Iranian Journal of

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Background: Risk factors of cardiovascular disorders have been the subject of several studies. Recently, simultaneous high waist circumference (WC) and high serum triglyceride (Tg) has been proposed as a simple screening measure to predict non-traditional risk factors. This study has looked at the risk factors of cardiovascular disorders present in subjects with this phenotype.
Methods: Non diabetic females of age 18-65 years who had been enrolled in the Tehran Lipid and Glucose Study (TLGS) were recruited. Based on fasting Tg and WC, subjects fell into four categories: TgHWH ( Tg>160 mg/dl, WC>80 cm), TgHWL (Tg>160 mg/dl,WC<80 cm), TgLWH(Tg<160 mg/dl,WC>80 cm) and TgLWL (Tg<160 mg/dl,WC<80 cm). Cardiovascular risk factors including lipid profiles and anthropometric variables were compared between the categories. The prevalence of hypertension, LDL-C>130 mg/dl, total cholesterol>220 mg/dl and HDL- C<45 mg/dl were also determined in each category.
Results: 5630 subjects were studied. TgLWL and TgHWH constituted to 27.5 % and 31.9 % of subjects, respectively. Mean age of subjects dropping in TgLWL, TgLWH, TgHWL and TgHWH groups was 28±10, 39±12, 36+12 and 46±11, respectively and TgHWH subjects were significantly older than other groups (p<.001). Systolic and diastolic blood pressures, body mass index and WC were significantly higher in TgHWH. Significantly higher levels of total cholesterol, triglycerides and LDL-C and significantly lower level of HDL-C were found in the TgHWH group. The prevalence of subjects with four or more risk factors was 61.4% in TgHWH versus 1% in TgLWL group.
Conclusion: Parallel high waist circumference and high serum triglycerides (TgHWH) can find use as a simple screening measure to predict other risk factors of cardiovascular disorders.

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Background:Obesity is a serious public health problem in developing countries due to its association with the cardiovascular risk factors. Childhood obesity is responsible for a number of different complications both during childhood and adulthood. The aim of the present study was to determine the cardiovascular risk factors in overweight and obese Iranian children.
Methods: We screened 13086 children aged 7-12 years by measuring waist circumference. Those with a waist circumference ≥61 cm were selected for further evaluation. Anthropometric measurements were done and blood samples were taken from 563 enrolled overweight/obese children (284 boys and 279 girls). We determined cardiovascular risk factors (including fasting total cholesterol, LDL-C, HDL-C, triglycerides, blood pressure). In addition we measured the fasting blood sugar, insulin, apo-A , apo-B and leptin levels.
Results: Only 2.7% of overweight or obese children had no risk factors. While, 20.6% had one and 70.85% had two or more risk factors. The prevalence of high total Cholestrol levels was 42.6%. HDL-C showed an acceptable level in 92.4%of children .There were strong correlations between BMI and serum apoB and leptin levels (p<0.005).
Conclusion: The high prevalence of cardiovascular risk factors in overweight and obese Iranian children emphasizes the need for prevention and control of childhood obesity from early childhood in our country.

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Background: Prevalence of obesity is increasing globally , and it is proved that obesity is associated with cordiovascular diseases, type II diabetes, hypertension, dyslipidemia and breast cancer. This study was carried out among 150 female students of Shadid Beheshti university who were resided in Velekjad dormitory, in order to assess the rate of obesity among them .
Methods: As a cross-sectional study height, weight, waist circumference and hip circumference were measured . Food frequency and socioeconomic questionnairs were completed . BMI and WHR were used to assess the general and central obesity respectively.
Results: Mean standard deviation of age, BMI, WHR, WC were 260 31 (months), 21.42 2.56 (kg/m2), 0.79 0.04 and 75.71 7.10 (cm) respectively. Among subjects , 40.5% had WHR more than 0.8 , 9.3% were overweight, 62.1% normal and 28.6% underweight. Of whom, 37.8% weren't exercising at all. There was a negative correlation between BMI and consumption of butter , milk , meat (p<0.001 for all) and egg ( p<0.01) ,between WHR and consumption of egg and butter (p<0.01 for both of them) and also between WC and cosumption of butter (P<0.001) and milk (P<0.01).
Conclusion: Although prevalence of general obesity among the subjects was low, central obesity (based on WHR) was significant, so lifestyle modifications such as nutritional changes and increase physical activity among students is recommended.

