Adipocytokines and the expanding 'Asian Indian Phenotype'

This article does not have an abstract

The Chennai Urban Rural Epidemiology Study (CURES) - study design and methodology (Urban Component) (CURES - 1)

The report of World Health Organization (WHO) shows that India tops the world with the largest number of diabetic subjects. This increase is attributed to the rapid epidemiological transition accompanied by urbanization, which is occurring in India. There is very little data regarding the influence of affluence on the prevalence of diabetes and its complications particularly retinopathy in the Indian population. Furthermore, there are very few studies comparing the urban / rural prevalence of diabetes and its complications. The Chennai Urban Rural Epidemiology Study (CURES) is designed to answer the above questions. CURES is initially planned as a cross-sectional study to evolve later into a longitudinal study. Subjects for the urban component of the CURES have been recruited from within the corporation limits of Chennai City. Chennai (formerly Madras), the largest city in Southern India and the fourth largest in India has been divided into 10 zones and 155 wards. 46 wards were selected by a systematic random sampling method to represent the whole of Chennai. Twenty thousand and one individuals were recruited for the study, this number being derived based on a sample size calculation. The study has three phases. Phase one is a door to door survey which includes a questionnaire, anthropometric, fasting capillary blood glucose and blood pressure measurements. Phase two focussed on the prevalence of diabetic complications particularly retinopathy using standardized techniques like retinal photography etc. Diabetic subjects identified in phase one and age and sex matched non-diabetic subjects will participate in these studies. Phase three will include more detailed studies like clinical, biochemical and vascular studies on a sub-sample of the study subjects selected on a stratified basis from phase one. CURES is perhaps one of the largest systematic population based studies to be done in India in the field of diabetes and its complications like retinopathy, nephropathy and neuropathy

Incidence of Diabetes and Pre-diabetes in a Selected Urban South Indian Population (Cups - 19)

Abstract Objectives: Several cross-sectional studies have reported on the prevalence of diabetes in India. However, there are virtually no longitudinal population-based studies on the incidence of diabetes from India. The aim of the study was to determine the incidence of diabetes and prediabetes in an urban south Indian population. Methods: The Chennai Urban Population Study [CUPS], an ongoing epidemiological study in two residential colonies in Chennai [the largest city in southern India, formerly called Madras] was launched in 1996; the baseline study was completed in 1997. Follow-up examination was performed after a mean period of 8 years. At follow-up, 501 [47.0%] subjects had moved out of this colonies and were lost to follow-up. Of the remaining 564 individuals, 513 [90.9%] provided blood samples for biochemical analysis. Regression analysis was done using incident diabetes as dependant variable to identify factors associated with development of diabetes or pre-diabetes. Results: Among subjects with normal glucose tolerance (NGT) at baseline [n=476], 64 (13.4%) developed diabetes and 48 (10.1%) developed pre-diabetes (IGT or IFG). The incidence rate of diabetes was 20.2 per 1000 person years and that of pre-diabetes was 13.1 per 1000 person years among subjects with NGT. Of the 37 individuals who were pre-diabetic at baseline, 15 (40.5%) developed diabetes [incidence rate: 64.8 per 1000 person years], 16 (43.2%) remained as pre-diabetic and 6 (16.2%) reverted to normal during the follow-up period. Regression analysis revealed obesity [Odds Ratio (OR): 2.1, p=0.001], abdominal obesity [OR: 2.23, p<0.001] and hypertension [OR: 2.57, p<0.001] to be significantly associated with incident diabetes. The Indian Diabetes Risk Score (IDRS) showed the strongest association with incident diabetes [OR: 5.14, p<0.001]. Conclusion: The study shows that the incidence of diabetes is very high among urban south Indians. While obesity, abdominal obesity and hypertension were associated with incident diabetes, IDRS was th

Prevalence, Awareness and Control of Hypertension in Chennai - The Chennai Urban Rural Epidemiology Study (CURES – 52)

