Prevalence and risk factors of hypertension in a selected South Indian population--the Chennai Urban Population Study.

OBJECTIVE: Hypertension is a major public health problem in developing countries. There is however very little population based data particularly in South India. The aim of this study is to determine the prevalence of hypertension and its associated risk factors in an urban South Indian population at Chennai. METHODS: The Chennai Urban Population Study (CUPS) is an epidemiological study involving two residential areas in Chennai in South India. Of the total of 1399 eligible subjects (age > or = 20 years), 1262 (90.2%) participated in the study. All the study subjects underwent a glucose tolerance test (GTT) and were categorized as having normal glucose tolerance (NGT), impaired glucose tolerance (IGT) or diabetes mellitus (DM). Subjects were classified as hypertensive using the criteria, systolic blood pressure (SBP) > or = 140 mm Hg, and/or diastolic blood pressure (DBP) > or = 90 mm Hg and/or treatment with anti-hypertensive drugs. Twelve-lead resting electrocardiography (ECG) was performed in 1175 individuals and peripheral Doppler studies were done in 50% of the individuals (n=631). RESULTS: The overall crude prevalence of hypertension (HTN) in this population is 21.1% (n=266) while the age standardized prevalence is 17.0%. Body mass index (BMI) and waist-hip ratio (WHR) were significantly higher (p < 0.001) in the HTN group compared to the non-hypertensive individuals. The prevalence of diabetes (p < 0.001), obesity (p < 0.001), CAD (p = 0.001) and PVD (p = 0.0055) was higher among the hypertensive compared to normotensive group. Multiple logistic regression analysis revealed HTN to be significantly associated with age (p < 0.001), body mass index (p < 0.001) and glucose intolerance (p = 0.005). CONCLUSION: The prevalence of hypertension appears to be high in this urban South Indian population and this calls for urgent steps for its prevention and control.

Comparison of colour duplex ultrasound and ankle-brachial pressure index measurements in peripheral vascular disease in type 2 diabetic patients with foot infections.

BACKGROUND AND OBJECTIVES: Peripheral vascular disease (PVD) is a common cause of morbidity and mortality and is reported to be more common among diabetic subjects compared to non-diabetic subjects. The aim of the study was to compare the specificity and sensitivity of ankle-brachial index (ABI) measured by peripheral doppler with the colour duplex ultrasound (CDU) for diagnosis of PVD. METHODS: One hundred type 2 diabetic patients admitted to our diabetic centre with foot lesions underwent both colour duplex ultrasound and ankle-brachial index measurements. PVD was diagnosed if the individual had haemodynamically significant obstruction on CDU, or if the ABI was < 0.9. The sensitivity and specificity of ABI was determined using the CDU as 'gold standard'. RESULTS: The mean age of the study group was 59.5 +/- 10.1 years and the mean duration of diabetes was 11.7 +/- 8.1 years. Of the total 100 subjects, six subjects had calcification of peripheral vessels and they were not included while calculating for sensitivity and specificity of ABI. Twenty (21.3%) subjects diagnosed as PVD by the CDU were not classified as PVD by the ABI measurements. Conversely, only three subjects (3.2%) classified as PVD by ABI had normal arteries based on CDU scanning. Overall, ABI had low sensitivity (70.6%) but a high specificity (88.5%). The overall agreement between CDU and ABI was poor (k = 0.20). CONCLUSION: ABI is a good initial screening tool but some patients with significant stenosis in lower extremities would be missed, if ABI measurement alone is used for diagnosis of PVD.

Prevalence of non-diabetic renal disease in type 2 diabetic patients in a diabetes centre in Southern India.

OBJECTIVE: The Aim of Study is to determine the prevalence of non-diabetic renal disease among South Indian type 2 diabetic subjects based on renal biopsy. METHODS: Three thousand five hundred and ninety subjects with complete records were included for the study. One hundred and forty subjects who had proteinuria but no evidence of retinopathy undertook a 24 hour proteinuric estimation. Of these 140 subjects, 28 subjects had proteinuria > 1,000 mg/day and were subjected to renal imaging. Seven subjects were excluded due to renal calculi, cysts or contracted kidneys. Of the remaining 21 diabetic subjects, one subject was excluded as he had a mild diabetic retinopathy on fundus fluorescein angiography. Of the 20 subjects included 18 participated in the renal biopsy study (response rate--90%). Renal pathology of these subjects were studied. RESULTS: Of the 18 renal biopsies, two were excluded due to different reasons. Out of 16 patients, eight (50%) had pathological changes suggestive of diabetic etiology, five (33.3%) had classical membranous nephropathy, one (6.2%) had tubulo-interstitial disease and two (12.5%) were categorized as others with minimal changes. The subjects with non-diabetic renal disease had significantly higher creatinine clearance (p = 0.024), serum cholesterol (p = 0.036), triglyceride levels (p = 0.045) and LDL cholesterol (p = 0.048) compared to subjects with diabetic nephropathy. CONCLUSION: This study suggests that even in subjects clinically suspected to have non-diabetic renal disease many may turn out to have diabetic nephropathy on renal biopsy.

Prevalence of insulin resistance syndrome in a selected south Indian population--the Chennai urban population study-7 [CUPS-7].

BACKGROUND & OBJECTIVES: Although earlier studies had shown socio-economic factors to be strongly associated with the insulin resistance syndrome (IRS) and its components, there is still a paucity of data on Indians who have increased insulin resistance. In this study, we assessed the prevalence of IRS in two socio-economic groups in an urban south Indian population. METHODS: The Chennai Urban Population Study (CUPS) is an epidemiological study involving two residential areas in Chennal in south India. Of the 1262 eligible subjects (age > or = 20 yr) who participated in the study, 1070 (76.5%) subjects who had a complete set of data were recruited for this study. Insulin resistance was calculated using the homeostasis assessment (HOMA) model. Insulin resistance syndrome was defined as the presence of insulin resistance in combination with at least 2 of the following conditions: hyperglycaemia, hypertension, dyslipidemia or central body obesity. RESULTS: The overall prevalence of IRS was 11.2 per cent (95% confidence interval: 9.4-13.3). The prevalence of the IRS in the middle-income group (18.7%) was significantly higher compared to the low income group (6.5%; P < 0.001). Multiple logistic regression analysis revealed age (P < 0.001), body mass index (P < 0.05) and socio-economic status (P = 0.014) to be associated with IRS. INTERPRETATION & CONCLUSION: The overall prevalence rate of IRS was 11.2 per cent. Age and higher socio-economic status were the risk factors for insulin resistance in this selected urban south Indian study population.

Assessment of Nipah virus transmission among pork sellers in Seremban, Malaysia.

Between September 1998 and May 1999, 265 cases of encephalitis were reported from among those involved in pig rearing. A few cases were also reported among abattoir workers. This raised questions of the risk of transmission among those who handled raw pork. A serosurvey was conducted among pork sellers in Seremban town, which is about 20 km from one of the pig rearing areas which had reported cases of encephalitis. It was found that out of the 28 pork sellers tested, only one tested positive for Nipah virus antibodies and that this pork seller also worked in an abattoir in the same district, removing the urinary bladders from slaughtered pigs. Based on these findings, it was concluded that the risk of transmission of the virus from handling raw pork appeared to be low.