Diabetes and Cardiovascular Risk In Mexico City (San Antonio Heart Study)

2014-08-27 03:58:00 | BioPortfolio


To determine factors beyond obesity which contribute to diabetes and cardiovascular risk in Mexicans and Mexican Americans. To test the hypothesis that at any given level of adiposity Mexican Americans will be more insulin resistant than Anglos and that the insulin resistance in Mexican Americans is proportional to the degree of Native American ancestry.



The present study was preceded by the earlier San Antonio Heart Study 1 supported under this grant. The San Antonio Heart Study 1 was a population-based survey of diabetes and cardiovascular risk factors in Mexican American and non-Hispanic whites conducted from 1979 to 1982. Participants included all men and non-pregnant women ages 24 to 64, who resided in households randomly sampled from three socio-culturally distinct neighborhoods of San Antonio. The low-income barrio residents were almost exclusively traditional Mexican-Americans. The middle-income neighborhood was ethnically balanced with equal numbers of Mexican Americans and Anglos whereas the upper income suburb was approximately 90 percent Anglo. Risk factors measured included obesity, glucose intolerance, hypertriglyceridemia, low levels of high density lipoprotein cholesterol, and blood pressure. The total number of people who were examined medically was 2,386, divided as follows: 1,288 Mexican Americans; 929 Anglos; and 169 other Hispanics such as Cubans. The San Antonio Heart Study was designed to test the hypothesis that as Mexican Americans became progressively more affluent and accultured to 'mainstream' United States culture, they would gradually lose their diabetic pattern of cardiovascular risk factors of obesity, diabetes, and hypertriglyceridemia.


Beginning in 1979, a random sample was conducted to select participants. Sampling was performed to match the two groups on obesity, thereby enabling an analysis of the ethnic differences in diabetes and cardiovascular risk factors independent of the confounding effects of obesity. For those selected, an interview and medical examination were conducted in a mobile clinic. The interview consisted of a personal and family history of diabetes and cardiovascular risk, knowledge of and attitudes towards cardiovascular risk factors, dietary questionnaire, Rose Angina questionnaire, intermittent claudication questionnaire, and medication history. The medical examination consisted of anthropometric measurements, plasma glucose, plasma insulin, hemoglobin, serum cholesterol, triglyceride, HDL, LDL, and VLDL, genetic markers, blood pressure, skin color and electrocardiogram. It was estimated that 400 diabetics wouldl be available over the four years of the study to permit a Diabetic Recall Examination. The purpose of the Diabetic Recall Examination was to assess possible end-organ complications of diabetes involving the eye, kidney, peripheral and autonomic nervous systems, and the peripheral vascular system. The assessment provided baseline data on diabetics which was used for a prospective incidence study. Beginning in 1989, a prevalence survey of type II diabetes mellitus and cardiovascular risk factors was conducted in a low-income barrio in Mexico City. Information collected on this population included demographic data, socioeconomic status, level of acculturation, medical history, diet, exercise, and smoking. The physical examination included measurements of blood pressure, obesity, body fat distribution, and skin color. The laboratory examination included measurements of lipids and lipoproteins, oral glucose tolerance tests, fasting and post-glucose load insulin concentrations and genetic markers.

Beginning in FY 1989, Michael Stern and associates carried out an epidemiologic study of type II diabetes mellitus and cardiovascular risk factors in a low-income barrio of Mexico City and compared results to those obtained in San Antonio. They recruited and interviewed subjects for data on demographics, socioeconomic status, level of acculturation, medical history, health habits including diet, physical exercise, and smoking. The physical examination included blood pressure, obesity, body fat distribution, skin color, the latter to estimate percent Native American genetic admixture. The laboratory examination included measurements of lipids and lipoproteins, an oral glucose tolerance test to determine the prevalence of diabetes according to the National Diabetes Data Group criteria, fasting and post-glucose load insulin concentrations, and genetic markers.

The study was renewed in 1996 through August, 2001. A 3.25 year followup examination (FU1) of a cohort of 2,296 Mexican men and women, ages 35-64 years at baseline, was completed. The cohort was re-examined at 3.25-year intervals (6.5 years (FU2) and 9.75 years (FU3) after baseline). The investigators tested the hypothesis that different risk factors would prevail in the early (more than 3.25 years prior to conversion to diabetes) than in the late (3.25 years or less prior to conversion) prediabetic period. They hypothesized that in the early prediabetic period risk factors associated with the Insulin Resistance Syndrome would predominate, i.e., high "specific" insulin concentration (measured by a specific immunoassay), hypertriglyceridemia, low HDL-cholesterol, and hypertension, whereas in the late prediabetic period factors associated with insulin secretory failure, i.e., increased proinsulin and low "specific" insulin, would predominate.