Objective : To study the prevalence, awareness and control of hypertension in Chennai representing Urban South India. Methods : The Chennai Urban Rural Epidemiology Study (CURES) is one of the largest epidemiological studies on diabetes carried out in India, where 26,001 individuals aged ≥ 20 years were screened using systematic random sampling method. Every tenth subject recruited in Phase 1 of CURES was requested to participate in Phase 3 of CURES and the response rate was 2,350/26,001 or 90.4%. An oral glucose tolerance test was performed in all individuals except self-reported diabetic subjects. Anthropometric measurements and lipid estimations were done in all subjects. Hypertension was diagnosed in all subjects who were on drug treatment for hypertension or if the blood pressure ≥ 140/90 mmHg. Results : Hypertension was present in 20% [men:23.2% vs. women:17.1%, p<0.001] of the study population. Isolated systolic hypertension (Systolic BP ≥ 140 and Diastolic BP<90 mmHg) was present in 6.6% while isolated diastolic hypertension (DBP ≥ 90 and SBP<140 mmHg) was present in 4.2% of the population. Among the elderly population (aged ≥ 60 years), 25.2% had isolated systolic hypertension. Age, body mass index, smoking, serum cholesterol and triglycerides were found to be strongly associated with hypertension. Among the total hypertensive subjects, only 32.8% were aware of their blood pressure, of these, 70.8% were under treatment and 45.9% had their blood pressure under control. Conclusion : Hypertension was present in one-fifth of this urban south Indian population and isolated systolic hypertension was more common among elderly population. Majority of hypertensive subjects still remain undetected and the control of hypertension is also inadequate. This calls for urgent prevention and control measures for hypertensio

A simplified Indian diabetes risk score for screening for undiagnosed diabetic subjects

Aim: The aim of this study was to develop and validate a simplified Indian Diabetes Risk Score for detecting undiagnosed diabetes in India. Methods: The risk score was derived from the Chennai Urban Rural Epidemiology Study (CURES), an ongoing epidemiological study on a representative population of Chennai. Phase 1 of CURES recruited 26,001 individuals, of whom every tenth subject was requested to participate in Phase 3 for screening for diabetes using World Health Organization (WHO) 2hour venous plasma glucose criteria [i.e. ≥200 mg/dl]. The response rate was 90.4% (2350/2600). The Indian Diabetes Risk Score [IDRS] was developed based on results of multiple logistic regression analysis. Internal validation was performed on the same data. Results: IDRS used four risk factors: age, abdominal obesity, family history of diabetes and physical activity. Beta co-efficients were derived based on a multiple logistic regression analysis using undiagnosed diabetes as the dependent variable. The beta co-efficients were modified so as to obtain a maximum possible score of 100. Receiver Operating Characteristic [ROC] curves were constructed to identify the optimum value of IDRS for detecting diabetes by WHO consulting group criteria. Area under the curve for ROC was 0.698 (95% confidence interval (CI):0.663 .0.733). An IDRS value . 60 had the optimum sensitivity (72.5%) and specificity (60.1%) for determining undiagnosed diabetes with a positive predictive value of 17.0%, negative predictive value of 95.1%, and accuracy of 61.3%. Conclusion: This simplified Indian Diabetes Risk Score is useful for identifying undiagnosed diabetic subjects in India and could make screening programmes more cost effective

Association of Small Dense LDL with Coronary Artery Disease and Diabetes in Urban Asian Indians - The Chennai Urban Rural Epidemiology Study (CURES-8)

