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Featured researches published by Ambuj Roy.


Heart | 2011

Prevalence and outcome of subclinical rheumatic heart disease in India: The RHEUMATIC (Rheumatic Heart Echo Utilisation and Monitoring Actuarial Trends in Indian Children) study

Anita Saxena; Sivasubramanian Ramakrishnan; Ambuj Roy; Sandeep Seth; Anand Krishnan; Puneet Misra; Mani Kalaivani; Balram Bhargava; Marcus Flather; Philip A. Poole-Wilson

Objective To study the prevalence and medium term outcome of subclinical rheumatic heart disease (RHD) in India. Design Cross sectional echocardiographic screening study. Setting School children aged 5–15 years living in rural areas of north India. Patients A cross sectional echocardiographic screening study was carried out among 6270 randomly selected school children aged 5–15 years (10.8±2.6 years; 52.7% male). Of all the abnormal cases, 100 children (78%) were restudied at a mean follow-up of 15.4±6.6 months. Intervention Echocardiographic screening. Main outcome measure Echocardiography–Doppler criteria based prevalence of RHD. Results Clinical examination detected mitral regurgitation in five patients and the estimated prevalence of clinical RHD was 0.8/1000 school children. Echocardiography–Doppler diagnosed RHD in 128 cases, giving a prevalence of 20.4/1000 school children (95% CI 16.9 to 23.9/1000 children). On multivariate analysis, older age (OR 1.93, 95% CI 1.29 to 2.88; p=0.001), female sex (OR 1.84, 95% CI 1.25 to 2.72; p=0.002) and government funded school student, which is a surrogate measure of lower socioeconomic status (OR 1.55, 95% CI 1.02 to 2.34; p=0.039) were found to be independent predictors of RHD. On follow up, the severity of subclinical RHD was non-progressive in 68 children (68%) while it worsened in four (4%) and regressed in 28 children (28%). Conclusions The prevalence of RHD is several fold higher using echocardiographic screening compared with clinical examination. The prevalence is higher among girls and children of lower socioeconomic status. In the majority of cases, subclinical RHD appears to be non-progressive on medium term follow up. Routine echocardiographic screening may be indicated in populations at high risk of RHD.


Circulation | 2016

Cardiovascular Diseases in India Current Epidemiology and Future Directions

Dorairaj Prabhakaran; Panniyammakal Jeemon; Ambuj Roy

Cardiovascular diseases (CVDs) have now become the leading cause of mortality in India. A quarter of all mortality is attributable to CVD. Ischemic heart disease and stroke are the predominant causes and are responsible for >80% of CVD deaths. The Global Burden of Disease study estimate of age-standardized CVD death rate of 272 per 100 000 population in India is higher than the global average of 235 per 100 000 population. Some aspects of the CVD epidemic in India are particular causes of concern, including its accelerated buildup, the early age of disease onset in the population, and the high case fatality rate. In India, the epidemiological transition from predominantly infectious disease conditions to noncommunicable diseases has occurred over a rather brief period of time. Premature mortality in terms of years of life lost because of CVD in India increased by 59%, from 23.2 million (1990) to 37 million (2010). Despite wide heterogeneity in the prevalence of cardiovascular risk factors across different regions, CVD has emerged as the leading cause of death in all parts of India, including poorer states and rural areas. The progression of the epidemic is characterized by the reversal of socioeconomic gradients; tobacco use and low fruit and vegetable intake have become more prevalent among those from lower socioeconomic backgrounds. In addition, individuals from lower socioeconomic backgrounds frequently do not receive optimal therapy, leading to poorer outcomes. Countering the epidemic requires the development of strategies such as the formulation and effective implementation of evidence-based policy, reinforcement of health systems, and emphasis on prevention, early detection, and treatment with the use of both conventional and innovative techniques. Several ongoing community-based studies are testing these strategies.


Atherosclerosis | 2010

Impact of alcohol on coronary heart disease in Indian men.