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Background: The aim of this study was to determine the best Anthropometric indices for prediction of the risk of type 2 Diabetes in lower and higher 60 years old population in Tehran.
Methods: As a prospective study among 4479 non-diabetic men and women over 20 years from the participants of Tehran Lipid and Glucose Study (TLGS) who had complete data of blood pressure, plasma glucose in the fasting state and 2 hours after ingestion of 75 g glucose (2-hPG) as well as fasting serum lipids, anthropometric measurement including body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR) and demographic data at baseline and were followed for a mean duration of 3.6 years. Subjects reevaluated for measurement of fasting Glucose and 2-hPG at follow-up. Diabetes and its associated risk factors were defined according to the ADA criteria. Different measurements of general and central obesity were defined based on the WHO criteria. Logistic regression analysis with stepwise conditional method was used to estimate the Odds Ratio (OR) with 95% CI. Results: A total of 166 new cases of type 2 diabetes (3.7%) were diagnosed during 3.6 years of follow-up, with an approximately one percent per year incidence rate (men=3.7% and women =3.7%, P= 0.95). Diabetic subjects of follow-up were significantly more obese than nondiabetics considering their BMI, WC and WHR. In subjects aged< 60 years high WC was a predictor of diabetes only in model 1 and 2, while general obesity and high WHR predicted diabetes risk in all the 3 models. In these 3 models the OR of general obesity were 5.3(2.9-9.5), 3.4(1.8-6.3), 2.4(1.1-5.1) and the OR of high WHR were 3.5(2.1-5.8), 3.4(1.4-5.8) and 2.6(1.3-4.9), respectively. In subjects aged≥ 60 years general obesity predicted diabetes only in models 1 and 2, while high WHR was a predictor of diabetes risk only in model 1. In this age group, high WC predicted diabetes in all models 1, 2, 3 with the OR of 4.6 (2.3-4.1), 4.5 (2.3-8.9) and 3.8 (1.8-7.7), respectively.
Conclusion: General obesity and high WHR in young Iranian subjects (< 60years) and high WC in older ones (≥ 60 years) are the important anthropometric indices for prediction of type 2 diabetes. Age should be considered when using different anthropometric indices for predicting the risk of type 2 diabetes.

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Background: Evidences exist that abdominal obesity is a difference in terms of body mass index (BMI) and these two factors have different effects on bone density. This study examined the association between body mass index, obesity, the history of fracture and bone mineral density in Iranian population. There exist evidences on the effects of body mass index (BMI) and abdominal obesity, and the role of this two factor on bone density. This study examined the association between body mass index, abdominal obesity, and the frequency of fracture with bone mineral density in Iranian population Methods: The Study was done as a cross-sectional, population-based retrospective study. People over 18 years were included in the third part of the IMOS project (National comprehensive plan for the prevention, diagnosis and treatment of osteoporosis). Abdominal obesity was calculated based on waist to hip ratio that was considered positive > 0.95 in men and 0.85 in women. The linear regression test was used to examine the relationship between BMI and abdominal obesity with bone densitometry. Results: A total 2019 cases (717 men, 1302 women) with 41.85 ± 13.95 years enrolled in this study. Almost, 36% of men and women were obese based on waist circumference. Correlation coefficients of BMI with bone density were equal 0.236 for Hip, 0.133 for femoral neck, 0.138 for lumbar spine. Waist to hip ratio was inversely associated with bone density. Bone densities in the hip and lumbar spine, in individuals with a positive history of wrist fracture were significantly lower than those with a negative history of fracture. Conclusion: contrary to the total body fat, abdominal obesity based on waist to hip ratio is inversely associated with bone density. In other words, abdominal obesity increases the risk of fractures by reducing the bone density without creating protective shield of adipose tissue in vulnerable areas.

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Background: Although the relation of serum vitamin D levels with abdominal obesity has been investigated by previous observational studies, the results are inconsistent. In the current study, a dose-response meta-analysis was conducted on epidemiologic studies that evaluated this association in adults.
Methods: We performed a systematic search of all published articles, up to May 2020, in five electronic databases. A total of 41 observational studies that reported odds ratios (ORs) or relative risks (RRs) with 95% confidence intervals (CIs) for abdominal obesity in relation to serum vitamin D levels in adults were found.
Results: Meta-analysis on 36 cross-sectional studies (combining 44 effect sizes) with 257699 participants, illustrated that the highest serum vitamin D level in comparison with the lowest serum vitamin D level was significantly related to 23% decreased odds of central obesity (OR=0.77; 95%CI:0.71-0.83). This inverse association was also significant in almost all subgroups based on different covariates. Based on dose-response analysis, each 25 nmol/l increase in serum vitamin D levels, was related to 8% reduced risk of central obesity (OR=0.92;95%CI:0.85,0.99). After limiting the analysis to 23 effect sizes from 17 studies with representative population (242135 participants), the same results were obtained (OR=0.79; 95%CI: 0.71-0.87). Based on dose-response analysis on studies with representative populations, each 25 nmol/l increase in blood vitamin D levels was linked to 10% decreased central adiposity risk(OR=0.90; 95%CI: 0.82, 0.99).
Conclusion: In this meta-analysis of epidemiologic studies, we demonstrated an inverse significant relation between serum vitamin D levels and risk of central obesity in adults, in a dose-response manner. The same findings were obtained in representative populations.