Dr. Wanpen Vongpatanasin[/caption]
Wanpen Vongpatanasin, M.D.
Professor of Medicine
Norman & Audrey Kaplan Chair in Hypertension
Fredric L. Coe Professorship in Nephrolithiasis and Mineral Metabolism Research
Director, Hypertension Section,
Cardiology Division,
UT Southwestern Medical Center
Dallas, TX 75390-8586
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Aortic stiffness is known to be associated with cardiovascular disease, including heart attack, stroke, and heart failure, possibly related to increase afterload to the left ventricle. Previous studies have not directly assessed proximal aortic function among ethnic minorities in the United States. We evaluated the multiethnic, population-based Dallas Heart Study participants (N=2544, 54.2% women, 49.7% Black) who underwent cardiovascular magnetic resonance imaging (CMR) at 1.5 Tesla. Aortic stiffness and characteristic impedance (Zc) were determined from aortic arch PWV and lumen area measurements. Linear regression was used to evaluate ethnic differences in proximal aortic wall stiffness using aortic arch PWV and Zc as dependent variables with and without adjustment for traditional cardiovascular risk factors.
MedicalResearch.com Interview with:
Dr. Therese Tillin
Research Fellow, Cardiometabolic Phenotyping Group
Institute of Cardiovascular Science
Faculty of Pop Health Sciences
Medical Research: What is the background for this study? What are the main findings?
Dr. Tillin: The global burden of type 2 diabetes is rising rapidly and people of South Asian origins (from the Indian subcontinent) remain at much higher risk of developing diabetes than people of European origin. Why is this? Although it is thought that increased levels of obesity around the waist level, diet, physical activity levels and genetic factors contribute, no study to date has been able to tease out fully the underlying causes for the added risk in South Asian people. However, it is likely that complex metabolic disturbances may play an important role.
We have been studying a British cohort of people of European and South Asian origin for nearly 20 years and have used nuclear magnetic resonance spectroscopy to build a profile of amino acids in blood samples that were collected at the start of the study between 1988 and 1991. We found that higher levels of some amino acids, in particular tyrosine, were already present in non-diabetic South Asian individuals back then. Some of these amino acids, again especially tyrosine, more strongly predicted later development of type 2 diabetes in the South Asian people than in the Europeans in our study, even after adjustment for other risk factors such as obesity and insulin resistance. A given increase (one standard deviation) in tyrosine increased risk of developing diabetes by just 10% in Europeans, while in South Asians the increase in risk was 47%.
MedicalResearch.com Interview with:
Rachel Patzer, PhD, MPH
Assistant Professor
Emory University School of Medicine
Department of Surgery, Division of Transplantation
MedicalResearch.com: What are the main findings of the study?
Dr. Patzer: We found significant racial/ethnic differences in important health outcomes among pediatric and adolescent patients who received a liver transplantation at a large transplant center in the Southeastern U.S., where rates of mortality and graft failure were higher among minorities compared to white patients.