Ambuj Roy; Dorairaj Prabhakaran; Panniyammakal Jeemon; K. R. Thankappan; Viswanathan Mohan; Lakshmy Ramakrishnan; Prashant P. Joshi; F. U. Ahmed; B. V. M. Mohan; Ram Kirti Saran; Nakul Sinha; Kolli Srinath Reddy

BACKGROUND Moderate alcohol consumption is known to be protective against coronary heart disease (CHD). However, the INTERHEART study, a case-control study of acute myocardial infarction (MI) patients, revealed that alcohol consumption in South Asians was not protective against CHD. We therefore planned to study cardiovascular risk factor and CHD prevalence among male alcohol users as compared to age matched lifetime abstainers. METHODS The subjects for this study were recruited from a cross-sectional survey carried out among employees and their family members aged 20-69 years in 10 medium-to-large industries from diverse sites in India, using a stratified random sampling technique. Information on education, behavioral, clinical and biochemical risk factors of CHD and alcohol use was obtained through standardized instruments. CHD diagnosis was based on Rose Questionnaire or a prior physician diagnosed CHD. RESULTS A total of 4465 subjects were present or past alcohol users. The mean age of alcohol users and lifetime abstainers was 42.8+/-11.0 years and 42.8+/-11.1 years, respectively (p=0.90). Systolic blood pressure and diastolic blood pressure were significantly higher in alcohol users (128.7+/-17.6 mmHg/80.1+/-11.3 mmHg) as compared to lifetime abstainers (126.9+/-15.9 mmHg/79.5+/-10.3 mmHg, p<0.01). Fasting blood sugar in alcohol users (98.7+/-30.5 mg%) was also significantly higher than lifetime abstainers (96.6+/-26.0 mg%, p<0.01). Total cholesterol was lower in alcohol users (179.1+/-41.1 mg%) as compared to lifetime abstainers (182.7+/-38.2 mg%, p<0.01). HDL cholesterol was higher in alcohol users (42.9+/-10.8 mg%) as compared to lifetime abstainers (41.3+/-10.0 mg%, p<0.01). Body mass index (BMI) was lower in alcohol users as compared to lifetime abstainers (22.7+/-4.1 kg/m2 vs. 24.0+/-3.3 kg/m2, p<0.001). Tobacco use was significantly higher in alcohol users (63.1% vs. 20.7%). The odds ratio (OR) of having CHD after adjusting for tobacco use, BMI and education was 1.4 (95%CI 1.0-1.9) in alcohol users as compared to controls. The OR was 1.2 (95%CI 0.8-1.6) in occasional alcohol users, 1.6 (95%CI 1.0-2.2) in regular alcohol users and 2.1 (95% CI 1.1-3.0) in past alcohol users as compared to controls. CONCLUSION We did not observe an inverse (protective) association between alcohol intake and the prevalence of CHD. In contrast, our study indicated an association in the reverse direction, suggesting possible harm of alcohol for coronary risk in Indian men. This relationship needs to be further examined in large, prospective study.


International Journal of Cardiology | 2016

Heart Failure in Africa, Asia, the Middle East and South America: The INTER-CHF study

Hisham Dokainish; Koon K. Teo; Jun Zhu; Ambuj Roy; Khalid F. AlHabib; Ahmed ElSayed; Lia Palileo-Villaneuva; Patricio López-Jaramillo; K.M. Karaye; Khalid Yusoff; Andres Orlandini; Karen Sliwa; Charles Mondo; Fernando Lanas; Dorairaj Prabhakaran; Amr Badr; Mohamed ElMaghawry; Albertino Damasceno; Kemi Tibazarwa; Emilie P. Belley-Côté; Kumar Balasubramanian; Magdi H. Yacoub; Mark D. Huffman; Karen Harkness; Alex Grinvalds; Robert S. McKelvie; Salim Yusuf

BACKGROUND There are few data on heart failure (HF) patients from Africa, Asia, the Middle East and South America. METHODS INTER-CHF is a prospective study that enrolled HF patients in 108 centers in 16 countries from 2012 to 2014. Consecutive ambulatory or hospitalized adult patients with HF were enrolled. Baseline data were recorded on sociodemographics, clinical characteristics, HF etiology and treatments. Age- and sex-adjusted results are reported. RESULTS We recruited 5813 HF patients: mean(SE) age=59(0.2)years, 39% female, 65% outpatients, 31% from rural areas, 26% with HF with preserved ejection fraction, with 1294 from Africa, 2661 from Asia, 1000 from the Middle-East, and 858 from South America. Participants from Africa-closely followed by Asians-were younger, had lower literacy levels, and were less likely to have health or medication insurance or be on beta-blockers compared with participants from other regions, but were most likely to be in NYHA class IV. Participants from South America were older, had higher insurance and literacy levels, and, along with Middle Eastern participants, were more likely to be on beta-blockers, but had the lowest proportion in NYHA IV. Ischemic heart disease was the most common HF etiology in all regions except Africa where hypertensive heart disease was most common. CONCLUSIONS INTER-CHF describes significant regional variability in socioeconomic and clinical factors, etiologies and treatments in HF patients from Africa, Asia, the Middle East and South America. Opportunities exist for improvement in health/medication insurance rates and proportions of patients on beta blockers, particularly in Africa and Asia.


