Nephrology

Aims:  The aims of the study were to compare the recently evolved Indian Diabetes Risk Score (IDRS), in subjects with different grades of glucose intolerance and to evaluate its usefulness as an indicator of cardiovascular risk in Asian Indians, a high risk group for diabetes and coronary artery disease (CAD).Methods:  The data for the present study were obtained from the Phase 3 (n = 2350, response rate: 90.4%) of the Chennai Urban Rural Epidemiology Study, a population-based study done in Chennai, the largest city in southern India. IDRS was developed based on multiple logistic regression analysis using four simple parameters namely age, abdominal obesity, family history of type 2 diabetes and physical activity. In all subjects, family history of diabetes was obtained, and details on physical activity were assessed using a validated questionnaire. Subjects with an IDRS of <30 was categorized as low risk, 30–50 as medium risk and those with ≥60 as high risk for diabetes. Biochemical and anthropometric measurements were done using standardized procedures. Minnesota coding was used to grade 12-lead electrocardiogram.Results:  The mean IDRS increased significantly with worsening glucose intolerance [normal glucose tolerance (NGT) subjects: 48 ± 17, impaired glucose tolerance (IGT): 57 ± 16, newly diagnosed diabetics (NDD): 61 ± 15 and known diabetics (KD): 68 ± 12; p for trend <0.001]. Among NGT group, the prevalence of cardiovascular risk factors increased progressively in low-, medium- to high-risk score groups; hypertension: 9.4, 22.1 and 38.2% (p for trend: < 0.001), hypertriglyceridemia: 8.8, 19.9 and 25.3% (p for trend: < 0.001), hypercholesterolemia: 7.2, 20.3 and 34.9% (p for trend: < 0.001) and metabolic syndrome: 1.8, 14.6 and 30.3% (p for trend: < 0.001), respectively. The prevalence of CAD was also significantly higher in individuals with high risk compared with those with low risk (p = 0.030) and the medium risk (p = 0.050) in the NGT group.Conclusions:  The results suggest that in Asian Indians, (i) the diabetes risk score increases with increasing glucose intolerance, and (ii) it can serve as an effective indicator of metabolic syndrome and cardiovascular risk even among subjects with NGT.

Aims  The aim of the present study was to assess carotid intimal media thickness (IMT) in different grades of glucose intolerance and the metabolic syndrome (MS) in Asian Indians, a high-risk group for diabetes and coronary artery disease.Methods  Subjects with normal glucose tolerance (NGT) (n = 1600), impaired glucose tolerance (IGT) (n = 330), newly diagnosed diabetes (NDD) (n = 330) and known diabetes (KD) (n = 1170) were recruited from the Chennai Urban Rural Epidemiology Study (CURES), an ongoing study on a representative population of Chennai (formerly Madras), in southern India. Assessment of carotid IMT was performed using high-resolution B-mode ultrasonography. MS was defined using modified adult treatment parel (ATP) III guidelines. Subjects with self-reported diabetes, hypertension and dyslipidaemia were excluded from the analysis on MS.Results  Subjects with glucose intolerance had significantly higher mean carotid IMT values compared with subjects with normal glucose tolerance (NGT 0.69 ± 0.12 mm, IGT 0.75 ± 0.16 mm, NDD 0.79 ± 0.19 mm and KD 0.87 ± 0.24 mm, P < 0.001). Regression analysis showed that there was a linear increase in mean IMT values with increasing severity of glucose intolerance, even after adjusting for age and gender. Mean IMT values were higher in those with MS and increased with increase in number of metabolic abnormalities (subjects without any metabolic abnormality 0.66 ± 0.12 mm, one abnormality 0.67 ± 0.13 mm, two 0.70 ± 0.12 mm, three 0.72 ± 0.12 mm, four 0.77 ± 0.15 mm, five 0.76 ± 0.13 mm). Regression models showed MS to be associated with IMT, even after adjusting for age, gender and presence of diabetes (P = 0.021).Conclusio  In Asian Indians, carotid IMT increases progressively with increasing severity of glucose intolerance and is also associated with the metabolic syndrome, independent of age, gender and presence of diabetes.

