Marked gender difference in plasma total homocysteine concentrations in indian adults with low vitamin B12.

CONTEXT: Plasma total homocysteine (tHcy) is higher in men than women. OBJECTIVE: To explore the gender differences in tHcy in relation to determinants of one-carbon metabolism in Indian people with low B12 and adequate folate. SETTING: The study took place in rural and urban areas of Pune, India. DESIGN AND PARTICIPANTS: Participants were 441 men from the cross-sectional Coronary Risk of Insulin Sensitivity in Indian Subjects study (CRISIS) and premenopausal wives of 146 men (median ages 38 and 34 years, respectively). MAIN OUTCOME MEASURES: Gender difference in fasting tHcy in relation to plasma albumin and creatinine concentrations, lifestyle factors, diet and lean mass, plasma B12 and red cell folate (RCF) was assessed. RESULTS: Prevalence of high tHcy (> 15 µmol/L, median 14.4 µM) was 40 %, low B12 (< 150 pmol/L, 114 pmol/L) 66 %, and low RCF (< 283 nmol/L, 525 nmol/L) 8 %. Men had higher (1.8x) plasma tHcy concentrations (16.2 µmol/L) than women (9.5 µmol/L). Only 50 % of the gender difference was explained by age, lean mass, B12, and RCF. The difference remained after controlling for other explanatory variables. Women with a tHcy of 9.3 µM had the same B12 concentration (129 pmol/L) as men with a tHcy of 15 µM; and for a tHcy of 10.0 µmol/L women had the same RCF concentration (533 nmol/L) as men with a tHcy of 15 µmol/L. CONCLUSIONS: Adult Indian women have markedly lower tHcy concentrations compared to men. This suggests a lower threshold for supplementation to improve reproductive and cardiovascular outcomes.

Vitamin B12 deficiency and hyperhomocysteinemia in rural and urban Indians.

BACKGROUND: Low vitamin B12 concentration in South Asian Indians is common, but the exact prevalence is not known. AIM: To investigate prevalence and associations of low vitamin B12 concentration and hyperhomocysteinemia in rural and urban Indian men living in and around Pune, Maharashtra. METHOD: We studied 441 middle-aged men (149 rural, 142 slum and 150 urban middle-class residents, mean age 39 y). Data on lifestyle, socio-economic status, nutrition and medical history were obtained. Circulating concentrations of vitamin B12, folate, ferritin, total homocysteine (tHcy), and haematological indices, and cardiovascular risk variables were measured. RESULTS: Median plasma B12 concentration was low (110 pmol/L): Overall, 67% of men had low vitamin B12 concentration (<150 pmol/L) and 58% had hyperhomocysteinemia (>15 micromol/L). Of the urban middle class, 81% had low vitamin B12 concentration and 79% had hyperhomocysteinemia. Low vitamin B12 concentration contributed 28% to the risk of hyperhomocysteinemia (population attributable risk) while low red cell folate contributed 2%. Vegetarians had 4.4 times (95% CI 2.1, 9.4) higher risk of low vitamin B12 concentrations and 3.0 times (95% CI 1.4, 6.5) higher risk of hyperhomocysteinemia compared to those who ate non-vegetarian foods frequently. Urban middle-class residence was an additional independent risk factor of hyperhomocysteinemia (odds ratio 7.6 (95% CI 2.5, 22.6), compared to rural men). Low vitamin B12 concentration was related to lower blood haemoglobin concentration and higher mean corpuscular volume, but macrocytic anemia was rare. CONCLUSION: Low vitamin B12 concentration and hyperhomocysteinemia are common in Indian men, particularly in vegetarians and urban middle class residents. Further studies are needed to confirm these findings in other parts of India.

Body fat and cardiovascular risk factors in Indian men in three geographical locations.

We studied cardiovascular risk factors in 149 rural, 142 slum dwellers, and 150 urban middle class Indian men (30 to 50 years, mean 40 years) in relation to their body fat. Mean body mass index (BMI) was 21.0, 22.3, and 24.3 kg/m2 and mean body fat percent (bioimpedance) was 20.4, 22.5, and 30.4, respectively. A 75 g oral glucose tolerance test showed no diabetes in rural subjects; 4% of urban slum dwellers and 10% of urban middle class men were diabetic. Hypertension (blood pressure > or = 140/90 mm Hg) was present in 2% of the rural, 4% of the urban slum, and 10% of the urban middle class men. All cardiovascular risk factors were strongly related the percentage of body fat and waist to hip ratio. Two hour plasma glucose concentration and blood pressure were, in addition, independently related to geographical location (urban middle class were higher than slums who were higher than rural men). Our results suggest that urbanization increases the risk of hyperglycemia and hypertension independent of the percentage of body fat or its central distribution.

Associations of trunk fat depots with insulin resistance, ß cell function and glycaemia--a multiple technique study.

OBJECTIVE: Central (truncal) adiposity is associated strongly with insulin resistance and diabetes. There are very few reports comparing methods of trunk fat measurement in their ability to predict glycaemia and insulin resistance. We report a comparative analysis of different trunk fat measurements in predicting glycaemia and insulin resistance in middle aged Indian men. MATERIALS AND METHODS: Trunk fat measurements were performed using anthropometry, magnetic resonance imaging (MRI), dual-energy X-ray absorptiometry (DXA) and computed tomography (CT) on 128 men. Additional measurements were taken to characterise insulin resistance (Matsuda index) and beta cell function (Insulinogenic Index), glycaemia (fasting and 120 min glucose concentrations). Using residual approach we compared the ability of different trunk fat measurement techniques to predict insulin resistance, beta cell function and glycaemia. RESULTS: There was a strong association between trunk fat measures from each technique with glycaemia and insulin resistance indices but not with the Insulinogenic Index. Insulin resistance and glycaemia, were best predicted using anthropometric measurements, notably by waist circumference and subscapular skinfold thickness. Neither MRI measures of trunk or visceral fat nor DXA trunk fat added significantly. CT liver density contributed to some extent to predict insulin resistance and 120 min glucose after anthropometric measurements. CONCLUSIONS: Our results suggest that, in Indian men, anthropometric measurements are good predictors of glycaemia and insulin resistance. Other complex measurements such as MRI, DXA and CT make only a small addition to the prediction. This finding supports the application of anthropometry for determining trunk fat in clinical and epidemiological settings.

Increasing maternal parity predicts neonatal adiposity: Pune Maternal Nutrition Study.

OBJECTIVE: This study was undertaken to study the effect of parity on maternal and neonatal characteristics. STUDY DESIGN: Maternal anthropometry, diet, micronutrient status, biochemistry, and physical activity were measured during pregnancy and detailed neonatal size recorded in 770 pregnancies in rural Maharashtra, India. RESULTS: Increasing parity was associated with larger offspring birth weight, skinfold thicknesses, and abdominal circumference, but not head circumference and length. Compared with primiparous women, multiparous women were older, less adipose, and more physically active but had similar education, socioeconomic status, nutritional intake, and weight gain during pregnancy. They had lower circulating concentrations of hemoglobin, albumin, ferritin, glucose, and insulin and lower total leucocyte counts at 18 and 28 weeks' gestation. There was no difference in their husbands' body size. The relationship between maternal parity and neonatal weight and adiposity was significant independent of the difference in maternal characteristics. CONCLUSION: Increasing maternal parity predicts increasing adiposity in the newborn infant. This may result from maternal nutritional, cardiovascular, or immunologic factors.