Sargoor R. Veena

FTO gene variants are strongly associated with type 2 diabetes in South Asian Indians

Aims and hypothesisVariants of the FTO (fat mass and obesity associated) gene are associated with obesity and type 2 diabetes in white Europeans, but these associations are not consistent in Asians. A recent study in Asian Indian Sikhs showed an association with type 2 diabetes that did not seem to be mediated through BMI. We studied the association of FTO variants with type 2 diabetes and measures of obesity in South Asian Indians in Pune.MethodsWe genotyped, by sequencing, two single nucleotide polymorphisms, rs9939609 and rs7191344, in the FTO gene in 1,453 type 2 diabetes patients and 1,361 controls from Pune, Western India and a further 961 population-based individuals from Mysore, South India.ResultsWe observed a strong association of the minor allele A at rs9939609 with type 2 diabetes (OR per allele 1.26; 95% CI 1.13–1.40; p = 3 × 10−5). The variant was also associated with BMI but this association appeared to be weaker (0.06 SDs; 95% CI 0.01–0.10) than the previously reported effect in Europeans (0.10 SDs; 95% CI 0.09–0.12; heterogeneity p = 0.06). Unlike in the Europeans, the association with type 2 diabetes remained significant after adjusting for BMI (OR per allele for type 2 diabetes 1.21; 95% CI 1.06–1.37; p = 4.0 × 10−3), and also for waist circumference and other anthropometric variables.ConclusionsOur study replicates the strong association of FTO variants with type 2 diabetes and similar to the study in North Indians Sikhs, shows that this association may not be entirely mediated through BMI. This could imply underlying differences between Indians and Europeans in the mechanisms linking body size with type 2 diabetes.

Intrauterine exposure to maternal diabetes is associated with higher adiposity and insulin resistance and clustering of cardiovascular risk markers in Indian children

OBJECTIVE To test the hypothesis that maternal gestational diabetes increases cardiovascular risk markers in Indian children. RESEARCH DESIGN AND METHODS Anthropometry, blood pressure, and glucose/insulin concentrations were measured in 514 children at 5 and 9.5 years of age (35 offspring of diabetic mothers [ODMs], 39 offspring of diabetic fathers [ODFs]). Children of nondiabetic parents were control subjects. RESULTS At age 9.5 years, female ODMs had larger skinfolds (P < 0.001), higher glucose (30 min) and insulin concentrations, and higher homeostasis model assessment (HOMA) of insulin resistance and systolic blood pressure (P < 0.05) than control subjects. Male ODMs had higher HOMA (P < 0.01). Associations were stronger than at age 5 years. Female ODFs had larger skinfolds and male ODFs had higher HOMA (P < 0.05) than control subjects; associations were weaker than for ODMs. Associations between outcomes in control subjects and parental BMI, glucose, and insulin concentrations were similar for mothers and fathers. CONCLUSIONS The intrauterine environment experienced by ODMs increases diabetes and cardiovascular risk over genetic factors; the effects strengthen during childhood.

Cortisol and the metabolic syndrome in South Asians

objective The cardiovascular risk factors which comprise the metabolic syndrome are associated with increased hypothalamic–pituitary–adrenal axis (HPAA) activity in some Caucasian populations. South Asians have high rates of cardiovascular disease and its risk factors. We have investigated the relationships between HPAA activity, adiposity and the metabolic syndrome in a South Asian population.

Maternal vitamin D status during pregnancy and body composition and cardiovascular risk markers in Indian children: the Mysore Parthenon Study–

BACKGROUND Metabolic consequences of vitamin D deficiency have become a recent research focus. Maternal vitamin D status is thought to influence musculoskeletal health in children, but its relation with offspring metabolic risk is not known. OBJECTIVE We aimed to examine the association between maternal vitamin D status and anthropometric variables, body composition, and cardiovascular risk markers in Indian children. DESIGN Serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured at 28-32 wk gestation in 568 women who delivered at Holdsworth Memorial Hospital, Mysore, India. Anthropometric variables, glucose and insulin concentrations, blood pressure, and fasting lipid concentrations were measured in the offspring at 5 and 9.5 y of age. Muscle-grip strength was measured by using a hand-held dynamometer at age 9.5 y. Arm-muscle area was calculated as a measure of muscle mass. Fasting insulin resistance was calculated by using the homeostasis model assessment equation. RESULTS Sixty-seven percent of women had vitamin D deficiency [serum 25(OH)D concentration <50 nmol/L]. At ages 5 and 9.5 y, children born to vitamin D-deficient mothers had smaller arm-muscle area in comparison with children born to mothers without deficiency (P < 0.05). There was no difference in grip strength between offspring of women with and without vitamin D deficiency. At 9.5 y, children of vitamin D-deficient mothers had higher fasting insulin resistance than did children of nondeficient women (P = 0.04). There were no associations between maternal vitamin D status and other offspring risk factors at either age. CONCLUSION Intrauterine exposure to low 25(OH)D concentrations is associated with less muscle mass and higher insulin resistance in children.

