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Abstract: Objective: To demonstrate how mixed models may be used to estimate treatment effects, and inform decisions on the need for monitoring initial response. Study Design and Setting: Mixed models were used to analyze data from the Perindopril Protection Against Recurrent Stroke Study (PROGRESS), which examined the effects of perindopril and indapamide in 6,105 patients at high risk of a cerebrovascular event. Results: The mean effect of perindopril was to lower blood pressure (BP) (systolic/diastolic) by 6/3mmHg. The mean effects of perindopril/indapamide varied according to baseline BP, and lowering of BP ranged from 9/5 to 14/5mmHg (for individuals with a baseline systolic BP <140 and >150mmHg, respectively). We found no variation in the effects of treatment on BP for either perindopril alone or in combination with indapamide. The effects of treatment on the individual can be predicted from the mean effect of treatment for the group (perindopril) or baseline systolic BP subgroup (perindopril/indapamide). Conclusion: Monitoring initial treatment response is unnecessary for antihypertensives similar to those examined in this study. To address this issue for other therapies, we suggest that trials should report estimates of treatment effects from mixed models, and the CONSORT statement should be expanded to include this item. [Copyright &y& Elsevier]

Abstract: Asian Indians appear particularly susceptible to coronary heart disease compared with other ethnic groups. We compared the effects of vascular risk factors on carotid intima–media thickness (IMT) in a population of South Asians from Andhra Pradesh, India with a population of Caucasians from Perth, Australia. Cardiovascular risk factors and ultrasound-assessed carotid IMT were measured in randomly selected adults from two villages in rural India (n =303) and compared to those for randomly sampled adults from Australia (n =1111). Regression models with interaction terms were used to compare the strengths of associations between risk factors and carotid IMT, in these two populations. There were stronger associations of cholesterol (p for interaction=0.009) and diabetes (p =0.04) with carotid IMT in the Indian compared to the Australian population. Also, while increasing HDL-cholesterol was associated with decreasing carotid IMT in the Australian population the reverse was true for the Indian population (p <0.001). The associations with IMT of blood pressure, triglycerides, age, HDL to total cholesterol ratio, glucose, BMI, waist, waist to hip ratio and smoking were not different between the populations. Greater adverse effects of total cholesterol and diabetes on atherosclerosis and no protective effect of HDL-cholesterol amongst Asian Indians provide a novel possible explanation for observed excess rates of cardiovascular disease amongst these populations. [Copyright &y& Elsevier]

Abstract: Background and objective: Both migrant and local urban populations of Asian Indians have high rates of cardiovascular disease. Metabolic risk factors appear key to this phenomenon but data from rural India are few. We sought to determine the prevalence and distribution of lipids, obesity and metabolic syndrome in a rural region of Andhra Pradesh. Methods: Sampling was done in 20 villages representative of the project area with an age- and sex-stratified group of 4535 adults ≥30 years selected at random from a local census list. The sample represented 13% of all adults ≥30 years in the 20 villages with a response rate of 81%. All participants had interviewer administered questionnaire, physical examination and fasting finger-prick glucose. Every fourth individual had venous blood testing for lipid profile (n =1085). Analysis was done using weighting to obtain estimates of risk factor levels for the adult population in the 20 villages. In addition to standard WHO and 2005 NCEP-ATPIII classifications, exploratory ‘Asian’ definitions were used for overweight and abdominal obesity. Results: The population mean levels of total, LDL, HDL-cholesterol and triglycerides were 4.5 (4.4–4.6) mmol/L, 2.8 (2.7–2.9) mmol/L, 1.1 (1.06–1.13) mmol/L, 1.5 (1.4–1.6) mmol/L for men; and 4.8 (4.7–4.9) mmol/L, 3.0 (3.0–3.1) mmol/L, 1.2 (1.16–1.22) mmol/L, 1.3 (1.2–1.4) mmol/L for women. 18.4% of men and 26.3% of women were overweight rising to 32.4% of men and 41.4% of women if ‘Asian’ definitions were used. Criteria for NCEP-ATPIII metabolic syndrome were met by 26.9% of men and 18.4% of women with figures of 32.5% and 23.9%, respectively, if ‘Asian’ waist cut-offs were substituted. Conclusions: Dyslipidaemia, adiposity and metabolic syndrome were common in this rural Indian population and prevalence was much greater if proposed Asian definitions for adiposity were used. Metabolic risk factors likely play a major role in cardiovascular disease in this region. [Copyright &y& Elsevier]