Anthropometric Cut-Off Values for Detecting the Presence of Metabolic Syndrome and Its Multiple Components among Adults in Vietnam: The Role of Novel Indices.

Recent studies have shown that using international guidelines to diagnose metabolic syndrome (MetS) may underestimate its prevalence in different Asian populations. This study aims to determine the validity of anthropometric indicators and appropriate cut-off values to predict MetS for Vietnamese adults. We analyzed data on 4701 adults across four regions of Vietnam. Four conventional and five novel anthropometric indexes were calculated. The area under a receiver operating characteristic (ROC) curve (AUC) and Youden's J statistic were applied to evaluate the diagnostic ability and optimal cut-off values. Regardless of diagnostic criteria and gender, Abdominal volume index (AVI), Body roundness index (BRI), and Waist-height ratio (WHtR) had the highest AUC values, followed by Body mass index (BMI) and Waist-hip ratio (WHR). However, it was seen that differences among the AUC values of most indices were minor. In men, using International Diabetes Federation (IDF) criteria, the threshold of indices was 3.86 for BRI, 16.20 for AVI, 0.53 for WHtR, 22.40 for BMI, and 0.90 for WHR. In women, the threshold for these figures were 3.60, 12.80, 0.51, 23.58, and 0.85, respectively. It is recommended that health personnel in Vietnam should apply appropriate thresholds of anthropometry, which are lower than current international guidelines, for MetS screening to avoid under-diagnosis.

Effectiveness of Textured Soybean Protein on Blood Biochemistry in Vietnamese Type 2 Diabetes Mellitus Patients.

Type 2 diabetes mellitus (T2DM) has been increasing rapidly in Vietnam as well as world-wide. One of the major causes of the condition is low fiber intake. It is difficult to eat large amounts of vegetables every day to reach a sufficient amount of fiber but Textured Soybean Protein is rich in fiber. The study aimed to examine the effectiveness of Textured Soybean Protein consumption on T2DM patients. In this randomized controlled trial, 47 T2DM patients were divided into an intervention group (n=24) and a control group (n=23). The intervention group were asked to consume 40 g Textured Soybean Protein in 2 dishes for 4 wk. The control group continued their usual diet. Fasting blood samples were drawn before and after intervention to measure fasting plasma glucose (FPG), fructosamine, low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C), total cholesterol (T-C), and triglycerides (TG). A 3-day food record was conducted at 1 wk before (baseline) and at the last week (final) of the intervention period. In the Textured Soybean Protein consumption group, there was a significant decrease in fructosamine (363±86 µmol/L to 347±82 µmol/L, p=0.03), T-C (5.2±0.9 mmol/L to 4.8±0.8 mmol/L, p=0.02) and TG (3.5±2.2 mmol/L to 2.8±2.0 mmol/L, p=0.02). Total energy intake in the two groups did not change significantly. There was a shift in the dietary pattern of the Textured Soybean Protein consumption group; lipid intake showed a significant decrease (p=0.001) and fiber intake increased by 6 g (p<0.001). The consumption of Textured Soybean Protein in the diet could have favorable effects in improving glycemic and lipid concentrations in T2DM patients.

Initiating BMI prevalence studies in Vietnamese children: changes in a transitional economy.

BACKGROUND: Rapid changes in dietary patterns and lifestyles in Vietnam warrant monitoring trends of weight, height and body mass index (BMI) among children. OBJECTIVE: To determine the trends of weight, height and BMI classification of Vietnamese children, 6-15 years of age, from 1992 to 2000 with reference to socioeconomic, urban and rural differences. METHODS: Data in the Vietnam Living Standard Survey (1992-1993) and the General Nutrition Survey (2000) were collected from representative samples of children. Body mass index classification was determined using the International Obesity Task Force criteria to calculate the prevalence and trends in each survey, and in a pooled survey analysis. RESULTS: Statistically significant increases were seen in children's mean weight, height and BMI between the two surveys: 2.1 kg for weight, 4 cm for height, and 0.28 kg/m2 for BMI. Increases in height were greater in rural than urban areas, and BMI increases were smaller in rural than urban areas. CONCLUSIONS: The rising prevalence of children at risk of overweight in urban Vietnam is a concern that must be monitored to guide policy changes. The unchanging prevalence of rural underweight boys requires attention. A national nutrition program to address under- and overweight for children throughout primary school is needed.

Suitability of instant noodles for iron fortification to combat iron-deficiency anemia among primary schoolchildren in rural Vietnam.

BACKGROUND: Anemia is a significant public health problem among schoolchildren in Vietnam. Food fortification is considered one of the most sustainable long-term strategies to control iron-deficiency anemia in Vietnam. The success of a food-fortification program depends on the choice of the food vehicle. OBJECTIVES: The aim of the present study was to identify an appropriate vehicle for iron fortification to be used in a school-feeding program aimed at improving the iron and anemia status of schoolchildren in rural Vietnam. METHODS: Children 6 to 8 years of age in two primary schools in Tam Nong District, Phu Tho Province, and their parents were included in this study. The study consisted of three substudies: a food-consumption study with 24-hour recalls of two nonconsecutive days; a food-beliefs study, with focus group discussions, a pile-sorting test, and a food attributes and differences exercise; and a food-acceptance study using noodles and biscuits fortified with sodium iron ethylenediaminetetraacetic acid (NaFeEDTA). RESULTS: The average number of meals consumed daily was 3.2 +/- 0.4, and the average intakes of energy and iron were 1,218 +/- 406 kcal and 7.5 +/- 4.0 mg, respectively. Compared with biscuits and instant rice soup, instant noodles were consumed more frequently and in larger portion sizes and are more acceptable as children's food in the culture of the local people. The iron level of the fortified product did not affect the mean consumption of noodles, but a higher level of iron was associated with a lower mean consumption of biscuits (p < .05). The production process did not affect the NaFeEDTA level in noodles; however, during preparation at least 70% of the iron is leaked into the soup. CONCLUSIONS: Instant noodles are a suitable vehicle for iron fortification for use in school-based intervention to improve iron-deficiency anemia among primary schoolchildren in rural Vietnam.