Objective: Earlier studies in Europeans have identified small dense LDL to be associated with coronary artery disease and diabetes. In this study we assessed the association of small dense LDL with diabetes and CAD in Asian Indians. Methods: Study subjects were selected from the Chennai Urban Rural Epidemiology Study (CURES), a population based study on representative sample of Chennai city in southern India. Group 1:non-diabetic subjects (n=30); Group 2: diabetic subjects without CAD (n=30); Group 3:diabetic subjects with CAD (n=30). LDL subfractions were estimated using LipoPrint LDL system. LDL subfractions 3 and above, defined as small dense LDL was summed up to determine the overall small LDL. 75th percentile of the overall small dense LDL in non-diabetic subjects was used as a cut-off for defining elevated levels of small dense LDL. Results: The mean age of the study subjects was not significantly different among groups. Overall small dense LDL was significantly higher in diabetic subjects with CAD (16.7 ± 11.1 mg/dl, p<0.05) and without CAD (11.1 ± 8.0 mg/dl, p<0.05) compared to non-diabetic subjects without CAD (7.2 ± 6.8 mg/dl). Small dense LDL showed a positive correlation with fasting plasma glucose (r=0.252, p=0.023), HbA1c (r=0.281, p=0.012), total cholesterol (r=0.443, p<0.001), triglycerides(r=0.685, p<0.001), LDL(r=0.342, p=0.002), total cholesterol/HDL ratio (r=0.660, p=<0.001) and triglycerides/HDL ratio(r=0.728, p<0.001) and a negative correlation with HDL cholesterol (r= -0.341, p=0.002) and QUICKI values (r= -0.260, p=0.019). ROC curves constructed to predict elevated small dense LDL ((9.0 mg/dl) revealed that triglycerides/HDL ratio and total cholesterol/HDL ratio had higher AUC values compared to other parameters. A triglycerides/HDL ratio of 3.0 had the optimum sensitivity (80.0%) and specificity (78.0%) for detecting elevated small dense LDL. Conclusion: This data suggests that in Asian Indians, small dense LDL is associated with both diabetes and CAD and that a triglycerides/HDL ratio (3.0 could serve a surrogate marker of small dense LDL

Prevalence and Risk Factors of Diabetic Nephropathy in an Urban South Indian Population: The Chennai Urban Rural Epidemiology Study (CURES 45)

OBJECTIVE— The aim of this study was to determine the prevalence of diabetic nephropathy among urban Asian-Indian type 2 diabetic subjects. RESEARCH DESIGN AND METHODS— Type 2 diabetic subjects (n 1,716), inclusive of known diabetic subjects (KD subjects) (1,363 of 1,529; response rate 89.1%) and randomly selected newly diagnosed diabetic subjects (NDD subjects) (n 353) were selected from the Chennai Urban Rural Epidemiology Study (CURES). Microalbuminuria was estimated by immunoturbidometric assay and diagnosed if albumin excretion was between 30 and 299 g/mg of creatinine, and overt nephropathy was diagnosed if albumin excretion was 300 g/mg of creatinine in the presence of diabetic retinopathy, which was assessed by stereoscopic retinal color photography. RESULTS— The prevalence of overt nephropathy was 2.2% (95% CI 1.51–2.91). Microalbuminuria was present in 26.9% (24.8 –28.9). Compared with the NDD subjects, KD subjects had greater prevalence rates of both microalbuminuria with retinopathy and overt nephropathy (8.4 vs. 1.4%, P 0.001; and 2.6 vs. 0.8%, P 0.043, respectively). Logistic regression analysis showed that A1C (odds ratio 1.325 [95% CI 1.256 –1.399], P 0.001), smoking (odds ratio 1.464, P0.011), duration of diabetes (1.023, P0.046), systolic blood pressure (1.020, P 0.001), and diastolic blood pressure (1.016, P0.022) were associated with microalbuminuria. A1C (1.483, P 0.0001), duration of diabetes (1.073, P 0.003), and systolic blood pressure (1.031, P 0.004) were associated with overt nephropathy. CONCLUSIONS— The results of the study suggest that in urban Asian Indians, the prevalence of overt nephropathy and microalbuminuria was 2.2 and 26.9%, respectively. Duration of diabetes, A1C, and systolic blood pressure were the common risk factors for overt nephropathy and microalbuminuria

