events: A population based cohort study.

BACKGROUND AND AIMS: Continuous scoring systems were developed versus traditional dichotomous approaches to define metabolic syndrome. The current study was carried out to evaluate the ability of scoring systems to predict fatal and nonfatal cardiovascular events. MATERIALS AND METHODS: The data of 5147 individuals aged 18 years or more obtained from a population-based cohort study were analyzed. The occurrence of atherosclerotic cardiovascular disease (ASCVD) in the period of 7 years follow-up was considered as the associated outcome. Joint Interim Statement (JIS) definition, as a traditional definition of metabolic syndrome (MetS), and two versions of MetS scoring systems, based on standardized regression weights from structural equation modeling (SEM) and simple method for quantifying metabolic syndrome (siMS) were considered as potential predictors. RESULTS: The scoring systems, particularly, based on SEM, were observed to have a significant association with composite cardiovascular events (HR = 1.388 [95% CI = 1.153-1.670], p = .001 in men and HR = 1.307 [0.95% CI = 1.120-1.526] in women) in multiple Cox proportional hazard regression analyses, whereas the traditional definition of MetS did not show any significant association. While both two scoring systems showed acceptable predictive abilities for cardiovascular events in women (MetS score based on SEM: area of under curve [AUC] = 0.7438 [95% CI = 0.6195-0.7903] and siMS: AUC = 0.7207 [95% CI = 0.6676-0.7738]), the two systems were not acceptable for identifying risk in men. CONCLUSION: Unlike the dichotomous definition of MetS, the scoring systems showed an independent association with cardiovascular events. Scoring systems, particularly those based on SEM, may be useful for the prediction of cardiovascular events in women.

The Relationship between Functional Constipation and Major Dietary Patterns in Iranian Adults: Findings from the Large Cross-Sectional Population-Based SEPAHAN Study.

Although associations between dietary patterns and risk of chronic conditions have recently received increased attention, few studies have examined the relationship between major dietary patterns and risk of constipation. We collected dietary data using a validated dish-based, 106-item semi-quantitative Food Frequency Questionnaire on 4,763 adults aged 18∼55 years. Data on anthropometric measures were collected through self-administered questionnaires. Functional constipation was defined based on the Iranian validated version of Rome III. Factor analysis followed by a varimax rotation was applied to derive major dietary patterns from 39 predefined food groups, and logistic regression was used for association analysis. Three major dietary patterns were extracted: traditional (TD), fruit and vegetables dominant (FVD), and Western (WD). The association between TD and constipation was not significant for both genders and for the total sample. However, in the crude model and the fully adjusted model, poor adherence to the FVD was associated with a higher risk of constipation in men and in the total sample. In addition, we observed a significantly lower risk of constipation in the total sample and in female participants with low adherence to WD; however, this was not significant for male participants. Further studies in other populations, and future prospective studies, are required to reiterate these results.

Relationship between dietary macronutrient composition and non-alcoholic fatty liver disease in lean and non-lean populations: a cross-sectional study.

OBJECTIVE: The current study aimed to customize dietary changes for lean patients with non-alcoholic fatty liver disease (NAFLD). DESIGN: The current study was done with a population-based cross-sectional design. The FFQ was used to analyse dietary macronutrient intake and ultrasonography results for NAFLD diagnosis. The study subjects were divided into the lean and non-lean groups based on their BMI (< 25 and ≥ 25). Multivariable logistic regression was used to evaluate the relationship between dietary macronutrients and NAFLD. Substitution analyses were also performed. SETTING: Amol and its suburban areas in Iran. PARTICIPANTS: Adults in the age range of 18 to < 65 with full relevant data. RESULTS: Among the total study subjects (2308), 46·7 % had fatty liver. The substitution of polysaccharides for animal protein and SFA in the lean group resulted in a significant NAFLD reduction, whereas the substitution of SFA for all types of macronutrients, except for n-6 and mono-disaccharides, led to a significant increase in NAFLD (P < 0·05). In non-lean participants, the substitution of MUFA for mono-disaccharides resulted in a significant reduction of NAFLD (P < 0·05). In this group, the substitution of SFA and mono-disaccharides for MUFA, and n-6 for all macronutrients, except vegetable protein and SFA, were significantly related to an increase in NAFLD (P < 0·05). CONCLUSIONS: Lower lean NAFLD is correlated with increasing polysaccharides in exchange for SFA and animal protein intake, whereas lower non-lean NAFLD is correlated with increasing MUFA in exchange for mono-disaccharides and reducing n-6 and SFA.

The association between dietary pattern and coronary artery disease: A case-control study.

Introduction: Dietary patterns are an important factors in the progress of cardiovascular disease. This study aimed to assess the association between dietary patterns and coronary artery disease (CAD). Methods: A case-control study was carried on 550 participants. Food expenditure was collected using a validated 168-item food-frequency questionnaire. Dietary patterns were extracted by principal component analysis (PCA). Multiple logistic regressions was used to assess the association between dietary patterns and the risk of CAD. Results: Three major dietary patterns were identified: the "Quasi-Western Pattern" was characterized by higher intakes of sweets and desserts, snacks, legumes, honey or jam, ketchup, mayonnaise, yellow vegetables, potatoes, red meat, refined grains; the "Sugar and Fast foods Pattern" was characterized by higher intakes of sugar, soft drinks, fast foods, high-fat dairy, hydrogenated fats, and the "Quasi-Mediterranean Pattern" was characterized by higher intakes of fruits, cruciferous vegetables, green leafy vegetables, other vegetables, nuts, coffee. In both sexes, the "Quasi-Western Pattern" and the "Sugar and Fast foods Pattern" were positively associated with the risk of CAD. For "Quasi-Western Pattern", adjusted-ORs were (OR: 1.35, 95% CI: 0.99-1.83, P = 0.05) and (OR: 1.38, 95% CI: 1.03-1.83, P = 0.03)for men and women respectively. The ORs were for "Sugar and Fast foods Pattern" (OR: 3.64, 95% CI:2.25-5.89, P < 0.001) and (OR: 3.91, 95% CI: 2.42-6.63, P < 0.001) for men and women respectively.There was a significant inverse relationship among "Quasi-Mediterranean pattern" and CAD in the crude model in women (OR: 0.7, 95% CI: 0.55-0.89, P = 0.0.004). Conclusion: High adherence to the "Quasi-Western Pattern" and "Sugar-Fast foods Pattern" dietary patterns were associated with a higher risk of CAD. The "Quasi-Mediterranean pattern" reduced the risk of CAD.