Maternal homocysteine in pregnancy and offspring birthweight: epidemiological associations and Mendelian randomization analysis

BACKGROUND Disturbed one-carbon (1-C) metabolism in the mother is associated with poor fetal growth but causality of this relationship has not been established. METHODS We studied the association between maternal total homocysteine and offspring birthweight in the Pune Maternal Nutrition Study (PMNS, Pune, India) and Parthenon Cohort Study (Mysore, India). We tested for evidence of causality within a Mendelian randomization framework, using a methylenetetrahydrofolatereductase (MTHFR) gene variant rs1801133 (earlier known as 677C→T) by instrumental variable and triangulation analysis, separately and using meta-analysis. RESULTS Median (IQR) homocysteine concentration and mean (SD) birthweight were 8.6 µmol/l (6.7,10.8) and 2642 g (379) in the PMNS and 6.0 µmol/l (5.1,7.1) and 2871 g (443) in the Parthenon study. Offspring birthweight was inversely related to maternal homocysteine concentration-PMNS: -22 g/SD [95% confidence interval (CI): (-50, 5), adjusted for gestational age and offspring gender]; Parthenon: -57 g (-92, -21); meta-analysis: -40 g (-62, -17)]. Maternal risk genotype at rs1801133 predicted higher homocysteine concentration [PMNS: 0.30 SD/allele (0.14, 0.46); Parthenon: 0.21 SD (0.02, 0.40); meta-analysis: 0.26 SD (0.14, 0.39)]; and lower birthweight [PMNS: -46 g (-102, 11, adjusted for gestational age, offspring gender and rs1801133 genotype); Parthenon: -78 g (-170, 15); meta-analysis: -61 g (-111, -10)]. Instrumental variable and triangulation analysis supported a causal association between maternal homocysteine concentration and offspring birthweight. CONCLUSIONS Our findings suggest a causal role for maternal homocysteine (1-C metabolism) in fetal growth. Reducing maternal homocysteine concentrations may improve fetal growth.

Breastfeeding duration, age of starting solids and high BMI risk and adiposity in Indian children

This study utilized data from a prospective birth cohort study on 568 Indian children, to determine whether a longer duration of breastfeeding and later introduction of solid feeding were associated with a reduced higher body mass index (BMI) and less adiposity. Main outcomes were high BMI (>90th within-cohort sex-specific BMI percentile) and sum of skinfold thickness (triceps and subscapular) at age 5. Main exposures were breastfeeding (six categories from 1-4 to ≥21 months) and age of starting regular solid feeding (four categories from ≤3 to ≥6 months). Data on infant-feeding practices, socio-economic and maternal factors were collected by questionnaire. Birthweight, maternal and child anthropometry were measured. Multiple regression analysis that accounted for potential confounders demonstrated a small magnitude of effect for breastfeeding duration or introduction of solid feeds on the risk of high BMI but not for lower skinfold thickness. Breastfeeding duration was strongly negatively associated with weight gain (0-2 years) [adjusted β = -0.12 standard deviation, 95% confidence interval (CI): -0.19 to -0.05 per category change in breastfeeding duration, P = 0.001], and weight gain (0-2 years) was strongly associated with high BMI at 5 years (adjusted odds ratio = 3.8, 95% CI: 2.53-5.56, P < 0.001). In our sample, findings suggest that longer breastfeeding duration and later introduction of solids has a small reduction on later high BMI risk and a negligible effect on skinfold thickness. However, accounting for sampling variability, these findings cannot exclude the possibility of no effect at the population level.