Global heart | 2012

Pathophysiological Mechanisms of Tobacco-Related CVD

Salman Salahuddin; Dorairaj Prabhakaran; Ambuj Roy

Cigarette smoking is a leading preventable risk factor for the development and progression of cardiovascular diseases (CVDs). Epidemiologic studies conclusively prove that both active smoking and secondhand smoke contribute significantly to morbidity and mortality related to CVD. Cigarette smoke is a mixture of several toxic chemicals, of which nicotine, carbon monoxide, and oxidant chemicals are most commonly implicated in the pathogenesis of cardiovascular disease. Tobacco causes endothelial dysfunction, inflammation, insulin resistance, alteration of lipid profile, hemodynamic alterations, and a hypercoagulable state. All of these act synergistically as pathobiologic mechanisms of atherothrombosis in tobacco users.


Indian Journal of Medical Research | 2010

Role of biomarkers in risk stratification of acute coronary syndrome.

Cm Nagesh; Ambuj Roy

Diagnosis of acute coronary syndrome (ACS) encompasses a wide spectrum of myocardial ischaemia varying from assuredly benign to potentially fatal. Cardiac biomarkers have had a major impact on the management of this disease and are now the cornerstone in its diagnosis and prognosis. In this review we discuss both the established and the newer emerging biomarkers in ACS and their role in highlighting not only myocardial necrosis but also different facets of the pathophysiology of ACS. The future of cardiac biomarker testing may be in multimarker testing to better characterize each patient of ACS and thus tailor both short-term and long-term therapy accordingly. This novel concept, however, needs to be tested in clinical trials for its incremental value and cost-effectiveness.


Indian heart journal | 2015

Independent association of severe vitamin D deficiency as a risk of acute myocardial infarction in Indians.

Ambuj Roy; Ramakrishnan Lakshmy; Mohamad Tarik; Nikhil Tandon; K. Srinath Reddy; Dorairaj Prabhakaran

BACKGROUND Association of vitamin D deficiency with coronary heart disease (CHD) has been widely reported. Emerging data has shown high prevalence of vitamin D deficiency among Indians. However, this association has not been studied in Indians. METHODS A case-control study with 120 consecutive cases of first incident acute myocardial infarction (MI) and 120 age and gender matched healthy controls was conducted at All India Institute of Medical Sciences, New Delhi. The standard clinical and biochemical risk factors for MI were assessed for both cases and controls. Serum 25 (OH) vitamin D assay was performed from stored samples for cases and controls using radioimmunoassay. RESULTS Vitamin D deficiency [25(OH) D < 30 ng/ml] was highly prevalent in cases and controls (98.3% and 95.8% respectively) with median levels lower in cases (6 ng/ml and 11.1 ng/ml respectively; p < 0.001). The cases were more likely to have diabetes, hypertension and consume tobacco and alcohol. They had higher waist hip ratio, total and LDL cholesterol. Multivariate logistic regression analysis revealed severe vitamin D deficiency [25(OH) vitamin D < 10 ng/ml] was associated with a risk of MI with an odds ratio of 4.5 (95% CI 2.2-9.2). CONCLUSIONS This study reveals high prevalence of vitamin D deficiency among cases of acute MI and controls from India, with levels of 25 (OH)D being significantly lower among cases. Despite rampant hypovitaminosis, severe vitamin D deficiency was associated with acute MI after adjusting for conventional risk factors. This association needs to be tested in larger studies in different regions of the country.


Journal of the American Heart Association | 2016

Development of a Smartphone-Enabled Hypertension and Diabetes Mellitus Management Package to Facilitate Evidence-Based Care Delivery in Primary Healthcare Facilities in India: The mPower Heart Project.