Diabetes-social and economic perspectives in the new Millenium

Prevalence of diabetes is increasing in pandemic proportions, particularly in developing countries like India. The recent reports from the World Health Organization rates India as the country with the largest number of diabetic subjects in the world. The Chennai Urban Population Study (CUPS), The Chennai Urban Rural Epidemiology Study (CURES) and the National Urban Diabetes Survey (NUDS) revealed rising prevalence of diabetes in India. Some of the significant risk factors associated with diabetes are similar worldwide, but their intensities vary between races, regions and countries. The reason for escalation of diabetes prevalence in India could be attributed to a combination of genetic factors and environmental factors due to urbanization and industrialization, which has led to sedentary lifestyle, physical inactivity, stress and obesity arising from energy and fat rich diets. The long-term complications of diabetes occurring during the most productive years of their lives create a devastating burden of morbidity and mortality, which poses an economic and social burden both at the individual and at the national level. Compared to non-diabetic individuals, diabetic individuals are more than twice as costly to treat, mainly due to the high costs related with management of associated complications. Prevention seems to be the need of the hour to tackle this epidemic. This article highlights the social and economic implications of diabetes in India and emphasis the measures required to prevent diabetes

Mortality rates due to diabetes in a selected Urban South Indian population - the Chennai Urban Population Study [CUPS - 16]

Objective: The aim of this study was to determine the mortality rate in diabetic and non-diabetic subjects in urban south India. Methods: The Chennai Urban Population Study is an ongoing epidemiological study in Chennai [formerly Madras, in south India]. All individuals . 20 years of age living in two residential colonies in Chennai were invited to participate in the study. Of the total 1399 eligible subjects, 1262 individuals responded [90.2%] at baseline, and of these, 1140 individuals [90.3%] could be followed annually from 1997 to 2003-04. Mortality rates and causes of death were the main outcome measures. Results: The median follow up period was six years. The overall mortality rate was higher in diabetic compared to non-diabetic subjects [18.9 vs.5.3 per 1000 person-years, p=0.004]. Mortality due to cardiovascular [diabetic subjects, 52.9%; non-diabetic subjects, 24.2%,p=0.042] and renal causes[diabetic subjects, 23.5%; non-diabetic subjects, 6.1%,p=0.072] was higher among diabetic subjects whereas mortality due to gastrointestinal [12.1%], respiratory [9.1%], lifestyle related [6.1%] and unnatural causes [18.2%] were observed only among non-diabetic subjects. Hazards ratio [HR] for all cause mortality for diabetes was 3.6, [95% Confidence Interval [CI]: 2.02-6.53, p&lt;0.001] and this remained significant even after adjusting for age [HR:1.9, 95% CI:1.04-3.45, p=0.038]. Light grade physical activity was associated with higher mortality rate [p=0.008], but the significance disappeared when adjusted for age. Smoking was also associated with increased mortality. Conclusions: In urban India, mortality rates are two fold higher in people with diabetes compared to nondiabetic subjects. Cardiovascular and renal diseases are the commonest causes of death among diabetic subjects

Association of Leukocyte Count and hsCRP with Metabolic Abnormalities in Subjects with Normal Glucose Tolerance (CURES – 64)

Objective : The aim of the present study was to assess the association of leukocyte count and high sensitivity C-Reactive protein (hsCRP) with metabolic abnormalities in subjects with normal glucose tolerance. Methods : Subjects with Normal Glucose Tolerance (NGT) (n = 865) were recruited from the Chennai Urban Rural Epidemiology Study [CURES]. Standard methods were used for assessing hsCRP [Nephelometry, in a subset] and leukocytes [Flowcytometry, Sysmex SF-3000]. Insulin resistance was calculated using the Homeostasis Assessment model (HOMA-IR). Results : Body mass index, waist circumference, systolic and diastolic blood pressure, fasting plasma glucose, HbA1c, serum cholesterol, LDL cholesterol, HOMA IR and hsCRP increased significantly with increasing tertiles of leukocyte count [p for trend < 0.001]. Both leukocyte count and hsCRP showed a positive correlation with cardiovascular risk factors. Leukocyte count showed a positive correlation with hsCRP [p=0.008]. Both mean leukocyte count [p<0.001] and hsCRP [p=0.04] were higher in subjects with Metabolic Syndrome (MS), which increased with increase in number of metabolic abnormalities [p for trend <0.001]. Regression models showed leukocyte count [p<0.001] and hsCRP [p=0.03] to be associated with MS, even after adjusting for age and gender. Conclusion : A significant association exists between systemic inflammation [leukocyte count and hsCRP] and MS/ cardiovascular risk factors in Asian Indians even among non-diabetic subjects