Michael Stern and associates assessed carotid wall thickness by ultrasonography on all subjects at FU1 and planned to repeat this at FU2. They measured advanced glycation endproduct (AGE)-modified apolipoprotein B and a panel of inflammatory risk factors (serum albumin, serum amyloid A, alpha1-acid glycoprotein, and C-reactive protein) on stored contingency specimens from baseline and FU1 in order to determine if these factors predicted accelerated thickening of carotid walls and/or the development of type II diabetes. They also quantified the extent to which carotid wall thickness and ECG documented myocardial infarction preceded clinical diabetes as predicted by the "common soil" hypothesis, i.e., the hypothesis that both type II diabetes and atherosclerosis have common genetic and environmental antecedents.

Study Design

Observational Model: Natural History


Cardiovascular Diseases




National Heart, Lung, and Blood Institute (NHLBI)

Results (where available)

View Results


Published on BioPortfolio: 2014-08-27T03:58:00-0400

Clinical Trials [1266 Associated Clinical Trials listed on BioPortfolio]

Cardiovascular Diseases in HIV-infected Subjects (HIV-HEART Study)

Human immunodeficiency virus (HIV) infection has been associated with a variety of cardiovascular diseases. Even most industrialised countries exhibit a growing and aging population of HIV...

The Effects of Aerobic Exercise in Microvascular Endothelium Function in Patients With Cardiovascular Diseases

This study evaluates the effects of different volumes of aerobic exercise training in cardiovascular parameters of patients with cardiovascular diseases enrolled in a cardiac rehabilitatio...

ARROW:identificAtion of postpRandial biomaRkers tOWards Cardiovascular Prevention

The purpose of this study is to better understand the association between the postprandial biomarker responses after a food challenge with the development of cardiovascular diseases in hea...

Development, Testing, and Validation of A Protocol To Assess Cardiovascular Reactivity in Human Populations

To develop a comprehensive protocol for assessing cardiovascular reactivity to stressors, for use in epidemiological and clinical investigations of cardiovascular diseases in healthy popul...

Cardiovascular Diseases in the Silesian Region in Poland.

The Silesian Cardiovascular Database is an observational study of all patients hospitalized due to cardiovascular diseases. The date include information on the clinical characteristics, tr...

PubMed Articles [11518 Associated PubMed Articles listed on BioPortfolio]

12-year trends in cardiovascular risk factors (2002-2005 through 2011-2014) in patients with cardiovascular diseases: Tehran lipid and glucose study.

To examine the trend of cardiovascular diseases (CVD) risk factors among a Middle Eastern population with prevalent CVD during a median follow up of 12 years.

Introduction and Update on Obesity and Cardiovascular Diseases 2018.

Pharmacological Modulation of Vagal Nerve Activity in Cardiovascular Diseases.

Cardiovascular diseases are life-threatening illnesses with high morbidity and mortality. Suppressed vagal (parasympathetic) activity and increased sympathetic activity are involved in these diseases....

Human Emotions on the Onset of Cardiovascular and Small Vessel Related Diseases.

The aim of the present study was to examine the relation between understanding of emotions and cardiovascular related diseases, namely coronary heart disease, diabetes mellitus and obesity. The unique...

Epicardial fat and osteoprotegerin - does a mutual relation exist? Pilot study.

Epicardial fat (EPI) plays important role in development of metabolic and cardiovascular diseases. According to population studies EPI represents independent risk factor of cardiovascular diseases (CV...

Medical and Biotech [MESH] Definitions

Pathological conditions involving the CARDIOVASCULAR SYSTEM including the HEART; the BLOOD VESSELS; or the PERICARDIUM.

Methods and procedures for the diagnosis of diseases or dysfunction of the cardiovascular system or its organs or demonstration of their physiological processes.

Diseases of long duration and generally slow progression. The four main types of noncommunicable diseases are CARDIOVASCULAR DISEASES (e.g., heart attacks and stroke), CANCER, chronic respiratory diseases (e.g., CHRONIC OBSTRUCTIVE PULMONARY DISEASE and ASTHMA) and DIABETES MELLITUS.

Unexpected rapid natural death due to cardiovascular collapse within one hour of initial symptoms. It is usually caused by the worsening of existing heart diseases. The sudden onset of symptoms, such as CHEST PAIN and CARDIAC ARRHYTHMIAS, particularly VENTRICULAR TACHYCARDIA, can lead to the loss of consciousness and cardiac arrest followed by biological death. (from Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005)

Dental care for patients with chronic diseases. These diseases include chronic cardiovascular, endocrinologic, hematologic, immunologic, neoplastic, and renal diseases. The concept does not include dental care for the mentally or physically disabled which is DENTAL CARE FOR DISABLED.

More From BioPortfolio on "Diabetes and Cardiovascular Risk In Mexico City (San Antonio Heart Study)"

Quick Search


Relevant Topics

Public Health
Alternative Medicine Cleft Palate Complementary & Alternative Medicine Congenital Diseases Dentistry Ear Nose & Throat Food Safety Geriatrics Healthcare Hearing Medical Devices MRSA Muscular Dyst...

Cardiovascular disease (CVD)
Acute Coronary Syndromes (ACS) Blood Cardiovascular Dialysis Hypertension Stent Stroke Vascular Cardiovascular disease (CVD) includes all the diseases of the heart and circulation including coronary heart disease (angina...

Searches Linking to this Trial