Vamadevan S. Ajay; Devraj Jindal; Ambuj Roy; Vidya Venugopal; Rakshit Sharma; Abha Pawar; Sanjay Kinra; Nikhil Tandon; Dorairaj Prabhakaran

Background The high burden of undetected and undertreated hypertension and diabetes mellitus is a major health challenge worldwide. The mPower Heart Project aimed to develop and test a feasible and scalable intervention for hypertension and diabetes mellitus by task‐sharing with the use of a mobile phone–based clinical decision support system at Community Health Centers in Himachal Pradesh, India. Methods and Results The development of the intervention and mobile phone–based clinical decision support system was carried out using mixed methods in five Community Health Centers. The intervention was subsequently evaluated using pre–post evaluation design. During intervention, a nurse care coordinator screened, examined, and entered patient parameters into mobile phone–based clinical decision support system to generate a prescription, which was vetted by a physician. The change in systolic blood pressure, diastolic blood pressure, and fasting plasma glucose (FPG) over 18 months of intervention was quantified using generalized estimating equations models. During intervention, 6797 participants were enrolled. Six thousand sixteen participants had hypertension (mean systolic blood pressure: 146.1 mm Hg, 95% CI: 145.7, 146.5; diastolic blood pressure: 89.52 mm Hg, 95% CI: 89.33, 89.72), of which 3152 (52%) subjects were newly detected. Similarly, 1516 participants had diabetes mellitus (mean FPG: 177.9 mg/dL, 95% CI: 175.8, 180.0), of which 450 (30%) subjects were newly detected. The changes in systolic blood pressure, diastolic blood pressure, and FPG observed at 18 months of follow‐up were −14.6 mm Hg (95% CI: −15.3, −13.8), −7.6 mm Hg (CI: −8.0, −7.2), and −50.0 mg/dL (95% CI: −54.6, −45.5), respectively, and were statistically significant even after adjusting for age, sex, and Community Health Center. Conclusions A nurse‐facilitated, mobile phone–based clinical decision support system‐enabled intervention in primary care was associated with improvements in blood pressure and blood glucose control and has the potential to scale‐up in resource poor settings. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifiers: NCT01794052. Clinical Trial Registry—India: CTRI/2013/02/003412.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2014

Incremental Value of Left Ventricular Systolic and Diastolic Function to Determine Outcome in Patients with Acute ST‐Segment Elevation Myocardial Infarction: The Echocardiographic Substudy of the OASIS‐6 Trial

Hisham Dokainish; Mahadevan Rajaram; Dorairaj Prabhakaran; Rizwan Afzal; Andres Orlandini; Lidia Staszewsky; Maria Grazia Franzosi; Javier Llanos; Elena Martinoli; Ambuj Roy; Salim Yusuf; Shamir R. Mehta; Eva Lonn

The echocardiographic substudy of the OASIS‐6 trial evaluated the prognostic implications of left ventricle (LV) systolic and diastolic dysfunction early postacute ST‐segment elevation myocardial infarction (STEMI) in patients treated with fondaparinux versus usual care.


Indian Journal of Pediatrics | 2013

Cardiovascular Disease Risk Factors: A Childhood Perspective

Pradeep A. Praveen; Ambuj Roy; Dorairaj Prabhakaran

Atherosclerotic cardiovascular disease (CVD) is one of the leading causes of death and disability worldwide including in developing countries like India. Indians are known to be predisposed to CVD, which occur almost a decade earlier in them. Though these diseases manifest in the middle age and beyond, it is now clear that the roots of CVD lie in childhood and adolescence. Many of the conventional risk factors of CVD such as high blood pressure, dyslipidemia, tobacco use, unhealthy diet and obesity have their beginnings in childhood and then track overtime. It is thus important to screen and identify these risk factors early and treat them to prevent onset of CVD. Similarly community based strategies to prevent onset of these risk factors is imperative to tackle this burgeoning public health crisis especially in countries like ours with limited resources.

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Dorairaj Prabhakaran

Public Health Foundation of India

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Nikhil Tandon

All India Institute of Medical Sciences

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Nitish Naik

All India Institute of Medical Sciences

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Gautam Sharma

All India Institute of Medical Sciences

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Lakshmy Ramakrishnan

All India Institute of Medical Sciences

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Anand Krishnan

All India Institute of Medical Sciences

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Vinay K. Bahl

All India Institute of Medical Sciences

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Pradeep A. Praveen

All India Institute of Medical Sciences

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Anita Saxena

All India Institute of Medical Sciences

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Balram Bhargava

All India Institute of Medical Sciences

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