Understanding the predictive accuracy of the InsuTAG index over other surrogate indices in normoglycaemic, non-obese males from Southern India.

We aimed to evaluate the predictive accuracy of InsuTAG index against M value of the hyperinsulinaemic-Euglycaemic clamp (HEC) procedure and fasting surrogate indices of insulin sensitivity/resistance in young, normoglycaemic, Asian Indian males. HEC studies were done in young (mean age 19.7 ± 1 years), non-obese (mean BMI 19.2 ± 2.6 kg/m2), normoglycemic Asian Indian males (n = 110) and the M value was calculated. Surrogate indices namely InsuTAG index, HOMA-IR, FG-IR, QUICKI and McAuley index were calculated. Pearson's correlation and ROC-AUC at 95% CI were applied. Significant negative correlation was observed for InsuTAG index with the M value (r - 0.23, p = 0.01), McAuley index (r - 0.65, p < 0.01), QUICKI (r - 0.34, p < 0.01) and FGIR (r - 0.35, p < 0.01). Significant positive correlations of InsuTAG index were observed for BMI and waist circumference. The ROC-AUC was higher for InsuTAG index (0.75) than FGIR (0.30), QUICKI (0.31), and McAuley index (0.20). The InsuTAG cut-off value ≥ 19.13 showed 66.7% sensitivity and 69.2% specificity in this study group.

The triglyceride/glucose ratio is a reliable index of fasting insulin resistance: Observations from hyperinsulinaemic-euglycaemic clamp studies in young, normoglycaemic males from southern India.

BACKGROUND & AIMS: Non-obese Asians have a high propensity to develop insulin resistance. Therefore, screening such individuals for insulin resistance using simple surrogate indices is important. In this study, we aimed to validate the triglyceride-glucose (Tg/glu) ratio against the M value of hyperinsulinaemic-euglycaemic clamp (HEC) procedure and other surrogate indices of insulin resistance in normoglycaemic Indian males from Southern India. METHODS: A cohort of 105 normoglycaemic males (mean BMI: 19.2 ± 2.6 kg/m2) underwent HEC procedure. Surrogate indices of insulin resistance viz. the triglyceride-glucose (Tg/Glu) ratio, the triglyceride-glucose index, the McAuley's index, the HOMA-IR, the QUICKI, the fasting glucose to insulin ratio (FG-IR), and the fasting C- peptide index were calculated and correlated with the M value. The cut-off value for the Tg/Glu ratio was obtained using the Receiver Operator Characteristics (ROC) with Area under curve (AUC) analysis at 95% confidence interval (CI). The P value < 0.05 was considered statistically significant. RESULTS: The Tg/Glu ratio demonstrated significantly higher AUC (0.81), when compared to the Tg × glu index (0.63), 20/fasting C peptide × fasting plasma glucose index (0.55), HOMA-IR (0.47), QUICKI (0.26), FGIR (0.12) and McAuley's index (0.18). For the Tg/Glu ratio, a cut-off value ≥ 1.19 had high sensitivity (80%) and specificity (79%) values (PPV: 16%; NPV: 98.8%) respectively. CONCLUSION: The Tg/Glu ratio can be used as a reliable surrogate index to screen for risk of insulin resistance in lean, normoglycaemic males from Southern India.

Challenges in Implementation of ANISA Protocol at the Vellore Site, India.

BACKGROUND: The Aetiology of Neonatal Infection in South Asia (ANISA) study aims to determine the population-based incidence, etiology, risk factors and antibiotic resistance profiles of community-acquired young infant infections in Bangladesh, India and Pakistan using community-based surveillance and standard newer diagnostic tests. The data generated will help plan preventive and treatment strategies to reduce neonatal and infant mortality in this region. The aim of this article is to describe the site-specific characteristics, challenges and solutions in implementing the ANISA protocol at the Vellore site, India. CHALLENGES: Vellore joined the ANISA study 2 years after the sites in Bangladesh and Pakistan, and some challenges relate to the need for rapid implementation. The Vellore site differs primarily in the high rate of institutional deliveries, actively promoted by the Government of India's conditional cash transfer program. The Vellore site hospitals are regular care providers for the study population, which leads to very high rates of consent for enrollment and collection of samples. Keeping blood culture contamination rates low was a challenge the site team overcame by adhering strictly to the protocol. Issues related to incorporation of a large study into a busy clinical services laboratory were overcome by meticulously setting up algorithms related to receipt, processing and storage of samples. CONCLUSION: ANISA is a complex study, but the challenges in implementation have been largely resolved and documented.

Born with low birth weight in rural Southern India: what are the metabolic consequences 20 years later?

OBJECTIVE: Low birth weight (LBW) is common in the Indian population and may represent an important predisposing factor for type 2 diabetes (T2D) and the metabolic syndrome. Intensive metabolic examinations in ethnic LBW Asian Indians have been almost exclusively performed in immigrants living outside India. Therefore, we aimed to study the metabolic impact of being born with LBW in a rural non-migrant Indian population. SUBJECTS AND METHODS: One hundred and seventeen non-migrant, young healthy men were recruited from a birth cohort in a rural part of south India. The subjects comprised 61 LBW and 56 normal birth weight (NBW) men, with NBW men acting as controls. Subjects underwent a hyperinsulinaemic euglycaemic clamp, i.v. and oral glucose tolerance tests and a dual-energy X-ray absorptiometry scan. The parents' anthropometric status and metabolic parameters were assessed. RESULTS: Men with LBW were shorter (167±6.4 vs 172±6.0 cm, P<0.0001), lighter (51.9±9 vs 55.4±7 kg, P=0.02) and had a reduced lean body mass (42.1±5.4 vs 45.0±4.5 kg, P=0.002) compared with NBW controls. After adjustment for height and weight, the LBW subjects had increased diastolic blood pressure (77±6 vs 75±6 mmHg, P=0.01). Five LBW subjects had impaired glucose tolerance. In vivo insulin secretion and peripheral insulin action were similar in both the groups. Mothers of the LBW subjects were 3 cm shorter than the control mothers. CONCLUSION: Only subtle features of the metabolic syndrome and changes in body composition among LBW rural Indians were found. Whether other factors such as urbanisation and ageing may unmask more severe metabolic abnormalities may require a long-term follow-up.