Adiposity, insulin resistance and cardiovascular risk factors in 9–10-year-old Indian children: relationships with birth size and postnatal growth

Lower birthweight, and rapid childhood weight gain predict elevated cardiovascular risk factors in children. We examined associations between serial, detailed, anthropometric measurements from birth to 9.5 years of age and cardiovascular risk markers in Indian children. Children (n = 663) born at the Holdsworth Memorial Hospital, Mysore, India were measured at birth and 6-12 monthly thereafter. At 9.5 years, 539 (255 boys) underwent a 2-h oral glucose tolerance test, and blood pressure (BP) and fasting lipid concentrations were measured. Insulin resistance was calculated using the HOMA equation. These outcomes were examined in relation to birth measurements and changes in measurements (growth) during infancy (0-2 years), 2-5 years and 5-9.5 years using conditional s.d. scores. Larger current weight, height and skinfold thickness were associated with higher risk markers at 9.5 years (P < 0.05). Lower weight, smaller length and mid-arm circumference at birth were associated with higher fasting glucose concentrations at 9.5 years (P ⩽ 0.01). After adjusting for current weight/height, there were inverse associations between birthweight and/or length and insulin concentrations, HOMA, systolic and diastolic BP and plasma triglycerides (P < 0.05). Increases in conditional weight and height between 0-2, 2-5 and 5-9.5 years were associated with higher insulin concentrations, HOMA and systolic BP. In conclusion, in 9-10-year-old Indian children, as in other studies, cardiovascular risk factors were highest in children who were light or short at birth but heavy or tall at 9 years. Greater infant and childhood weight and height gain were associated with higher risk markers.

Prediction of body-fat percentage from skinfold and bio-impedance measurements in Indian school children

Background/Objectives:Few equations for calculating body-fat percentage (BF%) from field methods have been developed in South-Asian children. The objective of this study was to assess agreement between BF% derived from primary reference methods and that from skinfold equations and bio-impedance analysis (BIA) in Indian children.Subjects/Methods:We measured BF% in two groups of Indian children. In Pune, 570 rural children aged 6–8 years underwent dual-energy X-ray absorptiometry (DXA) scans. In Mysore 18O in doubly labeled water was administered to 59 urban children aged 7–9 years. We conducted BIA at 50 kHz and anthropometry, including sub-scapular and triceps skinfold thicknesses. We used the published equations of Wickramasinghe, Shaikh, Slaughter and Dezenburg to calculate BF% from anthropometric data and the manufacturers equation for BIA measurements. We assessed agreement with values derived from DXA and doubly labeled water using Bland–Altman analysis.Results:Children were light and thin on average compared with international standards. There was poor agreement between the reference BF% values and those from all equations. Assumptions for Bland–Altman analysis were not met for Wickramasinghe, Shaikh and Slaughter equations. The Dezenberg equations under-predicted BF% for most children (mean difference in Pune −13.4, LOA −22.7, −4.0 and in Mysore −7.9, LOA (−13.7 and −2.2). The mean bias for the BIA equation in Pune was +5.0% and in Mysore +1.95%, and the limits of agreement were wide; −5.0, 15.0 and –7.8, 11.7 respectively.Conclusions:Currently available skinfold equations do not accurately predict BF% in Indian children. We recommend development of BIA equations in this population using a four-compartment model.

Placental programming of blood pressure in Indian children

Aim:  To determine whether the size and shape of the placental surface predict blood pressure in childhood.

Diet patterns are associated with demographic factors and nutritional status in south Indian children

Abstract The burden of non‐communicable chronic disease (NCD) in India is increasing. Diet and body composition ‘track’ from childhood into adult life and contribute to the development of risk factors for NCD. Little is known about the diet patterns of Indian children. We aimed to identify diet patterns and study associations with body composition and socio‐demographic factors in the Mysore Parthenon Study cohort. We collected anthropometric and demographic data from children aged 9.5 years (n = 538). We also administered a food frequency questionnaire and measured fasting blood concentrations of folate and vitamin B12. Using principal component analysis, we identified two diet patterns. The ‘snack and fruit’ pattern was characterised by frequent intakes of snacks, fruit, sweetened drinks, rice and meat dishes and leavened breads. The ‘lacto‐vegetarian’ pattern was characterised by frequent intakes of finger millet, vegetarian rice dishes, yoghurt, vegetable dishes and infrequent meat consumption. Adherence to the ‘snack and fruit’ pattern was associated with season, being Muslim and urban dwelling. Adherence to the lacto‐vegetarian pattern was associated with being Hindu, rural dwelling and a lower maternal body mass index. The ‘snack and fruit’ pattern was negatively associated with the childs adiposity. The lacto‐vegetarian pattern was positively associated with blood folate concentration and negatively with vitamin B12 concentration. This study provides new information on correlates of diet patterns in Indian children and how diet relates to nutritional status. Follow‐up of these children will be important to determine the role of these differences in diet in the development of risk factors for NCD including body composition.