Anemia and intestinal parasite infection in school children in rural Vietnam.

OBJECTIVES: This study hypothesized that besides iron deficiency, intestinal parasites infection is also a determinant of anemia in schoolchildren in rural Vietnam. METHODS: 400 primary schoolchildren from 20 primary schools in Tam Nong district, a poor rural area in Vietnam, were randomly selected from enrollment lists. Venous blood (5ml) was collected in a cross sectional study and analyzed for hemoglobin (Hb), serum ferritin (SF), serum transferrin receptor (TfR), serum C-reactive protein (CRP) and total immunoglobulin E (IgE). Stools samples were examined for hookworm, Trichuris, and Ascaris infection. Logistic regression was used to assess the effect of intestinal parasites on anemia. RESULTS: The prevalence of anemia (Hb < 115g/l) was 25%. Iron deficiency (TfR > 8.5mg/L) occurred in 2% of the children. The prevalence of intestinal parasites was 92% with the highest prevalence for Trichuris (76%) and Ascaris (71%). More than 30% and 80% of the children showed an elevated CRP (> or = 8 mg/L) and IgE (> 90 IU/ml) concentration. Anemia status was borderline significantly associated with SF and not associated with TfR and CRP. The prevalence odds ratio for Trichuris infection was 1.96 (95% CI 1.07-3.59) and 2.00 (95% CI 1.08-3.65) with iron deficiency reflected by TfR and SF, respectively. CONCLUSION: Anemia is highly prevalent among schoolchildren in Vietnam but may not be associated with iron deficiency. Trichuris infection is associated with a doubled risk of anemia, not mediated through iron deficiency. Chronic infection may play a role in anemia, but needs further investigation.

The effect of iron fortification and de-worming on anaemia and iron status of Vietnamese schoolchildren.

Previous data from Vietnam show that anaemia is highly prevalent among schoolchildren, who are considered not to be iron deficient. Trichuris infection doubled the risk of anaemia. The present study aimed to evaluate the hypothesis that de-worming is more effective than iron fortification in an anaemic, infection-prone population. In a trial with a 2 x 2 factorial design, 425 anaemic children aged 6-8 years were randomly assigned to receive either iron-fortified noodles or placebo, and mebendazole or placebo. Outcomes considered were change in haematological indicators of iron status (Hb, serum ferritin (SF), serum transferrin receptor (TfR) and haemoglobinopathies analysis); inflammations (C-reactive protein (CRP)); parasite infection status (hookworm, Trichuris and Ascaris infection); and IgE. ANOVA and logistic regression were used to assess the effects of iron fortification and de-worming on Hb, SF, TfR, body iron and anaemia. Hb improved in all groups after 6 months of intervention. Iron fortification significantly improved Hb, SF and body iron (2.6 g/l, 16.3 microg/l and 1 mg/kg, respectively). Prevalence of elevated IgE was very high at baseline (99%) and significantly reduced to about 75% in all groups after intervention. De-worming unexpectedly showed no effect on Hb, iron status and IgE level. It is concluded that iron fortification slightly improved anaemia and iron status in anaemic schoolchildren in rural Vietnam that were not considered iron deficient. Chronic infection or other unidentified factors may play an important role in the seasonal reduction of anaemia seen in all treatment groups.

Efficacy of iron fortification compared to iron supplementation among Vietnamese schoolchildren.

The effect of iron fortification is generally assumed to be less than iron supplementation; however, the magnitude of difference in effects is not known. The present study aims to compare the efficacy of these two strategies on anaemia and iron status. After screening on low Hb, 425 anaemic children in six primary schools in Tam Nong district of Phu Tho province were included in a randomized, placebo-controlled trial comparing two groups receiving iron fortified instant noodles or iron supplementation for 6 months and a control group, with children in all groups having been dewormed. Blood samples were collected before and after intervention for haemoglobin, serum ferritin (SF), serum transferrin receptor (TfR), C-reactive protein (CRP), and haemoglobinopathies analysis. Regression analysis was used to assess the effect of iron fortification and iron supplementation on haemoglobin concentration, SF, TfR, body iron, and anaemic status as outcome variables. The improvement of haemoglobin, SF, and body iron level in the group receiving iron fortification was 42% (2.6 g/L versus 6.2 g/L), 20% (23.5 microg/L versus 117.3 microg/L), and 31.3% (1.4 mg/kg versus 4.4 mg/kg) of that in the iron supplementation group. The prevalence of anaemia dropped to 15.1% in the control group, with an additional reduction of anaemia of 8.5% in the iron supplementation group. The additional reduction due to iron fortification was 5.4%, which amounts to well over 50% of the impact of supplementation. In conclusion, the efficacy of iron fortification based on reduction of prevalence of anaemia, and on the change in haemoglobin level, is about half of the maximum impact of supplementation in case of optimal compliance. Thus, in a population of anaemic children with mild iron deficiency, iron fortification should be the preferred strategy to combat anaemia.