Genetic susceptibility may be responsible for high prevalence of type 2 diabetes worldwide. A common missense single nucleotide polymorphism, K121Q in the ectoenzyme nucleotide pyrophosphate phosphodiesterase (ENPP1) gene, has recently been associated with type 2 diabetes in Italian, South Indian, and American populations. The objective of this study was to investigate the possible role of K121Q polymorphism in ENPP1 gene with type 2 diabetes in North Indians. The genotype of the ENPP1/PC-1 K121Q polymorphism was determined using polymerase chain reaction-restriction fragment length polymorphism analysis for 328 T2DM patients and 326 non-diabetic participants. Anthropometric and clinical characteristics (Body mass index (BMI), glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol (HDL), Creatinine, HbA1c, and insulin levels) were measured using standard protocols. Their Chi-square analyses were used to test the significance differences in genotypic and allelic frequencies. Association studies were undertaken using the t test and logistic regression analyses. Our results revealed there was no significant difference in the genotypic distribution between T2DM patients and control subjects. The KK and KQ genotype frequencies were similar in T2DM cases and controls (60.7 and 39.3% in T2DM and 59.8 and 40.2% in controls). No subjects with the QQ genotype were found. Binary logistic regression analysis of data did not show any association of K121Q polymorphism with type 2 diabetes (OR; 0.97, 95% CI; 0.7-1.32, P = 0.82). No significant correlation among the BMI, WHR, BP, TG, TC, HDL-C, LDL-C, Glucose, HbA1c, Creatinine, and insulin indices (HOMA-IR) was observed in the individuals carrying KK and KQ genotypes. In conclusion, our results showed that ENPP1/PC-1 K121Q polymorphism is not associated with type 2 diabetes and related quantitative metabolic traits in North Indian Punjabi population.

India leads the world with largest number of diabetic subjects earning the dubious distinction of being termed the "diabetes capital of the world". According to the Diabetes Atlas 2006 published by the International Diabetes Federation, the number of people with diabetes in India currently around 40.9 million is expected to rise to 69.9 million by 2025 unless urgent preventive steps are taken. The so called "Asian Indian Phenotype" refers to certain unique clinical and biochemical abnormalities in Indians which include increased insulin resistance, greater abdominal adiposity i.e., higher waist circumference despite lower body mass index, lower adiponectin and higher high sensitive C-reactive protein levels. This phenotype makes Asian Indians more prone to diabetes and premature coronary artery disease. At least a part of this is due to genetic factors. However, the primary driver of the epidemic of diabetes is the rapid epidemiological transition associated with changes in dietary patterns and decreased physical activity as evident from the higher prevalence of diabetes in the urban population. Even though the prevalence of microvascular complications of diabetes like retinopathy and nephropathy are comparatively lower in Indians, the prevalence of premature coronary artery disease is much higher in Indians compared to other ethnic groups. The most disturbing trend is the shift in age of onset of diabetes to a younger age in the recent years. This could have long lasting adverse effects on nation's health and economy. Early identification of at-risk individuals using simple screening tools like the Indian Diabetes Risk Score (IDRS) and appropriate lifestyle intervention would greatly help in preventing or postponing the onset of diabetes and thus reducing the burden on the community and the nation as a whole.

To investigate the role of the novel adipokine visfatin in type 2 diabetes mellitus and obesity and to examine its association with visceral and subcutaneous fat in Asian Indians, who have increased susceptibility to type 2 diabetes mellitus and coronary artery disease, 150 subjects with type 2 diabetes mellitus (75 men, 75 women) and 150 age-and sex-matched subjects with normal glucose tolerance were recruited from the Chennai Urban Rural Epidemiology Study, a population-based study done in Chennai, southern India. Anthropometric and biochemical measurements were done by using standardized techniques. Fasting serum visfatin levels were measured by enzyme-linked immunosorbent assay. Visceral and subcutaneous fat were measured by computerized tomography in a subset of 130 individuals. Serum visfatin levels were significantly higher in diabetic subjects compared with nondiabetic subjects (11.4 F 5.9 vs 9.8 F 4.3 ng/mL, P = .008). However, this association was lost when adjusted for body mass index (odds ratio [OR], 1.048; 95% confidence interval [CI], 0.997-1.101; P = .067) or waist circumference (OR, 1.050; 95% CI, 0.999-1.104; P = .057). Serum visfatin showed a significant association with obesity even after adjusting for age, sex, and type 2 diabetes mellitus (OR, 1.060; 95% CI, 1.005-1.119; P = .033). Visceral fat, but not subcutaneous fat, was significantly associated with serum visfatin levels even after adjusting for age, sex, type 2 diabetes mellitus, and body mass index ( P = .002). In Asian Indians, serum visfatin levels are associated with obesity and visceral fat but not with subcutaneous fat. Although visfatin levels are increased in type 2 diabetes mellitus, the association seems to be primarily through obesity. D